Treatment Granted Orphan Drug Status for Acute Radiation Syndrome

The Food and Drug Administration (FDA) has granted Orphan Drug designation to TP508 (rusalatide acetate; Chrysalis BioTherapeutics) for the treatment of acute radiation syndrome (ARS). 

ARS, also known as radiation sickness, is an acute illness caused by irradiation of the body due to high levels of nuclear radiation exposure. The illness affects multiple organ systems and often results in death. 

TP508 is a regenerative peptide drug that stimulates repair and revascularization of multiple tissues. It binds to a subset of thrombin receptors that activates signaling pathways to initiate healing cascades on injured tissue. Additionally, TP508 exhibits anti-inflammatory and anti-apoptotic effects on damaged cells and tissues. 

Based on non-clinical and human clinical tissue repair trials, TP508 has shown safety and potential efficacy for the treatment of ARS. Recent studies in murine models have shown TP508 to significantly increase survival after a single injection 24 hours after irradiation. 

The Orphan Drug designation provides the Company 7 years of market exclusivity.

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“This designation represents an important step in our regulatory strategy to establish TP508 to mitigate effects of radiation exposure,” said Dr Darrell Carney, President and CEO of Chrysalis. “The significant effects of TP508 and the FDA and EMA granting of these ODD designations reaffirm our commitment to develop this drug both as a nuclear countermeasure and for use in combination with radiation therapy to mitigate radiation effects on normal tissues.”

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