NEWTOWN, Pa. & PENNINGTON, N.J.--(BUSINESS WIRE)--Onconova Therapeutics, Inc. today announced positive human safety, tolerability, and pharmacokinetic data from three clinical trials of Ex-RAD (recilisib sodium, ON 01210.Na), a novel radioprotectant being developed as a medical countermeasure for the treatment of acute radiation syndrome (ARS). Ex-RAD and other radioprotection strategies are increasingly important as the threat of accidental and intentional exposure to harmful radiation is becoming a major security concern. These new data were presented on October 3, 2012 at the 58th Annual Radiation Research Society Meeting in San Juan, Puerto Rico.