EPI-X4 is a peptide antagonist of CXCR4 with therapeutic prospects for cancer and inflammatory disorders. (PubMed, Peptides)
Currently, plerixafor (AMD3100) is the only approved CXCR4 antagonist used to mobilize hematopoietic stem cells into the peripheral blood for transplantation therapy...One interesting compound is the endogenous peptide inhibitor for CXCR4 (EPI-X4), recently discovered in the hemofiltrate of dialysis patients. It was traced back to human serum albumin, from where it was generated by the proteolytic activity of cathepsins E and D. Based on its implications for cancer therapy, this review describes its recent evaluations, which include sequence optimization, in vivo efficacy, toxicity, and bioavailability studies.