PMX-53

**PMX-53** is a synthetic cyclic hexapeptide and potent, selective antagonist of the complement component 5a receptor 1 (C5aR1, also called CD88), with an IC50 of about 20 nM. It also acts as a low-affinity agonist at the Mas-related G-protein-coupled receptor X2 (MrgX2), which can trigger mast cell degranulation at higher concentrations. PMX-53 is widely used in preclinical studies to investigate complement C5a-related inflammatory and immunological pathways, possessing anti-inflammatory, anti-cancer, and anti-atherosclerotic effects. It has been evaluated for oral bioavailability, but is mainly studied in experimental models for indications such as inflammatory disease, cancer, atherosclerosis, neuropathic pain, and has shown some synergy in combination with immunotherapies. The drug was originally developed by Peptech (later Arana Therapeutics) and also worked on by Cephalon. Its development for clinical indications such as rheumatoid arthritis and osteoarthritis appears to have been discontinued[12][13][11][5][1][3][9][7].

Other names

PMX53PMX-53PMX 533D53