Are There Vaccine Options for Lyme Disease?
Key takeaways:
The first and only Lyme disease vaccine was discontinued in 2002. No other vaccines have been approved since.
There’s currently a Lyme disease vaccine in phase 2 clinical trials. It’s expected to enter phase 3 clinical trials in 2022.
A medication for pre-exposure prophylaxis (PrEP) against Lyme disease has started human trials. It could potentially be given before tick season every year to prevent infection.
Lyme disease is a bacterial infection spread through tick bites. It usually responds well to antibiotics if treated right away. But some people can experience long-term symptoms for upwards of 12 months, even after treatment.
About 30,000 Lyme disease cases are reported every year. But it’s estimated that number could actually be closer to 476,000 annual cases. And even though treatments are available, it’s better to prevent an infection from happening in the first place. This is where vaccines and other prevention strategies can help.
Here we’ll cover the history and future of Lyme disease vaccines, including when one might be available.
Has a vaccine for Lyme disease been FDA approved?
Yes. In 1998, the FDA approved LYMERix, the first and only Lyme disease vaccine. Another vaccine, called ImuLyme, was also being studied at the time but never applied for approval
LYMERix was recommended for people ages 15 to 70 with exposure risk who lived or worked in areas with high rates of Lyme disease (endemic areas). It wasn’t recommended for people in low risk areas, children under age 15, or adults over age 70.
The vaccine was given as a three-dose vaccine. You would receive your first shot, followed by your second dose one month later. Your third dose was 12 months after your first shot.
LYMERix worked by targeting a protein on the outside of the bacteria that causes Lyme disease. It triggered the immune system to make antibodies against this protein, which is found on the bacteria in the tick’s gut as it starts to feed on your blood.
In clinical trials, the vaccine was found to be 49% effective against Lyme disease after two doses. And it was 76% effective after three doses.
Why was LYMERix discontinued?
Over 1 million doses of LYMERix had been given the year following approval. This significantly lowered the number of new Lyme disease cases in the U.S.
During that time, concerns about vaccine safety emerged. But these concerns weren’t supported by the FDA’s findings upon investigation. And yet, the number of people getting the vaccine dropped significantly. Because of this, LYMERix was discontinued in 2002.
Are you still protected if you received LYMERix?
According to the Centers for Disease Control and Prevention (CDC), you may not be protected against Lyme disease if you previously received LYMERix. This is because protection from the vaccine can go down over time.
Are any Lyme disease vaccines being researched?
There were a few limitations with LYMERix. For one, it only protected against North American strains of the bacteria that causes Lyme disease. It also took three doses over at least 12 months to reach 76% effectiveness. And it was unclear how long protection would last.
The good news is that vaccine development and prevention efforts are working to address some of these issues. More on that below.
Vaccines
Pfizer and Valneva, a French vaccine company, are studying a Lyme disease vaccine in people ages 18 to 65. Their vaccine works by targeting the same protein as LYMERix. But unlike LYMERix, it protects against North American and European strains of the bacteria. It was also made without the components thought to be linked to LYMERix’s safety concerns.
The study’s vaccine is also given in three doses. This includes an initial dose, a second dose at 2 months, and a third dose at 6 months. Participants were also given the opportunity to receive a booster dose at 18 months. This is because protection has been shown to go down over time.
The vaccine is currently in phase 2 clinical trials. Phase 2 trials study the immune response triggered by the vaccine and its safety. The companies expect to begin phase 3 clinical trials in 2022. Phase 3 trials are the last step before a company can apply for FDA approval.
Pre-exposure prophylaxis
In addition to vaccines, other prevention strategies are being studied for Lyme disease. This includes pre-exposure prophylaxis (PrEP). PrEP is when you take medications before exposure to a bacteria or virus to prevent infection.
MassBiologics is studying a single-dose medication for PrEP against Lyme disease in adults ages 19 to 65. The medication would likely be given before tick season every year to provide seasonal protection.
The study medication is an anti-Lyme monoclonal antibody. Monoclonal antibodies are lab-made proteins that target certain substances. In this case, the antibodies would attack the bacteria that causes Lyme disease.
Studies in humans are just getting started. The study medication is currently in phase 1 clinical trials, which studies safety and dosing in a small group of people. The study is expected to be completed in 2022.
Is a Lyme disease vaccine necessary?
The best way to protect yourself from Lyme disease is by avoiding tick bites. While not all ticks transmit Lyme disease, it’s still important to take precautions if you find yourself in areas where ticks live. This includes avoiding brushy or wooded areas, wearing proper clothing and gear, and using insect repellent. And it’s important to check yourself for ticks after being outdoors.
That said, a Lyme disease vaccine could add another layer of protection. It’s not a replacement for the precautions listed above. But the combination could help to lower the number of annual Lyme disease cases.
This was the case after LYMERix was approved — new infections in vaccinated adults dropped by nearly 80%. In other words, a vaccine can still make a significant difference.
The bottom line
LYMERix was the first and only Lyme disease vaccine available in the U.S. It was 76% effective against Lyme disease after the third dose. It was discontinued due to low demand after potential safety concerns were being investigated.
A new Lyme disease vaccine is currently being researched in clinical trials. It’s expected to begin phase 3 trials next year. A medication for PrEP against Lyme disease is also being studied. But it’s just started human trials this year.
It’ll be a few years before vaccine and PrEP options are available. So, it’s important to protect yourself from tick bites to prevent Lyme disease, especially if you live or work in areas where it's common.
Why trust our experts?
References
Centers for Disease Control and Prevention. (1999). Recommendations for the use of Lyme disease vaccine recommendations of the advisory committee on immunization practices.
Centers for Disease Control and Prevention. (2020). Preventing tick bites.
Centers for Disease Control and Prevention. (2021). Data and surveillance | Lyme disease.
Centers for Disease Control and Prevention. (2021). Treatment for erythema migrans | Lyme disease.
Clinicaltrials.gov. (2021). First clinical study of the safety and blood levels of a human monoclonal antibody (2217LS) against Lyme disease bacteria in healthy people.
Food and Drug Administration. (2018). Step 3: Clinical research.
National Cancer Institute. Definition of monoclonal antibody.
National Institute of Allergy and Infectious Diseases. (2018). Lyme disease vaccines.
Nigrovic, L.E., et al. (2007). The Lyme vaccine: a cautionary tale. Epidemiology and Infection.
Pfizer. (2021). Valneva and Pfizer report further positive phase 2 results, including booster response, for Lyme disease vaccine candidate.
