Pfizer gives lyme vaccine a fifth dose — will it boost protection?

NCT ID NCT07500506

Recruiting now ⭐️ VACCINE ⭐️ Sponsor: Pfizer Source: ClinicalTrials.gov ↗

First seen Jun 27, 2026 · Last updated Jun 27, 2026

Summary

This study tests whether a fifth dose of Pfizer's Lyme disease vaccine (VLA15) is safe and boosts immunity in people who already received four doses. About 1,700 healthy volunteers aged 7 and older will get either the vaccine or a saltwater shot. Researchers will compare side effects and antibody levels over 12 months.

What this could mean

Our plain-language read of the trial. This is informational only — not medical advice or a prediction.

Active substance: VLA15 (Lyme disease vaccine)
What this could lead to: If successful, this could show that a booster dose of the Lyme disease vaccine provides continued protection against Lyme disease.
What could go wrong: This is a Phase 3 trial, but it only tests immune response and safety, not whether the vaccine actually prevents Lyme disease. The vaccine may not work as well in real-world conditions.

This is an AI summary of the original study and may miss details. Read our disclaimer.

Get updates

Get notified about this study

Our safety recommendation!

By submitting, you agree to our Terms of use

Conditions

The condition(s) this trial relates to.

Lyme disease prevention target

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

LYME DISEASE

Contacts and locations

Locations

Allegheny Health and Wellness Pavilion
RECRUITING

Erie, Pennsylvania, 16506, United States
Altoona Center For Clinical Research
RECRUITING

Duncansville, Pennsylvania, 16635, United States
Amherst Family Practice, P.C.
NOT_YET_RECRUITING

Winchester, Virginia, 22601, United States
Central Erie Primary Care
RECRUITING

Erie, Pennsylvania, 16508, United States
Diex Recherche Inc. Division Sherbrooke
RECRUITING

Sherbrooke, Quebec, J1L 0H8, Canada
Frontier Clinical Research, LLC
RECRUITING

Scottdale, Pennsylvania, 15683, United States
Frontier Clinical Research, LLC
RECRUITING

Smithfield, Pennsylvania, 15478, United States
Hunterdon Medical Center
NOT_YET_RECRUITING

Flemington, New Jersey, 08822, United States
Milestone Research Inc.
NOT_YET_RECRUITING

London, Ontario, N5W 6A2, Canada
Northeast Clinical Trials Group
RECRUITING

Scranton, Pennsylvania, 18510, United States
Northern Light Eastern Maine Medical Center
NOT_YET_RECRUITING

Bangor, Maine, 04401, United States
Northern Light Family Medicine and Residency Center
NOT_YET_RECRUITING

Bangor, Maine, 04401, United States
Preferred Primary Care Physicians
NOT_YET_RECRUITING

Uniontown, Pennsylvania, 15401, United States
Preferred Primary Care Physicians, Preferred Clinical Research (Ofc 18)
RECRUITING

Pittsburgh, Pennsylvania, 15236, United States
Preferred Primary Care Physicians, Preferred Clinical Research - St.Clair
NOT_YET_RECRUITING

Pittsburgh, Pennsylvania, 15243, United States
Robert Packer Hospital
RECRUITING

Sayre, Pennsylvania, 18840, United States
Smith Allergy & Asthma Specialists
RECRUITING

Horseheads, New York, 14845, United States
Smith Allergy and Asthma Specialists
RECRUITING

Cortland, New York, 13045, United States
Stouffville Medical Research Institute Inc.
NOT_YET_RECRUITING

Stouffville, Ontario, L4A 1H2, Canada
The University of Vermont Medical Center Inc.
NOT_YET_RECRUITING

Burlington, Vermont, 05401, United States
University of Massachusetts Chan Medical School
RECRUITING

Worcester, Massachusetts, 01655, United States
Velocity Clinical Research, Providence
NOT_YET_RECRUITING

East Greenwich, Rhode Island, 02818, United States

More trials for these conditions

Other studies related to the condition(s) this trial covers.