Trial Outcomes & Findings for Safety and Tolerability of M254 in Healthy Volunteers and Immune Thrombocytopenic Purpura (ITP) Patients (NCT NCT03866577)

Last Updated: 2025-05-28

Results Overview

An AE is any untoward medical event that occurs in a participant administered an investigational product, and it does not necessarily indicate only events with clear causal relationship with the relevant investigational product. A TEAE was defined as any event not present prior to administration of the study drug or any event already present that worsened in either severity or frequency following exposure to the study drug. Severity was graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 5.0. Severity scale ranges from Grade 1 (Mild) to Grade 5 (Death). Grade 1= Mild, Grade 2= Moderate, Grade 3= Severe, Grade 4= Life-threatening, and Grade 5= Death related to adverse event. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.

Recruitment status

TERMINATED

Study phase

PHASE1/PHASE2

Target enrollment

50 participants

Primary outcome timeframe

From Day 1 up to Day 29

Results posted on

2025-05-28

Participant Flow

Part C Group 2 and Part D of the study was not conducted as planned due to early study termination.

Participant milestones

Participant milestones
Measure	Part A: Pooled Placebo All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg and IV Immunoglobulin (IVIg) 1000 mg/kg Participants with immune thrombocytopenia purpura (ITP) received a single IV infusion of M254 20 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg and IVIg 1000 mg/kg Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg and IVIg 1000 mg/kg Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg and IVIg 1000 mg/kg Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1 followed by a single IV infusion of M254 120 mg/kg on Day 29.
Overall Study STARTED	7	3	3	3	3	3	3	2	5	5	2	6	5
Overall Study COMPLETED	7	3	3	3	3	3	3	2	4	3	2	5	5
Overall Study NOT COMPLETED	0	0	0	0	0	0	0	0	1	2	0	1	0

Reasons for withdrawal

Reasons for withdrawal
Measure	Part B: M254 60 mg/kg and IVIg 1000 mg/kg Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg and IVIg 1000 mg/kg Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.
Overall Study Protocol Violation	0	0	1
Overall Study Withdrawal by Subject	1	1	0
Overall Study Not qualified for IVIg infusion	0	1	0

Baseline Characteristics

Safety and Tolerability of M254 in Healthy Volunteers and Immune Thrombocytopenic Purpura (ITP) Patients

