Lyme Disease Vaccine for Lyme Disease

No longer recruiting at 29 trial locations

Age: Any Age

Sex: Any

Trial Phase: Phase 2

Sponsor: Pfizer

Must not be taking: Anticoagulants, Immuno-suppressive therapy

Disqualifiers: Chronic Lyme, Autoimmune, Malignancy, others

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: 6

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a new vaccine, VLA15, to evaluate its effectiveness and safety in preventing Lyme disease. The study explores two different vaccination schedules to determine the best approach for building immunity. Participants must be in good health and not have received recent Lyme disease treatment. This includes individuals who have had Lyme disease before and those who have not. The trial involves receiving either the vaccine or a placebo over several months. As a Phase 2 trial, the research focuses on measuring the treatment's effectiveness in an initial, smaller group of people.

Will I have to stop taking my current medications?

The trial protocol does not specify if you need to stop taking your current medications. However, if you are on immuno-suppressive therapy, anticoagulants, or have received any other vaccines or investigational drugs recently, you may need to stop those before joining the trial.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that VLA15, the Lyme disease vaccine candidate, has been well-tolerated in studies. Findings indicate that VLA15 is safe for people of all ages. Recipients of the vaccine developed a strong immune response, enhancing their ability to fight off Lyme disease.

Trials have reported no major safety issues. Even after additional booster doses, VLA15 remained safe and effective. This suggests the vaccine is dependable for both children and adults. Overall, VLA15 has demonstrated a positive safety profile, making it a promising option for preventing Lyme disease. ^{1 2 3 4 5}

Why are researchers excited about this study treatment for Lyme disease?

Researchers are excited about VLA15 as a potential Lyme disease vaccine because it targets the outer surface protein A (OspA) of Borrelia bacteria, which is a unique approach compared to current treatments. Most Lyme disease treatments rely on antibiotics like doxycycline, amoxicillin, or cefuroxime axetil, which are effective only after infection has occurred. VLA15, on the other hand, aims to prevent the disease entirely by stimulating the immune system to recognize and attack the bacteria before an infection can take hold. This preventive strategy could significantly reduce the incidence of Lyme disease, offering a proactive solution rather than a reactive one.

What evidence suggests that this trial's treatments could be effective for Lyme disease?

Research has shown that VLA15, a Lyme disease vaccine, could help prevent the disease. One study found that three doses of the vaccine were 71% effective in real-world conditions. The immune response, particularly in children and teens, was strong after the second dose. The vaccine is considered safe, and the immune response improved with a booster dose. In this trial, participants may receive VLA15 in different dosing schedules to evaluate its effectiveness. If VLA15's effectiveness reaches or exceeds 76%, it could match or surpass previous Lyme disease vaccines. Overall, current evidence supports VLA15 as a promising option for preventing Lyme disease. ^{2 4 6 7 8}

Who Is on the Research Team?

Pfizer CT.gov Call Center

Principal Investigator

Pfizer

Are You a Good Fit for This Trial?

Healthy individuals aged 5-65, with or without a past Lyme disease infection, can join this trial. They must understand and agree to the study's procedures, attend all visits, and be reachable by phone. Women of childbearing age need a negative pregnancy test and must use birth control during the study.

Inclusion Criteria

If subject is of childbearing potential: Subject has a negative serum pregnancy test at screening (Visit 0) and agrees to employ adequate birth control measures according to following timelines:

I am in the booster phase, 5 months post-booster dose.

I can be reached by phone and can participate in the study for its entire duration.

Exclusion Criteria

I have a bleeding disorder or have taken blood thinners in the last 3 weeks.

I have an immune system issue or took immune-suppressing drugs recently.

I do not have any health issues that could affect my participation in the study.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Main Study Phase (Part A)

Participants receive VLA15 or placebo vaccinations at Month 0, 2, and 6

6 months

3 visits (in-person)

Booster Phase (Part B)

Eligible participants receive booster injections with VLA15 or placebo at Month 18, 30, and 42

24 months

3 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 months

What Are the Treatments Tested in This Trial?

