Valneva SE ( VALN ) stock is trading lower on Monday after the U.S. Food and Drug Administration (FDA) suspended the license for Ixchiq, citing four new reports of serious adverse events (SAEs) consistent with chikungunya-like illness.

The license suspension is effective immediately and requires Valneva to stop shipping and selling Ixchiq in the United States.

The suspension follows the FDA’s decision on August 6, 2025, to remove its recommended pause in the use of Ixchiq in individuals 60 years of age and older based on a thorough investigation of reported SAEs, primarily among elderly individuals with multiple underlying health conditions.

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The sudden subsequent decision to suspend Ixchiq is based on updated VAERS data (Vaccine Adverse Event Reporting System), which includes four additional SAEs outside the United States.

Of the four reported cases, three occurred in individuals aged 70 to 82 years, including one hospitalization of an 82-year-old who was discharged after two days. The remaining case occurred in a 55-year-old.

In May, the FDA and the Centers for Disease Control and Prevention (CDC) advised a temporary halt in administering Ixchiq to adults aged 60 and older as they investigate reports of serious adverse events, including neurological and cardiac complications, following vaccination.

Valneva states that all cases describe symptoms consistent with those previously reported during clinical trials and post-marketing experience, particularly among elderly individuals for whom the vaccine’s Prescribing Information (PI) includes warnings and precautions.

The company continues to investigate these cases in detail and, if warranted, will pursue further steps in connection with the FDA’s decision.

Valneva is evaluating the potential financial impact of a permanent withdrawal of the Ixchiq license in the United States, but is not modifying its revenue guidance.

Sales of Ixchiq contributed 7.5 million euros to the company’s total product sales of 91 million euros in the first half of 2025, a significant portion of which resulted from the one-time delivery of vaccine doses to combat the chikungunya outbreak in La Réunion.

Last week, Valneva Health Canada approved the single-dose vaccine, Ixchiq, to prevent disease caused by the chikungunya virus in individuals 12 years and older.

This announcement builds upon the adult marketing authorization already received in Canada and complements the adolescent label extension received in Europe in April 2022.

Price Action: VALN stock is down 20.75% to $9.23 as of the last check on Monday.

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