Trial Outcomes & Findings for Study to Evaluate the Safety, Reactogenicity, and Effectiveness of mRNA-1273.214 SARS-CoV-2 (COVID-19) Vaccine in Infants (NCT NCT05584202)

Last Updated: 2025-11-26

Results Overview

Solicited ARs (local and systemic) were collected in an electronic diary (eDiary). Local ARs included injection site pain/tenderness, injection site erythema (redness), injection site swelling/induration (hardness), and groin or underarm swelling or tenderness ipsilateral to the side of injection. Systemic ARs included fever, irritability/crying, sleepiness, and loss of appetite. Solicited AR severity was graded according to a modified version (relevant to age 12 weeks to \<6 months) of the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventative Vaccine Clinical Trials. ARs graded 1-4 are presented. Lower scores indicated lower severity, and higher scores indicated greater severity. A summary of serious adverse events (SAEs) and nonserious adverse events (AEs) (Safety Set), regardless of causality, is located in the AE section.

Recruitment status

TERMINATED

Study phase

PHASE2

Target enrollment

68 participants

Primary outcome timeframe

Day 1 up to 7 days after first vaccination (up to Day 8)

Results posted on

2025-11-26

Participant Flow

Participants eligible for enrollment in Part 1 of this study included male and female infants aged 12 weeks to \<6 months at the time of administration of first dose who were in good general health.

Participant milestones

Participant milestones
Measure	mRNA-1273.214 5 μg Participants received at least 1 of the 2 doses of mRNA-1273.214 5 micrograms (μg) by intramuscular (IM) injection approximately 8 weeks apart (Day 1 and Day 57).	mRNA-1273.214 10 μg Participants received at least 1 of the 2 doses of mRNA-1273.214 10 μg by IM injection approximately 8 weeks apart (Day 1 and Day 57).
Overall Study STARTED	50	18
Overall Study Received First Injection	50	18
Overall Study Received Second Injection	49	15
Overall Study Safety Set	50	18
Overall Study Solicited Safety Set First Injection	50	18
Overall Study Solicited Safety Set Second Injection	49	15
Overall Study Per-Protocol Immunogenicity Set (PPIS)	37	11
Overall Study COMPLETED	45	14
Overall Study NOT COMPLETED	5	4

Reasons for withdrawal

Reasons for withdrawal
Measure	mRNA-1273.214 5 μg Participants received at least 1 of the 2 doses of mRNA-1273.214 5 micrograms (μg) by intramuscular (IM) injection approximately 8 weeks apart (Day 1 and Day 57).	mRNA-1273.214 10 μg Participants received at least 1 of the 2 doses of mRNA-1273.214 10 μg by IM injection approximately 8 weeks apart (Day 1 and Day 57).
Overall Study Withdrawal of Consent	3	2
Overall Study Lost to Follow-up	2	1
Overall Study Death	0	1

Baseline Characteristics

Study to Evaluate the Safety, Reactogenicity, and Effectiveness of mRNA-1273.214 SARS-CoV-2 (COVID-19) Vaccine in Infants

