The National Institute of Allergy and Infectious Diseases (NIAID) seeks a contractor to advance candidate medical countermeasures (MCMs) for acute radiation syndrome and delayed effects of acute radiation exposure toward FDA approval. The contract will be a single Indefinite Delivery, Indefinite Quantity (IDIQ) type award with a 7-year period of performance beginning on or about July 1, 2027. Task areas include administrative support, animal model development, efficacy testing, non-clinical studies, chemistry/manufacturing/control support, and Phase I clinical studies. Performance location is not specified. No budget amount is provided.