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Part A: Pooled Placebo n=7 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg and IV Immunoglobulin (IVIg) 1000 mg/kg n=2 Participants Participants with immune thrombocytopenia purpura (ITP) received a single IV infusion of M254 20 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg and IVIg 1000 mg/kg n=5 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg and IVIg 1000 mg/kg n=5 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg and IVIg 1000 mg/kg n=2 Participants Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg n=6 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1 followed by a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg n=5 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1 followed by a single IV infusion of M254 120 mg/kg on Day 29.	Total n=50 Participants Total of all reporting groups
Age, Continuous	32.9 years STANDARD_DEVIATION 10.9 • n=5 Participants	31.3 years STANDARD_DEVIATION 7.64 • n=7 Participants	32 years STANDARD_DEVIATION 13.75 • n=5 Participants	27 years STANDARD_DEVIATION 1 • n=4 Participants	29 years STANDARD_DEVIATION 7.81 • n=21 Participants	32.7 years STANDARD_DEVIATION 15.53 • n=8 Participants	24.3 years STANDARD_DEVIATION 4.51 • n=8 Participants	44 years STANDARD_DEVIATION 4.24 • n=24 Participants	51.8 years STANDARD_DEVIATION 11.45 • n=42 Participants	44 years STANDARD_DEVIATION 12.94 • n=42 Participants	54.5 years STANDARD_DEVIATION 13.44 • n=42 Participants	58 years STANDARD_DEVIATION 14.48 • n=42 Participants	60 years STANDARD_DEVIATION 12.63 • n=36 Participants	41.7 years STANDARD_DEVIATION 15.98 • n=36 Participants
Sex: Female, Male Female	4 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants	2 Participants n=4 Participants	0 Participants n=21 Participants	2 Participants n=8 Participants	2 Participants n=8 Participants	1 Participants n=24 Participants	3 Participants n=42 Participants	4 Participants n=42 Participants	1 Participants n=42 Participants	2 Participants n=42 Participants	2 Participants n=36 Participants	26 Participants n=36 Participants
Sex: Female, Male Male	3 Participants n=5 Participants	2 Participants n=7 Participants	1 Participants n=5 Participants	1 Participants n=4 Participants	3 Participants n=21 Participants	1 Participants n=8 Participants	1 Participants n=8 Participants	1 Participants n=24 Participants	2 Participants n=42 Participants	1 Participants n=42 Participants	1 Participants n=42 Participants	4 Participants n=42 Participants	3 Participants n=36 Participants	24 Participants n=36 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	1 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=36 Participants	1 Participants n=36 Participants
Race (NIH/OMB) Asian	1 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	1 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=36 Participants	2 Participants n=36 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=36 Participants	0 Participants n=36 Participants
Race (NIH/OMB) Black or African American	0 Participants n=5 Participants	1 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=36 Participants	1 Participants n=36 Participants
Race (NIH/OMB) White	6 Participants n=5 Participants	1 Participants n=7 Participants	3 Participants n=5 Participants	1 Participants n=4 Participants	3 Participants n=21 Participants	3 Participants n=8 Participants	3 Participants n=8 Participants	2 Participants n=24 Participants	5 Participants n=42 Participants	5 Participants n=42 Participants	2 Participants n=42 Participants	6 Participants n=42 Participants	5 Participants n=36 Participants	45 Participants n=36 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	1 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=36 Participants	1 Participants n=36 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=36 Participants	0 Participants n=36 Participants
Region of Enrollment Belgium	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	1 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=36 Participants	1 Participants n=36 Participants
Region of Enrollment Hungary	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	0 Participants n=42 Participants	2 Participants n=42 Participants	1 Participants n=42 Participants	1 Participants n=42 Participants	0 Participants n=36 Participants	4 Participants n=36 Participants
Region of Enrollment Italy	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	1 Participants n=36 Participants	1 Participants n=36 Participants
Region of Enrollment Netherlands	7 Participants n=5 Participants	3 Participants n=7 Participants	3 Participants n=5 Participants	3 Participants n=4 Participants	3 Participants n=21 Participants	3 Participants n=8 Participants	3 Participants n=8 Participants	0 Participants n=24 Participants	1 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	1 Participants n=42 Participants	0 Participants n=36 Participants	27 Participants n=36 Participants
Region of Enrollment Poland	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	2 Participants n=24 Participants	3 Participants n=42 Participants	3 Participants n=42 Participants	1 Participants n=42 Participants	4 Participants n=42 Participants	2 Participants n=36 Participants	15 Participants n=36 Participants
Region of Enrollment Spain	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	0 Participants n=42 Participants	2 Participants n=36 Participants	2 Participants n=36 Participants

PRIMARY outcome

Timeframe: From Day 1 up to Day 29

Population: Safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=7 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=2 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=2 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=5 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=4 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period n=5 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period n=3 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period n=2 Participants Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period n=2 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period n=6 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period n=5 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Number of Participants With Treatment-emergent Adverse Events (TEAEs) by Severity	6 Participants	3 Participants	3 Participants	3 Participants	0 Participants	3 Participants	3 Participants	1 Participants	0 Participants	2 Participants	2 Participants	1 Participants	1 Participants	0 Participants	0 Participants	1 Participants	0 Participants	2 Participants	2 Participants

PRIMARY outcome

Timeframe: From Day 1 up to Day 29

Population: Safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo.

Number of participants with clinically significant laboratory abnormalities (chemistry, hematology, urinalysis and coagulation) were reported. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=7 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=2 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=5 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=2 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period n=6 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Number of Participants With Clinically Significant Abnormalities in Clinical Laboratory Values	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	1 Participants	—	—	—	—	—	—

PRIMARY outcome

Timeframe: From Day 1 up to Day 29

Population: Safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo.

