Trial Outcomes & Findings for A Study of a Single Subcutaneous Dose of ALXN1210 in Healthy Adult Participants (NCT NCT05288829)

Last Updated: 2023-05-01

Results Overview

An adverse event (AE) was defined as any unfavorable and unintended sign (for example, including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal product or procedure, whether or not considered related to the medicinal product or procedure, which occurred during the course of the clinical study. TEAEs were defined as AEs with a start date or time on or after the first dose of the study drug. A summary of all Serious Adverse Events and Other Adverse Events (nonserious) regardless of causality is located in the 'Reported Adverse Events' Section.

Recruitment status

COMPLETED

Study phase

PHASE1

Target enrollment

42 participants

Primary outcome timeframe

Baseline up to Day 200

Results posted on

2023-05-01

Participant Flow

Of the 161 screened participants, 42 were randomly assigned to receive study drug: Placebo subcutaneous (SC), ALXN1210 400 milligrams (mg) SC, or ALXN1210 400 mg intravenous (IV).

Participant milestones

Participant milestones
Measure	ALXN1210 400 mg SC Participants received a single dose of ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.	ALXN1210 400 mg IV Participants received a single dose of ALXN1210 400 mg via IV infusion on Day 1. Participants were followed for 200 days.	Placebo SC Participants received a single dose of placebo matched to ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.
Overall Study STARTED	24	12	6
Overall Study Received At Least 1 Dose Of Study Drug	24	12	6
Overall Study COMPLETED	24	12	6
Overall Study NOT COMPLETED	0	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

A Study of a Single Subcutaneous Dose of ALXN1210 in Healthy Adult Participants

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	ALXN1210 400 mg SC n=24 Participants Participants received a single dose of ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.	ALXN1210 400 mg IV n=12 Participants Participants received a single dose of ALXN1210 400 mg via IV infusion on Day 1. Participants were followed for 200 days.	Placebo SC n=6 Participants Participants received a single dose of placebo matched to ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.	Total n=42 Participants Total of all reporting groups
Age, Continuous	36.2 years STANDARD_DEVIATION 7.73 • n=5 Participants	33.2 years STANDARD_DEVIATION 8.20 • n=7 Participants	34.2 years STANDARD_DEVIATION 6.46 • n=5 Participants	35.0 years STANDARD_DEVIATION 7.65 • n=4 Participants
Sex: Female, Male Female	8 Participants n=5 Participants	4 Participants n=7 Participants	2 Participants n=5 Participants	14 Participants n=4 Participants
Sex: Female, Male Male	16 Participants n=5 Participants	8 Participants n=7 Participants	4 Participants n=5 Participants	28 Participants n=4 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	1 Participants n=5 Participants	1 Participants n=7 Participants	0 Participants n=5 Participants	2 Participants n=4 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	23 Participants n=5 Participants	11 Participants n=7 Participants	6 Participants n=5 Participants	40 Participants n=4 Participants
Ethnicity (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
Race/Ethnicity, Customized Asian	2 participants n=5 Participants	2 participants n=7 Participants	1 participants n=5 Participants	5 participants n=4 Participants
Race/Ethnicity, Customized Black or African American	5 participants n=5 Participants	0 participants n=7 Participants	1 participants n=5 Participants	6 participants n=4 Participants
Race/Ethnicity, Customized White	17 participants n=5 Participants	10 participants n=7 Participants	2 participants n=5 Participants	29 participants n=4 Participants
Race/Ethnicity, Customized Other	0 participants n=5 Participants	0 participants n=7 Participants	2 participants n=5 Participants	2 participants n=4 Participants

PRIMARY outcome

Timeframe: Baseline up to Day 200

Population: The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).

