ROCKVILLE, Md.--(BUSINESS WIRE)--Emergent BioSolutions Inc. (NYSE:EBS) announced today that it has completed a human clinical study that will be used to support expanding the indication for BioThrax® (Anthrax Vaccine Adsorbed) to include post-exposure prophylaxis (PEP) for the treatment of individuals exposed to anthrax. The company has also submitted a final study report for this clinical trial to the Department of Health and Human Services (HHS) which triggers a payment of $8.8 million from HHS under the terms of the $448 million dollar contract announced on September 26th of this year. This clinical trial focused on the immunogenicity of a three-dose BioThrax regimen when used for post-exposure prophylaxis in adults.