Eighteen previously treated patients with advanced ovarian cancer were entered into a phase 2 trial of chronic low-dose oral etoposide (50 mg/day for 20 days, repeated every 28 days) to determine the activity of this therapeutic strategy in organoplatinum-refractory disease. The treatment program was generally well tolerated, with mild neutropenia the most common side-effect encountered. One patient (6%; 95% confidence interval = 0-17%) achieved a partial response, which lasted for 11 months. Three additional patients (17%), who failed to meet the criteria of a partial response, demonstrated objective evidence of antineoplastic activity. Chronic low-dose oral etoposide administration is associated with definite, although modest, activity in platinum-refractory ovarian cancer.