Actively Recruiting
A Phase 3b/4, Open-label Study to Evaluate the Immunogenicity and Safety of mRNA-1283 COVID-19 Variant-containing Vaccine Formulations
Led by ModernaTX, Inc. · Updated on 2026-05-19
832
Participants Needed
5
Research Sites
N/A
Total Duration
On this page
AI-Summary
What this Trial Is About
Researchers are evaluating the immune response and safety of the mRNA-1283 COVID-19 vaccine containing updated variant formulations in the current health environment. The study uses a flexible master protocol to assess different variant vaccines, with each new vaccine evaluated under a specific subprotocol. Subprotocol 01 focuses on people aged 65 and older, and those aged 12 to under 65 with at least one condition increasing their risk of severe COVID-19 outcomes. Participants receive an intramuscular injection of the mRNA-1283.251 variant-containing formulation. The study has two parts: Part A was stopped to add Part B, which collects detailed safety data and follows participants longer after vaccination. The trial is open-label, meaning all participants receive the vaccine without a comparison group or placebo. During the study, participants will have blood tests to measure neutralizing antibodies against COVID-19 variants before vaccination and 29 days after. Researchers will also monitor for side effects in the first week and up to 181 days after vaccination. The study will assess immune response, safety, and adverse events, with participation lasting several months to ensure thorough follow-up.
CONDITIONS
Brief Title
A Study to Evaluate the Immunogenicity and Safety of mRNA-1283 COVID-19 Variant-containing Formulations
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Age 65 years or older at the time of informed consent, or age 12 to under 65 years with at least one risk factor for severe COVID-19 outcomes
- Willing and physically able to comply with all study procedures and follow-up
- For participants assigned female at birth or who could become pregnant: i) Negative pregnancy test at screening and before vaccination ii) Use of adequate contraception or abstinence for at least 28 days before first dose iii) Agreement to continue contraception for 28 days after vaccination
You will not qualify if you...
- COVID-19 infection within 6 months prior to enrollment
- Acute illness or fever (temperature 38.0°C/100.4°F or higher) within 72 hours before screening or Day 1
- Clinically unstable conditions affecting safety or study assessments
- Receipt of COVID-19 vaccine within 6 months prior to enrollment
- Receipt or planned receipt of any licensed non-COVID-19 vaccine within 28 days before or after study intervention, except influenza vaccine within 14 days before or after
- Use of systemic immunosuppressants for more than 14 days in total within 180 days prior to screening, or planned immunosuppressive treatment during study
- Use of systemic immunoglobulins, long-acting biologics affecting immunity, or blood products within 90 days prior to screening, or planned during study
- History of severe allergic reaction to any mRNA vaccine or its components
- Blood donation of 450 mL or more within 28 days prior to screening, or planned donation within 28 days after vaccination
- Other protocol-specified criteria may apply
AI-Screening
AI-Powered Screening
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Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
1 visit (in-person)
Duration - Single day
Participants receive an intramuscular injection of the mRNA-1283.251 variant-containing COVID-19 vaccine formulation.
1 vaccination visit
Duration - Up to 6 months (181 days)
Participants are monitored for safety and immune response after vaccination, including assessment of adverse events and antibody levels.
Multiple visits up to Day 181 for safety and immunogenicity assessments
Trial Site Locations
Total: 5 locations
1
DelRicht Research-Atlanta
Atlanta, Georgia, United States, 30329
Actively Recruiting
2
DelRicht Research-Baton Rouge
Baton Rouge, Louisiana, United States, 70769
Actively Recruiting
3
DelRicht Research-New Orleans
New Orleans, Louisiana, United States, 70115
Actively Recruiting
4
DelRicht Research-Gulfport
Gulfport, Mississippi, United States, 39503
Actively Recruiting
5
DelRicht Research-Tulsa
Tulsa, Oklahoma, United States, 74133
Actively Recruiting
Research Team
M
Moderna WeCare Team
How is the study designed?
Study Type
INTERVENTIONAL
Masking
NONE
Allocation
NA
Model
SINGLE_GROUP
Primary Purpose
PREVENTION
Number of Arms
1
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