title: Investigation of Bioequivalence Between Brand-name and Generic Irinotecan Products.
abstract: To investigate bioequivalence among generic and brand-name irinotecan products.
  
  
  
  Products of Yakult and Daiichi-Sankyo (brand-name products), Sandoz, Nippon Kayaku, Taiho, and Sawai were compared with respect to their composition and antitumor activity.
  
  
  
  High-performance liquid chromatography demonstrated that related substances were within the acceptable range. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay revealed significant differences in cytotoxicity for four cancer cell lines among the products. The concentration of the active compound SN-38 was highest in Yakult's product (23.82 ng/ml) and lowest in Daiichi-Sankyo's product (8.96 ng/ml). MTT assay data were correlated with the SN-38 concentration, suggesting that it influenced differences in cytocidal activity among products. However, the SN-38 concentration was far lower than that of irinotecan (20 mg/ml), suggesting a negligible clinical effect. Metabolism of irinotecan to SN-38 or open-ring forms did not differ significantly among the products.
  
  
  
  The generic products showed equivalent efficacy and safety to the brand-name products.
authors: Department of Pharmacy Services, Saitama Medical Center, Saitama Medical University, Saitama, Japan.|Department of Drug Metabolism and Disposition, Meiji Pharmaceutical University, Kiyose, Japan.
authors: Ken-Ichi
authors: KI
authors: Saito
authors: Department of Drug Metabolism and Disposition, Meiji Pharmaceutical University, Kiyose, Japan.
authors: Yutaka
authors: Y
authors: Inoue
authors: Department of Drug Metabolism and Disposition, Meiji Pharmaceutical University, Kiyose, Japan yoji@my-pharm.ac.jp.
authors: Yoji
authors: Y
authors: Ikegami
authors: Department of Drug Metabolism and Disposition, Meiji Pharmaceutical University, Kiyose, Japan.
authors: Izumi
authors: I
authors: Nanbo
authors: Department of Drug Metabolism and Disposition, Meiji Pharmaceutical University, Kiyose, Japan.
authors: Mari
authors: M
authors: Onozuka
authors: Department of Drug Metabolism and Disposition, Meiji Pharmaceutical University, Kiyose, Japan.
authors: Kazumi
authors: K
authors: Sano
authors: Department of Drug Metabolism and Disposition, Meiji Pharmaceutical University, Kiyose, Japan.
authors: Hisahiro
authors: H
authors: Yoshida
authors: Department of Pharmacy Services, Saitama Medical University International Medical Center, Saitama, Japan.
authors: Toshihiro
authors: T
authors: Sakamoto
authors: Department of Pharmacy Services, Saitama Medical University International Medical Center, Saitama, Japan.
authors: Emi
authors: E
authors: Tatebayashi
authors: Institute of Molecular Oncology, Showa University, Tokyo, Japan.
authors: Ken-Ichi
authors: KI
authors: Fujita
authors: Division of Medical Oncology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan.
authors: Yasutsuna
authors: Y
authors: Sasaki
authors: Department of Pharmacy Services, Saitama Medical University International Medical Center, Saitama, Japan.|Department of Pharmacy Services, Saitama Medical University, Moroyama, Japan.
authors: Takaki
authors: T
authors: Kitazawa
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000493:pharmacokinetics*; D002166:Camptothecin / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D045744:Cell Line, Tumor; D002851:Chromatography, High Pressure Liquid; D016568:Drugs, Generic / Q000493:pharmacokinetics*; D006801:Humans; D000077146:Irinotecan; D013810:Therapeutic Equivalency
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D016568:Drugs, Generic; D000077146:Irinotecan; D002166:Camptothecin
keywords: Cytotoxicity; bioequivalence; chemotherapy; generic; irinotecan