The purpose of this study is to learn about the safety effects of the Lyme disease vaccine (called VLA15), and its ability to protect people from Lyme disease after a 5th dose of the vaccine. This study is seeking participants who: * are generally healthy and 7 years of age and older, * have already been vaccinated with 4 doses of VLA15 (from the VALOR study), and have blood sample taken post dose 4. * are not currently taking, or haven't recently taken, medicines like chemotherapy, blood products, or blood thinners. * are not pregnant or breastfeeding and do not plan to become pregnant while receiving the study vaccine. All participants in this study will receive a total of 1 dose through a shot in the upper arm, either VLA15 or saline shot (saltwater). The study will compare the experiences of people receiving the study vaccine or saltwater shot. Participants will take part in this study for about 12 months. During this time, they will have 4 planned clinic visits. The clinic visits may include having a health check, giving a small amount of blood and getting the study vaccine or saltwater as a shot at the first visit.
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Percentage of participants reporting prespecified local reactions
Timeframe: Within 7 days following each study intervention administration
Percentage of participants reporting prespecified systemic events
Timeframe: Within 7 days following each study intervention administration
Percentage of participants reporting adverse events (AEs)
Timeframe: Through 1 month following study intervention administration
Percentage of participants reporting newly diagnosed chronic medical conditions (NDCMCs)
Timeframe: Through study completion, up to approximately 12 months.
Percentage of participants reporting serious adverse events (SAEs)
Timeframe: Through study completion, up to approximately 12 months.
Geometric mean ratio (GMR) of anti-OspA IgG concentrations for each serotype (ST1-ST6)
Timeframe: At 1 month after completion of Dose 5
Sero-response of anti-OspA IgG concentrations for each serotype (ST1-ST6).
Timeframe: At 1 month after completion of Dose 5
Pfizer CT.gov Call Center