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NCT04801420 · ClinicalTrials.gov registry record · Phase 2
Phase 2 Study Of VLA15, A Vaccine Candidate Against Lyme Borreliosis, In A Healthy Pediatric And Adult Study Population
A Phase 2 study of Lyme Borreliosis, sponsored by Pfizer.
- Completed
- Registry status
- Phase 2
- Development phase
- 625
- Enrollment target
- 20
- Study locations
NCT04801420: Completed Phase 2 study of Lyme Borreliosis, sponsored by Pfizer.
NCT04801420 is a Phase 2 study of Lyme Borreliosis that has completed, run by Pfizer. The registered enrollment target is 625 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (370% higher). The trial reports 20 study locations across 8 states. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04801420, a Phase 2 study of Lyme Borreliosis, has completed, sponsored by Pfizer.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 625 participants
- Enrollment target
- 20
- Study locations
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.
Primary Outcome
Participants or their legal guardians were required to record any solicited local and systemic adverse events in the electronic diary. Solicited symptoms were pre-defined symptoms which were collected via an electronic diary. Solicited local AEs included pain, tenderness, erythema (redness), swelling and induration (hardening). Solicited systemic AEs included headache, muscle pain, joint pain, nausea, vomiting, fatigue and fever. Two-sided 95% confidence intervals were calculated according to Al
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 |
What the finished NCT04801420 record still lists
NCT04801420 is an interventional study that assigns participants to a tested intervention. The registered 625 participants enrollment target is mid-sized for trials with a published cap, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (370% higher).
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.
NCT04801420 names 20 study sites across 8 states, led by New York, Connecticut, Pennsylvania.
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.
What interventions are being tested in trial NCT04801420?
The interventions under investigation include: Placebo (BIOLOGICAL), VLA15 (BIOLOGICAL).
Who is sponsoring clinical trial NCT04801420?
This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.
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.
Learn More About Clinical Trials
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Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.
Where NCT04801420's enrollment target sits among peer trials
625 52nd of 2000 higher than 1,949 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 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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