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	mRNA-1273.214 5 μg n=50 Participants Participants received at least 1 of 2 doses of mRNA-1273.214 5 μg by IM injection approximately 8 weeks apart (Day 1 and Day 57).	mRNA-1273.214 10 μg n=18 Participants Participants received at least 1 of 2 doses of mRNA-1273.214 10 μg by IM injection approximately 8 weeks apart (Day 1 and Day 57).	Total n=68 Participants Total of all reporting groups
Age, Customized In utero	0 Participants n=492 Participants	0 Participants n=492 Participants	0 Participants n=984 Participants
Age, Customized Preterm newborn infants (gestational age < 37 wks)	0 Participants n=492 Participants	0 Participants n=492 Participants	0 Participants n=984 Participants
Age, Customized Newborns (0-27 days)	0 Participants n=492 Participants	0 Participants n=492 Participants	0 Participants n=984 Participants
Age, Customized Infants and toddlers (28 days-23 months)	50 Participants n=492 Participants	18 Participants n=492 Participants	68 Participants n=984 Participants
Age, Customized Children (2-11 years)	0 Participants n=492 Participants	0 Participants n=492 Participants	0 Participants n=984 Participants
Age, Customized Adolescents (12-17 years)	0 Participants n=492 Participants	0 Participants n=492 Participants	0 Participants n=984 Participants
Age, Customized Adults (18-64 years)	0 Participants n=492 Participants	0 Participants n=492 Participants	0 Participants n=984 Participants
Age, Customized From 65-84 years	0 Participants n=492 Participants	0 Participants n=492 Participants	0 Participants n=984 Participants
Age, Customized 85 years and over	0 Participants n=492 Participants	0 Participants n=492 Participants	0 Participants n=984 Participants
Sex: Female, Male Female	26 Participants n=492 Participants	4 Participants n=492 Participants	30 Participants n=984 Participants
Sex: Female, Male Male	24 Participants n=492 Participants	14 Participants n=492 Participants	38 Participants n=984 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	12 Participants n=492 Participants	6 Participants n=492 Participants	18 Participants n=984 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	38 Participants n=492 Participants	12 Participants n=492 Participants	50 Participants n=984 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=492 Participants	0 Participants n=492 Participants	0 Participants n=984 Participants
Race/Ethnicity, Customized Race · White	35 Participants n=492 Participants	9 Participants n=492 Participants	44 Participants n=984 Participants
Race/Ethnicity, Customized Race · Black or African American	13 Participants n=492 Participants	5 Participants n=492 Participants	18 Participants n=984 Participants
Race/Ethnicity, Customized Race · Asian	1 Participants n=492 Participants	0 Participants n=492 Participants	1 Participants n=984 Participants
Race/Ethnicity, Customized Race · Multiracial	1 Participants n=492 Participants	4 Participants n=492 Participants	5 Participants n=984 Participants

PRIMARY outcome

Timeframe: Day 1 up to 7 days after first vaccination (up to Day 8)

Population: Solicited Safety Set (First Injection) included participants who received the first injection of study drug and contributed any solicited AR data.

Outcome measures

Outcome measures
Measure	mRNA-1273.214 5 μg First Injection (Solicited Safety Set) n=50 Participants Participants received first injection of mRNA-1273.214 5 μg.	mRNA-1273.214 10 μg First Injection (Solicited Safety Set) n=18 Participants Participants received first injection of mRNA-1273.214 10 μg.
Number of Participants With Solicited Local and Systemic Adverse Reactions (ARs) After First Injection Grade 1	23 Participants	7 Participants
Number of Participants With Solicited Local and Systemic Adverse Reactions (ARs) After First Injection Grade 2	8 Participants	3 Participants
Number of Participants With Solicited Local and Systemic Adverse Reactions (ARs) After First Injection Grade 3	1 Participants	0 Participants
Number of Participants With Solicited Local and Systemic Adverse Reactions (ARs) After First Injection Grade 4	0 Participants	0 Participants
Number of Participants With Solicited Local and Systemic Adverse Reactions (ARs) After First Injection Any solicited ARs (Grade 1-4)	32 Participants	10 Participants

PRIMARY outcome

Timeframe: Day 57 up to 7 days after second vaccination (up to Day 64)

Population: Solicited Safety Set (Second Injection) included participants who received the second injection of study drug and contributed any solicited AR data.

Solicited ARs (local and systemic) were collected in eDiary. Local ARs included injection site pain/tenderness, injection site erythema (redness), injection site swelling/induration (hardness), and groin or underarm swelling or tenderness ipsilateral to the side of injection. Systemic ARs included fever, irritability/crying, sleepiness, and loss of appetite. Solicited AR severity was graded according to a modified version (relevant to age 12 weeks to \<6 months) of the Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventative Vaccine Clinical Trials. ARs graded 1-4 are presented. Lower scores indicated lower severity, and higher scores indicated greater severity. A summary of SAEs and nonserious AEs (Safety Set), regardless of causality, is located in the AE section.

