The cumulative dose of radiation exposure to our astronauts remains one of the limiting roadblocks to longer duration missions in space. Humanetics Corporation (Humanetics) is developing a novel radioprotectant, BIO 300, for use in both clinical radiotherapy and as a radiation countermeasure. BIO 300 is a safe, shelf-stable pharmaceutical which has been shown to mitigate both the acute and delayed effects of radiation exposure. BIO 300 is in advanced stages of clinical development, and is currently being evaluated as a radioprotectant of healthy lung tissue during radiotherapy treatment for non-small cell lung cancer in a Phase I/II trial. One component of developing radioprotectants for space is understanding if the therapy can protect against broad-spectrums of ionizing radiation, rather than just man-made X-Rays. Thus, the objective of this proposal is to examine BIO 300's radioprotective capabilities against mission-relevant doses of neutron/gamma mixed-fields of radiation. Another component of the work proposed here, is to utilize a novel cellular platform of terminally differentiated human cardiomyocytes to investigate degenerative consequences of radiation exposure in a functional human tissue model. Together, these studies will validate the utility of BIO 300 as a countermeasure for extraterrestrial radiation exposures.
