A Study to Evaluate the Safety, Reactogenicity, and Effectiveness of mRNA-1273 Vaccine in Adolescents 12 to <18 Years Old to Prevent COVID-19

NCT ID: NCT04649151

Last Updated: 2025-09-15

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE2/PHASE3
• Total Enrollment: 4328 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2020-12-09
• Study Completion Date: 2024-06-14

Brief Summary

The mRNA-1273 vaccine is being developed to prevent COVID-19, the disease resulting from Severe Acute Respiratory Syndrome coronavirus (SARS-CoV-2) infection. The study is designed to primarily evaluate the safety, reactogenicity, and effectiveness of mRNA-1273 vaccine administered as primary series and a booster dose (BD) to an adolescent population. The study will also evaluate the safety and immunogenicity of an mRNA-1273.222 vaccine against the SARS-CoV- 2 omicron variant as a primary series.

Detailed Description

This is a Phase 2/3 study, with Part 1A (Blinded Phase), Part 1B (Open-label Observational Phase), Part 1C (Booster Dose [BD] Phase), which consists of Part 1C-1 and Part 1C-2, Part 2 (Open-Label), and Part 3 (Open-label). Participants in Part 1A are blinded to their treatment assignment, with participants receiving either 2 active mRNA-1273 vaccine doses or placebo. Part 1B of the study is designed to offer participants whose age group becomes Emergency Use Authorization (EUA) eligible to be unblinded so that participants who received placebo in Part 1A can request 2 doses of open-label mRNA-1273 vaccine. Part 1C-1 of the study will offer participants in Part 1A and Part 1B who are at least 5 months from the last dose, the option to request a homologous BD of mRNA-1273. Part 1C-2 is designed to provide a heterologous BD of mRNA-1273 to eligible participants who completed primary COVID-19 vaccination series with a non-Moderna vaccine under EUA and are at least 3 months from the last dose. Part 2 is an open-label design. Participants will receive 2 doses and may receive a booster dose of mRNA-1273 SARS-CoV-2 vaccine. Part 3 is an open-label design. Participants will receive up to 2 doses of mRNA-1273.222 vaccine.

Please access http://TeenCoveStudy.com for additional information, such as Study Overview, Participation, Site Locations along with contact numbers for each location for the study.

Conditions

SARS-CoV-2

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: PREVENTION
• Blinding Strategy: QUADRUPLE

Study Groups

mRNA-1273

Part 1A (Blinded Phase): Participants will receive 2 intramuscular (IM) injections of mRNA-1273 (100 microgram [ug] each), 28 days apart, on Day 1 and Day 29.

Part 1B (Open-Label Phase): Participants who cross over from placebo in Part 1A to Part 1B will receive 2 IM injections of mRNA-1273 (100 ug each), 28 days apart on Open Label Day 1 and Open Label Day 29.

Part 2 (Open-Label): Participants will receive 2 IM injections of mRNA-1273 (50 ug each), 28 days apart, on Day 1 and Day 29 and may receive a booster dose on Day 149.

Group Type: EXPERIMENTAL

mRNA-1273

Intervention Type: BIOLOGICAL

Sterile liquid for injection

Placebo

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

Group Type: PLACEBO_COMPARATOR

Placebo

Intervention Type: BIOLOGICAL

0.9% sodium chloride (normal saline) injection

mRNA-1273 BD

Part 1C-1 (BD Phase): Participants will receive 1 IM injection of mRNA-1273 (50 ug) on BD-Day 1, 5 months after the last dose of Part 1A and 1B.

Part 1C-2 (BD Phase): Participants will receive 1 IM injection of mRNA-1273 (50 ug) on BD-Day 1, at least 3 months post-last dose.

Group Type: EXPERIMENTAL

mRNA-1273

Intervention Type: BIOLOGICAL

Sterile liquid for injection

mRNA-1273.222

Part 3 (Open-Label): Participants will receive up to 2 IM injections of mRNA-1273.222 (50 ug each), 6 months apart, on Day 1 and Day 181.

