Radiation countermeasure agents: an update.

IMPORTANCE OF THE FIELD: Ionizing radiation (IR) can produce deleterious effects in living tissues, leading to significant morbidity and a potentially fatal illness affecting various organs dose-dependently. As people may be exposed to IR during cancer radiotherapy or as a result of a radiological/nuclear incident or act of terrorism, the danger of irradiation represents a serious public health problem. At present, however, this problem remains largely impervious to medical management. There is, therefore, a pressing need to develop safe and effective radiation countermeasure (RC) agents to prevent, mitigate or treat the harmful consequences of IR exposure. AREAS COVERED IN THIS REVIEW: Recent advances in the search for RC agents as reflected by the relevant patent literature of the past five years along with peer-reviewed publications are surveyed. WHAT THE READER WILL GAIN: A total of 43 patents, describing approximately 38 chemically diverse compounds with RC potential are analyzed. These include antioxidants capable of scavenging IR-induced free radicals, modulators of cell death signaling or cell cycle progression, cytokines or growth factors promoting tissue repair and inhibitors of inflammatory cytokines. TAKE HOME MESSAGE: Several of these RC candidates appear promising, including at least two that are undergoing evaluation for fast-track clinical development.