A Study of mRNA-1345, an mRNA Vaccine Targeting Respiratory Syncytial Virus, in Children 2 to <18 Years of Age at High Risk of Respiratory Syncytial Virus

NCT06097299 | Completed Phase 2 FDA Drug

• 2 other identifiers: mRNA-1345-P2022024-000502-15
• Study Type: interventional
• Target: 346
• Locations: 2 countries
• Sites: 50

Brief Summary

Part A: The purpose is to evaluate the safety, reactogenicity, and immunogenicity of mRNA-1345 in children aged 2 to \<5 years (Cohort 1) and in children at high risk of respiratory syncytial virus (RSV) disease 5 to \<18 years of age (Cohort 2) to inform the dose level selection for the next phase of development (Phase 3). Part B: The purpose is to provide surveillance for RSV disease for the next RSV season (6 months after re-enrollment) and safety follow-up for Cohort 1 participants that were enrolled and dosed in Part A.

Conditions

Respiratory Syncytial Virus

Keywords

Pediatric; mRNA-1345; RSV vaccine; Viral Diseases; Messenger RNA; Moderna

Outcome Measures

Primary Outcomes (7)

• Part A: Number of Participants with Solicited Local and Systemic Adverse Reactions (ARs)

  Up to 7 days postinjection

• Part A: Number of Participants with Unsolicited Adverse Events (AEs)

  Up to 28 days postinjection

• Part A: Number of Participants With Medically Attended AEs (MAAEs)

  Day 1 through end of study (EOS; Month 6)

• Part A: Number of Participants With Adverse Events of Special Interest (AESIs)

  Day 1 through EOS (Month 6)

• Part A: Number of Participants With Serious Adverse Events (SAEs)

  Day 1 through EOS (Month 6)

• Part A: Number of Participants With AEs Leading to Discontinuation

  Day 1 through EOS (Month 6)

• Part B: Number of participants With Respiratory syncytial virus-Respiratory tract disease (RSV-RTD), Respiratory syncytial virus- Lower Respiratory tract disease (RSV-LRTD), Severe RSV-LRTD, Very Severe RSV-LRTD and RSV Hospitalization

  Day 1 through EOS (Month 6)

Secondary Outcomes (6)

• Part A: Geometric Mean Titer (GMT) of Serum RSV Neutralizing Antibody

  Day 1, Day 29, and Month 6

• Part A: Geometric Mean Concentration (GMC) of Serum RSV Prefusion F Binding Antibody

  Day 1, Day 29, and Month 6

• Part A: Geometric Mean Fold Rise (GMFR) of Postbaseline/Baseline Neutralizing Antibody Titers and Binding Antibody Concentrations

  Baseline to Day 29 and Month 6

• Part A: Number of Participants With Seroresponse in RSV Neutralizing Antibody

  Baseline to Day 29 and Month 6

• Part B: Number of Participants With AESIs

  Day 1 through EOS (Month 6)

Study Arms (2)

Part A and Part B: Cohort 1 (2 to <5 Years of Age)

EXPERIMENTAL

Part A: Participants 2 to \<5 years of age will receive either a single intramuscular (IM) injection of mRNA-1345 or placebo on Day 1. Part B: Participants will have the option to be re-enrolled into a 6-month safety-follow up period.

Biological: mRNA-1345; Biological: Placebo

Part A: Cohort 2 (5 to <18 Years of Age)

EXPERIMENTAL

Participants 5 to \<18 years of age will receive a single IM injection of mRNA-1345 on Day 1.

Biological: mRNA-1345

Interventions

mRNA-1345 BIOLOGICAL

Sterile liquid for injection

Part A and Part B: Cohort 1 (2 to <5 Years of Age); Part A: Cohort 2 (5 to <18 Years of Age)

Placebo BIOLOGICAL

0.9% sodium chloride (normal saline) injection

Part A and Part B: Cohort 1 (2 to <5 Years of Age)

Eligibility Criteria

• Age: 2 Years - 17 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17)

You may qualify if:

• Part A Cohort 1:
• to \<5 years of age at Day 1.
• Healthy, or with stable chronic conditions increasing the risk of RSV disease, per the clinical judgment of the Investigator.
• Cohort 2:
• to \<18 years of age at Day 1.
• Participants with stable chronic conditions increasing the risk of RSV disease.
• Female participants of child-bearing potential may be enrolled in the study, if the participant: 1) has a negative urine pregnancy test at Screening and on the day of injection (Day 1); 2) has practiced adequate contraception or has abstained from all activities that could lead to pregnancy for 28 days prior to Day 1; 3) has agreed to continue adequate contraception through 90 days following injection; and 4) is not currently breastfeeding.
• Part B: Cohort 1 Re-enrollment
• Participants are eligible to be included in the study only if all of the following criteria apply:
• Enrolled and dosed in Part A of Cohort 1; either reached EoS for Part A or were dosed and subsequently discontinued from study for various reasons. This includes participants who were lost to follow-up, if they can be re-engaged.
• Participant's parent(s)/LAR(s) has provided written informed consent for participation in this study.