Number of participants with clinically significant abnormalities in vital signs (blood pressure \[systolic blood pressure {SBP} and diastolic blood pressure {DBP}\], pulse rate, respiratory rate, and body temperature) were reported. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=7 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=2 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=5 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=2 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period n=6 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Number of Participants With Clinically Significant Abnormalities in Vital Signs	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	1 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	1 Participants	—	—	—	—	—	—

PRIMARY outcome

Timeframe: From Day 1 up to Day 29

Population: Safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo.

Number of participants with clinically significant abnormalities in ECGs were reported. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=7 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=2 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=5 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=2 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period n=6 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Number of Participants With Clinically Significant Abnormalities in Electrocardiograms (ECGs)	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	—	—	—	—	—	—

PRIMARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

Population: The full analysis set consisted of all participants who received at least 1 dose of M254 or IVIg or placebo and for whom at least 1 post-infusion pharmacodynamics (PD) assessment was completed. Here, 'N' (number of participants analyzed) indicates number of participants evaluable for this outcome measure.

Rmax is defined as the maximum observed response of M254 on platelet count. Baseline was the pre-dose sample. Data was planned to be collected and analyzed Part C only. For Part C, data were collected and analyzed on the pooled population per the study drug (M254 120 mg/kg and IVIg 1000 mg/kg) which the participants received.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=11 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=10 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Part C: Maximum Observed Response of M254 (Rmax) on Platelet Count	62.4 10^9 cells per liter Standard Deviation 20.1	136 10^9 cells per liter Standard Deviation 70.0	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—

PRIMARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

Population: The full analysis set consisted of all participants who received at least 1 dose of M254 or IVIg or placebo and for whom at least 1 post-infusion PD assessment was completed. Here, 'N' (number of participants analyzed) indicates number of participants evaluable for this outcome measure.

Change from baseline in Rmax of M254 in platelet count was reported. Rmax is defined as the maximum observed response of M254. Baseline was the predose sample. Therapeutic platelet count was defined as \>=50\*10\^9 cells/L. Platelet response of \>=20\*10\^9 cells/L was considered as increase from baseline. Data was planned to be collected and analyzed for Part C only. For Part C, data were collected and analyzed on the pooled population per the study drug (M254 120 mg/kg and IVIg 1000 mg/kg) which the participants received.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=11 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=10 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Part C: Change From Baseline in Rmax of M254 in Platelet Count	28.8 10^9 cells per liter Standard Deviation 22.2	10.5 10^9 cells per liter Standard Deviation 67.3	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—

PRIMARY outcome

Timeframe: Predose (baseline) up to Day 14 post dose

AUEC(0-Day 14) is defined as the area under effect curve of the change from baseline in platelet count from Day 0 to Day 14 of M254. Baseline was the predose sample. Data was planned to be collected and analyzed for Part C only. For Part C, data were collected and analyzed on the pooled population per the study drug (M254 120 mg/kg and IVIg 1000 mg/kg) which the participants received.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=11 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=10 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Part C: Area Under Effect Curve of the Change From Baseline in Platelet Count From Day 0 to Day 14 (AUEC[0-Day 14]) of M254	3938 10^9 cells *hours per liter Standard Deviation 3952	21199 10^9 cells *hours per liter Standard Deviation 19349	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—

PRIMARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

AUEC(0-Day 28) is defined as the area under effect curve of the change from baseline in platelet count from Day 0 to Day 28 of M254. Baseline was the predose sample. Data was planned to be collected and analyzed for Part C only. For Part C, data were collected and analyzed on the pooled population per the study drug (M254 120 mg/kg and IVIg 1000 mg/kg) the participants received.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=11 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=10 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Part C: Area Under Effect Curve of the Change From Baseline in Platelet Count From Day 0 to Day 28 (AUEC[0-Day 28]) of M254	5774 10^9 cells *hours per liter Standard Deviation 9453	29985 10^9 cells *hours per liter Standard Deviation 29265	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—

SECONDARY outcome

Timeframe: Up to Day 29

Population: The full analysis set consisted of all participants who were included in the safety set for whom at least 1 post-infusion PD assessment was completed. Here, N (number of participants analyzed) indicates number of participants evaluable for this outcome measure.

