Breakthrough Clinical Results
Valneva announced that the FDA has suspended the license for its chikungunya vaccine, IXCHIQ®, due to four new reports of serious adverse events (SAEs) consistent with chikungunya-like illness. The suspension is effective immediately, requiring Valneva to halt shipping and sales in the U.S. The decision follows an earlier FDA action lifting a pause on use in individuals 60 and older. Valneva is investigating the new cases and will consider further steps. While evaluating the financial impact, the company is not altering its revenue guidance. Despite the suspension, Valneva remains committed to providing IXCHIQ® globally to combat chikungunya outbreaks.
Key Highlights
- FDA suspends license for Valneva's chikungunya vaccine IXCHIQ® due to four new serious adverse events.
- Suspension is effective immediately, halting U.S. sales and distribution.
- Valneva is investigating the new cases and will pursue further steps with the FDA.
- Valneva remains committed to providing IXCHIQ® globally to address chikungunya outbreaks.
Incidence and Prevalence
Global Estimates of Chikungunya Incidence and Prevalence
Chikungunya virus (CHIKV) has emerged as a significant global health concern with its distribution primarily concentrated in tropical and subtropical areas. Recent surveillance data shows notable exceptions including the northern coast of the Mediterranean Sea.
Global Distribution Patterns
Countries reporting high recency and frequency of chikungunya cases include India, Brazil, Sudan, and Thailand. Many Latin American and Caribbean countries show high frequency of cases historically, though fewer cases were reported during 2019-2022.
After a 32-year hiatus, CHIKV reemerged in India in 2006, marking the most significant epidemic ever reported. Since 2004, CHIKV has caused major outbreaks worldwide, including the Indian Ocean islands, Asia, and the Americas.
Regional Prevalence Statistics
Africa
- East Africa: Overall pooled prevalence of 20.6% (95% CI: 18.8%-22.5%) based on studies from 2014-2024
- Rwanda and Djibouti: Exceptionally high rates at 63.0% and 50.4% respectively
- Kenya and Somalia: Moderate prevalence of 12.2%
- Ethiopia: Pooled seroprevalence of 24.0%, with highest rates in SNNPR (43.6%) and lowest in Dire Dawa (12.0%)
- Zambia: 36.9% sero-positivity (95% CI 30.5-43.8) in Lukanga swamps
- Sub-Saharan African children: Overall pooled prevalence estimated at 7%
Asia
- Southern Thailand: Among 1466 febrile individuals, 27.1% showed evidence of acute CHIKV infection, with rates highest during epidemic periods (41.1% in 2018-2019 vs 19.3% in 2012-2017)
- Pakistan: A cross-sectional study documented 1549 infected CHIKV patients during the 2016-2018 outbreak
- India: A 2023 study found chikungunya incidence of 24.6% (68/276) among patients with acute undifferentiated febrile illness
- China: In Guangdong province, all 2,132 sera tested in 2012 were negative for CHIKV-IgG antibody, indicating chikungunya was a newly emerging disease in the region
Americas
- Brazil: First local cases recorded in 2014 in Bahia and Amapá states, with demographic patterns showing higher prevalence among females, individuals younger than 60 years, literate individuals, those of non-white race/color and blacks, and urban area residents
Clinical Significance
Chikungunya infections typically present with fever, rash, and severe joint pain. Approximately 40% of cases develop chronic rheumatologic complications persisting for months to years. The disease is frequently misdiagnosed, underreported, and underestimated, particularly in developing nations with limited resources.
Due to its global health impact, CHIKV is now considered a priority pathogen by both CEPI and WHO. With increased urbanization and the emergence of new virus strains showing improved transmission via Aedes albopictus mosquitoes, the at-risk population has greatly increased worldwide.
Economic Burden
Economic Burden of Treating Chikungunya in USA and Europe
Based on current research, there is limited specific information available regarding the latest estimates of the economic burden of treating chikungunya specifically in the USA and Europe.
The most relevant economic data comes from a 2022 study conducted in Brazil, which provides some insight into potential costs. This study reported that in 2017, a large general hospital treated 2,683 chikungunya patients at an estimated cost of $383,514.40. Of this total amount, $174,322.91 (45.5%) was spent on emergency care, while $194,700.59 (50.8%) went toward hospitalizations. The average cost per admission exceeded $2,400 in this Brazilian facility.
The same study documented that 123 hospital professionals contracted chikungunya, resulting in 746 days of absence from work and costs of $14,490.90 due to absenteeism.
Research indicates that reported costs associated with CHIKV diseases are substantial and vary significantly depending on region, age group, and whether healthcare services are delivered through public or private systems. The economic burden of chikungunya can impact the economy in several spheres, with significant effects on both health systems and national economies.
While there have been documented chikungunya cases imported to Europe and North America, as well as outbreaks in Italy (in 2007 and 2017), the available literature does not provide specific economic burden estimates for the USA or European countries. The disease is known to generate absenteeism and cause economic and social losses, but quantitative estimates specifically for these regions are not available in the current research.
The lack of USA and Europe-specific economic data represents a gap in the literature, despite the recognition that chikungunya poses a potential economic threat to healthcare systems worldwide.
Drug used in other indications
IXCHIQ® Clinical Trials Beyond Chikungunya
Based on the available information, there is insufficient data to determine what other indications IXCHIQ® is being trialed for beyond chikungunya virus infection. The context provided does not contain specific information about:
- Additional indications for which IXCHIQ® is currently being investigated
- Clinical trials exploring uses beyond chikungunya prevention
- Intervention models for any such trials
- Study designs for alternative indications
- Treatment protocols for other potential uses
IXCHIQ® (chikungunya virus vaccine, live) received FDA approval specifically for the prevention of disease caused by chikungunya virus in adults 18 years and older who are at increased risk of exposure to chikungunya virus.
Without further information from clinical trial registries, scientific publications, or manufacturer statements, it is not possible to detail any ongoing investigations into alternative uses for this vaccine.
For the most current information about IXCHIQ® clinical trials for indications beyond chikungunya, interested parties should consult:
- ClinicalTrials.gov for registered trials
- Valneva (the manufacturer) official communications
- FDA updates regarding expanded indications
- Peer-reviewed literature for emerging research
Any future trials would likely follow standard vaccine clinical trial designs with appropriate intervention models based on the specific indication being investigated.