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NCT05477524 · ClinicalTrials.gov registry record · Phase 3
An Efficacy, Safety, Tolerability, Immunogenicity, and Lot-Consistency Clinical Trial of a 6-Valent OspA-Based Lyme Disease Vaccine (VLA15)
A Phase 3 study of Lyme Disease, sponsored by Pfizer.
- Active
- Registry status
- Phase 3
- Development phase
- 12,547
- Enrollment target
- 20
- Study locations
NCT05477524: Active Phase 3 study of Lyme Disease, sponsored by Pfizer.
NCT05477524 is a Phase 3 study of Lyme Disease that is active but no longer recruiting, run by Pfizer. The registered enrollment target is 12,547 participants, above the 2,480-participant average among 9 other Lyme Disease trials with a reported enrollment target (406% higher). The trial reports 20 study locations across 4 states. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05477524, a Phase 3 study of Lyme Disease, is active but no longer recruiting, sponsored by Pfizer.
- ACTIVE NOT RECRUITING
- Registry status
- Phase 3
- Development phase
- 12,547 participants
- Enrollment target
- 20
- Study locations
Study Summary
The main purpose of this clinical study is to evaluate a 6-valent OspA-based Lyme disease vaccine (VLA15) for prevention of Lyme disease within North America and Europe. Approximately 9,400 healthy participants (this number excludes participants from 8 sites which were terminated for quality issues) 5 years and older will be recruited from areas with high levels of endemic Lyme disease to receive VLA15 or placebo (an inactive substance consisting of saltwater). Each participant will have about a 50% chance of receiving VLA15 and about a 50% chance of receiving placebo. A subset of participants will receive VLA15 from 3 different lots or placebo (1:1:1:3 ratio) to assess lot equivalence. Participants will receive a 3-dose primary vaccination series at about 0, 2, and 5 to 9 months and then receive a booster dose about 12 months after end of primary vaccination series. Vaccination of participants will occur at a time of year such that the primary series is completed before the peak Lyme disease season followed by a booster dose just prior to the beginning of the second Lyme disease season. A subset of participants will be followed for a third Lyme disease season. Comparison will be made between the Lyme disease cases of people receiving the study vaccine to those of the people who are not. This will help us determine if the study vaccine is safe and effective. If enrolled, participants will need to visit the research site at least 7 times during the study, and for a subset of participants up to 9 times. There will also be at least 5 telephone contacts. It is expected that each participant will take part in this study for up to about 2 and a half years. The subset of participants followed for a third Lyme disease season will take part in this study for up to about to 3 and a half years.
Primary Outcome
A confirmed case of Lyme disease, caused by B burgdorferi sensu lato, is defined as a clinically suspected case of Lyme disease that is confirmed by PCR, culture, microbial cell-free B burgdorferi-specific DNA sequencing, or serological antiborrelial antibody assay, and finally assessed and confirmed to be a case by the independent Adjudication Committee
Conditions Studied
Interventions
- OTHER Saline
- BIOLOGICAL VLA15
Study Locations (20)
Massachusetts
- Pediatric Associates of Fall River - Fall River
- Care Access - Lakeville - Lakeville
- Care Access - Melrose - Melrose
- ActivMed Practices and Research - Methuen
- Care Access - Briarpatch and Mobile Site - Nantucket
- Care Access - Nantucket - Nantucket
- Care Access Mobile Site - Nantucket
- South Shore Medical Center - Norwell
Maryland
- Johns Hopkins - Baltimore
- Johns Hopkins Hospital - Baltimore
- Johns Hopkins Rockland Physician Practice and Research Group - Lutherville
- Sumit Bhutani MD LLC - Westminster
- Woodholme Gastroenterology Associates - Westminster
Connecticut
- Care Access - Essex - Essex
- Care Access Mobile Site - New London
- Stamford Health Medical Group - Stamford
- Stamford Hospital - Stamford
Maine
- Northern Light Eastern Maine Medical Center - Bangor
- Care Access - Farmington - Farmington
- Pen Bay Medical Center - Rockport
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 12,547 participants |
| Start Date | 2022-08-04 |
| Est. Completion | 2025-12-26 |
| Phase | Phase 3 |
What the registry record for NCT05477524 still lists
NCT05477524 is an interventional study that assigns participants to a tested intervention. Its 12,547 participants enrollment target places it among the larger protocols in the corpus, above the 2,480-participant average among 9 other Lyme Disease trials with a reported enrollment target (406% higher).
The record links to 1 condition, with Lyme Disease appearing as the primary indexed condition, and to 2 interventions - of which Saline is the first listed.
NCT05477524 names 20 study sites across 4 states, led by Massachusetts, Maryland, Connecticut.
Frequently Asked Questions
What is clinical trial NCT05477524 about?
NCT05477524 is a clinical study titled "An Efficacy, Safety, Tolerability, Immunogenicity, and Lot-Consistency Clinical Trial of a 6-Valent OspA-Based Lyme Disease Vaccine (VLA15)". The main purpose of this clinical study is to evaluate a 6-valent OspA-based Lyme disease vaccine (VLA15) for prevention of Lyme disease within North America and Europe. Approximately 9,400 healthy participants (this number excludes participants from 8 sites which were terminated for quality issues)...
What is the current status of trial NCT05477524?
This trial is currently active not recruiting. It is a Phase 3 study. The enrollment target is 12,547 participants. The study started on 2022-08-04. Estimated completion is 2025-12-26.
What conditions does trial NCT05477524 study?
This clinical trial studies the following conditions: Lyme Disease.
What interventions are being tested in trial NCT05477524?
The interventions under investigation include: Saline (OTHER), VLA15 (BIOLOGICAL).
Who is sponsoring clinical trial NCT05477524?
This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.
Where is trial NCT05477524 being conducted?
This trial has 20 study locations across Connecticut, Maine, Maryland, Massachusetts. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
Learn More About Clinical Trials
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Where NCT05477524's enrollment target sits among peer trials
12,547 2nd of 9 the highest of 9 other Lyme Disease trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Lyme Disease 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.
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