A Study of mRNA-1283 Injection Compared With mRNA-1273 Injection in Participants ≥12 Years of Age to Prevent COVID-19

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NCT05815498 · results posted

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

Phase

Phase 3

Status

Completed

Study type

Interventional

Design

Randomized · Quadruple · Prevention

Enrollment

13,553actual

Sites

230

Countries

Canada, Japan, United Kingdom +1

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

2023-03-28

actual

When the study began enrolling

Primary completion

2025-04-12

actual

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

Study completion

2025-04-12

actual

The whole study's end, after follow-up

First posted

2023-04-18

actual

When this record first appeared on the registry

Results posted

2026-05-01

actual

When the sponsor posted results to the registry

Record updated

2026-05-01

actual

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

What it studies

Condition

COVID-19

Interventions

Biological: mRNA-1283.222
Biological: mRNA-1273.222
Biological: mRNA-1283.815
Biological: mRNA-1273.815

Primary outcomes

what the primary-completion date above is the date OF

Part 1: Geometric Mean (GM) of Omicron BA.4/5 at Day 29

measured Day 29

Part 1: Seroresponse Rate (SRR) Omicron BA.4/5 at Day 29

measured Day 29

Part 1: GM of the Ancestral Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) D614G at Day 29

measured Day 29

Part 1: SRR of Ancestral SARS-CoV-2 D641G at Day 29

measured Day 29

Part 1: Number of Participants With First Event of Centers for Disease Control and Prevention (CDC)-Defined COVID-19

measured From 14 days after injection up to Day 365

Part 1: Number of Participants With Solicited Local and Systemic Adverse Reactions (ARs)

measured Up to Day 7 (7-day follow-up after vaccination)

Part 3: Number of Participants With Solicited Local and Systemic ARs

measured Up to Day 7 (7-day follow-up after vaccination)

Part 1: Number of Participants With Unsolicited Adverse Events (AEs)

measured Up to Day 28 (28-day follow-up after vaccination)

Part 3: Number of Participants With Unsolicited AEs

measured Up to Day 28 (28-day follow-up after vaccination)

Part 1: Number of Participants With Any Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal From Study, and AEs of Special Interest (AESIs)

measured Day 1 up to Day 365

Part 3: Number of Participants With Any SAEs, MAAEs, AEs Leading to Withdrawal From Study, and AESIs

measured Day 1 up to Day 181

Posted documents

hosted by the registry — we link, never re-serve

Study Protocolposted 2023-12-20 · 1.6 MB · Prot_000.pdf

Statistical Analysis Planposted 2025-02-27 · 1.5 MB · SAP_001.pdf

Publications

PMID 40639387 — 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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