Valneva's IXCHIQ Shows Sustained Immune Response in Adolescents and Positive Phase 2 Results in Children
Key Insights
Valneva (search)'s IXCHIQ vaccine demonstrates a sustained 98.3% sero-response rate one year after single vaccination in adolescents, supporting potential label extension.
Phase 2 trial data in children aged 1-11 years shows the vaccine is well-tolerated and highly immunogenic, paving the way for a Phase 3 study.
The UK's MHRA has granted marketing authorization for IXCHIQ, making it available for adults, with plans for label extension applications.
Valneva (search) SE's chikungunya vaccine, IXCHIQ, continues to show promising results in expanding its potential use across different age groups and geographies. Recent data highlights sustained immune responses in adolescents and positive Phase 2 outcomes in children, alongside regulatory approvals and partnerships aimed at broader global access.
Sustained Immune Response in Adolescents
Data from the Phase 3 VLA1553-321 trial demonstrated that a single dose of IXCHIQ induced a robust and sustained immune response in adolescents aged 12 to 17. The study, conducted in Brazil, showed a 98.3% sero-response rate one year after vaccination in participants who were chikungunya virus (search) (CHIKV (search)) negative at baseline. This complements earlier data showing a 99.1% response rate after six months and 98.8% after 28 days. The results support Valneva (search)'s applications for label extension in the U.S., Europe, and Canada, potentially broadening the vaccine's availability to this age group.
According to Juan Carlos Jaramillo M.D., Chief Medical Officer of Valneva (search), "These additional adolescent data confirm IXCHIQ’s ability to induce a robust, long-lasting antibody response in both younger people and adults with a single vaccination."
Positive Phase 2 Results in Children
Valneva (search) also announced positive results from its Phase 2 clinical trial evaluating the safety and immunogenicity of IXCHIQ in 304 children aged one to eleven years. The trial, VLA1553-221, met its primary endpoint, demonstrating that the vaccine was well-tolerated regardless of the dose (half dose or full dose) or previous chikungunya infection. A full dose of the vaccine exhibited a more robust immune response compared to a half dose, leading to the selection of the full dose for the pivotal Phase 3 evaluation in this age group, which the Company expects to initiate in the fourth quarter of 2025.
UK Approval and Global Access
The UK's Medicines and Healthcare products Regulatory Agency (MHRA) has granted marketing authorization for IXCHIQ, making the single-dose vaccine available for adults in the UK. This marks the fourth regulatory approval for IXCHIQ, which is already approved in the U.S., Europe, and Canada for individuals 18 years of age and older. Valneva (search) also plans to submit a label extension application to MHRA to include adolescents aged 12 to 17 years.
Valneva (search) is actively working to expand global access to IXCHIQ through partnerships and grants. A $41.3 million grant from the Coalition for Epidemic Preparedness Innovations (CEPI) and the European Union (EU) will support broader access to the vaccine in low- and middle-income countries (LMICs), including outbreak-affected countries, post-marketing studies, and potential label extensions in children, adolescents, and pregnant women. Additionally, Valneva has signed an exclusive license agreement with the Serum Institute of India (SII) to enable the supply of the vaccine in Asia, with a commitment to priority supply at an affordable price to public health markets in LMICs.
About Chikungunya
Chikungunya is a mosquito-borne viral disease that causes fever, severe joint and muscle pain, headache, nausea, fatigue, and rash. The disease has spread to over 110 countries in Asia, Africa, Europe, and the Americas, with more than 3.7 million cases reported in the Americas between 2013 and 2023. The World Health Organization (WHO) has highlighted chikungunya as a major public health problem, and the medical and economic burden is expected to grow with climate change.