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NCT05703607 · ClinicalTrials.gov registry record · Phase 1
A Study to Learn About a Modified RNA Vaccine Against Shingles in Healthy Adults
A Phase 1 study, sponsored by Pfizer.
- Terminated
- Registry status
- Phase 1
- Development phase
- 484
- Enrollment target
NCT05703607: Clinical Trial Phase 1 study, sponsored by Pfizer.
NCT05703607 is a Phase 1 study that was terminated before completion, run by Pfizer. The registered enrollment target is 484 participants, above the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (707% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05703607, a Phase 1 study, was terminated before completion, sponsored by Pfizer.
- TERMINATED
- Registry status
- Phase 1
- Development phase
- 484 participants
- Enrollment target
Study Summary
The purpose of this clinical study is to learn about the safety, extent of the side effects (reaction to vaccine), and immune response (your immune system's reaction) of the study vaccine called Varicella Zoster Virus modRNA (VZV modRNA). We are seeking for healthy participants 50 through 85 years of age. This study will be conducted in 2 substudies: Substudy A (Phase 1) and Substudy B (Phase 2). Substudy A: This substudy is the Phase 1 portion of the study. In this substudy, participants will receive 1 of 3 VZV modRNA vaccine candidates (different construct, different dose levels and different formulation \[frozen or freeze dry powder\]) or the approved shingles vaccine intramuscularly. Participants will be assigned in 1 of 10 groups in the study. Vaccination will be given either as a 2-dose series using one of two dosing schedules (either 2-months apart or 6-months apart), or (in one of the groups), as a single VZV modRNA vaccine at the first vaccination visit and saline at the second vaccination visit. Participants will take part in this study for 8 to 12 months depending on the group they are assigned to. Some group(s) will continue into persistence-of-immunity (overtime assessment of effect of vaccine) portion of the study. Those participants assigned to these selected groups will be involved in the study for up to 5 years. Substudy B: This substudy is the Phase 2 portion of the study. In this part of the study, participants will receive either VZV modRNA vaccine at selected dose level/schedule/formulation or approved shingles vaccine. This selection was determined from data collected in Substudy A. Participants will be involved in this study for up to 5 years.
Primary Outcome
Pain at the injection site, redness, and swelling as self-reported in electronic diaries.
Interventions
- BIOLOGICAL Shingrix
- BIOLOGICAL Candidate 1: PF-07915234: VZV modRNA Powder for Suspension for Injection
- BIOLOGICAL Candidate 1: PF-07915234: VZV modRNA Suspension for Injection
- BIOLOGICAL Candidate 2: PF-07921188: VZV modRNA Suspension for Injection
- BIOLOGICAL Candidate 3: PF-07921186: VZV modRNA Suspension for Injection
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 484 participants |
| Start Date | 2023-01-25 |
| Est. Completion | 2025-09-23 |
| Phase | Phase 1 |
Why NCT05703607 stopped before completion
NCT05703607 is an interventional study that assigns participants to a tested intervention. The registered 484 participants enrollment target is mid-sized for trials with a published cap, above the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (707% higher).
The record links to 0 conditions, and to 5 interventions - of which Shingrix is the first listed.
NCT05703607 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT05703607 about?
NCT05703607 is a clinical study titled "A Study to Learn About a Modified RNA Vaccine Against Shingles in Healthy Adults". The purpose of this clinical study is to learn about the safety, extent of the side effects (reaction to vaccine), and immune response (your immune system's reaction) of the study vaccine called Varicella Zoster Virus modRNA (VZV modRNA). We are seeking for healthy participants 50 through 85 years o...
What is the current status of trial NCT05703607?
This trial is currently terminated. It is a Phase 1 study. The enrollment target is 484 participants. The study started on 2023-01-25. Estimated completion is 2025-09-23.
What interventions are being tested in trial NCT05703607?
The interventions under investigation include: Shingrix (BIOLOGICAL), Candidate 1: PF-07915234: VZV modRNA Powder for Suspension for Injection (BIOLOGICAL), Candidate 1: PF-07915234: VZV modRNA Suspension for Injection (BIOLOGICAL), Candidate 2: PF-07921188: VZV modRNA Suspension for Injection (BIOLOGICAL), Candidate 3: PF-07921186: VZV modRNA Suspension for Injection (BIOLOGICAL).
Who is sponsoring clinical trial NCT05703607?
This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT05703607's enrollment target sits among peer trials
484 48th of 2000 higher than 1,953 of 2,000 other Phase 1 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 1 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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