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A Study to Evaluate the Efficacy and Safety of mRNA-1283 and mRNA-1273 in Participants 50 to 64 Years of Age Without High-Risk Conditions for Severe Coronavirus Disease 2019 (COVID-19)
NCT07266558 · View on ClinicalTrials.gov ↗
Study Summary
The purpose of this study is to evaluate the efficacy and safety of mRNA-1283 and mRNA-1273 (variant formulations) in adults 50 to 64 years of age without high risk factors for severe COVID-19.
Conditions Studied
Interventions
- BIOLOGICAL Placebo
- BIOLOGICAL mRNA-1273
- BIOLOGICAL mRNA-1283
Study Locations (20)
California
- Avacare — Colton
- CenExel CNR — Garden Grove
- Velocity Clinical Research, Huntington Park — Huntington Park
- Velocity Clinical Research - San Diego - ERN - PPDS-Site Number:8400010 — La Mesa
- Velocity Clinical Research - Los Angeles — Los Angeles
- Artemis Institute for Clinical Research — Riverside
- Peninsula Research Associates — Rolling Hills Estates
- Velocity Clinical Research -- Banning — San Bernardino
- Artemis Institute for Clinical Research — San Diego
Arizona
- Lenzmeier Family Medicine - Avacare — Glendale
- Desert Clinical Research — Mesa
- Velocity Clinical Research - Phoenix — Phoenix
- Foothills Research Center/Avacare — Phoenix
- Headlands Research Scottsdale — Scottsdale
- Fiel Family and Sports Medicine / Avacare — Tempe
Alabama
- Accel Clinical Research — Birmingham
- Cullman Clinical Trials — Cullman
- AMR Clinical Mobile — Mobile
- Velocity Clinical Research, Mobile — Mobile
Colorado
- Tekton Research, LLC — Denver
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 30,000 participants |
| Start Date | 2025-11-26 |
| Est. Completion | 2027-06-16 |
| Phase | Phase 4 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT07266558
The ClinicalTrials.gov registry entry for NCT07266558 describes a study currently listed as recruiting. It is categorized as Phase 4, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 30,000 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is ModernaTX, which has 67 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 1 condition, with SARS-CoV-2 appearing as the primary indexed condition, and to 3 interventions — of which Placebo is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT07266558 reports 20 study locations spanning 4 distinct geographic areas — top geographies include California, Arizona, Alabama. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT07266558 about?
NCT07266558 is a clinical study titled "A Study to Evaluate the Efficacy and Safety of mRNA-1283 and mRNA-1273 in Participants 50 to 64 Years of Age Without High-Risk Conditions for Severe Coronavirus Disease 2019 (COVID-19)". The purpose of this study is to evaluate the efficacy and safety of mRNA-1283 and mRNA-1273 (variant formulations) in adults 50 to 64 years of age without high risk factors for severe COVID-19.
What is the current status of trial NCT07266558?
This trial is currently recruiting. It is a Phase 4 study. The enrollment target is 30,000 participants. The study started on 2025-11-26. Estimated completion is 2027-06-16.
What conditions does trial NCT07266558 study?
This clinical trial studies the following conditions: SARS-CoV-2. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT07266558?
The interventions under investigation include: Placebo (BIOLOGICAL), mRNA-1273 (BIOLOGICAL), mRNA-1283 (BIOLOGICAL). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT07266558?
This trial is sponsored by ModernaTX, which has 67 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT07266558 being conducted?
This trial has 20 study locations across Alabama, Arizona, California, Colorado. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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