Outcome measures

Outcome measures
Measure	mRNA-1273.214 5 μg First Injection (Solicited Safety Set) n=49 Participants Participants received first injection of mRNA-1273.214 5 μg.	mRNA-1273.214 10 μg First Injection (Solicited Safety Set) n=15 Participants Participants received first injection of mRNA-1273.214 10 μg.
Number of Participants With Solicited Local and Systemic ARs After Second Injection Grade 1	18 Participants	6 Participants
Number of Participants With Solicited Local and Systemic ARs After Second Injection Grade 2	7 Participants	2 Participants
Number of Participants With Solicited Local and Systemic ARs After Second Injection Grade 3	1 Participants	0 Participants
Number of Participants With Solicited Local and Systemic ARs After Second Injection Grade 4	0 Participants	0 Participants
Number of Participants With Solicited Local and Systemic ARs After Second Injection Any solicited ARs (Grade 1-4)	26 Participants	8 Participants

PRIMARY outcome

Timeframe: Day 1 up to 28 days after any vaccination (up to Day 85)

Population: Safety Set included participants who received at least 1 dose of study drug.

An unsolicited AE was any AE reported by the participant that was not specified as a solicited AR in the protocol or was specified as a solicited AR but started outside the protocol-defined period for reporting solicited ARs (onset after Day 7 of dosing). An AE was defined as any untoward medical occurrence associated with the use of a drug in humans, whether or not considered drug related. Any abnormal laboratory test result or other safety assessment, including one that worsened from baseline and was considered clinically significant by the Investigator was recorded as an AE. A summary of SAEs and nonserious AEs (Safety Set), regardless of causality, is located in the AE section. COVID-19/SARS-CoV-2 infections were considered clinical events and not AEs.

Outcome measures

Outcome measures
Measure	mRNA-1273.214 5 μg First Injection (Solicited Safety Set) n=50 Participants Participants received first injection of mRNA-1273.214 5 μg.	mRNA-1273.214 10 μg First Injection (Solicited Safety Set) n=18 Participants Participants received first injection of mRNA-1273.214 10 μg.
Number of Participants With Unsolicited Adverse Events (AEs) After Any Injection	24 Participants	8 Participants

PRIMARY outcome

Timeframe: Day 1 up to Day 422

Population: Safety Set included participants who received at least 1 dose of study drug.

SAE was defined as any AE that resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in disability/permanent damage, was a congenital anomaly/birth defect, or was an important medical event. AESIs were identified based upon medical concepts that may be related to COVID-19 or were of interest in COVID-19 vaccine safety surveillance. MAAE was an AE that led to an unscheduled visit to a healthcare practitioner, included visits to a study site for unscheduled assessments (for example, abnormal laboratory follow-up, and visits to healthcare practitioners external to the study site \[for example, urgent care, primary care physician\]). A summary of SAEs and nonserious AEs (Safety Set), regardless of causality, is located in the AE section. COVID-19/SARS-CoV-2 infections were considered clinical events and not AEs.

Outcome measures

Outcome measures
Measure	mRNA-1273.214 5 μg First Injection (Solicited Safety Set) n=50 Participants Participants received first injection of mRNA-1273.214 5 μg.	mRNA-1273.214 10 μg First Injection (Solicited Safety Set) n=18 Participants Participants received first injection of mRNA-1273.214 10 μg.
Number of Participants With SAEs, AEs of Special Interest (AESIs), Medically Attended AEs (MAAEs), and AEs Leading to Study or Treatment Discontinuation SAEs	1 Participants	1 Participants
Number of Participants With SAEs, AEs of Special Interest (AESIs), Medically Attended AEs (MAAEs), and AEs Leading to Study or Treatment Discontinuation AESIs	1 Participants	0 Participants
Number of Participants With SAEs, AEs of Special Interest (AESIs), Medically Attended AEs (MAAEs), and AEs Leading to Study or Treatment Discontinuation MAAEs	39 Participants	16 Participants
Number of Participants With SAEs, AEs of Special Interest (AESIs), Medically Attended AEs (MAAEs), and AEs Leading to Study or Treatment Discontinuation AEs Leading to Study or Treatment Discontinuation	0 Participants	1 Participants

SECONDARY outcome

Timeframe: Baseline and 28 days after second dose (Day 85)

Population: PPIS: participants who received the planned doses of investigational product per schedule, complied with immunogenicity testing schedule, had Baseline (Day 1) and Day 85 antibody assessments, and had no major protocol deviations that impacted key or critical data.