Interventions

• Placebo
• VLA15

Trial Overview The VLA15-221 trial is testing VLA15, a vaccine candidate for Lyme disease. Participants will receive either three shots (at months 0, 2, and 6) or two shots (months 0 and 6), compared to placebo. The main phase lasts up to 19 months with an optional booster phase extending it.

How Is the Trial Designed?

Group I: Part A+B - Group 2 Experimental Treatment 2 Interventions

Part A: VLA15 at Month 0 and 6, placebo at Month 2 Part B: VLA15 at Month 18, 30 and 42

Group II: Part A+B - Group 1 Experimental Treatment 2 Interventions

Part A: VLA15 at Month 0, 2 and 6 Part B: VLA15 at Month 18, 30 and 42

Group III: Part A+B - Group 3 Placebo Group 1 Intervention

Part A: Placebo at Month 0, 2 and 6 Part B: Placebo at Month 18, 30 and 42

Who Is Running the Clinical Trial?

Pfizer

Lead Sponsor

Trials

4,712

Recruited

50,980,000+

Known For

Vaccine Innovations

Top Products

Viagra, Zoloft, Lipitor, Prevnar 13

Albert Bourla

Pfizer

Chief Executive Officer since 2019

PhD in Biotechnology of Reproduction, Aristotle University of Thessaloniki

Patrizia Cavazzoni

Pfizer

Chief Medical Officer

MD from McGill University

Valneva Austria GmbH

Industry Sponsor

Trials

46

Recruited

59,100+

Citations

1. valneva.com valneva.com/wp-content/uploads/2025/09/2025_09_02_VLA15-221_m42_PR_EN_Final-1.pdf

Valneva Reports Further Positive Phase 2 Safety and ... The strong anamnestic immune response and favorable safety profile following a third booster dose were consistent with those reported after ...

2. thelancet.com thelancet.com/journals/laninf/article/PIIS1473-3099(25)00160-4/fulltext?rss=yes

Lyme borreliosis vaccine VLA15 tested safe and ... If the efficacy of VLA15 meets or potentially exceeds the 76% observed in the phase 3 study of LYMErix,

3. sciencedirect.com sciencedirect.com/science/article/abs/pii/S1473309925000921

Immunogenicity and safety of different immunisation ... Immune responses in children and adolescents after the second dose of VLA15 when administered with a 0–2–6-month schedule were at least as high as those in ...

4. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8364756/

Clinical Effectiveness of Lyme Vaccine: A Matched Case– ... We found ≥3 doses to be 71% effective against Lyme disease. This is the first study to show that the Lyme vaccine is effective in a real-world setting.

5. pfizer.com pfizer.com/news/press-release/press-release-detail/valneva-and-pfizer-report-further-positive-phase-2-booster

Valneva and Pfizer Report Further Positive Phase 2 ... The safety and tolerability profile of VLA15 after a second booster dose was comparable to the profile observed after the first booster.

6. valneva.com valneva.com/press-release/valneva-reports-further-positive-phase-2-safety-and-immunogenicity-results-for-lyme-disease-vaccine-candidate/

Valneva Reports Further Positive Phase 2 Safety and ... Strong immune response after third yearly booster dose in children and adults · Significant anamnestic antibody response across all six serotypes ...

7. thelancet.com thelancet.com/journals/laninf/article/PIIS1473-3099(24)00372-4/abstract

Immunogenicity and safety of an 18-month booster dose ... A booster dose of VLA15 is safe and induces substantial anamnestic immune responses against all six OspA serotypes. As with previously ...

8. pfizer.com pfizer.com/news/press-release/press-release-detail/phase-3-valor-lyme-disease-trial-valneva-and-pfizer

Phase 3 VALOR Lyme Disease Trial: Valneva and ... VLA15 has shown a favorable safety profile across all dose and age groups in all clinical trials to date.2,3 No safety concerns have been ...