Phase I Study of Pazopanib in Combination with Weekly Paclitaxel in Patients with Advanced Solid Tumors

作者:Tan Antoinette R*; Dowlati Afshin; Jones Suzanne F; Infante Jeffrey R; Nishioka Jennifer; Fang Lei; Hodge Jeffrey P; Gainer Shelby D; Arumugham Thangam; Suttle A Benjamin; Dar Mohammed M; Lager Joanne J; Burris Howard A III
来源:Oncologist, 2010, 15(12): 1253-1261.
DOI:10.1634/theoncologist.2010-0095

摘要

Purpose. To evaluate the maximum tolerated regimen (MTR), dose-limiting toxicities, and pharmacokinetics of pazopanib, an oral small-molecule tyrosine kinase inhibitor of vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit, in combination with paclitaxel.
Patients and Methods. Pazopanib was given daily with weekly paclitaxel on days 1, 8, and 15 every 28 days. Dose levels of pazopanib (mg/day)/paclitaxel (mg/m(2)) were 400/15, 800/15, 800/50, and 800/80. An expanded cohort was enrolled at the MTR. Plasma samples were collected to evaluate the effect of pazopanib, an inhibitor of cytochrome P450 (CYP)3A4, on the pharmacokinetics of paclitaxel, a CYP3A4 and CYP2C8 substrate.
Results. Of 26 enrolled patients, 17 were treated at the MTR of 800 mg pazopanib and 80 mg/m(2) paclitaxel. Dose-limiting toxicities included a grade 3 abscess and grade 2 hyperbilirubinemia. Other toxicities included elevated liver transaminases and diarrhea. Six patients (23%) had partial responses and 15 patients (58%) had stable disease. Administration of 800 mg pazopanib resulted in a 14% lower paclitaxel clearance and a 31% higher paclitaxel maximal concentration than with administration of paclitaxel alone at 15, 50, and 80 mg/m(2). At the MTR, coadministration of 800 mg pazopanib and 80 mg/m(2) paclitaxel resulted in a 26% higher geometric mean paclitaxel area under the curve.
Conclusion. Pazopanib, at a dose of 800 mg daily, can be safely combined with a therapeutic dose of paclitaxel at 80 mg/m(2) when administered on days 1, 8, and 15, every 28 days. The observed greater plasma concentra-tions of paclitaxel given concurrently with pazopanib suggest that pazopanib is a weak inhibitor of CYP3A4 and CYP2C8. The Oncologist 2010;15:1253-1261

  • 出版日期2010-12