Valneva has shared positive late-stage results for its single-dose chikungunya vaccine in adolescents, which it hopes will support a potential label extension.
Chikungunya is a mosquito-borne viral disease that often causes sudden, large outbreaks with high attack rates, affecting one-third to three-quarters of the population in areas where the virus is circulating.
Infection leads to symptomatic disease in up to 97% of people after three to seven days following the mosquito bite, with clinical symptoms including fever, joint and muscle pain, headache, nausea and rash.
Results showed that a single-dose of VLA1553 generated a high and sustained immune response, with a seroresponse rate of 99.1% 180 days following vaccination compared to 98.8% after 29 days in an immunogenicity subset of adolescents who were chikungunya-negative at baseline.
The day 180 data also confirmed that a single dose of the vaccine was generally safe and well tolerated in adolescents, regardless of previous infection status.
The results come six months after Valneva’s chikungunya vaccine was granted accelerated approval by the US Food and Drug Administration (FDA) for use in individuals ages 18 and older who are at an increased risk of exposure to the disease.
This was supported by clinical trial data showing that the vaccine induced an antibody response rate of 98.9% in adults 28 days after receiving a single dose, with almost all study participants maintaining this response rate six months post-vaccination.
The decision made Ixchiq the first chikungunya vaccine to be licensed anywhere in the world and the company has now outlined that the latest results for the vaccine are “intended to support filing for a potential label extension for use in adolescents aged 12 to 17 years”.
Juan Carlos Jaramillo, Valneva’s chief medical officer, said: “We are highly encouraged by this data, as it reinforces the strong immunity and safety observed in adults and the elderly, upon which FDA approval was granted.
“Given the substantial risk that chikungunya presents to individuals residing in or travelling to endemic regions, it’s imperative to ensure the vaccine is available to all age groups.”