Phase I study of the novel, fully synthetic epothilone sagopilone (ZK-EPO) in patients with solid tumors.

BACKGROUND: Sagopilone (ZK-EPO) is a fully synthetic microtubule-stabilizing agent that has demonstrated high antitumor activity in preclinical models. This first-in-human phase I study aimed to determine the maximum tolerated dose (MTD) and dose-limiting toxic effects (DLTs) of 3-weekly sagopilone treatment. PATIENTS AND METHODS: A total of 52 patients with advanced solid tumors received a 30-min infusion of escalating doses of sagopilone (0.6-29.4 mg/m(2)) every 3 weeks. Nine additional patients were recruited to a 3-h infusion arm (16.53- or 22.0-mg/m(2) dose) to assess the incidence of neuropathy with prolonged infusion. RESULTS: The MTD was established as 22.0 mg/m(2). DLTs comprised peripheral sensory neuropathy (PNP), infection, hyponatremia, diarrhea, and central ataxia. PNP was the most common grade 3 event, with a similar incidence in the 30-min and 3-h arms. Hematologic adverse events were rare and of low intensity. One confirmed partial response (PR) and one unconfirmed PR were reported in the 30-min arm, and a further unconfirmed PR was observed in the 3-h arm. Eleven patients achieved disease stabilization. Sagopilone showed high levels of tissue binding and no obvious serum accumulation in both arms. CONCLUSIONS: These data demonstrate that sagopilone therapy is feasible and well tolerated. The recommended dose for phase II studies is 16.53 mg/m(2), once every 3 weeks.

A phase I/II study of bortezomib and capecitabine in patients with metastatic breast cancer previously treated with taxanes and/or anthracyclines.

BACKGROUND: Proteasome inhibitors are a novel class of compounds entering clinical trials as a method to increase tumour sensitivity to standard chemotherapy. This phase I/II trial was carried out to evaluate the combination of capecitabine and the proteasome inhibitor bortezomib in anthracycline and/or taxane-pretreated patients with metastatic breast cancer. PATIENTS AND METHODS: A total of 35 patients were treated with bortezomib (1.0-1.3 mg/m(2) on days 1, 4, 8 and 11) and capecitabine (1500-2500 mg/m(2) on days 1-14) in 3-week intervals for up to eight cycles. RESULTS: The maximum tolerated doses (MTDs) were bortezomib 1.3 mg/m(2) and capecitabine 2500 mg/m(2). The treatment was generally well tolerated and associated with toxic effects that were consistent with the known side-effects of the individual agents. The intent-to-treat overall response rate was 15% and an additional 27% of patients had stable disease (SD). In the 20 patients treated at the MTD, the response rate was 15% and 40% had SD. Median time to progression and overall survival were 3.5 months [95% confidence interval (CI) 1.9-4.4] and 7.5 months (95% CI 5.6-14.6), respectively. Median duration of response was 4.4 months. CONCLUSION: The combination of bortezomib and capecitabine is well tolerated and has moderate antitumour activity in heavily pretreated patients.