CP-609754 shows selective inhibition of farnesyltransferase.
CP-609754 inhibits farnesylation (IC50 = 1.72 ng/mL) of mutant H-Ras in 3T3 H-ras (61L)-transfected cell lines. CP-609754 selectively inhibits farnesylation of both H- and K-Ras proteins in 3T3 transfectants. CP-609754 is competitive for the prenyl acceptor (H-Ras protein) and noncompetitive for the prenyl donor farnesyl PPI. CP-609754 interacts with the farnesyltransferase-farnesyl PPI complex and competes for the binding of the Ras protein[1].
CP-609754 has in vivo antitumor activity against 3T3 H-ras (61L) tumors. With twice daily oral dosing of CP-609754, tumor regression is achieved with a dose of 100 mg/kg; the ED50 for tumor growth inhibition is 28 mg/kg. With continuous i.p. infusion of CP-609754, tumor growth is inhibited by >50%, and tumor farnesyltransferase activity inhibited by >30% in mice in which the plasma concentration of CP-609754 is maintained above 118 ng/mL[1].