Pseudovirus nAb were measured using pseudovirus neutralization assay (PsVNA). Antibody values reported as below the lower limit of quantification (LLOQ) were replaced by 0.5\*LLOQ. Values greater than the upper limit of quantification (ULOQ) were replaced by the ULOQ if actual values were not available. VAC122 nAb against the SARS-CoV-2 B.1.1.529 variant (LLOQ: 8 arbitrary unit (AU)/milliliter (mL), ULOQ: 24503 AU/mL).

Outcome measures

Outcome measures
Measure	mRNA-1273.214 5 μg First Injection (Solicited Safety Set) n=37 Participants Participants received first injection of mRNA-1273.214 5 μg.	mRNA-1273.214 10 μg First Injection (Solicited Safety Set) n=11 Participants Participants received first injection of mRNA-1273.214 10 μg.
Geometric Mean Concentration (GMC) of Serum Pseudovirus Neutralizing Antibod (nAb) Titers Against SARS-CoV-2 Omicron BA.1 Variant (B.1.1.529) After Second Dose of mRNA-1273.214 Baseline	64.9 AU/mL Interval 42.3 to 99.6	84.2 AU/mL Interval 42.8 to 165.5
Geometric Mean Concentration (GMC) of Serum Pseudovirus Neutralizing Antibod (nAb) Titers Against SARS-CoV-2 Omicron BA.1 Variant (B.1.1.529) After Second Dose of mRNA-1273.214 Day 85	163.0 AU/mL Interval 91.0 to 292.2	228.6 AU/mL Interval 97.0 to 538.9

SECONDARY outcome

Timeframe: Baseline and 28 days after second dose (Day 85)

Pseudovirus nAb were measured using PsVNA assay. Antibody values reported as below the LLOQ were replaced by 0.5\*LLOQ. Values greater than the ULOQ were replaced by the ULOQ if actual values were not available. VAC62 Neutralizing Antibody against D614G (LLOQ: 10 AU/mL, ULOQ: 111433 AU/mL).

Outcome measures

Outcome measures
Measure	mRNA-1273.214 5 μg First Injection (Solicited Safety Set) n=37 Participants Participants received first injection of mRNA-1273.214 5 μg.	mRNA-1273.214 10 μg First Injection (Solicited Safety Set) n=11 Participants Participants received first injection of mRNA-1273.214 10 μg.
GMC of Serum Pseudovirus nAb Titers Against SARS-CoV-2 Original Strain (D614G) After Second Dose of mRNA-1273.214 Baseline	236.4 AU/mL Interval 150.8 to 370.6	203.6 AU/mL Interval 76.6 to 540.9
GMC of Serum Pseudovirus nAb Titers Against SARS-CoV-2 Original Strain (D614G) After Second Dose of mRNA-1273.214 Day 85	178.1 AU/mL Interval 133.3 to 237.9	96.0 AU/mL Interval 72.2 to 127.6

Adverse Events

mRNA-1273.214 5 ug

Serious events: 1 serious events

Other events: 40 other events

Deaths: 0 deaths

mRNA-1273.214 10 ug

Serious events: 1 serious events

Other events: 16 other events

Deaths: 1 deaths

Serious adverse events

Serious adverse events
Measure	mRNA-1273.214 5 ug n=50 participants at risk Participants received at least 1 of 2 doses of mRNA-1273.214 5 μg by IM injection approximately 8 weeks apart (Day 1 and Day 57).	mRNA-1273.214 10 ug n=18 participants at risk Participants received at least 1 of 2 doses of mRNA-1273.214 10 μg by IM injection approximately 8 weeks apart (Day 1 and Day 57).
Cardiac disorders Cardiac arrest	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
General disorders Drowning	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Rhinovirus infection	2.0% 1/50 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	0.00% 0/18 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Nervous system disorders Hypoxic-ischaemic encephalopathy	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.

