Safety and Effects of an Investigational COVID-19 Vaccine as Booster in Healthy People
Public ClinicalTrials.gov record NCT05541861. 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
An Exploratory Phase I, Randomized, Observer-blind, Active-controlled, Dose-escalation Trial Evaluating the Safety, Tolerability, and Immunogenicity of an Investigational RNA-based SARS-CoV-2 Vaccine in COVID-19 Vaccine Experienced Healthy Adults
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
This was an exploratory Phase I, randomized, observer-blind, active-controlled, dose-escalation trial to evaluate four dose levels (DLs) of BNT162b4 given in combination with BNT162b2 Bivalent (original/Omicron BA.4/BA.5) to select a safe and tolerable dose and to evaluate BNT162b4 + BNT162b2 Bivalent (original/Omicron BA.4/BA.5) when given as Dose 1 and Dose 2 (booster) in Cohorts 1 and 2 and BNT162b4 + BNT162b2 Monovalent (OMI XBB.1.5) when given as Dose 2 (booster) in Cohorts 3a, 3b, 4a, and 4b, and 30 microgram (mcg) BNT162b4 when given alone as Dose 1 and Dose 2 in Cohort 5. The trial used a staggered dosing process schema, i.e., enrollment into the next higher dose level was done sequentially and subject to safety data from the previous dose levels, with sentinel participants in Cohorts 1, 2, 3a, and 4a. Cohort 3b investigating the same dose level as cohort 3a but in participants aged \>55 years was opened after safety data for participants aged 18-55 years in Cohort 3a had been reviewed. Enrollment into Cohorts 4a and 4b was opened after safety data for Cohort 3a and 3b had been reviewed. Cohort 5 participants were not randomized and received two doses of BNT162b4 alone after which a safety review was performed after all participants received Dose 2 in this cohort. BNT162b4 plus BNT162b2 Bivalent (original/Omicron BA.4/BA.5)/Monovalent (OMI XBB.1.5) was co-administered (as a single injection). BNT162b4 alone was administered as a single injection.
Study identification
- NCT ID
- NCT05541861
- Recruitment status
- Completed
- Study type
- Interventional
- Phase
- Phase 1
- Enrollment
- 383 participants
Conditions and interventions
Conditions
Interventions
- BNT162b2 Bivalent (original/Omicron BA.4/BA.5) 30 mcg Biological
- BNT162b4 5 mcg Biological
- BNT162b4 10 mcg Biological
- BNT162b4 15 mcg Biological
- BNT162b4 30 mcg Biological
- BNT162b2 Monovalent (OMI XBB.1.5) 30 mcg 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
- Nov 7, 2022
- Primary completion
- Nov 21, 2024
- Completion
- Nov 21, 2024
- Last update posted
- Jan 12, 2026
2022 – 2024
United States locations
- U.S. sites
- 17
- U.S. states
- 12
- U.S. cities
- 16
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| Alliance for Multispecialty Research, LLC | Tempe | Arizona | 85281 | — |
| Hoag Hospital | Newport Beach | California | 92663 | — |
| California Research Foundation | San Diego | California | 92123 | — |
| Diablo Clinical Research, Inc. | Walnut Creek | California | 94598 | — |
| Clinical Research Consulting, LLC | Milford | Connecticut | 06460 | — |
| Cenexel RCA (Research Centers of America) | Hollywood | Florida | 33024 | — |
| Research Institute of South Florida, Inc. | Miami | Florida | 33173 | — |
| Great Lakes Clinical Trials LLC - Andersonville | Chicago | Illinois | 60640 | — |
| Johnson County Clin-Trials, Inc. (JCCT) | Lenexa | Kansas | 66219 | — |
| University of Kentucky Center for Clinical and Translational Science (outpatient clinic) | Lexington | Kentucky | 40536 | — |
| Alliance for Multispecialty Research, LLC (Kansas) | Kansas City | Missouri | 64114 | — |
| Finger Lakes Clinical Research | Rochester | New York | 14618 | — |
| CTI Clinical Research Center | Cincinnati | Ohio | 45212 | — |
| Alliance for Multispecialty Research, LLC | Knoxville | Tennessee | 37909 | — |
| Clinical Trials of Texas, LLC / Flourish Research | San Antonio | Texas | 78229 | — |
| Endeavor Clinical Trials, LLC | San Antonio | Texas | 78229 | — |
| DM Clinical Research | Tomball | Texas | 77375 | — |
Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT05541861, 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 Jan 12, 2026 · Synced Sep 3, 2026
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Open the official record
The complete protocol, eligibility criteria, and contact information for NCT05541861 live on ClinicalTrials.gov.