Emergent BioSolutions Advances Program Supporting Licensure of a Post-Exposure Prophylaxis Indication for BioThrax

Emergent BioSolutions Inc. (NYSE: EBS) today announced that its pivotal Phase 3 clinical study evaluating the immunogenicity and safety of a three-dose BioThrax^® (Anthrax Vaccine Adsorbed) regimen for post-exposure prophylaxis (PEP) has been completed and has met its primary and key secondary endpoints. The company has submitted the final clinical study report to the Biomedical Advanced Research and Development Authority (BARDA) and the U.S. Food and Drug Administration (FDA) and these results will be used to support an eventual supplemental Biologics License Application (sBLA) seeking licensure of a PEP indication for BioThrax. BioThrax is the only FDA-licensed vaccine for the prevention of anthrax disease. BioThrax is not licensed for use in a post-exposure setting.

“Emergent’s on-time completion of this study and submission of our clinical study report represents a key milestone in our BioThrax PEP development program,” said Adam Havey, executive vice president and president of Emergent’s biodefense division. “These data represent the culmination of a multi-year effort aimed at evaluating the use of BioThrax for PEP. This work is an excellent example of the partnership between industry and the U.S. Government agencies including BARDA, FDA, the National Institute of Allergy and Infectious Diseases, and the Centers for Disease Control and Prevention.”

The Phase 3 open-label clinical study enrolled 200 healthy adult volunteers and was conducted at four sites within the U.S. Data from this study will be presented at the International Conference on Bacillus anthracis, B. cereus, and B. thuringiensis (Bacillus ACT) in September 2013. This study is fully funded under contract number HHSO100200700037C provided by BARDA within the Office of the Assistant Secretary for Preparedness and Response in the U.S. Department of Health and Human Services.

Additionally, data from non-clinical and clinical PEP studies that preceded the Phase 3 study have been published in the July issue of Clinical and Vaccine Immunology. The publication describes pre-exposure and post-exposure vaccine efficacy study data in animal models of anthrax disease, as well as exploratory clinical vaccine immunogenicity study data. This is the first comprehensive report of animal and clinical studies evaluating efficacy and immunogenicity of a vaccine that will utilize the FDA “Animal Rule” as a pathway to licensure by demonstrating efficacy in adequate and well-controlled animal models.

About BioThrax

BioThrax is the only FDA-licensed vaccine for the prevention of anthrax disease. It is indicated for the active immunization of adults who are at high risk of exposure to anthrax. BioThrax is not licensed for use in a post-exposure setting. The safety and efficacy of BioThrax have not been established in pediatric or geriatric populations. Individuals are not considered protected until they have completed the three-dose primary immunization series. Vaccination with BioThrax may not protect all individuals.

BioThrax is manufactured from a culture filtrate, made from a non-virulent strain of Bacillus anthracis. To date, Emergent has delivered over 66 million doses of BioThrax to the U.S. government and continues to deliver additional doses under active procurement contracts. Since 1998, over 11 million doses have been administered to more than 2.9 million military personnel. For full prescribing information, please visit http://www.biothrax.com/prescribinginformation_biothrax_us.pdf.

BioThrax^® (Anthrax Vaccine Adsorbed) and any and all Emergent BioSolutions Inc. brand, product, service and feature names, logos and slogans are trademarks or registered trademarks of Emergent BioSolutions Inc. or its subsidiaries in the United States or other countries. All rights reserved.

About Emergent BioSolutions

Emergent BioSolutions is a specialty pharmaceutical company seeking to protect and enhance life by offering specialized products to healthcare providers and governments to address medical needs and emerging health threats. Additional information may be found at www.emergentbiosolutions.com. Follow us on twitter: @emergentbiosolu.

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