A Study to Learn About Different Dosing Schedules of a Lyme Disease Vaccine in Healthy Adults

NCT07226882 | Active Not Recruiting Phase 3 DMC FDA Drug

• 1 other identifier: C4601019
• Study Type: interventional
• Target: 207
• Locations: 1 country
• Sites: 6

Brief Summary

The purpose of this study is to learn about the safety and effects of the Lyme disease vaccine (called VLA15) when given at different time points. This study is seeking participants who:

• are generally healthy and between 18 and 44 years of age,
• have never had a vaccine for Lyme disease before,
• are not currently taking, or haven't recently taken, medicines like chemotherapy, blood products, or blood thinners, and
• 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 5 doses through a shot in the upper arm. Four doses will be the study vaccine (VLA15), and 1 dose will be saltwater. The study will compare the experiences of people receiving the study vaccine at different time points. This will help see if the study vaccine is safe and will help understand its effect on the body. Participants will take part in this study for about 2 years. During this time, the participants will have 11 planned visits - 8 will be at the study clinic and 3 will be done over the phone. The clinic visits may include having a health check, giving a small amount of blood (about 20 mL or 4 teaspoons), and getting the study vaccine or saltwater as a shot.

Conditions

Lyme Borreliosis

Keywords

Lyme disease; Lyme Borreliosis, Nervous System; Lyme; Lyme Disease Vaccine

Outcome Measures

Primary Outcomes (8)

• Geometric Mean Concentration (GMC) of Anti-Outer Surface Protein A (OspA) Immunoglobulin G (IgG)

  At 1 month after the fourth VLA15 dose

• Geometric Mean Fold Rise (GMFR) of Anti-Outer Surface Protein A (OspA) Immunoglobulin G (IgG) Concentrations

  Before the first dose to 1 month after the fourth VLA15 dose

• Sero-Response Rate Based on Anti-Outer Surface Protein A (OspA) Immunoglobulin G (IgG) Concentrations.

  Before the first dose to 1 month after the fourth VLA15 dose

• Percentage of Participants With Local Reactions For Each Group

  Within 7 days after each vaccination

• Percentage of Participants With Systemic Events For Each Group

  Within 7 days after each vaccination

• Percentage of Participants With Adverse Events (AEs) For Each Group

  Within 1 month after each vaccination

• Percentage of Participants With Serious Adverse Events (SAEs) For Each Group

  From the time the participant provides informed consent up to approximately 6 months after the last vaccination

• Percentage of Participants With Newly Diagnosed Chronic Medical Conditions (NDCMCs) For Each Group

  From the time the participant provides informed consent up to approximately 6 months after the last vaccination

Secondary Outcomes (3)

• Geometric Mean Concentration (GMC) of Anti-Outer Surface Protein A (OspA) Immunoglobulin G (IgG)

  At 1 month after the third VLA15 dose

• Geometric Mean Fold Rise (GMFR) of Anti-Outer Surface Protein A (OspA) Immunoglobulin G (IgG) Concentrations

  Before the first dose to 1 month after the third VLA15 dose

• Sero-Response Rate Based on Anti-Outer Surface Protein A (OspA) Immunoglobulin G (IgG) Concentrations.

  Before the first dose to 1 month after the third VLA15 dose

Study Arms (4)

Group 1

EXPERIMENTAL

Participants will receive 4 doses of VLA15 and 1 dose of placebo injection at different visits. Placebo will be given at Visit 3. Injections will be given as intramuscular shots.

Biological: VLA15; Biological: Placebo

Group 2

EXPERIMENTAL

Participants will receive 4 doses of VLA15 and 1 dose of placebo injection at different visits. Placebo will be given at Visit 5. Injections will be given as intramuscular shots.

Biological: VLA15; Biological: Placebo

Group 3

EXPERIMENTAL

Participants will receive 4 doses of VLA15 and 1 dose of placebo injection at different visits. Placebo will be given at Visit 7. Injections will be given as intramuscular shots.

Biological: VLA15; Biological: Placebo

Group 4

EXPERIMENTAL

Participants will receive 4 doses of VLA15 and 1 dose of placebo injection at different visits. Placebo will be given at Visit 9. Injections will be given as intramuscular shots.

Biological: VLA15; Biological: Placebo

Interventions

VLA15 BIOLOGICAL

Participants will receive IM injection of 6-valent OspA-based Lyme disease vaccine

Group 1; Group 2; Group 3; Group 4

Placebo BIOLOGICAL

Saline

Group 1; Group 2; Group 3; Group 4

Eligibility Criteria

• Age: 18 Years - 44 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• 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.

You may not qualify if:

• 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.
• Any prior Lyme disease vaccination, or recent or concurrent participation in a separate interventional study.
• Staff or direct family of the study site staff and Sponsor.

Sponsors & Collaborators

• Pfizer: lead

Study Sites (6)

IMA Clinical Research Warren

Warren Township, New Jersey, 07059, United States

Location

Smith Allergy and Asthma Specialists

Cortland, New York, 13045, United States

Location

Smith Allergy & Asthma Specialists

Horseheads, New York, 14845, United States

Location

Preferred Primary Care Physicians, Preferred Clinical Research (Ofc 18)

Pittsburgh, Pennsylvania, 15236, United States

Location

Northeast Clinical Trials Group

Scranton, Pennsylvania, 18510, United States

Location

Preferred Primary Care Physicians

Uniontown, Pennsylvania, 15401, United States

Location

Related Links

• To obtain contact information for a study center near you, click here.

MeSH Terms

Conditions

Lyme Disease; Lyme Neuroborreliosis

Condition Hierarchy (Ancestors)

Gram-Negative Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Infections; Borrelia Infections; Spirochaetales Infections; Tick-Borne Diseases; Vector Borne Diseases; Central Nervous System Bacterial Infections; Central Nervous System Infections; Central Nervous System Diseases; Nervous System Diseases

Study Officials

• Pfizer CT.gov Call Center

  Pfizer

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Third-party unblinded
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 13, 2025
• First Posted: November 12, 2025
• Study Start: November 19, 2025
• Primary Completion (Estimated): January 27, 2028
• Study Completion (Estimated): January 27, 2028
• Last Updated: May 6, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will share

Locations

US (6)