The agency says additional time is needed to decide upon a phase 4 program.
Valeva announced today the FDA moved the company’s PDUFA date for its investigational chikungunya virus(CHIKV) vaccine candidate, VLA1553, from the end of this month to the end of November. The federal agency extended the PDUFA date to allow sufficient time to align and agree on the phase 4 program necessary under the accelerated approval pathway, and no additional clinical data have been requested for the approval process.
“We appreciate and take pride in the fact that our BLA for VLA1553, if approved, will represent the first vaccine candidate to be approved under the accelerated approval pathway in an outbreak disease, and hence the necessary Phase 4 activities will set a future standard,” Valneva CMO Juan Carlos Jaramillo, said in a statement. “We are continuing to work closely and collaboratively with the FDA, and we believe it may be possible to obtain an approval before the new PDUFA date.”
As previously reported by Contagion, VLA1553 met its preliminary endpoint, with 98.9% of participants reaching protective levels of chikungunya virus neutralizing antibodies 1 months after vaccination. The positive results included a 6-month follow-up period, after which 96.3% of participants maintained CHIKV neutralizing antibodies.
The phase 3 clinical trial, VLA1553-301, included 4115 adults 18 years and older. The prospective, double-blind, multicenter, randomized trial commenced in September 2020. Participants received a single dose of lyophilized VLA1553 or placebo, administered as an intramuscular injection.
VLA1553 was also found to be highly immunogenic in study participants 65 years and older, who demonstrated high seroprotection and neutralizing antibody titers comparable to younger participants. Valneva confirmed they will continue monitoring a subset of participants for at least 5 years after VLA1553 vaccination to verify the expected long-term protection of a single injection.
VLA1553 is a live-attenuated, single dose vaccine candidate that received FDA Fast Track and Breakthrough Therapy designations in 2018 and 2021, respectively.