T-2513 is a potent and specific inhibitor of topoisomerase I. It acts by forming covalent bonds with the topoisomerase I-DNA complex, thereby enhancing its stability. This interaction disrupts the normal process of DNA replication and RNA synthesis, ultimately resulting in cellular apoptosis.

SN-38 is the metabolite of T-2513[1]. T-2513 has a broad cytotoxicity against a range of human tumor cell lines[2]. Cell Cytotoxicity Assay[2]Cell Line: WiDr, HT-29, SK-BR-3, MKN-1, SK-LU-1, LX-1, KB, and HeLaS3 cells Concentration: 15.1-111.5 ng/mL Incubation Time: 24 hours Result: Exhibited cytotoxicity against a panel of human tumor cell lines with GI 50 s of 32.1, 97.6, 38.6, 15.6, 111.5, 15.1, 34.0, and 50.9 ng/mL for WiDr, HT-29, SK-BR-3, MKN-1, SK-LU-1, LX-1, KB, and HeLaS3 cells, respectively.

T-2513 (1-100 mg/kg) shows Antitumor Activity against Walker-256 carcinoma[2]. Animal Model: Rats bearing Walker-256 carcinoma[2]Dosage: 1, 10, and 100 mg/kg Administration: Result: The ED 50 was 23 mg/kg.