Compstatin (trifluoroacetate salt) (Synonyms: ICVVQDWGHHRCT)

Compstatin is a cyclic peptide inhibitor of complement activation (IC₅₀s = 63 and 12 µM for the classical and alternative pathways, respectively).^1,2 It binds to complement component 3 (C3) and inhibits convertase-mediated cleavage of C3 to the complement activation products C3a and C3b.³ Compstatin (70 µM) inhibits the generation of C3a, activation of polymorphonuclear leukocytes (PMNs), and the binding of PMNs to the polymer surface in an isolated human whole blood model of extracorporeal circulation.⁴ In vivo, compstatin (21 mg/kg) inhibits the generation of C3b, C3c, and iC3b in a baboon model of heparin- and protamine-induced complement activation.⁵

1.Sahu, A., Kay, B.K., and Lambris, J.D.Inhibition of human complement by a C3-binding peptide isolated from a phage-displayed random peptide libraryJ. Immunol.157(2)884-891(1996) 2.Huang, Y.Evolution of compstatin family as therapeutic complement inhibitorsExpert Opin. Drug Discov.13(5)435-444(2018) 3.Ricklin, D., and Lambris, J.D.Compstatin: A complement inhibitor on its way to clinical applicationAdv. Exp. Med. Biol.632273-292(2008) 4.Nilsson, B., Larsson, R., Hong, J., et al.Compstatin inhibits complement and cellular activation in whole blood in two models of extracorporeal circulationBlood92(5)1661-1667(1998) 5.Soulika, A.M., Khan, M.M., Hattori, T., et al.Inhibition of heparin/protamine complex-induced complement activation by Compstatin in baboonsClin. Immunol.96(3)212-221(2000)