Simmitecan (hydrochloride)

Simmitecan hydrochloride is a potent topoisomerase I (TOP1) inhibitor, which is a 9-substituted lipophilic camptothecin (Camptothecin (HY-16560)) derivative. Simmitecan hydrochloride blocks DNA replication and transcription, thereby inducing tumor cell apoptosis by inhibiting the activity of TOP1. Simmitecan hydrochloride can be used for research on cancers such as liver cancer^[1][2][3]. In Vitro:Simmitecan moderately inhibits the activity of CYP3A4 and weakly inhibits the activity of CYP2D6 in an in vitro recombinant human cytochrome P450 enzyme system, with IC₅₀ values of 8.95 μM and 32.9 μM, respectively^[1]. In Vivo:Simmitecan (3.75-15 mg/kg; intravenous injection; single administration; 24-48 h) exhibits rapid and extensive tissue distribution, conversion to the active metabolite L-2-Z, and predominant biliary excretion in SD rat models^[1].
Simmitecan (15 mg/kg; intravenous injection; single administration; 8 h) exhibits extensive distribution in tissues including tumors and substantial conversion into its active metabolite L-2-Z in nude mouse xenograft models bearing the human hepatocellular carcinoma SMMC-7721 cell line^[1].