Group Type: EXPERIMENTAL

mRNA-1273.222

Intervention Type: BIOLOGICAL

Sterile solution for injection

Interventions

mRNA-1273

Sterile liquid for injection

Intervention Type: BIOLOGICAL

Placebo

0.9% sodium chloride (normal saline) injection

Intervention Type: BIOLOGICAL

mRNA-1273.222

Sterile solution for injection

Intervention Type: BIOLOGICAL

Eligibility Criteria

Inclusion Criteria

For Part 1A, Part 2 and Part 3:

• Participants 12 to <18 years of age at the time of consent (Screening Visit, Day 0) who, in the opinion of the Investigator, are in good general health based on review of medical history and screening physical examination.
• Investigator assessment that the participant, in the case of an emancipated minor, or parent(s)/legally acceptable representative(s) (LAR[s]) understand and is willing and physically able to comply with protocol-mandated follow up, including all procedures and provides written informed consent/assent.
• Body mass index (BMI) at or above the third percentile according to World Health Organization (WHO) Child Growth Standards at the Screening Visit (Day 0)
• Female participants of nonchildbearing potential may be enrolled in the study. Nonchildbearing potential is defined as premenarche or surgically sterile (history of bilateral tubal ligation, bilateral oophorectomy, hysterectomy).
• Female participants of childbearing potential may be enrolled in the study if the participant has a negative pregnancy test at Screening (Day 0), on the day of the first injection (Day 1), on the day of the second injection (Day 29 in Parts 1A and Part 2, and Day 181 in Part 3); has practiced adequate contraception or has abstained from all activities that could result in pregnancy for at least 28 days prior to the first injection (Day 1); and has agreed to continue adequate contraception or abstinence through 3 months following the second injection (Day 29 in Part 1A and Part 2, and Day 181 in Part 3).

For Part 1B:

• Participants must have been previously enrolled in mRNA-1273-P203 study.
• Female participants of childbearing potential may be enrolled in the study if the participant has a negative pregnancy test on the day of the first injection (Open-Label-Day 1) and on the day of the second injection (Open-Label-Day 29).

For Part 1C-1 Homologous Booster Dose:

• Participants must have been previously enrolled in the mRNA-1273-P203 study, are actively participating in Part 1A or Part 1B and are least 5 months from the last dose.
• Female participants of childbearing potential may be enrolled in the study if the participant has a negative pregnancy test on the day of the first injection (BD-Day 1).

Part 1C-2 Heterologous Booster Dose:

• Male or female, 12 to < 18 years of age at the time of consent who, in the opinion of the investigator, is in good general health based on review of medical history and screening physical examination AND has completed non-Moderna primary COVID-19 vaccination series under EUA (for example, Pfizer) at least 3 months from consent.

Exclusion Criteria

For Part 1A, Part 2, and Part 3:

• Has a known history of SARS-CoV-2 infection within 2 weeks prior to administration of investigational product (IP) or known close contact with anyone with laboratory-confirmed SARS-CoV-2 infection of COVID-19 within 2 weeks prior to administration of IP (Part 2 participants only). For Part 3 participants, known history of SARS-CoV-2 infection within 90 days prior to administration of IP or known close contact with anyone with laboratory-confirmed SARS-CoV-2 infection or COVID-19 within 90 days prior to administration of IP.
• Travel outside of the United States or home country (Part 2 and Part 3 only) in the 28 days prior to the Screening Visit (Day 0).
• Pregnant or breastfeeding
• Is acutely ill or febrile 24 hours prior to or at the Screening Visit (Day 0). Fever is defined as a body temperature ≥38.0°Celsius (C)/≥100.4°Farenheit (F). Participants who meet this criterion may have visits rescheduled within the relevant study visit windows. Afebrile participants with minor illnesses can be enrolled at the discretion of the Investigator.
• Prior administration of an investigational coronavirus (for example, SARS-CoV-2, SARS-CoV, Middle East Respiratory Syndrome [MERS-CoV]) vaccine
• Current treatment with investigational agents for prophylaxis against COVID-19
• Has a medical, psychiatric, or occupational condition that may pose additional risk as a result of participation, or that could interfere with safety assessments or interpretation of results according to the Investigator's judgment
• Current use of any inhaled substance (for example, tobacco or cannabis smoke, nicotine vapors)
• History of chronic smoking (≥1 cigarette a day) within 1 year of the Screening Visit (Day 0)
• History of illegal substance use or alcohol abuse within the past 2 years. This exclusion does not apply to historical cannabis use that was formerly illegal in the participant's state but is legal at the time of screening.
• History of a diagnosis or condition that, in the judgment of the Investigator, may affect study endpoint assessment or compromise participant safety, specifically:

• Congenital or acquired immunodeficiency, including human immunodeficiency virus (HIV) infection
• Suspected active hepatitis
• Has a bleeding disorder that is considered a contraindication to IM injection or phlebotomy
• Dermatologic conditions that could affect local solicited AR assessments
• History of anaphylaxis, urticaria, or other significant AR requiring medical intervention after receipt of a vaccine
• Diagnosis of malignancy within the previous 10 years (excluding nonmelanoma skin cancer)
• Febrile seizures
• Receipt of:

