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NCT07500506 · ClinicalTrials.gov registry record · Phase 3
A Study to Learn About the Safety, Tolerability, and Immunogenicity of a Fifth Dose of 6-Valent OspA-Based Lyme Disease Vaccine
A Phase 3 study, sponsored by Pfizer.
- Recruiting
- Registry status
- Phase 3
- Development phase
- 1,712
- Enrollment target
NCT07500506: Recruiting Phase 3 study, sponsored by Pfizer.
NCT07500506 is a Phase 3 study that is actively recruiting participants, run by Pfizer. The registered enrollment target is 1,712 participants, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (122% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT07500506, a Phase 3 study, is actively recruiting participants, sponsored by Pfizer.
- RECRUITING
- Registry status
- Phase 3
- Development phase
- 1,712 participants
- Enrollment target
Study Summary
The purpose of this study is to learn about the safety effects of the Lyme disease vaccine (called VLA15), and its ability to protect people from Lyme disease after a 5th dose of the vaccine. This study is seeking participants who: * are generally healthy and 7 years of age and older, * have already been vaccinated with 4 doses of VLA15 (from the VALOR study), and have blood sample taken post dose 4. * are not currently taking, or haven't recently taken, medicines like chemotherapy, blood products, or blood thinners. * are not pregnant or breastfeeding and do not plan to become pregnant while receiving the study vaccine. All participants in this study will receive a total of 1 dose through a shot in the upper arm, either VLA15 or saline shot (saltwater). The study will compare the experiences of people receiving the study vaccine or saltwater shot. Participants will take part in this study for about 12 months. During this time, they will have 4 planned clinic visits. The clinic visits may include having a health check, giving a small amount of blood and getting the study vaccine or saltwater as a shot at the first visit.
Interventions
- BIOLOGICAL Placebo
- BIOLOGICAL VLA15
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 1,712 participants |
| Start Date | 2026-04-08 |
| Est. Completion | 2026-12-04 |
| Phase | Phase 3 |
What NCT07500506 shows while recruiting
NCT07500506 is an interventional study that assigns participants to a tested intervention. Its 1,712 participants enrollment target places it among the larger protocols in the corpus, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (122% higher).
The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.
NCT07500506 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT07500506 about?
NCT07500506 is a clinical study titled "A Study to Learn About the Safety, Tolerability, and Immunogenicity of a Fifth Dose of 6-Valent OspA-Based Lyme Disease Vaccine". The purpose of this study is to learn about the safety effects of the Lyme disease vaccine (called VLA15), and its ability to protect people from Lyme disease after a 5th dose of the vaccine. This study is seeking participants who: * are generally healthy and 7 years of age and older, * have alrea...
What is the current status of trial NCT07500506?
This trial is currently recruiting. It is a Phase 3 study. The enrollment target is 1,712 participants. The study started on 2026-04-08. Estimated completion is 2026-12-04.
What interventions are being tested in trial NCT07500506?
The interventions under investigation include: Placebo (BIOLOGICAL), VLA15 (BIOLOGICAL).
Who is sponsoring clinical trial NCT07500506?
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 NCT07500506's enrollment target sits among peer trials
1,712 132nd of 2000 higher than 1,869 of 2,000 other Phase 3 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 3 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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