SARS-CoV-2Phase 4NCT06585241
A Study to Investigate the Immunogenicity and Safety of mRNA COVID-19 Variant-containing Vaccine Formulations
A Phase 4 study testing mRNA-1273 Variant-containing Formulation in people with SARS-CoV-2, run by ModernaTX, Inc. at 6 sites in United States.
Trial summary
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). Read more about this study
- Who is it for?
- Ages 6 months and olderHealthy volunteers can take part
- Conditions the study is for
- SARS-CoV-2
- What is being tested?
- mRNA-1273 Variant-containing Formulation
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 1,144 participants
- Where
- 6 sitesUnited States
- Study dates
- 9 Sep 2024to 31 Dec 2026
- Phase
- Phase 4
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 6 months and older
- All sexes
- Healthy volunteers accepted
- Child, Adult, Older adult
Who may be able to join
- 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.
Who cannot join
- 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.
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- 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.
Trial locations and contacts
6 sites in 1 country. Contact the study team or a site near you to ask about taking part.
6 sites in 1 country
United States6 sites, 6 recruiting
- Recruiting
CenExel
Atlanta, Georgia, 30331
- Recruiting
Velocity Clinical Research
Baton Rouge, Louisiana, 70809
- Recruiting
CenExel
Decatur, Georgia, 30030
- Recruiting
Velocity Clinical Research
Gulfport, Mississippi, 39503
- Recruiting
Velocity Clinical Research
Omaha, Nebraska, 68134
- Recruiting
Richard Bennett - Clinical Research Partners
Richmond, Virginia, 23226
About this study
Official title: A Phase 3b/4, Open-label Study to Assess the Immunogenicity and Safety of mRNA COVID-19 Variant-containing Vaccine Formulations
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).
Read the detailed description
This study uses a master protocol with a generic study design to allow flexibility in evaluating immunogenicity of variant-containing formulations of the mRNA-1273 COVID-19 vaccine. As different variant-containing vaccine formulations will be evaluated, each study intervention will be described in the subprotocol. For each evaluation of an updated variant vaccine or age group, a new subprotocol will be generated. Reported outcome measures are based upon master protocol. Not all reported outcome measures may be applicable to each subprotocol.
- Conditions
- SARS-CoV-2
- Being tested
- mRNA-1273 Variant-containing Formulation
- Keywords
- mRNA-1273, mRNA-1273 vaccine, SARS-CoV-2, SARS-CoV-2 Vaccine, Coronavirus, Virus Diseases, Messenger RNA, COVID-19, COVID-19 Vaccine, Variant, Moderna, Pediatric
- Medical subject headings
- Coronavirus Infections, Virus Diseases, COVID-19
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
mRNA-1273 Variant-containing FormulationBiological
Sterile liquid for injection
| Study group | Role | What they receive |
|---|---|---|
| mRNA-1273 Variant-containing Formulation | Experimental | Participants will receive intramuscular (IM) injection(s) of an mRNA-1273 variant-containing formulation (mRNA-1273.167, mRNA-1273.712, mRNA-1273.251, or mRNA-1273.261). Receives: Biological: mRNA-1273 Variant-containing Formulation |
What is being measured
The primary outcome is the main question the study is designed to answer.
mRNA-1273.167, mRNA-1273.712, mRNA-1273.251, and mRNA-1273.261: Geometric Mean Value of Neutralizing Antibody Against COVID-19 Variants
Measured: Up to Day 29
mRNA-1273.167, mRNA-1273.712, mRNA-1273.251, and mRNA-1273.261: Geometric Mean Fold Rise of Neutralizing Antibody Against COVID-19 Variants
Measured: Up to 28 days after last dose of study intervention
mRNA-1273.251 and mRNA-1273.261: Seroresponse Rate
Measured: Up to Day 29
Secondary outcomes (4)
mRNA-1273.251: Geometric Mean Titer of Neutralizing Antibody Against COVID-19 Variants of Participants ≥12 to <65 Years Old and ≥65 Years Old
Measured: Day 29
mRNA-1273.167, mRNA-1273.712, mRNA-1273.251, and mRNA-1273.261: Number of Participants with Serious Adverse Events (SAEs), Adverse Events (AEs) Leading to Study Withdrawal, and AEs of Special Interest
Measured: Day 1 through end of study (up to Day 209)
mRNA-1273.251: Number of Participants with Solicited Local and Systemic Adverse Reactions
Measured: Day 1 through 7 days after last dose of study intervention
mRNA-1273.251 and mRNA-1273.261: Number of Participants with Unsolicited AEs
Measured: Day 1 through 28 days after last dose of study intervention
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Sep 2024
- Study start9 Sep 2024
- Primary completion31 Dec 2026 (estimated)
- Study completion31 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for SARS-CoV-2Studies of the same condition, open and under way.
