Chikungunya Vaccine Candidate Found Safe in Adolescents

Valneva SE today reported positive initial Phase 3 safety data in adolescents for its single-dose chikungunya virus (CHIKV) vaccine candidate VLA1553.

On August 28, 2023, Valneva announced the initial safety data generated in the ongoing trial VLA1553-321, Valneva's first clinical trial in an endemic area (Brazil) and with individuals previously infected with CHIKV, showed that VLA1553 was generally safe and well tolerated in adolescents aged 12 to 17 years, regardless of previous CHIKV infection.

In this study, 754 individuals were vaccinated in trial VLA1553-321, and the present analysis includes safety data up to Day 29. An independent DSMB has continuously evaluated safety data during the trial and identified no safety concerns.

Overall, the adverse event profile is consistent with the profile observed in Valneva's pivotal Phase 3 trial in adults, reported in March 2022.

Immunogenicity data for this new trial are expected in November 2023.

Juan Carlos Jaramillo, M.D., Chief Medical Officer of Valneva, commented in a press release, "These new safety data in a younger population and individuals previously infected with the chikungunya virus confirm the safety profile we previously observed in adults and the elderly."

"Chikungunya represents a major threat for people traveling to or living in areas where chikungunya virus is endemic, it is, therefore, our objective to make this vaccine available to all age groups, especially as no vaccine or specific treatments are currently available for this debilitating disease."

Funded by the Coalition for Epidemic Preparedness Innovations and conducted in collaboration with Brazil's Instituto Butantan, the VLA1553-321 adolescent trial is intended to support label extension in this age group following a potential initial regulatory approval in adults from the U.S. Food and Drug Administration. The trial is also expected to support the vaccine's licensure in Brazil, which would be the first potential approval for use in endemic populations.

The present safety analysis will also enable regulatory submission to the European Medicines Agency in 2023.

If licensed, this would be the first CHIKV vaccine candidate approved.