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An Efficacy, Safety, Tolerability, Immunogenicity, and Lot-Consistency Clinical Trial of a 6-Valent OspA-Based Lyme Disease Vaccine (VLA15)
NCT05477524 · View on ClinicalTrials.gov ↗
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.
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 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT05477524
The ClinicalTrials.gov registry entry for NCT05477524 describes a study currently listed as active not recruiting. It is categorized as Phase 3, 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 12,547 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Pfizer, which has 769 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 Lyme Disease appearing as the primary indexed condition, and to 2 interventions — of which Saline 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: NCT05477524 reports 20 study locations spanning 4 distinct geographic areas — top geographies include Massachusetts, Maryland, Connecticut. 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 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. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT05477524?
The interventions under investigation include: Saline (OTHER), VLA15 (BIOLOGICAL). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT05477524?
This trial is sponsored by Pfizer, which has 769 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
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.
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