‘Severe’ Side Effects: United States Suspends Ixchiq Chikungunya Vaccine

The United States health authorities have suspended the licence for Ixchiq, a vaccine designed to prevent the mosquito-borne chikungunya virus, following reports of severe side effects. The French pharmaceutical manufacturer Valneva disclosed the suspension on Monday, according to a report by the British news agency Reuters.

Ixchiq is one of only two FDA-approved vaccines against chikungunya, a virus that traditionally thrives in tropical and subtropical regions but has, in recent years, spread more widely across the globe.

Valneva, a France-based drug company, received US regulatory approval for Ixchiq in 2023. However, multiple reports of side effects – particularly among elderly patients – have raised concerns. The European Medicines Agency (EMA) had already launched an independent review earlier this year.

According to the company’s statement, the FDA’s suspension order took effect last Friday after four new cases of severe side effects were confirmed. Among the affected patients, three were between the ages of 70 and 82.

Key Facts on Suspension

Valneva’s Chief Executive Thomas Lingelbach stated: “We are considering our next steps, and while the global threat of chikungunya continues to rise, we remain committed to ensuring vaccine availability as an essential public health tool.”

Financial and Market Impact

Valneva has said it is still assessing the financial impact of the suspension, though its income forecast remains unchanged for now. In the first half of this year alone, Ixchiq generated approximately $8.8 million in global sales.

However, the announcement triggered a sharp decline in investor confidence. On Monday morning, Valneva’s shares on the Paris Stock Exchange plummeted by more than 26%.

Public health experts have repeatedly warned that climate change is expanding the range of mosquito populations, increasing the risk of chikungunya outbreaks in new regions.

• Symptoms: The virus presents symptoms similar to dengue and Zika—high fever and severe joint pain. In many cases, symptoms persist, leaving patients debilitated.
• Mortality: Though death is rare, children and elderly patients remain at higher risk.

The World Health Organization (WHO) issued a warning in July that chikungunya could escalate into a major global epidemic unless swift preventive measures are taken.

WHO emphasised that the current situation resembles the early warning signals seen nearly two decades ago, prior to the devastating outbreak in the Indian Ocean region.

Recent Global Outbreaks

The European Centre for Disease Prevention and Control (ECDC) reported that Europe alone has recorded 27 outbreaks of chikungunya this year—the highest figure to date.

Source: Reuters