Valneva Shares Positive Phase II Chikungunya Vaccine Data in Children

Valneva has announced promising six-month safety and immunogenicity results from its Phase II trial (VLA1553-221) of the chikungunya vaccine, Ixchiq, in 304 healthy children aged 1–11. The trial, supported by CEPI and the EU, was conducted in Honduras and the Dominican Republic. Children received either a full or half dose of Ixchiq, or an active control (Nimenrix). The full dose showed a stronger immune response at days 15 and 180, with a 96.5% seroresponse rate in CHIKV-naïve participants, and no safety concerns across doses. Results mirrored prior findings in adults and adolescents. Valneva plans to begin a Phase III trial in early 2026 to support label expansion to younger populations. CMO Dr. Juan Carlos Jaramillo emphasized the need for broad vaccine access, citing chikungunya’s threat in endemic areas. This update follows positive Phase II data for Valneva and Pfizer’s Lyme disease vaccine booster, VLA15.

10-06-2025