Outcome measures

Outcome measures
Measure	ALXN1210 400 mg SC n=24 Participants Participants received a single dose of ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.	ALXN1210 400 mg IV n=12 Participants Participants received a single dose of ALXN1210 400 mg via IV infusion on Day 1. Participants were followed for 200 days.	Placebo SC n=6 Participants Participants received a single dose of placebo matched to ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.
Number of Participants With Treatment-Emergent Adverse Events (TEAEs)	19 Participants	11 Participants	5 Participants

PRIMARY outcome

Timeframe: Predose , end of infusion (EOI); 30 minutes post EOI; 2, 4, and 8 hours post start of infusion; and from Day 2 up to Day 150

Population: The pharmacokinetic (PK) population consisted of all participants from the safety population who received either ALXN1210 SC or ALXN1210 IV and who had sufficient serum concentration data to enable the calculation of PK parameters. For this outcome measure, the N includes the participants from both the SC and IV groups.

The absolute bioavailability of ALXN1210 SC is reported as the area under the serum concentration versus time curve from time 0 extrapolated to infinity (AUCinf) geometric mean of the ALXN1210 SC group divided by the AUCinf geometric mean of the ALXN1210 IV group\*100. Linear mixed model with fixed and random effects for the participant was used.

Outcome measures

Outcome measures
Measure	ALXN1210 400 mg SC n=36 Participants Participants received a single dose of ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.	ALXN1210 400 mg IV Participants received a single dose of ALXN1210 400 mg via IV infusion on Day 1. Participants were followed for 200 days.	Placebo SC Participants received a single dose of placebo matched to ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.
Absolute Bioavailability of ALXN1210 SC	60.4 percentage of ratio Interval 49.7 to 73.3	—	—

SECONDARY outcome

Timeframe: Baseline, Day 8

Population: The pharmacodynamic (PD) population consisted of all participants from the safety population who had sufficient total and free C5 concentration data and chicken red blood cells (cRBC) hemolysis data.

Blood samples were collected to determine the percent change in free C5 serum concentration from baseline over time.

Outcome measures

Outcome measures
Measure	ALXN1210 400 mg SC n=24 Participants Participants received a single dose of ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.	ALXN1210 400 mg IV n=12 Participants Participants received a single dose of ALXN1210 400 mg via IV infusion on Day 1. Participants were followed for 200 days.	Placebo SC n=6 Participants Participants received a single dose of placebo matched to ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.
Percent Change From Baseline in Free Complement Protein C5 Concentration At Day 8	-77.08 percent change Standard Deviation 24.481	-98.81 percent change Standard Deviation 0.707	6.40 percent change Standard Deviation 13.397

SECONDARY outcome

Timeframe: Baseline, Day 8

Population: The PD population consisted of all participants from the safety population who had sufficient total and free C5 concentration data and cRBC hemolysis data.

Blood samples were collected to determine the percent change in cRBC from baseline over time.

Outcome measures

Outcome measures
Measure	ALXN1210 400 mg SC n=24 Participants Participants received a single dose of ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.	ALXN1210 400 mg IV n=12 Participants Participants received a single dose of ALXN1210 400 mg via IV infusion on Day 1. Participants were followed for 200 days.	Placebo SC n=6 Participants Participants received a single dose of placebo matched to ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.
Percent Change From Baseline In Chicken Red Blood Cell Hemolysis At Day 8	-29.49 percent change Standard Deviation 33.278	-66.72 percent change Standard Deviation 33.553	-11.14 percent change Standard Deviation 9.330

SECONDARY outcome

Timeframe: Baseline up to Day 200

Population: The immunogenicity analysis population consisted of all participants who had a pre-dose and post-dose ADA sample collected. ADA was data collected for the ALXN1210 arms (SC, IV) only.

Blood samples were collected to evaluate antibody response through development of ADAs. The number of participants who developed ADAs (ADA positive) to ALXN1210 were reported in this outcome measure.

