PURPOSE AND METHODSThe objective of this multicenter study was to compare the therapeutic index of two different doses of paclitaxel given as a 3-hour infusion in patients with metastatic breast cancer (MBC), who had failed to respond to previous chemotherapy. A total of 471 patients with MBC were randomized to receive intravenous paclitaxel at a dose of 175 or 135 mg/m2 every 3 weeks.RESULTSBetter treatment results were achieved with high-dose (HD) versus low-dose (LD) paclitaxel: overall response rate, 29% versus 22% (P = .108); complete response (CR) rate, 5% versus 2% (P = .088); median time to disease progression, 4.2 versus 3.0 months (P = .027); and median survival time, 11.7 versus 10.5 months (P = .321). Patients previously exposed or resistant to anthracyclines were as likely to respond as those without such prior exposure. Treatment was well tolerated, as documented by the number of administered treatment courses (median, six v five; range, one 17 v one to 18), the low frequency of dose reducti...