First clinical pharmacokinetic dose-escalation study of sagopilone, a novel, fully synthetic epothilone, in Japanese patients with refractory solid tumors

Purpose Sagopilone has recently been identified and preferentially used for the treatment of taxane-resistant cancer. The purpose of this dose-escalation study was to investigate the safety, tolerability, and pharmacokinetics (PK) of sagopilone in refractory solid tumors. Methods A total of 17 Japanese patients received sagopilone in this Phase I study. Sagopilone was given as a 30-min intravenous infusion once every 3 weeks (one course) with an initial dose of 12.4 mg/m² up to 22.0 mg/m² for a maximum of 6 courses. Results The maximum tolerated dose (MTD) was determined to be 16.5 mg/m². The major dose-limiting toxicity (DLT) was peripheral sensory neuropathy. The PK data demonstrated that sagopilone did not accumulate after repeated administration. Two patients had stable disease (SD) over a period of 12 weeks. Conclusions Our study demonstrated clinically favorable safety, tolerability, and efficacy of sagopilone, which will help define the treatment of advanced tumors in more extensive clinical trials.