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.
Participants who are healthy as determined by medical history and clinical judgment.
Participants willing and able to comply with all scheduled visits, IP receipt, and other procedures throughout the study.
Able to provide Informed Consent.
Participants must have received 4 doses of VLA15 in the C4601003 study, and have a V7 blood sample available.
Pregnant or breastfeeding participants.
Allergies or contraindications to vaccines or their components.
Health issues including: blood clotting deficiencies, immunodeficiencies, bone marrow disorder, or uncontrolled psychiatric conditions.
Receipt of therapies to treat malignancies, blood/plasma products and immunoglobulins, systemic corticosteroids and immunosuppressants, or anticoagulant therapy in recent medical history.
Parallel
VLA15
Biological/VaccineVLA15 injection IM
Placebo
Biological/VaccineSaline Injection
Percentage of participants reporting prespecified local reactions
Percentage of participants reporting prespecified systemic events
Percentage of participants reporting adverse events (AEs)
Percentage of participants reporting newly diagnosed chronic medical conditions (NDCMCs)
Geometric mean ratio (GMR) of anti-OspA IgG concentrations for each serotype (ST1-ST6)
Objective to determine non-inferiority of Dose 5 compared to Dose 4 in adult participants when there is a 1 year gap between Dose 4 and Dose 5.
Geometric mean ratio (GMR) of anti-OspA IgG concentrations for each serotype (ST1-ST6)
Objective to determine non-inferiority of Dose 5 compared to Dose 4 in all participants when there is a 2 year gap between Dose 4 and Dose 5.
Geometric mean ratio (GMR) of anti-OspA IgG concentrations for each serotype (ST1-ST6)
Objective to describe the immune response following Dose 5 compared to Dose 4 in pediatric participants when there is a 1 year gap between Dose 4 and Dose 5.
Geometric mean ratio (GMR) of anti-OspA IgG concentrations for each serotype (ST1-ST6)
Objective to describe the immune response following Dose 5 compared to Dose 4 in all participants (by age group) when there is a 2 year gap between Dose 4 and Dose 5.
