Ex-Rad (or Ex-RAD), also known by the code name ON 01210.Na, or recilisib sodium (INN, USAN) is a drug developed by Onconova Therapeutics and the U.S. Department of Defense.[1][2] This newly developed compound is said to be a potent radiation protection agent. Chemically, it is the sodium salt of 4-carboxystyryl-4-chlorobenzylsulfone.[3]