Results of two pivotal Phase 3 studies of the liquid-frozen formulation of Bavarian Nordic A/S’s IMVAMUNE®, supporting a Biologics License Application for U.S. approval of the vaccine, were announced this week. In addition, the company announced results from a Phase 2 study of freeze-dried IMVAMUNE smallpox vaccine, supporting the clinical requirements for an Emergency Use Authorization, which would allow for stockpiling of this version of the vaccine.
The Phase 3 was designed as a randomized, double-blind, placebo-controlled study in 4,000 vaccination-naïve subjects. Three thousand people were vaccinated with three different manufacturing lots of the liquid-frozen IMVAMUNE formulation (1,000 subjects per lot) and compared to 1,000 people who received placebos. “The three lots of IMVAMUNE induced equivalent antibody responses, meeting the primary endpoint of the study, while the favorable safety profile of IMVAMUNE was confirmed in this largest clinical study performed to date,” according to a BioSpace.com article.
No serious adverse cardiac reactions were reported among the 3,000 people vaccinated with IMVAMUNE, confirming the results of a smaller Phase 2 placebo controlled study that was recently published. The safety profile of IMVAMUNE is favorable when compared with traditional smallpox vaccines, such as ACAM2000®, which is approved in the U.S., which have resulted in high rates of cardiac complications in healthy people; 5.73 events per 1,000 immunizations.
The results provide the final clinical data required for approval to start stockpiling the freeze-dried version of IMVAMUNE in the U.S. Strategic National Stockpile. Supported by a contract option of USD $22 million exercised by the Biomedical Advanced Research and Development Authority (BARDA) in 2014, Bavarian Nordic is currently working to transfer the freeze-drying process to a new manufacturing line with a larger commercial capacity. These manufacturing activities remain on track to be finalized this year, notes BioSpace.com.
“Completing this… study is a significant step in the transition to the freeze-dried version of the vaccine, which provides a number of advantages for the future procurement and stockpiling, thereby broadening the commercial potential,” said Paul Chaplin, president & chief executive officer of Bavarian Nordic. “We remain on track to complete the transfer of the manufacturing process, which will enable us to start deliveries in 2016, as we look forward to continuing our successful long-standing collaboration with the U.S. government on its public health preparedness.”