Chrysalis BioTherapeutics won a 3-year, $5.45 million contract from NIH’s National Institute of Allergy and Infectious Diseases (NIAID) to fund continued development of its synthetic thrombin peptide TP508 (rusalatide acetate) as a nuclear countermeasure to prevent tissue damage after exposure to radiation. The firm says the funds will allow it to complete key steps, including additional efficacy validation studies, required for FDA approval. The latest award follows on from previous NIAID grants totaling $6 million for the project, including $3 million awarded in May 2016.
TP508 is the 23-amino-acid stretch of the human thrombin protein. Chrysalis says this stretch of sequence is involved in activation of cell-surface receptors on endothelial cells, inflammatory cells, and progenitor stem cells, which are involved in tissue repair. TP508 effectively activates signaling pathways that prevent cell injury and death after exposure to nuclear radiation and trigger repair and regeneration.
Preclinical studies have shown that administering a TP508 injection 24 hours after exposure to radiation boosts survival by restoring vascular and progenitor cell function. The peptide also helps to speed the repair of DNA damaged by radiation, which the firm suggests might help to prevent delayed effects of radiation, potentially years after exposure. “TP508 represents a natural product released at sites of tissue injury to stimulate repair,” said Dr. Laurie Sower, Chrysalis' vp of research. “It therefore may provide a safe solution to prevent long-term radiation-induced tissue damage.”
Chrysalis is separately developing TP508 for use in patients undergoing radiation therapy for cancer. “We have to be prepared, but hope there is never the need for a nuclear countermeasure,” added Darrell Carney, Ph.D., Chrysalis CEO. “The use of TP508 to protect normal tissue from radiation therapy while allowing radiation to kill tumors, however, could benefit millions of people each year.”