Other adverse events

Additional Information

Moderna WeCare Team

ModernaTX, Inc.

Phone: 866-663-3762

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place

Measure	mRNA-1273.214 5 ug n=50 participants at risk Participants received at least 1 of 2 doses of mRNA-1273.214 5 μg by IM injection approximately 8 weeks apart (Day 1 and Day 57).	mRNA-1273.214 10 ug n=18 participants at risk Participants received at least 1 of 2 doses of mRNA-1273.214 10 μg by IM injection approximately 8 weeks apart (Day 1 and Day 57).
Infections and infestations Otosalpingitis	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Pneumonia	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Respiratory syncytial virus bronchiolitis	2.0% 1/50 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Respiratory syncytial virus infection	14.0% 7/50 • Number of events 7 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	11.1% 2/18 • Number of events 2 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Rhinitis	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Rhinovirus infection	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 3 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Upper respiratory tract infection	32.0% 16/50 • Number of events 39 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	38.9% 7/18 • Number of events 12 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Viral upper respiratory tract infection	18.0% 9/50 • Number of events 23 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	22.2% 4/18 • Number of events 12 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Injury, poisoning and procedural complications Arthropod bite	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Investigations Blood lead increased	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Metabolism and nutrition disorders Decreased appetite	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Nervous system disorders Speech disorder developmental	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Respiratory, thoracic and mediastinal disorders Bronchial hyperreactivity	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Respiratory, thoracic and mediastinal disorders Cough	10.0% 5/50 • Number of events 7 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	16.7% 3/18 • Number of events 8 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Gastroenteritis	6.0% 3/50 • Number of events 4 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	0.00% 0/18 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Gastroenteritis viral	6.0% 3/50 • Number of events 3 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	11.1% 2/18 • Number of events 3 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Hand-foot-and-mouth disease	8.0% 4/50 • Number of events 4 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	11.1% 2/18 • Number of events 2 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Influenza	4.0% 2/50 • Number of events 2 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	11.1% 2/18 • Number of events 2 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Otitis media	24.0% 12/50 • Number of events 17 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	16.7% 3/18 • Number of events 9 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Otitis media acute	18.0% 9/50 • Number of events 14 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	22.2% 4/18 • Number of events 10 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Ear and labyrinth disorders Otorrhoea	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Gastrointestinal disorders Constipation	6.0% 3/50 • Number of events 4 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Gastrointestinal disorders Diarrhoea	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Gastrointestinal disorders Gastrooesophageal reflux disease	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Gastrointestinal disorders Teething	12.0% 6/50 • Number of events 6 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Gastrointestinal disorders Vomiting	2.0% 1/50 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
General disorders Pyrexia	10.0% 5/50 • Number of events 5 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	11.1% 2/18 • Number of events 4 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Beta haemolytic streptococcal infection	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Bronchiolitis	12.0% 6/50 • Number of events 7 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Candida nappy rash	6.0% 3/50 • Number of events 3 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Conjunctivitis	4.0% 2/50 • Number of events 2 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 2 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Conjunctivitis bacterial	8.0% 4/50 • Number of events 4 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	16.7% 3/18 • Number of events 4 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Coronavirus infection	0.00% 0/50 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Infections and infestations Ear infection	6.0% 3/50 • Number of events 6 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 2 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Respiratory, thoracic and mediastinal disorders Nasal congestion	10.0% 5/50 • Number of events 5 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	11.1% 2/18 • Number of events 3 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Respiratory, thoracic and mediastinal disorders Rhinitis allergic	2.0% 1/50 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Respiratory, thoracic and mediastinal disorders Rhinorrhoea	6.0% 3/50 • Number of events 4 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	0.00% 0/18 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Skin and subcutaneous tissue disorders Dermatitis atopic	4.0% 2/50 • Number of events 2 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	5.6% 1/18 • Number of events 1 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.
Skin and subcutaneous tissue disorders Eczema	10.0% 5/50 • Number of events 5 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.	0.00% 0/18 • Day 1 up to Day 422 Safety Set included participants who received at least 1 dose of study drug.