A phase I study of UFT-oral vinorelbine in metastatic breast cancer

Despite current treatment options, metastatic breast cancer (MBC) remains essentially incurable, requiring research on new drugs or combinations to improve survival and quality of life.

This phase I study was designed to define the maximum-tolerated dose (MTD), dose-limiting toxicity (DLT) and recommended dose of all-oral tegafur-uracil (UFT)/folinic acid combined with vinorelbine as chemotherapy for MBC. Starting doses were 40 mg/m(2)/week of oral vinorelbine administered continuously and 250 mg/m(2)/day of UFT plus 90 mg/day of folinic acid from day 1 to day 28, followed by a 1-week rest period.

Ten patients were included. Eight were evaluable for toxicity and antitumor response. The second dose level was shown to be the MTD. At this dose, 2 out of 5 patients receiving oral vinorelbine at 40 mg/m(2)/week and UFT at 300 mg/m(2)/day developed DLT consisting of grade 3 asthenia and grade 3 nausea despite standard prophylaxis. Other toxicities were grade 1 diarrhea and anemia. There were no treatment-related deaths.

The recommended dose for this combination seems to be the first dose level. A stable response was observed for 6 patients (average 33 weeks). This combination appears to be well-tolerated and offers an alternative to intravenous chemotherapy.