You may not qualify if:

• Acutely ill or febrile (temperature ≥38.0°Celsius \[100.4°Fahrenheit\]) within 72 hours prior to or at the Screening Visit or Day 1.
• History of a diagnosis or condition that, in the judgment of the Investigator, may affect study assessment or compromise participant safety.
• Has received or plans to receive any licensed or authorized vaccine ≤14 days prior to the study vaccine injection (Day 1) or plans to receive a licensed or authorized vaccine within 14 days after the study vaccine injection.
• Receipt of any prior systemic immunosuppressants. Short courses (\<7 days) of oral corticosteroids are allowed if completed at least 3 months prior to enrollment.
• Receipt of RSV monoclonal antibodies within 6 months prior to enrollment in the study.
• Participated in an interventional clinical study within 28 days (6 months for a study assessing a product unlicensed/unauthorized in this age group in country of residence at time of enrollment) prior to the day of enrollment or plans to do so while enrolled in this study.
• Part B: Cohort 1 Re-enrollment
• \. Participant is currently enrolled in another interventional clinical study.

Sponsors & Collaborators

• ModernaTX, Inc.: lead

Study Sites (50)

Velocity Clinical Research, Phoenix

Phoenix, Arizona, 85006, United States

Location

Headlands Research - Scottsdale

Scottsdale, Arizona, 85260, United States

Location

Velocity Clinical Research - Banning

Banning, California, 92220, United States

Location

ASCADA Research, LLC - Family Medicine

Fullerton, California, 92835, United States

Location

Ark Clinical Research

Long Beach, California, 90815, United States

Location

Peninsula Research Associates (PRA)

Rolling Hills Estates, California, 90274, United States

Location

D&amp;H Doral Research Center, LLC

Doral, Florida, 33122, United States

Location

Kissimmee Clinical Research

Kissimmee, Florida, 34741, United States

Location

Accel Clinical

Largo, Florida, 33777, United States

Location

Med-Care Research

Miami, Florida, 33125, United States

Location

Accel Research Sites - Nona Pediatric Center

Orlando, Florida, 32829, United States

Location

SEC Clinical Research

Pensacola, Florida, 32501, United States

Location

D&H Tamarac Research Center

Tamarac, Florida, 33321, United States

Location

Javara, Inc.

Fayetteville, Georgia, 30214, United States

Location

Velocity Clinical Research-Primary Pediatrics, Macon

Macon, Georgia, 31210, United States

Location

CenExel iResearch, LLC

Savannah, Georgia, 31405, United States

Location

Clinical Research Prime

Idaho Falls, Idaho, 83404, United States

Location

Velocity Clinical Research - Boise

Meridian, Idaho, 83642, United States

Location

Alliance for Multispeciality Research, LLC

El Dorado, Kansas, 67042, United States

Location

Velocity Clinical Research-Kansas City

Overland Park, Kansas, 66210, United States

Location

Velocity Clinical Research - Lafayette

Lafayette, Louisiana, 70508, United States

Location

Velocity Clinical Research Metairie

Metairie, Louisiana, 70006, United States

Location

Great Lakes Research Institute

Southfield, Michigan, 48075, United States

Location

Pediatric &amp; Adolescent Center

Southgate, Michigan, 48195-1896, United States

Location

Clinical Research Institute

Minneapolis, Minnesota, 55402, United States

Location

Velocity Clinical Research, Gulfport

Gulfport, Mississippi, 39503, United States

Location

Velocity Clinical Research- Albuquerque

Albuquerque, New Mexico, 87107, United States

Location

Velocity Clinical Research-Binghamton

Binghamton, New York, 13905, United States

Location

University of Rochester Medical Center (URMC) - Golisano Children's Hospital (GCH)

Rochester, New York, 14620, United States

Location

Senders Pediatrics

South Euclid, Ohio, 44121, United States

Location

The Children's Hospital of Philadelphia - Pediatrics

Philadelphia, Pennsylvania, 19104-4318, United States

Location

DM Clinical Research - Philadelphia

Philadelphia, Pennsylvania, 19107, United States

Location

Velocity Clinical Research - Providence

Providence, Rhode Island, 02886, United States

Location

Coastal Pediatric Research

Charleston, South Carolina, 29414, United States

Location

Tribe Clinical Research

Simpsonville, South Carolina, 29680, United States

Location

Elligo Clinical Research Center

Austin, Texas, 78704, United States

Location

REX Clinical Trials, LLC

Beaumont, Texas, 77701, United States

Location

Javara Inc (Conroe)

Conroe, Texas, 77384, United States

Location

West Houston Clinical Research Service

Houston, Texas, 77055, United States

Location

DM Clinical Research - CyFair

Houston, Texas, 77065, United States

Location

Village Pediatrics

Plano, Texas, 75024, United States

Location

Javara Inc/Texas Health Care, PLLC d/b/a/ Privia Medical Group-North Texas

Stephenville, Texas, 76401, United States

Location

Victoria Clinical Research Group

Victoria, Texas, 77901, United States

Location

Velocity Clinical Research - Salt Lake City

West Jordan, Utah, 84088, United States

Location

PI-Coor Clinical Research, LLC

Annandale, Virginia, 22003, United States

Location

Clinical Research Partners

Richmond, Virginia, 23226, United States

Location

National Clinical Research, Inc.

Richmond, Virginia, 23294, United States

Location

CEVAXIN Chorrera

La Chorrera, 07066, Panama

Location

CEVAXIN Avenida Mexico

Panama City, 07093, Panama

Location

CEVAXIN 24 de Diciembre

Panama City, 07114, Panama

Location

MeSH Terms

Conditions

Virus Diseases

Interventions

mRNA-1345 respiratory syncytial virus vaccine

Condition Hierarchy (Ancestors)

Infections

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 18, 2023
• First Posted: October 24, 2023
• Study Start: October 24, 2023
• Primary Completion: June 27, 2025
• Study Completion: June 27, 2025
• Last Updated: July 10, 2025

Record last verified: 2025-07

Locations

US (47); PA (3)