Valneva Reports Positive 6-Month Pediatric Data For Chikungunya Vaccine IXCHIQ®

Valneva SE announced promising six-month data from its Phase 2 trial evaluating the safety and immune response of its single-dose chikungunya vaccine, IXCHIQ®, in children aged one to eleven years. The study, partially funded by CEPI with support from the European Union, included 304 pediatric participants and compared two dosage levels. The findings are expected to support a pivotal Phase 3 trial scheduled for early 2026 to extend the vaccine’s approved use to children.

Juan Carlos Jaramillo, M.D., Chief Medical Officer of Valneva, said, “The six-month persistence and safety data in children are aligned with the robust antibody response and safety profile we reported in adolescents after a single vaccination. Considering the significant risk chikungunya poses to individuals living in or traveling to endemic areas, it’s crucial to ensure that the vaccine is accessible to people of all ages and capable of potentially offering long-term protection from a single shot. This is especially important in Low- and Middle-Income countries (LMICs) where access to vaccines is often limited.”

The data showed that the full-dose formulation of IXCHIQ® generated a stronger and longer-lasting immune response than the half-dose, with a 96.5% seroresponse rate in chikungunya virus-naïve children at Day 180 post-vaccination. These immune response levels were consistent with those previously observed in adult and adolescent trials. Both dose levels demonstrated good tolerability, with no safety concerns reported across the pediatric age group, regardless of prior infection status.

This trial supports the full dose of IXCHIQ® in future pediatric studies. Rising cases of chikungunya worldwide, such as over one million in Brazil from 2019 to 2024 and continued outbreaks in Maharashtra and Telangana in India, show how necessary pediatric protection becomes. With ongoing outbreaks in the French islands of La Réunion and Mayotte, the Centers for Disease Control and Prevention warns there is a clear need for a vaccine that can be used to immunize children against chikungunya disease.