A Study to Evaluate Safety and Effectiveness of mRNA-1273 Vaccine in Healthy Children Between 6 Months of Age and Less Than 12 Years of Age

Study Purpose

The primary goal for this study is to evaluate up to 3 dose levels of mRNA-1273 vaccine given to healthy children in 2 doses, 28 days apart.

Recruitment Criteria

Accepts Healthy Volunteers

Healthy volunteers are participants who do not have a disease or condition, or related conditions or symptoms

Study Type

An interventional clinical study is where participants are assigned to receive one or more interventions (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes.

An observational clinical study is where participants identified as belonging to study groups are assessed for biomedical or health outcomes.

Searching Both is inclusive of interventional and observational studies.

Eligible Ages 6 Months - 11 Years
Gender All
More Inclusion & Exclusion Criteria


Inclusion Criteria:

  • - For participants with chronic diseases (such as, asthma, diabetes mellitus, cystic fibrosis, human immunodeficiency virus [HIV] infection), the disease should be stable, per investigator assessment.
  • - Investigator assessment that the parent(s)/legally acceptable representatives understand and are willing and physically able to comply with protocol mandated follow up, including all procedures, written informed consent is provided, and participants provide assent.
  • - Body mass index at or above the third percentile according to World Health Organization (WHO) Child Growth Standards at the Screening Visit.
  • - For female participants of childbearing potential: negative pregnancy test, adequate contraception or has abstained from all activities that could result in pregnancy for at least 28 days prior to the first injection, agreement to continue adequate contraception or abstinence through 3 months following the second injection, and not currently breastfeeding.
  • - For children 6 months to <2 years of age: born at full-term with a minimum birth weight of 2.5 kilograms (kg).

Exclusion Criteria:

  • - Known history of SARS-CoV-2 infection within 2 weeks prior to administration of vaccine or known close contact with anyone with laboratory-confirmed SARS-CoV-2 infection or COVID-19 within 2 weeks prior to administration of vaccine.
  • - Prior administration of an investigational or approved CoV (such as, SARS-CoV-2, SARS CoV, Middle East Respiratory Syndrome CoV) vaccine.
  • - Treatment with investigational or approved agents for prophylaxis against COVID 19 (such as, receipt of SARS-CoV-2 monoclonal antibodies) within 6 months prior to enrollment.
  • - Known hypersensitivity to a component of the vaccine or its excipients.
  • - A medical or psychiatric condition that, according to the investigator's judgment, may pose additional risk as a result of participation, interfere with safety assessments, or interfere with interpretation of results.
  • - History of a diagnosis or condition that, in the judgment of the investigator, may affect study endpoint assessment or compromise participant safety.
  • - Received any non-study vaccine within 14 days before or after any dose of vaccine (except for seasonal influenza vaccine, which is not permitted within 14 days before or after any dose of vaccine) - Received intravenous blood products (red blood cells, platelets, immunoglobulins) within 3 months prior to Day 1.
  • - Participated in an interventional clinical study within 28 days prior to Day 0 or plans to donate blood products while participating in this study.

Trial Details

Trial ID:

This trial id was obtained from ClinicalTrials.gov, a service of the U.S. National Institutes of Health, providing information on publicly and privately supported clinical studies of human participants with locations in all 50 States and in 196 countries.


Phase 1: Studies that emphasize safety and how the drug is metabolized and excreted in humans.

Phase 2: Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition) and additional safety data.

Phase 3: Studies that gather more information about safety and effectiveness by studying different populations and different dosages and by using the drug in combination with other drugs.

Phase 4: Studies occurring after FDA has approved a drug for marketing, efficacy, or optimal use.

Phase 2/Phase 3
Lead Sponsor

The sponsor is the organization or person who oversees the clinical study and is responsible for analyzing the study data.

ModernaTX, Inc.
Principal Investigator

The person who is responsible for the scientific and technical direction of the entire clinical study.

Principal Investigator Affiliation N/A
Agency Class

Category of organization(s) involved as sponsor (and collaborator) supporting the trial.

Overall Status Recruiting
Countries United States

The disease, disorder, syndrome, illness, or injury that is being studied.

Study Website: View Trial Website
Additional Details

This is a Phase 2/3, 2-part, open-label, dose-escalation, age de-escalation, randomized, observer-blind, placebo-controlled, expansion study intended to infer the effectiveness of mRNA-1273 in children aged 6 months to less than 12 years. Please access http://www.kidcovestudy.com for additional information, such as Study Overview, Participation, Site Locations along with contact numbers for each location for the study.

Arms & Interventions


Experimental: mRNA-1273

Part 1: Participants will receive 2 intramuscular (IM) injections of mRNA-1273 at up to 3 doses pre-specified for this study, 28 days apart, on Day 1 and Day 29. Part 2: Participants will receive 2 IM injections of of mRNA-1273 at the dose selected from Part 1, 28 days apart, on Day 1 and Day 29.

Placebo Comparator: Placebo

Part 2 only: Participants will receive 2 IM injections of mRNA-1273-matching placebo 28 days apart, on Day 1 and Day 29.


Biological: - mRNA-1273

Sterile liquid for injection

Biological: - Placebo

0.9% sodium chloride (normal saline) injection

Contact a Trial Team

If you are interested in learning more about this trial, find the trial site nearest to your location. We also strongly recommend that you consult with your healthcare provider about the trials that may interest you. Please note all sites listed may not currently be active in the trial. Please continue to check back for additional site locations.

MedPharmics, LLC
Recruiting | Phoenix, Arizona, United States, 85015-1105
See if you Qualify
Emmaus Research Center Inc
Recruiting | Anaheim, California, United States, 92804-1866
See if you Qualify
Carey Chronis MD Pediatric, Infant and Adolescent Medicine - FOMAT
Recruiting | Ventura, California, United States, 93003-5369
See if you Qualify
Michael W Simon, MD PSC
Recruiting | Lexington, Kentucky, United States, 40517-8379
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MedPharmics - Platinum
Recruiting | Metairie, Louisiana, United States, 70006-4152
See if you Qualify
Coastal Pediatric Associates
Recruiting | Charleston, South Carolina, United States, 29414-5834
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Javara Inc.
Recruiting | Dallas, Texas, United States, 75230-2571
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BRCR Global Texas
Recruiting | Edinburg, Texas, United States, 78539-8462
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West Houston Clinical Research - Hunt
Recruiting | Houston, Texas, United States, 77055-1626
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Village Health Partners - HUNT
Recruiting | Plano, Texas, United States, 75024
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Crossroads Clinical Research (Victoria)
Recruiting | Port Lavaca, Texas, United States, 77979
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DM Clinical Research - Pediatric Healthcare of NW Houston
Recruiting | Tomball, Texas, United States, 77375-6579
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Advanced Clinical Research/Velocity Clinical Research
Recruiting | Jordan, Utah, United States, 84088
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Tanner Clinic
Recruiting | Layton, Utah, United States, 84041
See if you Qualify