Quadrivalent VLP Vaccine Achieves Phase II Trial Endpoints
- By BSTQ Staff
Novovax Inc.’s quadrivalent seasonal influenza virus-like particle (VLP) vaccine demonstrated the company’s Phase II clinical trial’s primary endpoint of safety and immunogenicity of three ascending dose levels. The VLP vaccine demonstrated immunogenicity against all four viral strains based on Hemagglutination Inhibition Assay (HAI) responses at day 21, was well-tolerated with no vaccine-related serious adverse events observed, and reactogenicity was considered acceptable.
The VLP vaccine also exceeded protocol design expectations by fulfilling the study’s secondary endpoint to fulfill the U.S. Food and Drug Administration (FDA) Center for Biologics Evaluation and Research criteria for accelerated approval. In adult populations under 65 years of age, the VLP vaccine fulfilled the FDA seroprotection criterion at the lower 95 percent confidence bound for all four viral strains included. It also demonstrated the potential to fulfill the FDA seroconversion criterion by demonstrating greater than or equal to 40 percent seroconversion against three of four viral strains. However, despite fulfilling the seroprotection criterion, the fourth virus (B/Brisbane/60/08) failed to meet the seroconversion criterion. But the inclusion of a fourth viral strain in the quadrivalent formulation did not have a significant impact on the immunogenic performance of the other three strains when compared with a trivalent VLP formulation.
An additional secondary endpoint to evaluate the immunogenicity of the VLP vaccine at various dose levels in comparison with a licensed trivalent inactivated vaccine (IIV3) produced in eggs also fulfilled the FDA criteria for seroprotection and seroconversion for each of the included three strains. In general, the comparator IIV3 reached higher levels of HAI than the company’s VLP quadrivalent vaccine.
Additional safety and immune response follow-up is continuing through six months post-treatment.