Outcome measures

Outcome measures
Measure	ALXN1210 400 mg SC n=24 Participants Participants received a single dose of ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.	ALXN1210 400 mg IV n=12 Participants Participants received a single dose of ALXN1210 400 mg via IV infusion on Day 1. Participants were followed for 200 days.	Placebo SC Participants received a single dose of placebo matched to ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.
Number of Participants With Positive Antidrug Antibodies (ADAs) to ALXN1210	3 Participants	1 Participants	—

Adverse Events

ALXN1210 400 mg SC

Serious events: 0 serious events

Other events: 19 other events

Deaths: 0 deaths

ALXN1210 400 mg IV

Serious events: 0 serious events

Other events: 11 other events

Deaths: 0 deaths

Placebo SC

Serious events: 0 serious events

Other events: 5 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Additional Information

Alexion Pharmaceuticals, Inc.

Phone: 855-752-2356

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place

Measure	ALXN1210 400 mg SC n=24 participants at risk Participants received a single dose of ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.	ALXN1210 400 mg IV n=12 participants at risk Participants received a single dose of ALXN1210 400 mg via IV infusion on Day 1. Participants were followed for 200 days.	Placebo SC n=6 participants at risk Participants received a single dose of placebo matched to ALXN1210 400 mg via SC infusion on Day 1. Participants were followed for 200 days.
Injury, poisoning and procedural complications Arthropod bite	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Injury, poisoning and procedural complications Joint dislocation	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Immune system disorders Immune system disorders	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Respiratory, thoracic and mediastinal disorders Cough	0.00% 0/24 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	16.7% 2/12 • Number of events 2 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Respiratory, thoracic and mediastinal disorders Nasal congestion	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	8.3% 1/12 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Respiratory, thoracic and mediastinal disorders Allergic sinusitis	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Respiratory, thoracic and mediastinal disorders Oropharyngeal pain	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Nervous system disorders Headache	4.2% 1/24 • Number of events 2 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	25.0% 3/12 • Number of events 3 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	50.0% 3/6 • Number of events 3 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Nervous system disorders Migraine	8.3% 2/24 • Number of events 2 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	8.3% 1/12 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Nervous system disorders Migraine with aura	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
General disorders Vessel puncture site bruise	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Gastrointestinal disorders Diarrhoea	4.2% 1/24 • Number of events 2 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	8.3% 1/12 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	16.7% 1/6 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Gastrointestinal disorders Nausea	0.00% 0/24 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	8.3% 1/12 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	16.7% 1/6 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Gastrointestinal disorders Dyspepsia	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Gastrointestinal disorders Toothache	0.00% 0/24 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	8.3% 1/12 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Gastrointestinal disorders Vomiting	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Skin and subcutaneous tissue disorders Rash papular	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Musculoskeletal and connective tissue disorders Musculoskeletal pain	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	8.3% 1/12 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Musculoskeletal and connective tissue disorders Myalgia	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	8.3% 1/12 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Musculoskeletal and connective tissue disorders Back pain	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Musculoskeletal and connective tissue disorders Pain in extremity	0.00% 0/24 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	8.3% 1/12 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Infections and infestations Nasopharyngitis	45.8% 11/24 • Number of events 13 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	58.3% 7/12 • Number of events 8 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	83.3% 5/6 • Number of events 7 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Infections and infestations Lower respiratory tract infection	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	16.7% 1/6 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Infections and infestations Balanitis candida	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Infections and infestations Cellulitis	0.00% 0/24 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	8.3% 1/12 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Infections and infestations Gastroenteritis	0.00% 0/24 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	16.7% 1/6 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Infections and infestations Tinea pedis	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Infections and infestations Upper respiratory tract infection	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Infections and infestations Viral upper respiratory tract infection	4.2% 1/24 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/12 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/6 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).
Infections and infestations Vulvovaginal candidiasis	0.00% 0/8 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	0.00% 0/4 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).	50.0% 1/2 • Number of events 1 • Baseline up to Day 200 The safety population consisted of all participants who received the protocol-defined, single dose of study drug (ALXN1210 IV, ALXN1210 SC, or placebo SC).