• Any licensed vaccine within 28 days before the first dose of IP or plans for receipt of any licensed vaccine within 28 days before and/or after each dose of IP.
• Systemic immunosuppressants or immune-modifying drugs for >14 days in total within 6 months prior to the day of enrollment (for corticosteroids, ≥20 mg/day prednisone equivalent). Topical tacrolimus is allowed if not used within 14 days prior to the day of enrollment. Participants may have visits rescheduled for enrollment if they no longer meet this criterion within the Screening Visit window. Inhaled, nasal, and topical steroids are allowed.
• Intravenous blood products (red cells, platelets, immunoglobulins) within 3 months prior to enrollment
• Has donated ≥450 milliliters (mL) of blood products within 28 days prior to the Screening Visit (Day 0) or plans to donate blood products during the study
• Participated in an interventional clinical study within 28 days prior to the Screening Visit (Day 0) or plans to do so while participating in this study
• Is an immediate family member or has a household contact who is an employee of the research center or otherwise involved with the conduct of the study

For Part 1C-1 and Part 1C-2:

• Pregnant or breastfeeding.
• Is acutely ill or febrile 24 hours prior to or at the Screening Visit (Day 0). Fever is defined as a body temperature ≥ 38.0°C/≥ 100.4°F. Participants who meet this criterion may have visits rescheduled within the relevant study visit windows. Afebrile participants with minor illnesses can be enrolled at the discretion of the investigator.
• Has a medical, psychiatric, or occupational condition that may pose additional risk as a result of participation, or that could interfere with safety assessments or interpretation of results according to the investigator's judgment.
• History of a diagnosis or condition (after enrolment in Part 1A) that, in the judgment of the investigator, may affect study endpoint assessment or compromise participant safety:

• Suspected active hepatitis
• Has a bleeding disorder that is considered a contraindication to IM injection or phlebotomy
• Dermatologic conditions that could affect local solicited AR assessments
• History of anaphylaxis, urticaria, or other significant AR requiring medical intervention after receipt of a vaccine
• Diagnosis of malignancy (excluding nonmelanoma skin cancer)
• Receipt of:

• Any authorized or licensed vaccine within 28 days before the first dose of IP or plans for receipt of any licensed vaccine through 28 days following the last dose of IP or any seasonal influenza vaccine within 14 days before the first dose of IP or plans for receipt of any seasonal influenza vaccine 14 days following the last dose of IP.
• Participated in an interventional clinical study, other than mRNA-1273-P203 study, within 28 days prior to the Screening Visit (Day 0 [for Part 1C-1], BD-Day 0 [for Part 1C-2]) or plans to do so while participating in this study.

Part 1C-2 Heterologous Booster Dose:

• Has a known history of SARS-CoV-2 infection within 2 weeks prior to administration of IP or known close contact with anyone with laboratory-confirmed SARS-CoV-2 infection or COVID 19 within 2 weeks prior to administration of IP.

• Minimum Eligible Age: 12 Years
• Maximum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Biomedical Advanced Research and Development Authority

FED

Sponsor Role: collaborator

ModernaTX, Inc.

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Velocity Clinical Research - Banning

Banning, California, United States

Paradigm Clinical Research

La Mesa, California, United States

Altus Research - Hunt - PPDS

Lake Worth, Florida, United States

Accel Research Sites - Nona Pediatric Center - ERN - PPDS

Orlando, Florida, United States

Tekton Research - Georgia - PPDS

Chamblee, Georgia, United States

IACT Health - Roswell - IACT - HyperCore - PPDS

Columbus, Georgia, United States

Meridian Clinical Research - (Macon Georgia) - Platinum - PPDS

Macon, Georgia, United States

Clinical Research Atlanta

Stockbridge, Georgia, United States

Velocity Clinical Research - Boise - PPDS

Meridian, Idaho, United States

Olivo Medical and Wellness Center

Chicago, Illinois, United States

Velocity Clinical Research - Valparaiso

Valparaiso, Indiana, United States

Meridian Clinical Research (Sioux City - Iowa)

