Phase II to III Study Comparing Doxorubicin and Docetaxel with Fluorouracil, Doxorubicin, and Cyclophosphamide As First-line Chemotherapy in Patients with Metastatic Breast Cancer: Results of a Dutch Community Setting Trial for the Clinical Trial...

Purpose: To compare the efficacy and safety of doxorubicin and docetaxel (AT) with fluorouracil, doxorubicin, and cyclophosphamide (FAC) as first-line chemotherapy for metastatic breast cancer (MBC).

Patients And Methods: Patients (n = 216) were randomly assigned to either AT (doxorubicin 50 mg/m(2) and docetaxel 75 mg/m2) or FAC (fluorouracil 500 mg/m2, doxorubicin 50 mg/m2, and cyclophosphamide 500 mg/m2); both regimens were administered on day 1, every 3 weeks.

Results: A median number of six cycles was delivered in both arms, with a median relative dose-intensity of more than 98%. Median time to progression (TTP) and median overall survival (OS) were significantly longer for patients on AT compared with FAC (TTP: 8.0 v 6.6 months, respectively; P = .004; and OS: 22.6 v 16.2 months, respectively; P = .019). The overall response rate (ORR) was significantly higher in patients on AT compared with FAC (58% v 37%, respectively; P = .003). The ORR on AT was also higher in patients with visceral disease compared with FAC patients with visceral disease (59% v 36%, respectively; P = .003). There were no differences in grade 3 to 4 neutropenia and infections (AT 89% v FAC 84% and AT 12% v FAC 9%, respectively). Neutropenic fever was more common in AT-treated patients than FAC-treated patients (33% v 9%, respectively; P < .001). Grade 3 to 4 nonhematologic toxicity was infrequent in both arms. Congestive heart failure was observed in 3% and 6% of patients on AT and FAC, respectively.

Conclusion: In this phase II to III study, AT resulted in a significantly longer TTP and OS and a higher objective ORR than FAC. First-line AT is a valid treatment option for patients with MBC.