Phase II trial with oral idarubicin in advanced breast cancer

Idarubicin, a new analogue of daunorubicin, was administered to 27 patients with advanced breast cancer in a phase II trial. The drug was given orally at a dose of 30-35 mg/m² every 3 weeks. Twenty-two patients were evaluable for response. All evaluable patients were previously treated with one or more chemotherapeutic regimens, including an anthracycline in more than 50% of the cases. Partial remissions were obtained in 5 patients, for a response rate of 23%. The median duration of response was 191 days. Mild nausea and vomiting were common. Diarrhea, which occurred in less than 50% of the patients, was usually short-lived. Alopecia was generally minimal. Myelosuppression was the dose-limiting toxic effect. Leukopenia was frequently seen, with full recovery by day 28 in 81 % of the courses. Thrombocytopenia was less common than leukopenia. Four cases of grade 1 acute cardiac toxicity were recorded. This study suggests that idarubicin can induce regressions in advanced carcinoma of the breast, and justifies further studies in combination with other agents.