Lyme Disease Vaccines in Development: What to Know About Current Candidates
New Lyme vaccines are in development
Protection may target ticks before transmission
Questions remain about long-term effectiveness
Lyme disease vaccines are once again being actively developed as Lyme disease rates continue to rise across the United States and Europe.
In 1998, the first Lyme disease vaccine, LYMErix, was introduced but later withdrawn from the market after several years because of poor sales and unresolved safety concerns.
The FDA did not establish a causal link between the vaccine and reported adverse events.
One of the major challenges now is creating vaccines that protect against multiple strains of Lyme disease found globally.
Pfizer/Valneva Vaccine (VLA15)
The Pfizer/Valneva candidate, VLA15, is currently the most advanced Lyme disease vaccine in development.
It targets Outer Surface Protein A (OspA), which is expressed by Borrelia burgdorferi while the bacteria remain inside the tick.
The goal is to generate antibodies that work inside the tick during feeding, blocking transmission before the bacteria enter the human body.
Once infection occurs, the bacteria shift protein expression from OspA to Outer Surface Protein C (OspC), meaning the vaccine is not expected to treat established infection.
VLA15 entered Phase 3 clinical trials after earlier studies suggested favorable immune responses.
Moderna mRNA Vaccines
Moderna is developing mRNA-based Lyme disease vaccines using technology similar to its COVID-19 vaccine platform.
Two vaccine candidates are under investigation:
- mRNA-1982: Targets the primary Borrelia species responsible for Lyme disease in the United States
- mRNA-1975: Targets multiple Borrelia species found in both the United States and Europe
Clinical trials are underway, with early-phase studies enrolling adult participants.
MassBiologics Monoclonal Antibody Approach
MassBiologics is pursuing a different strategy using monoclonal antibodies targeting OspA.
Unlike vaccines, which require time to generate immunity, monoclonal antibodies may provide more immediate protection following injection.
Preclinical studies in animal models demonstrated high levels of protection against infected ticks.
This approach differs from traditional vaccination because it delivers antibodies directly rather than stimulating the immune system to produce them over time.
Limitations and Considerations
Although these approaches are promising, several limitations remain:
- Long-term safety and effectiveness data are still pending
- Vaccines are designed to prevent infection—not treat existing disease
- Current candidates do not address coinfections such as Babesia or Bartonella
- Protection across multiple Borrelia strains remains a challenge
Frequently Asked Questions
Is there currently a Lyme disease vaccine available for humans?
At present, there is no commercially available Lyme disease vaccine for humans in the United States.
Does the Lyme vaccine treat active Lyme disease?
No. Current vaccine candidates are designed to prevent infection before transmission occurs and are not intended to treat established Lyme disease.
Would Lyme disease vaccines prevent coinfections?
Current vaccine candidates target Borrelia bacteria and are not designed to prevent coinfections such as Babesia, Bartonella, or Anaplasma.
Why was LYMErix withdrawn from the market?
LYMErix was withdrawn after poor sales and concerns about possible adverse effects, although the FDA did not establish a causal relationship between the vaccine and reported complications.
Clinical Takeaway
Lyme disease vaccine development has reemerged after decades of limited progress. While newer approaches show promise, long-term safety, effectiveness, and real-world performance data are still pending.
Until an effective vaccine is available, tick avoidance, prompt tick removal, and early symptom recognition remain the most reliable strategies for preventing Lyme disease.
At present, prevention strategies—including tick avoidance, prompt tick removal, and early recognition of symptoms—remain essential parts of Lyme disease prevention.
Related Articles
- Potential Barriers to Lyme Disease Vaccines
- Could Monoclonal Antibodies Prevent Lyme Disease Better Than a Vaccine?
- Would You Trust a Lyme Disease Vaccine?
- Lyme Disease Prevention Strategies
- Tick-Borne Coinfections: Complete Guide
References
- Guynup S. Lyme disease is spreading fast but a vaccine may be on the way. National Geographic. May 15, 2023.
- Pfizer. Pfizer and Valneva announce Lyme disease vaccine candidate demonstrates strong efficacy in Phase 3 VALOR trial. 2026.
Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.
Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention
As an LD vaccine participant 1995 Lymerix, Im sorry to read the misinformation that you publish about the FDA “not” finding adverse effects from the vaccine! It nearly killed me. I was told my glaring symptoms didn’t exist! Unless you want your life ruined, DO NOT volunteer as vaccine participant! Read my “Vaccine Volunteer ” article from 1997 in the Lyme Times & that tells the story. I had to sign legal agreements & the study docs did not uphold their own deal. Even the $350. for participating was taken from us. The VAERS promise.. was ignored after many attempts, etc.. etc.. Now nearly 30 years later they are just going to try again & they are NOT disclosing the truth to the public about what already happened! You’ve been warned, stay away! Its how I learned the hard, medicine is just a business now, nobody REALLY cares.
I am sorry you were sick from the LD vaccine. We are judge beginning understand the gap between what patients experience and what is reported to the study coordinators and VAERS. I added despite concerns to sentence. “The FDA was never able to confirm that the vaccine caused harm despite concerns.”
I had the Lymerix vaccine when it was available to the public, as did my family. We did not have a reaction that I can recall. What I do know is that years later after seeing a Functional Medicine Doctor for other issues I tested positive for Lyme. I have the test results to prove this to be so. So people need to be aware that they may test positive after taking this type of vaccine. Where this becomes an issue, a person won’t know if they actually were bitten and need an antibiotic or if their test results is due to having the vaccine.** There was never any information as to how long the Lymerix shot was able to provide immunity.
The Lymerix vaccine was OspA. It was not made of live components & could not have given you LD. The docs refused to share my original test results as I was represented by NY attorney. I was patient of chief of infectious at BU for 20 years & tested positive the entire 2 decades, even after a year+ of oral antibiotics & then 4 months of a long picc line, self infusing 2 x’s a day! I had 9 sugeries & had organs removed… I was in phase IV of study & went to NIH in Maryland to speak to Physician panel with 19 others from across the country who also had adverse effects from vaccine. We won the clash action suit for 450 people! I was timed out & received $0.00, but… that vaccine was taken OFF the market!
Being 13 generation Cape Codder, literally Wampanoag & Mayflower, I was constantly in the woods & know (now) I already had LD. It was suspected I was in dormant situation & the vax agitated, aggrevated & exasperated my situation. It was maddening to be denied! And everybody loses when medicine lies!
It can be difficult to determine if a Lyme disease test is positive from the vaccine or from Lyme disease. The western blot was introduced with the hope that they could tell the difference. Unfortunately, the western blot test has its own problems. The vaccine manufacturer thought the vaccine might need to be given yearly to help.