A reversible competitive inhibitor of squalene synthase (Ki = 78 pM in vitro); reduces cholesterol synthesis in HepG2 cells (IC50 = 6 µM) and inhibits hepatic cholesterol synthesis in mice (ED50 = 0.2 mg/kg); also inhibits FPTase and GGPTase-I (IC50s = 216 and 50 nM, respectively).