Emergent BioSolutions Inc.announced that the company has initiated the pivotal immunogenicity and safety study to evaluate a three-dose vaccination schedule of BioThrax (Anthrax Vaccine Adsorbed) for administration to individuals exposed to anthrax.

Through this pivotal, licensure-enabling clinical study, the company seeks to obtain a post-exposure prophylaxis (PEP) indication for BioThrax.

BioThrax is the only FDA-licensed vaccine for the prevention of anthrax infection. It is indicated for the active immunization of adults who are at high risk of exposure to anthrax. BioThrax is manufactured from a culture filtrate, made from a non-virulent strain of Bacillus anthracis.

Approval of the PEP indication would expand use of BioThrax beyond its current pre-exposure prophylaxis indication to add an indication in which the vaccine would be used in combination with antibiotics in people who have potentially been exposed to anthrax spores. Immune protection in this setting is important because of the potential for residual anthrax spores to germinate and cause disease after the currently recommended 60-day course of antibiotic treatment has stopped. BioThrax is the only vaccine licensed by the US Food and Drug Administration (FDA) for the prevention of anthrax disease.

“Emergent is pleased to be working with BARDA to broaden the clinical utility of BioThrax and to further enhance its features in support of the US government's biodefense needs,” said Daniel J Abdun-Nabi, president and chief operating officer of Emergent BioSolutions.

The clinical study involves 200 healthy adult volunteers and will be conducted in four sites within the US. The company anticipates preliminary data to be available in the fourth quarter of 2012.

This study is being funded by contract number HHSO100200700037C, provided by the Biomedical Advanced Research and Development Authority (BARDA) of the Department of Health and Human Services (HHS).

Emergent BioSolutions protects and enhances life by developing and manufacturing vaccines and therapeutics that are supplied to healthcare providers and purchasers for use in preventing and treating disease.