Valneva Reports Positive Phase II Data for Lyme Disease Vaccine VLA15

Valneva has released final safety and immunogenicity results from the Phase II VLA15-221 trial of its Lyme disease vaccine candidate, VLA15, conducted in partnership with Pfizer. The observer-blind, placebo-controlled study included 560 participants, aged five to 17 years for the first time in a Lyme vaccine trial, and evaluated two immunisation schedules (0-2-6 months or 0-6 months).

VLA15, administered intramuscularly as an alum-adjuvanted 180µg dose, elicited robust anamnestic immune responses and demonstrated a favourable safety profile across all age groups. Antibody levels increased after a booster series and remained above baseline six months post the third booster at month 42, with persistence monitored through month 48.

The trial enrolled volunteers in US Lyme-endemic regions, including individuals with and without prior Borrelia burgdorferi exposure. Pending positive Phase III results, Pfizer plans to file regulatory submissions with the FDA and EMA in 2026.

02-12-2025