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NCT05634811 · ClinicalTrials.gov registry record · Phase 3
Safety Study of a Vaccine to Help Protect Against Lyme Disease in Healthy Children
A Phase 3 study, sponsored by Pfizer.
- Completed
- Registry status
- Phase 3
- Development phase
- 3,547
- Enrollment target
NCT05634811: Completed Phase 3 study, sponsored by Pfizer.
NCT05634811 is a Phase 3 study that has completed, run by Pfizer. The registered enrollment target is 3,547 participants, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (359% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05634811, a Phase 3 study, has completed, sponsored by Pfizer.
- COMPLETED
- Registry status
- Phase 3
- Development phase
- 3,547 participants
- Enrollment target
Study Summary
This study is to understand if the study vaccine (called VLA15) is safe in healthy children. We are looking for children who: * are healthy * are age 5 through 17 * have not been diagnosed with any form of Lyme disease in the past * have not received any vaccines for Lyme disease in the past Lyme disease happens most often in children of this age. The study vaccine may be used potentially to help prevent Lyme disease. The goal of this study is to get more information about the safety of the study vaccine in this age group. Participants will be in this study for about 2 years. During that time, they will receive VLA15 or placebo (sterile saltwater solution) by a "shot" in the arm. We will compare experience of children receiving VLA15 to those receiving the placebo. Participants will not know whether they get VLA15 or placebo. Everyone participating in this study will: * get the shots in a clinic or in a hospital office * receive a total of 4 shots * receive the first 3 shots within 6 months * receive the last shot about 1 year afterwards * need to come to the trial site for 6 planned visits; 4 of these are vaccination visits and 2 are follow-up visits. We will contact you by phone 1 time every year during the study to monitor your experience. You may have extra visits if you experience a severe reaction after a vaccine dose.
Primary Outcome
Local reactions included pain at injection site, redness and swelling and were recorded by participants in the electronic dairy (e-diary) or by investigators in case report form (CRF) after vaccination. Local reactions were graded per the 'Local Reaction Grading Scale' per protocol based on Center for Biologics Evaluation and Research (CBER) toxicity guidelines. Percentage of participants with at least 1 local reaction of any grade were reported in this outcome measure.
Interventions
- OTHER Normal Saline
- BIOLOGICAL VLA15
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 3,547 participants |
| Start Date | 2022-12-12 |
| Est. Completion | 2025-07-21 |
| Phase | Phase 3 |
What the finished NCT05634811 record still lists
NCT05634811 is an interventional study that assigns participants to a tested intervention. Its 3,547 participants enrollment target places it among the larger protocols in the corpus, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (359% higher).
The record links to 0 conditions, and to 2 interventions - of which Normal Saline is the first listed.
NCT05634811 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT05634811 about?
NCT05634811 is a clinical study titled "Safety Study of a Vaccine to Help Protect Against Lyme Disease in Healthy Children". This study is to understand if the study vaccine (called VLA15) is safe in healthy children. We are looking for children who: * are healthy * are age 5 through 17 * have not been diagnosed with any form of Lyme disease in the past * have not received any vaccines for Lyme disease in the past Lyme...
What is the current status of trial NCT05634811?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 3,547 participants. The study started on 2022-12-12. Estimated completion is 2025-07-21.
What interventions are being tested in trial NCT05634811?
The interventions under investigation include: Normal Saline (OTHER), VLA15 (BIOLOGICAL).
Who is sponsoring clinical trial NCT05634811?
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 NCT05634811's enrollment target sits among peer trials
3,547 68th of 2000 higher than 1,933 of 2,000 other Phase 3 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 3 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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