A phase II study of three-weekly docetaxel and weekly trastuzumab in HER2-overexpressing advanced breast cancer

To test safety and activity of 3-weekly doses of docetaxel and a weekly dose of trastuzumab in women with HER2-overexpressing advanced breast cancer.

Forty-two women, median age 53 years (range 36-73 years), with HER2-overexpressing advanced breast cancer were enrolled in a study of docetaxel, 75 mg/m(2) q3w for 6 cycles, and trastuzumab, 4 mg/kg loading dose, 2 mg/kg weekly thereafter. Thirty-four patients (81%) had visceral metastatic involvement. Thirty-five patients had received prior chemotherapy as part of their treatment: adjuvant/neoadjuvant (26), metastatic (2) and both (7). Thirty-one patients had been previously exposed to an anthracycline and 11 to paclitaxel. Four patients had previously received high-dose chemotherapy followed by autologous stem cell transplant.

226 cycles (median 6, range 1-6) were administered. The median delivered dose intensity for docetaxel was 24 mg/m(2)/week (range 16-25 mg/m(2)/week). The intent to treat overall response rate was 67% (95% confidence interval, 52-79%). Median progression-free survival, time to treatment failure, and duration of response were 9, 8 and 12 months, respectively. Symptomatic cardiotoxicity (grade 3) occurred in 1 patient. The most common grade 3/4 toxicity was neutropenia (76% of the patients), although febrile neutropenia did not occur.

Three-weekly doses of docetaxel and a weekly dose of trastuzumab is an active and safe combination in patients with HER2-overexpressing advanced breast cancer.