Number of participants with overall platelet response after M254 administration compared to IVIg were reported. Overall platelet response rate is defined as reaching the therapeutic platelet count. A therapeutic platelet count is defined as greater than or equal to (\>=) 50\*10\^9 cells/liter (L) and an increase from baseline of \>=20\*10\^9 cells/L. Data was planned to be collected and analyzed for Part C only. For Part C, data were collected and analyzed on the pooled population per the study drug (M254 120 mg/kg and IVIg 1000 mg/kg) the participants received.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=11 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=10 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Part C: Number of Participants With Overall Platelet Response After M254 Administration Compared to IVIg	8 Participants	9 Participants	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—

SECONDARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

Population: Pharmacokinetic (PK) data analysis set included all randomized participants who received at least 1 dose of M254 or IVIg or placebo with at least 4 evaluable data points adequate to create an evaluable plasma concentration profile of M254.

Cmax is defined as the maximum observed plasma concentration of M254. Baseline was the predose sample. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. In Part C, combined data of both arms of Group 1 is presented as planned.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=7 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=2 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=5 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=2 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period n=11 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Maximum Observed Plasma Concentration (Cmax) of M254	3.20 micrograms per milliliter (mcg/mL) Interval 0.6 to 6.1	53.9 micrograms per milliliter (mcg/mL) Interval 51.5 to 55.3	174 micrograms per milliliter (mcg/mL) Interval 172.0 to 242.0	575 micrograms per milliliter (mcg/mL) Interval 532.0 to 664.0	1240 micrograms per milliliter (mcg/mL) Interval 1148.0 to 1351.0	2684 micrograms per milliliter (mcg/mL) Interval 2423.0 to 3099.0	5444 micrograms per milliliter (mcg/mL) Interval 3910.0 to 6316.0	431 micrograms per milliliter (mcg/mL) Interval 383.0 to 479.0	1338 micrograms per milliliter (mcg/mL) Interval 728.0 to 1724.0	2650 micrograms per milliliter (mcg/mL) Interval 2480.0 to 3548.0	5624 micrograms per milliliter (mcg/mL) Interval 4805.0 to 6444.0	3068 micrograms per milliliter (mcg/mL) Interval 2341.0 to 6008.0	—	—	—	—	—	—	—

SECONDARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

Tmax is defined as the time to reach the maximum observed plasma concentration of M254. Baseline was the predose sample. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. In Part C, combined data of both arms of Group 1 is presented as planned.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=7 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=2 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=5 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=2 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period n=11 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Time to Reach Maximum Observed Plasma Concentration (Tmax) of M254	338.68 hours Interval 336.98 to 507.73	0.60 hours Interval 0.6 to 1.1	0.45 hours Interval 0.43 to 2.33	0.77 hours Interval 0.77 to 1.03	1.23 hours Interval 1.2 to 3.18	1.83 hours Interval 1.7 to 2.63	2.62 hours Interval 2.4 to 2.67	1.02 hours Interval 0.87 to 1.17	1.48 hours Interval 1.12 to 1.67	1.93 hours Interval 1.67 to 2.07	2.74 hours Interval 2.53 to 2.95	1.85 hours Interval 1.6 to 2.13	—	—	—	—	—	—	—

SECONDARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

Population: PK data analysis set included all randomized participants who received at least 1 dose of M254 or IVIg or placebo with at least 4 evaluable data points adequate to create an evaluable plasma concentration profile of M254. Here, 'N' (number of participants analyzed) indicates number of participants evaluable for this outcome measure.

