Immunovaccine announces positive results from immunogenicity study

Immunovaccine Inc., a clinical stage vaccine company, has announced positive results from an immunogenicity study that evaluated anthrax vaccines formulated in the company's DepoVax platform.

This study is part of an ongoing bio-defense research program which was initiated in February 2012 to utilize Immunovaccine's DepoVax adjuvanting technology in advancing the development of next generation vaccines against the most threatening biological agents. Study findings suggested that the DepoVax-based vaccines provided a more long lasting immune response as compared to the licensed anthrax vaccine BioThrax.

The study, which was conducted under the National Institute of Allergy and Infectious Diseases's(NIAID) Preclinical Services Program, was designed to test multiple DepoVax-formulated anthrax vaccines in non human primates, specifically examining immunogenicity and safety after either one or two doses of the vaccine. Study investigators compared the DepoVax-based vaccines to BioThrax, the only commercially available anthrax vaccine. BioThrax requires at least two doses to produce immune responses in animal models.

Preliminary study findings include a single dose of DepoVax-formulated anthrax vaccine produced sustained TNA (toxin-neutralizing antibody) titers detected in six of ten animals starting between day 21 and 49. Animals receiving one dose of Biothrax had no detectable TNA titers.

When a second dose of the DepoVax-formulated vaccine was delivered, there was a significant increase in anthrax TNAs in all immunized animals within one week of the booster administration. Vaccination with the DepoVax-formulated vaccines resulted in no visible injection site reactions. Detailed microscopic examination showed robust immune cell infiltration to the site of vaccination. There was no evidence of systemic or local safety issues.

"Particularly impressive about these findings is the demonstration that DepoVax-formulated vaccines generate toxin neutralizing antibodies with one dose," said Dr Marc Mansour, chief science officer of Immunovaccine. "These findings suggest the potential for DepoVax to enable the development of an effective and safe next generation anthrax vaccine."