Vaccine company Valneva SE (Nasdaq:VALN) (Euronext Paris:VLA) on Wednesday announced positive Phase 2 results for its Lyme disease vaccine candidate, VLA15.

Data showed a strong anamnestic immune response and a favourable safety profile following a third annual booster dose in children and adults.

The results demonstrated significant antibody responses across all six serotypes, with 100% seroconversion rates reported in all age groups. Safety and tolerability remained consistent with previous boosters, with no concerns raised by the independent Data Monitoring Committee.

VLA15 remains the most advanced Lyme disease vaccine in development, with two Phase 3 trials ongoing. Vaccination in these studies has been completed and, subject to favourable results, Pfizer (NYSE:PFE) aims to file regulatory applications with the US Food and Drug Administration and the European Medicines Agency in 2026.

According to the Centers for Disease Control and Prevention, Lyme disease affects around 476,000 people annually in the United States, with 132,000 reported cases in Europe. VLA15 is being studied in both adults and children across endemic regions in North America and Europe.