Can we prevent Lyme disease? A vaccine for Lyme disease has now progressed to a large human trial. Valneva’s VLA15 vaccine, in joint development with Pfizer, is designed to be effective against all strains of Borrelia, so the trial will include 6,000 people from both Europe and the USA. Read Valneva’s announcment.
Small trials of this vaccine have already shown good effectiveness and safety both in adults and children. Because the trial needs vaccinated people to be naturally exposed to Lyme disease, to check it really does prevent disease, it will include people in areas of high prevalence of Lyme disease including Finland, Germany, the Netherlands, Poland, Sweden and the United States. So not the UK, as the level of infection in our ticks is much lower than those countries.
Two previous vaccines were developed for American Lyme disease back in the 1990s. ImuLyme relied on booster doses, and didn’t get beyond trials. The more successful vaccine, LYMERix, came to market and was quite widely used as it clearly worked. However, there was a lot of publicity about side effects of arthritis and facial paralysis and the general public failed to understand that these were no more common than in the general population. This bad publicity led to a downturn in sales and eventually LymeRix was discontinued.
VLA15 works by raising antibodies that, when taken in by the tick when it first attaches to a human, inhibit the Borrelia bacteria’s ability to move from the tick gut into its salivary glands and into the person. We now have to wait for some time while this new large trial takes place and the data is analysed. If the product is safe and effective then it is suggested a product may be launched in 2025.
A vaccine is likely to be useful for those people at high risk of tick bites in areas where Lyme disease is present. LDA is often contacted by people such as forestry workers, botanical surveyors, farmers, regular countryside users and others asking how to protect themselves. Repellents, either on skin, or impregnated clothing, are helpful, but the repellents wear off and a determined tick can walk over onto an unprotected area of skin.
We look forward to updates on the vaccine progress.