摘要
Xinze (R) is a new capsule formulation of topotecan being made in China which is similar to Hycamtin (R), the currently available oral formulation approved in 2007 for the treatment of relapsed small cell lung cancer (SCLC). As topotecan bioavailability and pharmacokinetic data for Chinese patients is limited, the aim of the study was to assess the absolute bioavailability and pharmacokinetics of Xinze (R) in Chinese patients with SCLC treated intravenously (i.v.) with 1.5 mg/m(2)/d topotecan (Hycamtin (R)) on day 1 and treated orally with 1.5 mg/m(2)/d topotecan on day 2. An ultra high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for the determination of total topotecan (lactone and carboxylate forms) and of topotecan in the lactone form in human plasma samples. The method was validated with respect to selectivity, extraction recovery, matrix effect, linearity, intra- and inter-day precision, accuracy, and stability. The quantification limits were 0.5 ng/mL for total topotecan and 0.1 ng/mL for topotecan in the lactone form. The mean absolute bioavailability of total topotecan and topotecan in the lactone form was 42.24 +/- 12.9% and 47.18 +/- 16.9%, respectively, values which illustrate good systemic exposure. The presented results demonstrated this method can be a sensitive and efficient tool for bioavailability studies of topotecan.
- 出版日期2013-3-25
- 单位中国医学科学院北京协和医院; 中国医学科学院肿瘤医院