Sioux City, Iowa, United States

Alliance for Multispecialty Research -El Dorado

El Dorado, Kansas, United States

Johnson County Clin-Trials

Lenexa, Kansas, United States

Velocity Clinical Research - Metairie - PPDS

Metairie, Louisiana, United States

University of Massachusetts Medical School, Molecu

Worcester, Massachusetts, United States

Clinical Research Institute, Inc - CRN - PPDS

Minneapolis, Minnesota, United States

Velocity Clinical Research - Gulfport - PPDS

Gulfport, Mississippi, United States

Sundance Clinical Research - Platinum - PPDS

St Louis, Missouri, United States

Meridian Clinical Research (Hastings-Nebraska) - Platinum - PPDS

Hastings, Nebraska, United States

Quality Clinical Research - HyperCore - PPDS

Omaha, Nebraska, United States

Meridian Clinical Research (Omaha-Nebraska) - Platinum - PPDS

Omaha, Nebraska, United States

Velocity Clinical Research - Albuquerque - PPDS

Albuquerque, New Mexico, United States

Child Healthcare Associates - East Syracuse

East Syracuse, New York, United States

Meridian Clinical Research (Endwell-New York) - Platinum - PPDS

Endwell, New York, United States

Velocity Clinical Research - Cincinnati - PPDS

Cincinnati, Ohio, United States

Lynn Health Science Institute

Oklahoma City, Oklahoma, United States

Vital Prospects Clinical Research Institute PC - CRN - PPDS

Tulsa, Oklahoma, United States

Cyn3rgy Research - ClinEdge - PPDS

Gresham, Oregon, United States

Velocity Clinical Research - Providence - PPDS

East Greenwich, Rhode Island, United States

Coastal Pediatric Associates

Charleston, South Carolina, United States

Meridian Clinical Research - Charleston, SC

Charleston, South Carolina, United States

Coastal Carolina Research Center

North Charleston, South Carolina, United States

Benchmark Research

Austin, Texas, United States

Coastal Bend Research Center

Corpus Christi, Texas, United States

ACRC Trials

Frisco, Texas, United States

DM Clinical Research - Kool Kids Pediatrics - ERN - PPDS

Houston, Texas, United States

Clinical Trials of Texas, Inc. - PPDS

San Antonio, Texas, United States

Tekton Research

San Antonio, Texas, United States

Tekton Research

San Antonio, Texas, United States

Cope Family Medicine - Ogden Clinic - CCT

Bountiful, Utah, United States

Wee Care Pediatrics - Kaysville

Kaysville, Utah, United States

Cottonwood Pediatrics

Murray, Utah, United States

South Ogden Family Medicine/Ogden Clinic - CCT Research

South Ogden, Utah, United States

Alliance for Multispecialty Research

Syracuse, Utah, United States

Advanced Clinical Research - Jordan Valley - ERN - PPDS

West Jordan, Utah, United States

Meridian Clinical Research (Norfolk, Virginia)

Norfolk, Virginia, United States

Meridian Clinical Research - Family Practice Ports - Portsmouth - Platinum - PPDS

Portsmouth, Virginia, United States

Caimed Dominicana S.A.S

Santo Domingo, Nacional, Dominican Republic

Hospital General Regional Dr. Marcelino Velez Santana

Santo Domingo, Nacional, Dominican Republic

Hospital Materno Infantil San Lorenzo de Los Mina

Santo Domingo, Nacional, Dominican Republic

Instituto Dermatologico y Cirugia de la Piel Dr. H Sede San Cristóbal

Santo Domingo, Nacional, Dominican Republic

Instituto Dominicano de Estudios Virologicos IDEV

Santo Domingo, Nacional, Dominican Republic

Countries

United States; Dominican Republic

References

Figueroa AL, Torres D, Reyes-Acuna C, Matherne P, Yeakey A, Deng W, Xu W, Sigal Y, Chambers G, Olsen M, Girard B, Miller JM, Das R, Priddy F. Safety and immunogenicity of a single-dose omicron-containing COVID-19 vaccination in adolescents: an open-label, single-arm, phase 2/3 trial. Lancet Infect Dis. 2025 Feb;25(2):208-217. doi: 10.1016/S1473-3099(24)00501-2. Epub 2024 Sep 24.

Reference Type: DERIVED

PMID: 39332418 (View on PubMed)

Ali K, Berman G, Zhou H, Deng W, Faughnan V, Coronado-Voges M, Ding B, Dooley J, Girard B, Hillebrand W, Pajon R, Miller JM, Leav B, McPhee R. Evaluation of mRNA-1273 SARS-CoV-2 Vaccine in Adolescents. N Engl J Med. 2021 Dec 9;385(24):2241-2251. doi: 10.1056/NEJMoa2109522. Epub 2021 Aug 11.

Reference Type: DERIVED

PMID: 34379915 (View on PubMed)

Provided Documents

Document Type: Study Protocol

View Document

Document Type: Statistical Analysis Plan

View Document

Document Type: Informed Consent Form

View Document

Related Links

http://TeenCoveStudy.com

Click here to access the website, http://TeenCoveStudy.com, for additional information for the study, such as Study Overview, Participation, Site Locations, along with contact numbers for each location for the study.

Other Identifiers

2023-000382-14

Identifier Type: EUDRACT_NUMBER

Identifier Source: secondary_id

mRNA-1273-P203

Identifier Type: -

Identifier Source: org_study_id