Phase I study of oral vinorelbine and capecitabine in patients with metastatic breast cancer.

Background: To determine the recommended doses of oral vinorelbine (VN) and capecitabine (C) in metastatic breast cancer.

Patients And Methods: Eighteen patients with metastatic breast cancer received oral VN (on days 1 and 8) and C (on days 1 to 14) every three weeks at one of four dose levels: I) 60 mg/m(2) and 1650 mg/m(2)/day; II) 70 mg/m(2) and 1650 mg/m(2)/day; III) 70 mg/m(2) and 2000 mg/m(2)/day; IV) 80 mg/m(2) and 2000 mg/m(2)/day, respectively. The primary endpoint was to determine the recommended doses for the combination of oral VN and C in metastatic breast cancer. Secondary endpoints include evaluating response rate, safety profile and whether or not VN dosage escalation was required.

Results: Severe neutropenia occurred in 28% of patients; and severe anaemia and leucopenia were observed in one patient each (6%). One patient developed febrile neutropenia. Non-hematological toxicities were rare. The response rate was 28% (95% CI: 10-54) in the intention-to-treat population.

Conclusion: The recommended dose is 80 mg/m(2) of oral VN on days 1 and 8, and 2000 mg/m(2)/day of C from days 1 to 14 in three weekly cycles. A phase II study with this schedule is currently under way.