AUC(0-Infinity) is defined as area under the plasma concentration-time curve from time 0 to infinite time of M254. Baseline was the predose sample. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. In Part C, combined data of both arms of Group 1 is presented as planned.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=7 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=2 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=5 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=1 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period n=10 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Area Under the Plasma Concentration-time Curve From Time Zero to Infinite Time (AUC[0-Infinity]) of M254	NA microgramshour milliliter (mcgh/mL) 'NA' signifies that the median and full range (lower and upper limits) data could not be calculated due to insufficient data available for reliable parameter calculation.	21488 microgramshour milliliter (mcgh/mL) Interval 12867.0 to 24589.0	72050 microgramshour milliliter (mcgh/mL) Interval 68012.0 to 87057.0	210916 microgramshour milliliter (mcgh/mL) Interval 201291.0 to 223299.0	645641 microgramshour milliliter (mcgh/mL) Interval 521893.0 to 654506.0	1178098 microgramshour milliliter (mcgh/mL) Interval 997104.0 to 1351535.0	2196380 microgramshour milliliter (mcgh/mL) Interval 1568703.0 to 2620469.0	132265 microgramshour milliliter (mcgh/mL) Interval 109746.0 to 154785.0	423957 microgramshour milliliter (mcgh/mL) Interval 281920.0 to 527941.0	928888 microgramshour milliliter (mcgh/mL) Interval 847526.0 to 1000004.0	1839253 microgramshour milliliter (mcgh/mL) Interval 1839253.0 to 1839253.0	1112165 microgramshour milliliter (mcgh/mL) Interval 693431.0 to 1377293.0	—	—	—	—	—	—	—

SECONDARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

AUC(0-last) is defined as area under the plasma concentration-time curve from time 0 to time of the last quantifiable concentration of M254. AUC(0-last) is calculated by linear-linear trapezoidal summation. Baseline was the predose sample. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. In Part C, combined data of both arms of Group 1 is presented as planned.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=7 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=2 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=5 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=2 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period n=11 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Area Under the Plasma Concentration-time Curve From Time Zero to Time of Last Quantifiable Concentration (AUC[0-Last]) of M254	593 mcg*h/mL Interval 52.5 to 1441.0	11531 mcg*h/mL Interval 9770.0 to 12701.0	39509 mcg*h/mL Interval 36176.0 to 47809.0	111564 mcg*h/mL Interval 105884.0 to 121740.0	272532 mcg*h/mL Interval 251122.0 to 329379.0	652747 mcg*h/mL Interval 630464.0 to 704177.0	1294774 mcg*h/mL Interval 996669.0 to 1315203.0	96329 mcg*h/mL Interval 79956.0 to 112703.0	287567 mcg*h/mL Interval 159477.0 to 415464.0	588913 mcg*h/mL Interval 546849.0 to 656664.0	1182466 mcg*h/mL Interval 1136975.0 to 1227957.0	700805 mcg*h/mL Interval 700805.0 to 1041499.0	—	—	—	—	—	—	—

SECONDARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

t1/2 is defined as the time measured for the plasma concentration to decrease by 1 half to its original concentration of M254. Baseline was the predose sample. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. In Part C, combined data of both arms of Group 1 is presented as planned.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=7 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=2 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=5 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=1 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period n=10 Participants Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Apparent Terminal Phase Half-life (t1/2) of M254	NA hours 'NA' signifies that the median and full range (lower and upper limits) data could not be calculated due to insufficient data available for reliable parameter calculation.	466 hours Interval 239.0 to 488.0	463 hours Interval 412.0 to 520.0	517 hours Interval 405.0 to 530.0	609 hours Interval 565.0 to 679.0	659 hours Interval 468.0 to 660.0	548 hours Interval 493.0 to 762.0	387 hours Interval 383.0 to 390.0	478 hours Interval 427.0 to 525.0	437 hours Interval 399.0 to 595.0	467 hours Interval 467.0 to 467.0	391 hours Interval 254.0 to 696.0	—	—	—	—	—	—	—

SECONDARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

Vz is defined as volume of distribution of M254 at terminal phase. Baseline was the predose sample. Data for this outcome measure was not planned for pooled placebo arm in Part A and thus no data was presented for placebo arm in Part A. In Part C, combined data of both arms of Group 1 is presented as planned.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=3 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=2 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=4 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=1 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=10 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Volume of Distribution (Vz) of M254	6481 milliliter (mL) Interval 6274.0 to 7719.0	6129 milliliter (mL) Interval 5944.0 to 7396.0	5447 milliliter (mL) Interval 4445.0 to 8066.0	7105 milliliter (mL) Interval 6668.0 to 7151.0	6383 milliliter (mL) Interval 4960.0 to 6468.0	6419 milliliter (mL) Interval 6087.0 to 9920.0	8679 milliliter (mL) Interval 7487.0 to 9871.0	5259 milliliter (mL) Interval 5197.0 to 5321.0	7258 milliliter (mL) Interval 4907.0 to 7967.0	9623 milliliter (mL) Interval 9623.0 to 9623.0	6059 milliliter (mL) Interval 2485.0 to 8707.0	—	—	—	—	—	—	—	—

SECONDARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

CL is defined as clearance of M254, calculated as dose/AUC(0-infinity). Baseline was the predose sample. Data for this outcome measure was not planned for pooled placebo arm in Part A and thus no data was presented for placebo arm in Part A. In Part C, combined data of both arms of Group 1 is presented as planned.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=3 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=2 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=4 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=1 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=10 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Clearance (CL) of M254	9.63 milliliters per hour (mL/h) Interval 8.92 to 22.4	9.85 milliliters per hour (mL/h) Interval 8.89 to 10.3	7.62 milliliters per hour (mL/h) Interval 7.3 to 10.5	7.59 milliliters per hour (mL/h) Interval 7.3 to 8.71	6.79 milliliters per hour (mL/h) Interval 5.22 to 9.46	7.69 milliliters per hour (mL/h) Interval 5.84 to 14.0	15.6 milliliters per hour (mL/h) Interval 13.3 to 17.9	12.0 milliliters per hour (mL/h) Interval 8.64 to 20.2	9.69 milliliters per hour (mL/h) Interval 7.79 to 11.7	14.3 milliliters per hour (mL/h) Interval 14.3 to 14.3	10.1 milliliters per hour (mL/h) Interval 6.77 to 12.5	—	—	—	—	—	—	—	—

SECONDARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

Mean residence time is the average time that drug dose remained in the body. Baseline was the predose sample. Data for this outcome measure was not planned for pooled placebo arm in Part A and thus no data was presented for placebo arm in Part A. In Part C, combined data of both arms of Group 1 is presented as planned.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=3 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=2 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=4 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=1 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=10 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Mean Residence Time (MRT) of M254	570 hours Standard Deviation 190	654 hours Standard Deviation 75.9	676 hours Standard Deviation 107	867 hours Standard Deviation 79.8	820 hours Standard Deviation 163	818 hours Standard Deviation 189	517 hours Standard Deviation NA 'NA' signifies that the standard deviation was not calculated as planned when the total number of participants analyzed for a treatment was lower than 3.	661 hours Standard Deviation 77.0	653 hours Standard Deviation 109	610 hours Standard Deviation NA 'NA' signifies that the standard deviation was not calculated as planned when the total number of participants analyzed for a treatment was lower than 3.	584 hours Standard Deviation 177	—	—	—	—	—	—	—	—

SECONDARY outcome

Timeframe: Predose (baseline) up to Day 29 post dose

Population: PK data analysis set included all randomized participants who received at least 1 dose of M254 or IVIg or placebo with at least 4 evaluable data points adequate to create an evaluable plasma concentration profile of M254. Here, N (number of participants analyzed) indicates number of participants evaluable for this outcome measure.

Percentage of the estimated part for the calculation of AUC(0-infinity) (%AUCextra) of M254 were reported. Baseline was the predose sample. Data for this outcome measure was not planned for pooled placebo arm in Part A and thus no data was presented for placebo arm in Part A. In Part C, combined data of both arms of Group 1 is presented as planned.

