In a phase II trial, 29 patients with anthracycline-pretreated or anthracycline-resistant metastatic breast cancer in whom anthracycline-containing first- or second-line chemotherapy failed received combination paclitaxel (Taxol)/gemcitabine (Gemzar). The initial regimen of paclitaxel at 175 mg/m2 on day 1 and gemcitabine at 1,000 mg/m2 on days 1, 8, and 15 of a 28-day cycle was given to five patients for a total of 27 cycles. The regimen resulted in excessive thrombocytopenia and was subsequently changed to gemcitabine at the same dose on days 1 and 8 of a 21-day cycle, with study treatment being given for a maximum of eight cycles. This regimen was well tolerated. Further evaluation of this regimen in minimally and heavily pretreated patients with advanced breast cancer is warranted.