Regulators cite four new serious adverse event reports, halting US distribution while global access efforts continue.
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The US Food and Drug Administration (FDA) has suspended the license for Valneva’s chikungunya vaccine IXCHIQ, effective immediately, after updated safety monitoring identified four new reports of serious adverse events (SAEs) consistent with chikungunya-like illness. The suspension requires Valneva to stop shipping and selling IXCHIQ in the United States, the company announced on August 25, 2025.1
The decision follows the FDA’s earlier August 6 action lifting a temporary pause on use of IXCHIQ in individuals ≥60 years of age, after a prior review of SAEs had concluded the benefits of vaccination outweighed risks in older adults with comorbidities. New VAERS data included four additional SAEs, all reported outside the United States: three cases occurred in adults aged 70–82 years, including one hospitalization with recovery after two days, and one case in a 55-year-old.1
Valneva stated that the clinical presentation of these cases was consistent with events observed in prior clinical trials and post-marketing reports, especially among elderly vaccine recipients, for whom the prescribing information includes warnings and precautions. The company reported IXCHIQ generated €7.5 million in sales during the first half of 2025, out of €91 million total product sales, largely from one-time deliveries to address an outbreak in La Réunion.1
Chief executive officer, Thomas Lingelbach, emphasized that despite the suspension, Valneva remains committed to maintaining vaccine access in countries where IXCHIQ is licensed and to accelerating distribution in low- and middle-income endemic regions. The company is continuing to investigate the new SAE reports and may pursue further regulatory steps under FDA procedures. Valneva is also assessing the potential financial impact of a permanent withdrawal of the US license but has not changed its 2025 revenue guidance.1
FDA suspended IXCHIQ’s US license on August 25, 2025, after four new serious adverse events consistent with chikungunya-like illness were reported.
Cases included three adults aged 70–82 years (one hospitalized, later discharged) and one 55-year-old, all outside the United States.
Valneva is investigating the reports, maintaining sales in other licensed regions, and has not changed its 2025 revenue guidance despite the suspension.
August 7, 2025: Following a three-month safety review in collaboration with the European Medicines Agency, the FDA lifted its pause on IXCHIQ use in adults ≥60 years. Updated labeling added warnings about SAE risks in older adults with chronic conditions. IXCHIQ remained indicated for high-risk adults 18+, while use in low-risk US travelers and immunocompromised individuals was discouraged.2
May 12, 2025: The FDA and CDC recommended pausing IXCHIQ use in adults ≥65 years after reports of SAEs, including one fatality, during a vaccination campaign in La Réunion. The precaution was based on VAERS reports, though no causal link was established.3
April 16, 2025: The Advisory Committee on Immunization Practices (ACIP) recommended chikungunya vaccination for travelers to outbreak regions and laboratory workers at risk. During the meeting, ACIP reviewed safety data from IXCHIQ trials, noting six serious adverse events (SAEs) and highlighting challenges in assessing reactions in older adults with comorbidities.4
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