Bavarian Nordic has shared positive top-line results from a late-stage study of its chikungunya virus vaccine candidate in adults and adolescents.
Chikungunya is a mosquito-borne viral disease for which there is currently no approved vaccine or effective treatment.
Infection leads to symptomatic disease after four to eight days following the bite of an infected mosquito, with clinical symptoms including acute onset of fever, debilitating joint and muscle pain, headache, nausea, rash and chronic arthralgia.
More than 3,200 people aged 12 to 64 years were enrolled and randomised to receive either a single intramuscular injection of Bavarian Nordic’s virus-like particle-based vaccine candidate, CHIKV VLP (PXVX0317), or placebo.
Results showed that the vaccine was highly immunogenic in healthy adolescents and adults at up to 22 days post-vaccination, as demonstrated by the strong induction of chikungunya neutralising antibodies in 98% of those in the active group.
CHIKV VLP induced significant neutralising antibodies in 97% of the subjects at two weeks post vaccination, the company added, confirming a rapid onset of protective levels of immunity. These responses were robust and durable, with 86% of the subjects having seroprotective levels of neutralising antibodies six months post-vaccination.
Bavarian Nordic’s president and chief executive officer, Paul Chaplin, said: “With a fast and durable response, our vaccine has the potential to be the best-in-class to prevent chikungunya infections in adolescents to elderly adults.
“Chikungunya that can often result in a severe and incapacitating disease affects large parts of the world, and with international travel on the rise again, our CHIKV vaccine offers a significant opportunity to address this large unmet medical need.”
Chaplin added that the company’s focus “remains to finalise the studies and prepare for regulatory submissions next year”.
Valneva has its own chikungunya vaccine candidate in late-stage development, VLA1553.
The company reported promising 12-month antibody persistence data for the candidate in December. The trial, VLA1553-303, was set up to confirm the anticipated long-term durability of the antibody response after a single vaccination, following positive immunogenicity and safety data from the phase 3 VLA1553-301 study in March 2022, which demonstrated a seroresponse rate of 96% six months after vaccination.
A Biologic License Application for Valneva’s candidate is currently under priority review by the US Food and Drug Administration, with a Prescription Drug User Fee Act review goal date at the end of this month.