Approved Chikungunya Vaccine Shows Sustained 98.3% Sero-Response Rate

Since 2023, the U.S. FDA has approved the Chikungunya virus vaccine, which has been deployed in various countries to curtail outbreaks, with exceptional efficacy data reported by multiple studies.

Adding to this positive trend, Valneva SE today reported further positive Phase 3 clinical trial data in adolescents for its single-shot chikungunya virus vaccine, IXCHIQ®. The vaccine showed a sustained 98.3% sero-response rate one year after a single vaccination.

These results support and strengthen the pivotal data previously reported for adolescents (12 to 17 years old), which supported filing for potential label extensions for this age group in the U.S., Europe, and Canada.

Data from this trial are also expected to support the licensure of IXCHIQ® in Brazil, which would be the first potential approval for use in Chikunguna endemic populations.

Juan Carlos Jaramillo, M.D., Valneva's Chief Medical Officer, commented, “These additional adolescent data confirm IXCHIQ®’s ability to induce a robust, long-lasting antibody response in both younger people and adults with a single vaccination."

"Given the substantial risk that chikungunya presents to individuals residing in or traveling to endemic regions, it’s imperative to ensure the vaccine is available to all age groups and has the potential to offer long-term protection, particularly in low- and middle-income countries where vaccine access is often limited."

"We are now looking forward to the first data in children, which we expect to report imminently.”

Chikungunya outbreaks have been recorded as early as 1824 in India. In 2024, over 425,00 cases and 236 related fatalities were reported in the Region of the Americas.

So far, in 2025, there have been 523 Chikungunya cases in Brazil. 

IXCHIQ® is the only licensed Chikungunya vaccine available at travel clinics and pharmacies in the U.S.