Safety Study of a Vaccine to Help Protect Against Lyme Disease in Healthy Children
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Phase
Phase 3
Status
Completed
Study type
Interventional
Design
Randomized · Quadruple · Other
Enrollment
3,547actual
Sites
65
Country
United States
Every value on this page is a field the sponsor filed with ClinicalTrials.gov, reproduced. Dates are their own estimates, revised as a study runs, unless the registry marks them actual. sources →
Source: ClinicalTrials.gov, retrieved 2026-08-19
Dates
each axis at the precision it was filed, with the registry's own basis| Date | Filed | Basis | What it is |
|---|---|---|---|
| Start | 2022-12-12 | actual | When the study began enrolling |
| Primary completion | 2025-07-21 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2025-07-21 | actual | The whole study's end, after follow-up |
| First posted | 2022-12-02 | actual | When this record first appeared on the registry |
| Results posted | 2026-05-07 | actual | When the sponsor posted results to the registry |
| Record updated | 2026-05-07 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- Lyme Disease
Interventions
- Biological: VLA15 — also filed as PF-07307405
- Other: Normal Saline
Primary outcomes
what the primary-completion date above is the date OFPercentage of Participants With at Least 1 Local Reaction of Any Grade for up to 7 Days Following Study Vaccination 1
measured From Day 1 through Day 7 after Study Vaccination 1 (Vaccination on Day 1, Month 0)
Percentage of Participants With at Least 1 Local Reaction of Any Grade for up to 7 Days Following Study Vaccination 2
measured From Day 1 through Day 7 after Study Vaccination 2 (Vaccination on Day 1, Month 2)
Percentage of Participants With at Least 1 Local Reaction of Any Grade for up to 7 Days Following Study Vaccination 3
measured From Day 1 through Day 7 after Study Vaccination 3 (Vaccination on Day 1, Month 6)
Percentage of Participants With at Least 1 Local Reaction of Any Grade for up to 7 Days Following Study Vaccination 4 (Booster Dose)
measured From Day 1 through Day 7 after Study Vaccination 4 (Vaccination on Day 1, Month 18)
Percentage of Participants With at Least 1 Local Reaction of Any Grade for up to 7 Days After Any Study Vaccination
measured From Day 1 through Day 7 after any study vaccination
Percentage of Participants With at Least 1 Systemic Event of Any Grade for up to 7 Days Following Study Vaccination 1
measured From Day 1 through Day 7 after Study Vaccination 1 (Vaccination on Day 1, Month 0)
Percentage of Participants With at Least 1 Systemic Event of Any Grade for up to 7 Days Following Study Vaccination 2
measured From Day 1 through Day 7 after Study Vaccination 2 (Vaccination on Day 1, Month 2)
Percentage of Participants With at Least 1 Systemic Event of Any Grade for up to 7 Days Following Study Vaccination 3
measured From Day 1 through Day 7 after Study Vaccination 3 (Vaccination on Day 1, Month 6)
Percentage of Participants With at Least 1 Systemic Event of Any Grade for up to 7 Days Following Study Vaccination 4 (Booster Dose)
measured From Day 1 through Day 7 after Study Vaccination 4 (Vaccination on Day 1, Month 18)
Percentage of Participants With at Least 1 Systemic Event of Any Grade for up to 7 Days After Any Study Vaccination
measured From Day 1 through Day 7 after any study vaccination
Percentage of Participants With AEs Through 1 Month Following Study Vaccination 1
measured From Day 1 through 1 Month after Study Vaccination 1 (Vaccination on Day 1, Month 0)
Percentage of Participants With AEs Through 1 Month Following Study Vaccination 2
measured From Day 1 through 1 Month after Study Vaccination 2 (Vaccination on Day 1, Month 2)
Percentage of Participants With AEs Through 1 Month Following Study Vaccination 3
measured From Day 1 through 1 Month after Study Vaccination 3 (Vaccination on Day 1, Month 6)
Percentage of Participants With AEs Through 1 Month Following Study Vaccination 4 (Booster Dose)
measured From Day 1 through 1 Month after Study Vaccination 4 (Vaccination on Day 1, Month 18)
Percentage of Participants With AEs Through 1 Month Following Any Study Vaccination
measured From Day 1 through 1 Month after any study vaccination
Percentage of Participants With Newly Diagnosed Chronic Medical Condition (NDCMCs) Throughout the Study
measured Throughout the study (from study vaccination 1 through 6 months post study Vaccination 4 [Booster dose]: maximum up to 24 months)
Percentage of Participants With Serious Adverse Events (SAEs) Throughout the Study
measured Throughout the study (from study vaccination 1 through 6 months post study Vaccination 4 [Booster dose]: maximum up to 24 months)
Posted documents
hosted by the registry — we link, never re-serveStudy Protocolposted 2022-07-25 · 10.7 MB · Prot_000.pdf
Statistical Analysis Planposted 2025-08-01 · 329 KB · SAP_001.pdf
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