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A Clinical Study Investigating the Safety and Immune Responses After Immunization With Investigational Monkeypox Vaccines
NCT05988203 · View on ClinicalTrials.gov ↗
Study Summary
This is a dose-escalation, Phase I/II study evaluating the safety, tolerability, reactogenicity and immunogenicity of the investigational RNA-based multivalent vaccine candidate BNT166a for active immunization against monkeypox (mpox). This study started with substudy A (SSA) and substudy B (SSB) for which recruitment has been completed. A Substudy C (SSC) was planned, but the sponsor decided not to conduct it. This study will therefore continue with substudy D (SSD). In SSA and SSB, dosing started with an initial sentinel group, followed by the expansion cohort. This study was initially planned to investigate two vaccine candidates (the quadrivalent BNT166a and the trivalent BNT166c). The sponsor decided to not activate the groups with BNT166c.
Conditions Studied
Interventions
- BIOLOGICAL BNT166a
Study Locations (8)
Other
- Addenbrooke's Hospital - Cambridge University Hospitals NHS Foundation Trust — Cambridge
- Royal Surrey County Hospital Foundation Trust, NIHR Royal Surrey Clinical Research Facility — Guildford
- Guy's and St Thomas' NHS Foundation Trust of St Thomas' Hospital — London
- University Hospital Southampton — Southampton
California
- California Research Foundation — San Diego
Missouri
- Alliance for Multispecialty Research, LLC — Kansas City
Tennessee
- Alliance for Multispecialty Research, LLC — Knoxville
Washington
- University of Washington Virology Research Clinic — Seattle
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 96 participants |
| Start Date | 2023-09-21 |
| Est. Completion | 2026-03 |
| Phase | Phase 1 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT05988203
The ClinicalTrials.gov registry entry for NCT05988203 describes a study currently listed as active not recruiting. It is categorized as Phase 1, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 96 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is BioNTech SE, which has 123 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 1 condition, with Monkeypox appearing as the primary indexed condition, and to 1 intervention — of which BNT166a is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT05988203 reports 8 study locations spanning 5 distinct geographic areas — top geographies include Other, California, Missouri. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT05988203 about?
NCT05988203 is a clinical study titled "A Clinical Study Investigating the Safety and Immune Responses After Immunization With Investigational Monkeypox Vaccines". This is a dose-escalation, Phase I/II study evaluating the safety, tolerability, reactogenicity and immunogenicity of the investigational RNA-based multivalent vaccine candidate BNT166a for active immunization against monkeypox (mpox). This study started with substudy A (SSA) and substudy B (SSB) f...
What is the current status of trial NCT05988203?
This trial is currently active not recruiting. It is a Phase 1 study. The enrollment target is 96 participants. The study started on 2023-09-21. Estimated completion is 2026-03.
What conditions does trial NCT05988203 study?
This clinical trial studies the following conditions: Monkeypox. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT05988203?
The interventions under investigation include: BNT166a (BIOLOGICAL). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT05988203?
This trial is sponsored by BioNTech SE, which has 123 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT05988203 being conducted?
This trial has 8 study locations across California, Missouri, Tennessee, Washington. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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