A Safety, Tolerability, and Immunogenicity Study of mRNA-1345 and mRNA-1365 in Participants Aged 5 Months to <24 Months

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NCT05743881 · readout in 1,108 d

Sponsored by ModernaTX, Inc. (industry) · MRNA — their whole pipeline →.

Phase

Phase 1

Status

Active, not recruiting

Study type

Interventional

Design

Randomized · Triple · Treatment

Enrollment

186actual

Sites

Countries

Panama, United Kingdom, United States

Every value on this page is a field the sponsor filed with ClinicalTrials.gov, reproduced. Dates are their own estimates, revised as a study runs, unless the registry marks them actual. sources →

Source: ClinicalTrials.gov, retrieved 2026-08-19

Dates

each axis at the precision it was filed, with the registry's own basis

Date

Filed

Basis

What it is

Start

2023-02-15

actual

When the study began enrolling

Primary completion

2029-08-31

estimated

The date the last participant is measured for the primary outcome — the readout window

Study completion

2029-08-31

estimated

The whole study's end, after follow-up

First posted

2023-02-24

actual

When this record first appeared on the registry

Results posted

—

When the sponsor posted results to the registry

Record updated

2026-06-26

actual

The sponsor's own last edit to this record — every projection above is as current as this date

What it studies

Conditions

Respiratory Syncytial Virus
Human Metapneumovirus

Interventions

Biological: mRNA-1345
Biological: mRNA-1365
Biological: Placebo
Drug: Nimenrix

Primary outcomes

what the primary-completion date above is the date OF

Main Study: Number of Participants with Solicited Local and Systemic Adverse Reactions (ARs)

measured Up to Day 120 (7 days after each injection)

Main Study: Number of Participants with Unsolicited Adverse Events (AEs)

measured Up to Day 141 (28 days after each injection)

Main Study: Number of Participants with Medically-Attended Adverse Events (MAAEs)

measured Day 1 through Day 730

Main Study: Number of Participants with Adverse Event of Special Interests (AESIs), Serious Adverse Events (SAEs) and Adverse Events Leading to Discontinuation

measured Day 1 through Day 730

Part B Extension: Number of Participants with MAAEs, AESIs and SAEs

measured Day 1 of the Extension to end of study (EoS) (up to 3 years)

Part B Extension: Number of Participants with Lower Respiratory Tract Illness (LRTI), Severe LRTI, Very Severe LRTI, and Hospitalizations Associated with RSV or hMPV

measured Day 1 of the Extension to EoS (up to 3 years)

Publications

PMID 39608233 — linked by the registry

Linked on the registry record. A “linked by the registry” entry is NLM's own automated PubMed match, not a claim by the sponsor that the paper reports this study.

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