Phase II study of idarubicin given orally in the treatment of anthracycline-naive advanced breast cancer patients.

A phase II study of 4-demethoxydaunorubicin (idarubicin) administered orally (45 mg/m2) every 3 weeks was conducted in patients with anthracycline-naive advanced breast cancer. Fifty patients were eligible to enter the trial; the median time to disease progression for all 50 patients entered was 22 weeks. Four patients achieved complete response and 14 achieved partial response. Response rate was 36% (complete response + partial response) for all patients entered. The median duration of tumor regression was 39 weeks. The treatment toxic effects observed were both hematologic and nonhematologic and of moderate degrees. Hair loss was observed in 86% of the patients, nausea and vomiting in 96%, and diarrhea in 36%. Cardiac function was monitored with isotope angiocardiography and no patients developed clinical congestive heart failure, up to a median cumulative dose of 260 mg/m2. The left ventricular ejection fraction decreased with a median value of 4% in seven patients treated with greater than 360 mg/m2. This study indicates that idarubicin administered orally has pharmacodynamic effects comparable to those of doxorubicin administered iv on an every-3-week schedule.