US halts Chikungunya vaccine distribution due to significant adverse reactions reported
The United States Food and Drug Administration (FDA) has suspended the approval of the Chikungunya vaccine Ixchiq, manufactured by French pharmaceutical company Valneva, following four additional reports of serious side effects. The suspension, which took effect immediately, was announced on August 25, 2025.
The FDA's decision comes after reports of side effects, particularly in older patients. Three of the four new cases involved individuals aged 70 to 82. The European Medicines Agency conducted a review of the Ixchiq vaccine's use in older patients earlier this year.
Valneva, the company that produces the Ixchiq vaccine, remains committed to maintaining access to the vaccine as a global health tool. However, the suspension has not prompted any modifications to the company's revenue guidance at this time.
The Ixchiq vaccine for the chikungunya virus, which primarily occurs in tropical and subtropical regions but has recently been discovered worldwide, generated sales of 7.5 million euros (US$8.8 million) in the first half of this year. It is one of two vaccines approved by the FDA for the chikungunya virus.
Valneva obtained US approval for the Ixchiq vaccine in 2023, marking a significant milestone for the company. The chikungunya virus continues to escalate globally, making the vaccine's suspension a concerning development.
CEO of Valneva, Thomas Lingelbach, has stated that the company is evaluating the financial impact of the suspension of the Ixchiq vaccine's licence. The FDA's action underscores the importance of continued vigilance in monitoring the safety of vaccines.
As the situation develops, Valneva and the FDA will provide updates on the status of the Ixchiq vaccine. In the meantime, public health officials continue to emphasise the importance of mosquito control and personal protective measures to prevent the spread of the chikungunya virus.
