"During its first two years of implementation, Project BioShield acquisitions were guided by requirements derived from interagency deliberations in 2003 that involved Cabinet-level Departments and the Executive Office of the President. Under this initial strategy, HHS pursued acquisitions for those highest priority threats for which there were candidate products at relatively advanced stages of development and for which there were opportunities to have a significant impact on improving preparedness. These products included medical countermeasures for anthrax, smallpox, botulinum toxins, and radiological/nuclear agents - the four threat agents initially determined by DHS to pose a material threat to national security. Acquisitions under Project BioShield to date include the currently licensed anthrax vaccine, anthrax therapeutics (monoclonal and human immune globulin), a pediatric formulation of potassium iodide to protect against absorption of radioactive iodine, calcium and zinc diethylenetriaminepentaacetate (DTPA), chelating agents to treat ingestion of certain radiological particles, and botulinum antitoxin". (HHS, HHS PHEMCE Implementation Plan for CBRN Threats, April 2007, p. 3)