Study of Monovalent and Bivalent Recombinant Protein Vaccines Against COVID-19 in Adults 18 Years of Age and Older
Public ClinicalTrials.gov record NCT04904549. 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.
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Official title
A Parallel-group, Phase III, Multi-stage, Modified Double-blind, Multi-armed Study to Assess the Efficacy, Safety, and Immunogenicity of Two SARS-CoV-2 Adjuvanted Recombinant Protein Vaccines (Monovalent and Bivalent) for Prevention Against COVID-19 in Adults 18 Years of Age and Older as a Primary Series and Open-label Extension to Assess Immunogenicity, Safety, Efficacy of a Monovalent Booster Dose of SARS-CoV2 Adjuvanted Recombinant Protein Vaccine
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
The purpose of this Phase III study is to assess the efficacy, safety, and immunogenicity of two CoV2 preS dTM-AS03 vaccines (monovalent and bivalent) as part of primary series vaccinations in a multi-stage approach, as well as a booster injection of a CoV2 preS dTM-AS03 vaccine, in adults 18 years of age and older. A total of approximately 21 046 participants are planned to be enrolled (5080 per study intervention group in Stage 1 and 5443 per study intervention group in Stage 2). Initial, double-blind, primary series study design is planned for 365 days post-last Initial injection (ie, approximately 386 days total) for each participant. Based on decisions of the Study Oversight Group, Stage 1 and Stage 2 participants will be invited to participate in an unblinded Crossover / Booster study design with duration as follows: * For participants who initially received vaccine: 12 months post-booster (ie, approximately 18 to 24 months) * For participants who initially received placebo: ≥ 4 months post-last dose of the primary series + 12 months post-booster (ie, approximately 28 to 34 months) * For participants who do not consent to continue in the unblinded Crossover / Booster part of the study, all study procedures will be stopped and participants will be discontinued from the study.
Study identification
- NCT ID
- NCT04904549
- Recruitment status
- Terminated
- Study type
- Interventional
- Phase
- Phase 3
- Enrollment
- 23,670 participants
Conditions and interventions
Conditions
Interventions
- SARS-CoV-2 adjuvanted recombinant protein vaccine (monovalent D614) (primary series) Biological
- SARS-CoV-2 adjuvanted recombinant protein vaccine (bivalent D614 + B.1.351) (primary series) Biological
- Placebo Biological
- SARS-CoV-2 adjuvanted recombinant protein vaccine (monovalent B.1.351) (booster dose) >= 4 months after last vaccination Biological
- SARS-CoV-2 adjuvanted recombinant protein vaccine(monovalent D614)(primary series)& SARS-CoV-2 adjuvanted recombinant protein vaccine(monovalent B.1.351)(booster dose)>=4 months after last vaccination 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
- May 26, 2021 (Actual)
- Primary completion
- Aug 31, 2024 (Actual)
- Completion
- Aug 31, 2024 (Actual)
- Last update posted
- Jun 3, 2026
2021 – 2024
United States locations
- U.S. sites
- 23
- U.S. states
- 15
- U.S. cities
- 23
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| AES - DRS - Simon Williamson Clinic, PC - Birmingham- Site Number : 8400004 | Birmingham | Alabama | 35211 | — |
| Optimal Research Alabama- Site Number : 8400019 | Huntsville | Alabama | 35802 | — |
| Peninsula Research Associates, Inc.- Site Number : 8400021 | Rolling Hills Estates | California | 90274 | — |
| Synexus Clinical Research US, Inc. Site Number : 8400013 | Centennial | Colorado | 80112 | — |
| Optimal Research, LLC-Melbourne- Site Number : 8400002 | Melbourne | Florida | 32934 | — |
| Synexus Clinical Research US, Inc. - Orlando- Site Number : 8400020 | Orlando | Florida | 32806 | — |
| AES St. Petersburg- Site Number : 8400017 | Pinellas Park | Florida | 33781 | — |
| Synexus Clinical Research US, Inc. - Atlanta- Site Number : 8400005 | Atlanta | Georgia | 30328 | — |
| Synexus Clinical Research Chicago- Site Number : 8400012 | Chicago | Illinois | 60602 | — |
| Synexus Clinical Research Evansville- Site Number : 8400008 | Evansville | Indiana | 47714 | — |
| Synexus St. Louis- Site Number : 8400006 | St Louis | Missouri | 63141 | — |
| Synexus Clinical Research US, Inc. - Henderson- Site Number : 8400018 | Henderson | Nevada | 89052 | — |
| Rochester Clinical Research, Inc.- Site Number : 8400023 | Rochester | New York | 14609 | — |
| Synexus Akron- Site Number : 8400009 | Akron | Ohio | 44311 | — |
| Synexus Clinical Research US, Inc. - Cincinnati- Site Number : 8400010 | Cincinnati | Ohio | 45236 | — |
| Synexus US Columbus- Site Number : 8400011 | Columbus | Ohio | 43212 | — |
| Synexus Clinical Research Anderson- Site Number : 8400007 | Anderson | South Carolina | 29621 | — |
| Coastal Carolina Research Center - N Charleston- Site Number : 8400022 | North Charleston | South Carolina | 29405 | — |
| American Indian Clinical Trials Research Network Site Number : 8400025 | Rapid City | South Dakota | 57701 | — |
| AES Austin- Site Number : 8400003 | Austin | Texas | 78744 | — |
| Synexus Dallas- Site Number : 8400014 | Dallas | Texas | 75231 | — |
| Synexus Clinical Research US, Inc. - San Antonio- Site Number : 8400015 | San Antonio | Texas | 78229 | — |
| AES Salt Lake City- Site Number : 8400016 | Murray | Utah | 84123 | — |
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 63 non-U.S. sites.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT04904549, 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 Jun 3, 2026 · Synced Nov 9, 2026
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Open the official record
The complete public registry record, listed eligibility criteria, and available contact information for NCT04904549 live on ClinicalTrials.gov.