Pfizer and Valneva have announced the commencement of a Phase 3 clinical trial for their Lyme disease vaccine candidate, VLA15. This trial aims to evaluate the efficacy and safety of the vaccine in individuals aged five years and older living in regions highly endemic for Lyme disease across the United States and Europe.
The VLA15 vaccine is designed to target the outer surface protein of the Borrelia bacteria, which causes Lyme disease. This approach is similar to that of LYMERix, a previous Lyme disease vaccine that was withdrawn from the market 20 years ago. However, VLA15 omits a protein region that some had attributed to adverse events associated with the previous vaccine.
Addressing a Critical Unmet Need
Lyme disease is a growing concern, with cases spreading due to climate change, deforestation, and ecological changes affecting the populations of deer and mice, which carry the disease. Early symptoms of Lyme disease can include fever, headache, and a characteristic circular rash. If left untreated, later symptoms can include joint pain, facial palsy, and inflammation of the brain and spinal cord. While antibiotics are effective in the early stages, some individuals develop persistent symptoms.
Juan Carlos Jaramillo, Valneva's chief medical officer, stated, "Lyme disease continues to spread, representing a high unmet medical need that impacts the lives of many in the Northern Hemisphere."
Trial Design and Potential Timeline
The Phase 3 trial will involve approximately 6,000 participants. Previous trials have indicated that the vaccine candidate provokes a strong immune response in both adults and children, with acceptable safety and tolerability profiles. If the Phase 3 study is successful, Pfizer and Valneva anticipate seeking regulatory authorization in 2025.
Other Preventative Measures
In addition to the VLA15 vaccine, a monoclonal antibody developed by MassBiologics is also in development as a potential preventative measure against Lyme disease. This antibody is currently undergoing human trials.
Public health officials continue to emphasize the importance of checking for ticks after spending time outdoors, especially in areas where Lyme disease is prevalent, as prolonged tick attachment increases the risk of infection.
