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NCT03769194 · ClinicalTrials.gov registry record · Phase 2
Immunogenicity and Safety Study of a Vaccine Against Lyme Borreliosis, in Healthy Adults Aged 18 to 65 Years. Randomized, Controlled, Observer-blind Phase 2 Study.
A Phase 2 study, sponsored by Pfizer.
- Completed
- Registry status
- Phase 2
- Development phase
- 572
- Enrollment target
NCT03769194: Completed Phase 2 study, sponsored by Pfizer.
NCT03769194 is a Phase 2 study that has completed, run by Pfizer. The registered enrollment target is 572 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (330% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03769194, a Phase 2 study, has completed, sponsored by Pfizer.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 572 participants
- Enrollment target
Study Summary
This is a randomized, observer-blind, placebo controlled, multicenter Phase 2 study conducted in two study phases: a run-in phase and a main study phase. The study was investigated 3 doses of a multivalent OspA (Outer Surface Protein A) based Lyme vaccine (VLA15) in healthy adults aged 18 to 65 years of age. Study participants received 3 immunizations of the vaccine at a monthly interval. The study assessed the immune response as well as the safety profile of the vaccine.
Primary Outcome
GMTs (Geometric Mean Titers) for IgG (Immunoglobulin G) against each OspA (Outer Surface Protein A) serotype ST1 to ST6, determined by ELISA at Day 85. GMTs are calculated based on the number of subjects with non-missing results.
Interventions
- BIOLOGICAL Placebo
- BIOLOGICAL VLA15
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 572 participants |
| Start Date | 2018-12-17 |
| Est. Completion | 2020-10-02 |
| Phase | Phase 2 |
What the finished NCT03769194 record still lists
NCT03769194 is an interventional study that assigns participants to a tested intervention. The registered 572 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 (330% higher).
The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.
NCT03769194 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03769194 about?
NCT03769194 is a clinical study titled "Immunogenicity and Safety Study of a Vaccine Against Lyme Borreliosis, in Healthy Adults Aged 18 to 65 Years. Randomized, Controlled, Observer-blind Phase 2 Study.". This is a randomized, observer-blind, placebo controlled, multicenter Phase 2 study conducted in two study phases: a run-in phase and a main study phase. The study was investigated 3 doses of a multivalent OspA (Outer Surface Protein A) based Lyme vaccine (VLA15) in healthy adults aged 18 to 65 year...
What is the current status of trial NCT03769194?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 572 participants. The study started on 2018-12-17. Estimated completion is 2020-10-02.
What interventions are being tested in trial NCT03769194?
The interventions under investigation include: Placebo (BIOLOGICAL), VLA15 (BIOLOGICAL).
Who is sponsoring clinical trial NCT03769194?
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 NCT03769194's enrollment target sits among peer trials
572 59th of 2000 higher than 1,942 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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