Chrysalin (TP-508)

Chrysalin (TP-508), commonly referred to as rusalatide acetate, is a synthetic 23-amino acid peptide representing the high-affinity receptor-binding domain of human prothrombin (specifically residues 508–530). It is classified as a nonproteolytic thrombin peptide, meaning that while it binds to a distinct subset of thrombin receptors on fibroblasts, endothelial cells, and stem cells, it does not initiate the proteolytic cleavage cascade associated with thrombin’s role in coagulation. TP-508 is not a SARM, not a hormone analogue, and not a dietary supplement. It is not approved by the FDA for human or veterinary use and is intended strictly for laboratory research purposes.