Outcome measures

Outcome measures
Measure	Part A: Pooled Placebo n=3 Participants All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 Participants Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 Participants Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=2 Participants Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=4 Participants Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=5 Participants Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=1 Participants Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=10 Participants Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1) : M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Parts A, B, and C: Percentage of the Estimated Part for the Calculation of AUC(0-infinity) (%AUCextra) of M254	46.3 Percentage of AUC(0-infinity) Interval 24.1 to 48.3	45.1 Percentage of AUC(0-infinity) Interval 41.9 to 49.8	49.8 Percentage of AUC(0-infinity) Interval 39.5 to 50.0	51.9 Percentage of AUC(0-infinity) Interval 49.7 to 57.8	46.5 Percentage of AUC(0-infinity) Interval 34.5 to 47.9	40.1 Percentage of AUC(0-infinity) Interval 36.5 to 50.6	27.2 Percentage of AUC(0-infinity) Interval 27.1 to 27.2	37.0 Percentage of AUC(0-infinity) Interval 31.9 to 43.4	31.9 Percentage of AUC(0-infinity) Interval 29.9 to 41.1	33.2 Percentage of AUC(0-infinity) Interval 33.2 to 33.2	27.6 Percentage of AUC(0-infinity) Interval 17.5 to 50.3	—	—	—	—	—	—	—	—