- More trials run by ModernaTX, Inc.The sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Prevention
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- This is a Phase 3b/4 open-label study.
- Masking
- None (open label)
- Enrolment
- 1,144 participants (estimated)
Sponsor and investigators
- Lead sponsor
- ModernaTX, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06585241
- Sponsor's protocol ID
- mRNA-1273-P403
- Status last verified
- Mar 2026
- First submitted
- 3 Sep 2024
- Last updated
- 27 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 27 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 3b/4, Open-label Study to Assess the Immunogenicity and Safety of mRNA COVID-19 Variant-containing Vaccine Formulations
- ClinicalTrials.gov ID
- NCT06585241
- Acronym / sponsor ID
- mRNA-1273-P403
- Conditions
- SARS-CoV-2
- Keywords
- mRNA-1273, mRNA-1273 vaccine, SARS-CoV-2, SARS-CoV-2 Vaccine, Coronavirus, Virus Diseases, Messenger RNA, COVID-19
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 1,144 participants (estimated)
- Lead sponsor
- ModernaTX, Inc.Industry (pharma, biotech, devices)
- Study start
- 9 Sep 2024 (actual)
- Primary completion
- 31 Dec 2026 (estimated)
- Study completion
- 31 Dec 2026 (estimated)
- First posted
- 5 Sep 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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).
Detailed description
This study uses a master protocol with a generic study design to allow flexibility in evaluating immunogenicity of variant-containing formulations of the mRNA-1273 COVID-19 vaccine. As different variant-containing vaccine formulations will be evaluated, each study intervention will be described in the subprotocol. For each evaluation of an updated variant vaccine or age group, a new subprotocol will be generated. Reported outcome measures are based upon master protocol. Not all reported outcome measures may be applicable to each subprotocol.
Study design
- Primary purpose
- Prevention
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- This is a Phase 3b/4 open-label study.
| Arm | Type | Receives |
|---|---|---|
| mRNA-1273 Variant-containing Formulation | Experimental | Biological: mRNA-1273 Variant-containing FormulationParticipants will receive intramuscular (IM) injection(s) of an mRNA-1273 variant-containing formulation (mRNA-1273.167, mRNA-1273.712, mRNA-1273.251, or mRNA-1273.261). |
Who may qualify
- Ages
- 6 months and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (8 listed)
- 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:
Key exclusion criteria (10 listed)
- 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.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| mRNA-1273 Variant-containing FormulationSterile liquid for injection | Biological | mRNA-1273 Variant-containing Formulation |
Primary outcome
mRNA-1273.167, mRNA-1273.712, mRNA-1273.251, and mRNA-1273.261: Geometric Mean Value of Neutralizing Antibody Against COVID-19 Variants
Time frame: Up to Day 29
mRNA-1273.167, mRNA-1273.712, mRNA-1273.251, and mRNA-1273.261: Geometric Mean Fold Rise of Neutralizing Antibody Against COVID-19 Variants
Time frame: Up to 28 days after last dose of study intervention
mRNA-1273.251 and mRNA-1273.261: Seroresponse Rate
Time frame: Up to Day 29
4 secondary outcomes
mRNA-1273.251: Geometric Mean Titer of Neutralizing Antibody Against COVID-19 Variants of Participants ≥12 to <65 Years Old and ≥65 Years Old
Time frame: Day 29
mRNA-1273.167, mRNA-1273.712, mRNA-1273.251, and mRNA-1273.261: Number of Participants with Serious Adverse Events (SAEs), Adverse Events (AEs) Leading to Study Withdrawal, and AEs of Special Interest
Time frame: Day 1 through end of study (up to Day 209)
mRNA-1273.251: Number of Participants with Solicited Local and Systemic Adverse Reactions
Time frame: Day 1 through 7 days after last dose of study intervention
mRNA-1273.251 and mRNA-1273.261: Number of Participants with Unsolicited AEs
Time frame: Day 1 through 28 days after last dose of study intervention
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 Mar 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
6 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing mRNA-1273 Variant-containing Formulation in people with SARS-CoV-2, run by ModernaTX, Inc. at 6 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 8 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 27 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 6 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Moderna WeCare Team (1-866-663-3762, WeCareClinicalTrials@modernatx.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
mRNA-1273.167, mRNA-1273.712, mRNA-1273.251, and mRNA-1273.261: Geometric Mean Value of Neutralizing Antibody Against COVID-19 Variants (time frame: Up to Day 29). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Mar 2026.