Chikungunya Vaccine Candidate Met Co-primary Phase 3 Study Endpoints

Bavarian Nordic A/S today announced positive topline results from a Phase 3 clinical trial of its virus-like particle (VLP)-based chikungunya virus vaccine candidate, CHIKV VLP (PXVX0317).

The results up to day 22 post-vaccination showed that CHIKV VLP was highly immunogenic in healthy adolescents and adults, as demonstrated by the strong induction of chikungunya-neutralizing antibodies in 98% of vaccinees in the active group.

The strong neutralizing antibody titres were equal to or exceeded the threshold agreed upon with authorities as a seroprotection marker, meeting the study's primary objectives.

Importantly, CHIKV VLP induced significant neutralizing antibodies in 97% of the subjects at two weeks post vaccination, confirming a rapid onset of protective immunity levels.

These responses were robust and durable, as 86% of the subjects had seroprotective levels of neutralizing antibodies six months post vaccination.

"We are highly encouraged by the positive topline results now demonstrated in both Phase 3 studies of our chikungunya vaccine candidate. Our focus remains to finalize the studies and prepare for regulatory submissions next year," said Paul Chaplin, President and CEO of Bavarian Nordic, in a press release on August 6, 2023.

"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 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."

These results help form the basis for submission of a Biologics License Application to the U.S. Food and Drug Administration and a Marketing Authorization Application to the European Medicines Agency in 2024 to support potential launch of the vaccine in 2025.