NCT06585241 · ModernaTX, Inc.
A Study to Investigate the Immunogenicity and Safety of mRNA COVID-19 Variant-containing Vaccine Formulations
What this study is about
The purpose of this study is to investigate the immunogenicity and safety of mRNA COVID-19 variant-containing vaccine formulations against the vaccine-matched variants and newly emerged variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
View original scientific description
The purpose of this study is to investigate the immunogenicity and safety of mRNA COVID-19 variant-containing vaccine formulations against the vaccine-matched variants and newly emerged variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- mRNA-1273.167 and mRNA-1273.712: Previously vaccinated adults aged ≥18 years
- mRNA-1273.251: Participants ≥65 years of age, ≥12 to \<65 years of age, or ≥6 months to \<12 years of age with at least 1 risk factor for severe outcomes from COVID-19.
- mRNA-1273.261: ≥65 years of age at the time of signing the informed consent or ≥18 to \<65 years of age at the time of signing the informed consent with at least 1 risk factor for severe outcomes from COVID-19.
- Able to comply with study procedures based on the assessment of the Investigator.
- Female participants of childbearing potential may be enrolled in the study if the participant fulfills all the following criteria:
- Has a negative pregnancy test at the Screening Visit and on the day of vaccination prior to vaccine dose being administered on Day 1.
- Has practiced adequate contraception or has abstained from all activities that could result in pregnancy for at least 28 days prior to the first dose.
- Has agreed to continue adequate contraception through 28 days following vaccine administration. Key
Exclusion criteria
- History of SARS-CoV-2 infection within 3 months prior to enrollment for mRNA-1273.167 and mRNA-1273.712 or within up to 6 months prior to enrollment for mRNA-1273.251 and mRNA-1273.261.
- Is acutely ill or febrile (temperature 38.0°Celsius/100.4°Fahrenheit) less than 72 hours prior to or at the Screening Visit or Day 1. Participants meeting this criterion may be rescheduled within the Screening window.
- History of a diagnosis or condition that, in the judgment of the Investigator, is clinically unstable, or may affect participant safety, assessment of study endpoints, assessment of immune response, or adherence to study procedures.
- History of anaphylaxis or severe hypersensitivity reaction requiring medical intervention after receipt of any mRNA vaccine or therapeutic or any components of an mRNA vaccine or therapeutic.
- Receipt of COVID-19 vaccine within 3 months prior to enrollment for mRNA-1273.167 and mRNA-1273.712 or within 6 months prior to enrollment for mRNA-1273.251 and mRNA-1273.261.
- Receipt of any licensed non-COVID-19 vaccine within 14 days (inactivated vaccine, pediatric) or 28 days before or planned receipt within 14 days (pediatric) or 28 days after the study intervention, except an influenza vaccine, which may be given at least 7 days before (pediatric) or 14 days before or after receipt of the study intervention.
- Receipt of systemic immunosuppressants or immune-modifying drugs for \>14 days total (within 6 months prior to Screening for mRNA-1273.167 and mRNA-1273.712 or within 180 days prior to Screening for mRNA-1273.251 and mRNA-1273.261) or is anticipating the need for immunosuppressive treatment at any time during participation in the study.
- Receipt of systemic immunoglobulins, long-acting biological therapies that affect immune (pediatric) responses, or blood products (within 3 months prior to Screening for mRNA-1273.167 and mRNA-1273.712 or within 90 days prior to the Screening for mRNA-1273.251 and mRNA-1273.261) or plans for receipt during the study.
- Has donated ≥450 milliliters of blood products within 28 days prior to the Screening Visit or plans to donate blood products during the study. Other protocol-defined inclusion/exclusion criteria may apply.
Where
- Atlanta, Georgia
- Decatur, Georgia
- Baton Rouge, Louisiana
- Gulfport, Mississippi
- Omaha, Nebraska
- Richmond, Virginia
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Mar 27, 2026 · Source of record for eligibility and locations