Deaths: 0 deaths

Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period

Serious events: 0 serious events

Other events: 2 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Part A: Pooled Placebo n=7 participants at risk All healthy participants of Part A received a single intravenous (IV) infusion of matching placebo on Day 1.	Part A: M254 3 Milligrams/Kilogram (mg/kg) n=3 participants at risk Healthy participants received a single IV infusion of M254 3 mg/kg on Day 1.	Part A: M254 10 mg/kg n=3 participants at risk Healthy participants received a single IV infusion of M254 10 mg/kg on Day 1.	Part A: M254 30 mg/kg n=3 participants at risk Healthy participants received a single IV infusion of M254 30 mg/kg on Day 1.	Part A: M254 60 mg/kg n=3 participants at risk Healthy participants received a single IV infusion of M254 60 mg/kg on Day 1.	Part A: M254 120 mg/kg n=3 participants at risk Healthy participants received a single IV infusion of M254 120 mg/kg on Day 1.	Part A: M254 250 mg/kg n=3 participants at risk Healthy participants received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 20 mg/kg - M254 Period n=2 participants at risk Participants with immune thrombocytopenia purpura (ITP) received a single intravenous (IV) infusion of M254 20 mg/kg on Day 1.	Part B: M254 20 mg/kg - IVIg Period n=2 participants at risk Participants with ITP received a single IV infusion of IV immunoglobulin (IVIg) 1000 mg/kg on Day 29.	Part B: M254 60 mg/kg - M254 Period n=5 participants at risk Participants with ITP received a single IV infusion of M254 60 mg/kg on Day 1.	Part B: M254 60 mg/kg - IVIg Period n=4 participants at risk Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 120 mg/kg - M254 Period n=5 participants at risk Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part B: M254 120 mg/kg - IVIg Period n=3 participants at risk Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part B: M254 250 mg/kg - M254 Period n=2 participants at risk Participants with ITP received a single IV infusion of M254 250 mg/kg on Day 1.	Part B: M254 250 mg/kg - IVIg Period n=2 participants at risk Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - M254 Period n=6 participants at risk Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 1.	Part C (Group 1): M254 120 mg/kg and IVIg 1000 mg/kg - IVIg Period n=5 participants at risk Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 29.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - IVIg Period n=5 participants at risk Participants with ITP received a single IV infusion of IVIg 1000 mg/kg on Day 1.	Part C (Group 1): IVIg 1000 mg/kg and M254 120 mg/kg - M254 Period n=5 participants at risk Participants with ITP received a single IV infusion of M254 120 mg/kg on Day 29.
Musculoskeletal and connective tissue disorders Back Pain	14.3% 1/7 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Musculoskeletal and connective tissue disorders Bone Pain	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Musculoskeletal and connective tissue disorders Myalgia	14.3% 1/7 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Musculoskeletal and connective tissue disorders Pain in Extremity	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	16.7% 1/6 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Nervous system disorders Dizziness	14.3% 1/7 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Nervous system disorders Headache	42.9% 3/7 • Number of events 4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	100.0% 3/3 • Number of events 3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	66.7% 2/3 • Number of events 3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	100.0% 3/3 • Number of events 3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	50.0% 2/4 • Number of events 2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Renal and urinary disorders Pollakiuria	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Reproductive system and breast disorders Dysmenorrhoea	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Respiratory, thoracic and mediastinal disorders Cough	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	25.0% 1/4 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Catheter Site Related Reaction	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Blood and lymphatic system disorders Neutropenia	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Blood and lymphatic system disorders Thrombocytopenia	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Gastrointestinal disorders Abdominal Pain	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	25.0% 1/4 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Gastrointestinal disorders Constipation	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Gastrointestinal disorders Diarrhoea	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Gastrointestinal disorders Dyspepsia	14.3% 1/7 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Gastrointestinal disorders Faeces Soft	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Gastrointestinal disorders Nausea	42.9% 3/7 • Number of events 3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	25.0% 1/4 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Gastrointestinal disorders Vomiting	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	50.0% 2/4 • Number of events 3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Catheter Site Bruise	14.3% 1/7 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Catheter Site Haematoma	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Chills	14.3% 1/7 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Fatigue	14.3% 1/7 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Feeling Hot	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	25.0% 1/4 • Number of events 2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Influenza Like Illness	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Infusion Site Haematoma	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Infusion Site Reaction	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Infusion Site Swelling	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Medical Device Site Irritation	14.3% 1/7 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Oedema Peripheral	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	25.0% 1/4 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Pyrexia	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Vessel Puncture Site Bruise	14.3% 1/7 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Vessel Puncture Site Haematoma	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
General disorders Vessel Puncture Site Reaction	14.3% 1/7 • Number of events 2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Infections and infestations Bronchitis	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Infections and infestations Cystitis	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Infections and infestations Nasopharyngitis	57.1% 4/7 • Number of events 5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Infections and infestations Upper Respiratory Tract Infection	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Injury, poisoning and procedural complications Contusion	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Injury, poisoning and procedural complications Infusion Related Reaction	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Injury, poisoning and procedural complications Limb Injury	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Injury, poisoning and procedural complications Road Traffic Accident	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Investigations Platelet Count Decreased	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	50.0% 1/2 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Metabolism and nutrition disorders Decreased Appetite	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Metabolism and nutrition disorders Iron Deficiency	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Metabolism and nutrition disorders Vitamin B12 Deficiency	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Respiratory, thoracic and mediastinal disorders Epistaxis	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Respiratory, thoracic and mediastinal disorders Nasal Congestion	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Respiratory, thoracic and mediastinal disorders Nasal Dryness	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Respiratory, thoracic and mediastinal disorders Rhinorrhoea	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	25.0% 1/4 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Skin and subcutaneous tissue disorders Dermatitis Contact	14.3% 1/7 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Skin and subcutaneous tissue disorders Dry Skin	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Skin and subcutaneous tissue disorders Skin Irritation	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Vascular disorders Flushing	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	33.3% 1/3 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.
Vascular disorders Hypertension	0.00% 0/7 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/4 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/3 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/2 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/6 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	20.0% 1/5 • Number of events 1 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.	0.00% 0/5 • From Day 1 up to Day 29 The safety analysis set included all participants who received at least 1 dose of M254 or IVIg or placebo. Data was planned to be collected and analyzed on pooled population of participants who received placebo in Part A. For Parts B and C, treatment period wise AE data were presented.

Additional Information

Senior Director Clinical Development Head Rheumatology

Momenta Pharmaceuticals, Inc.

Phone: 844-434-4210

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee The results of this study may be published or presented at scientific meetings. If this is foreseen, the Investigator agrees to submit all manuscripts or abstracts to the sponsor before submission. This allows the sponsor to protect proprietary information and to provide comments.
Publication restrictions are in place

Restriction type: OTHER