Purpose: This phase III trial compared the efficacy and safety of doxorubicin and paclitaxel (AT) to 5-fluorouracil, doxorubicin, and cyclophosphamide (FAC) as first-line therapy for women with metastatic breast cancer.
Patients and methods: A total of 267 women with metastatic breast cancer were randomized to receive either AT (doxorubicin 50 mg/m(2) followed 24 hours later by paclitaxel 220 mg/m(2)) or FAC (5-fluorouracil 500 mg/m(2), doxorubicin 50 mg/m(2), cyclophosphamide 500 mg/m(2)), each administered every 3 weeks for up to eight cycles. Patients had to have measurable disease and an Eastern Cooperative Oncology Group performance status of 0 to 2. Only one prior non-anthracycline, nontaxane-containing adjuvant chemotherapy regimen was allowed.
Results: Overall response rates for patients randomized to AT and FAC were 68% and 55%, respectively (P =.032). Median time to progression and overall survival were significantly longer for AT compared with FAC (time to progression 8.3 months v 6.2 months [P =.034]; overall survival 23.3 months v 18.3 months [P =.013]). Therapy was generally well-tolerated (median of eight cycles delivered in each arm). Grade 3 or 4 neutropenia was more common with AT than with FAC (89% v 65%; P <.001); however, the incidence of fever and infection was low. Grade 3 or 4 arthralgia and myalgia, peripheral neuropathy, and diarrhea were more common with AT, whereas nausea and vomiting were more common with FAC. The incidence of cardiotoxicity was low in both arms.
Conclusion: AT conferred a significant advantage in response rate, time to progression, and overall survival compared with FAC. Treatment was well-tolerated with no unexpected toxicities.