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Phase 2 Study Of VLA15, A Vaccine Candidate Against Lyme Borreliosis, In A Healthy Pediatric And Adult Study Population
NCT04801420 · View on ClinicalTrials.gov ↗
Study Summary
VLA15-221 is a Phase 2 study, which will be conducted in two parts: Main Study Phase (Part A) and Booster Phase (Part B). The study will compare the safety and immunogenicity of two different primary immunization schedules applying three (Month 0-2-6) or two (Month 0- 6) vaccinations. Within the study, 600 healthy subjects aged 5-65 years will be included. Subjects with a history of Lyme borreliosis (previous infection with Borrelia) as well as Borrelia naïve subjects will be enrolled. Study duration per subject will be a maximum of 50 months per subject.
Conditions Studied
Interventions
- BIOLOGICAL Placebo
- BIOLOGICAL VLA15
Study Locations (20)
New York
- Meridian Clinical Research LLC — Binghamton
- Pfizer Vaccine Research and Development — Pearl River
- Rochester Clinical Research, Inc. — Rochester
- Richmond Behavioral Associates — Staten Island
- Advantage Clinical Trials — The Bronx
Connecticut
- New England Research Associates — Bridgeport
- Stamford Therapeutics Consortium — Stamford
- Chase Medical Research, LLC — Waterbury
- Pediatric Associates of Conn. PC — Waterbury
Pennsylvania
- Allegheny Health and Wellness Pavilion — Erie
- Liberty Family Practice — Erie
- Lockman & Lubell Pediatric Associates — Fort Washington
Rhode Island
- Hasbro Children's Hospital — Providence
- Rhode Island Hospital — Providence
- The Miriam Hospital — Providence
New Jersey
- Foundation Pediatrics — East Orange
- Med Clinical Research Partners, LLC — Irvington
Massachusetts
- Quest Diagnostics — Marlborough
Minnesota
- Clinical Research Institute, Inc. — Minneapolis
Ohio
- Velocity Clinical Research, Inc. — Cleveland
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 625 participants |
| Start Date | 2021-03-08 |
| Est. Completion | 2025-07-02 |
| Phase | Phase 2 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT04801420
The ClinicalTrials.gov registry entry for NCT04801420 describes a study currently listed as completed. It is categorized as Phase 2, 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 625 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 Borreliosis appearing as the primary indexed condition, and to 2 interventions — of which Placebo 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: NCT04801420 reports 20 study locations spanning 8 distinct geographic areas — top geographies include New York, Connecticut, Pennsylvania. 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 NCT04801420 about?
NCT04801420 is a clinical study titled "Phase 2 Study Of VLA15, A Vaccine Candidate Against Lyme Borreliosis, In A Healthy Pediatric And Adult Study Population". VLA15-221 is a Phase 2 study, which will be conducted in two parts: Main Study Phase (Part A) and Booster Phase (Part B). The study will compare the safety and immunogenicity of two different primary immunization schedules applying three (Month 0-2-6) or two (Month 0- 6) vaccinations. Within the stu...
What is the current status of trial NCT04801420?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 625 participants. The study started on 2021-03-08. Estimated completion is 2025-07-02.
What conditions does trial NCT04801420 study?
This clinical trial studies the following conditions: Lyme Borreliosis. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT04801420?
The interventions under investigation include: Placebo (BIOLOGICAL), VLA15 (BIOLOGICAL). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT04801420?
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 NCT04801420 being conducted?
This trial has 20 study locations across Connecticut, Massachusetts, Minnesota, New Jersey, New York. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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