A Study to Investigate the Safety and Immunogenicity of the Quadrivalent Influenza mRNA Vaccines in Adults Aged 18 Years and Above
Public ClinicalTrials.gov record NCT06361875. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.
Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.
Official title
A Phase I/II Study to Investigate the Safety and Immunogenicity of Quadrivalent Influenza mRNA Vaccines MRT5421, MRT5424, and MRT5429 in Healthy Participants Aged 18 Years and Above
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
The purpose of this study was to evaluate the safety and immunogenicity of a single intramuscular (IM) injection of different formulations of Quadrivalent Influenza Vaccine (QIV) messenger ribonucleic acid (mRNA) (MRT5421, MRT5424, and MRT5429) compared to an active control (QIV- standard dose (SD), QIV- high dose (HD) \[adults ≥ 65 years of age only\], or quadrivalent recombinant influenza vaccine (RIV4)) in adults 18 years of age and older.
Study identification
- NCT ID
- NCT06361875
- Recruitment status
- Completed
- Study type
- Interventional
- Phase
- Phase 1, Phase 2
- Enrollment
- 908 participants
Conditions and interventions
Conditions
Interventions
- Quadrivalent Influenza mRNA Vaccine MRT5421 Biological
- Quadrivalent Influenza mRNA Vaccine MRT5424 Biological
- Quadrivalent Influenza mRNA Vaccine MRT5429 Biological
- Quadrivalent Influenza Standard Dose Vaccine Biological
- Quadrivalent Influenza High-Dose Vaccine Biological
- Quadrivalent Recombinant Influenza Vaccine Biological
Biological
Eligibility (public fields only)
- Age range
- 18 Years and older
- Sex
- All
- Healthy volunteers
- Accepts healthy volunteers
This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.
Study timeline
- Start date
- Apr 1, 2024 (Actual)
- Primary completion
- Jun 9, 2025 (Actual)
- Completion
- Jun 9, 2025 (Actual)
- Last update posted
- Aug 4, 2026
2024 – 2025
United States locations
- U.S. sites
- 11
- U.S. states
- 10
- U.S. cities
- 11
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| California Research Foundation Site Number : 8400038 | San Diego | California | 92123-1881 | — |
| Indago Research and Health Center- Site Number : 8400032 | Hialeah | Florida | 33012 | — |
| Cenexel Research Centers of America- Site Number : 8400037 | Hollywood | Florida | 33024 | — |
| Brengle Family Medicine Site Number : 8400045 | Indianapolis | Indiana | 46260 | — |
| AMR Lexington- Site Number : 8400042 | Lexington | Kentucky | 40509 | — |
| Velocity Clinical Research- New Orleans Site Number : 8400053 | New Orleans | Louisiana | 70119 | — |
| The Alliance for Multispecialty Research - KCM, LLC- Site Number : 8400034 | Kansas City | Missouri | 64114 | — |
| Velocity Clinical Research Norfolk- Site Number : 8400046 | Norfolk | Nebraska | 68701 | — |
| AMR Knoxville- Site Number : 8400043 | Knoxville | Tennessee | 37909 | — |
| Clinical Trials of Texas, Inc. - PPDS- Site Number : 8400029 | San Antonio | Texas | 78229 | — |
| Cenexel JBR- Site Number : 8400051 | Salt Lake City | Utah | 84107 | — |
Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.
Non-U.S. locations
This page focuses on the U.S. directory. The official record also lists 2 non-U.S. sites.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT06361875, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
- What this page does not do
- No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
- Where the data comes from
- Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
- Last refresh
- Last update posted Aug 4, 2026 · Synced Oct 17, 2026
Related: full search, browse by condition, browse by drug or therapy, browse by sponsor, browse by U.S. city.
Open the official record
The complete public registry record, listed eligibility criteria, and available contact information for NCT06361875 live on ClinicalTrials.gov.