Purpose: Between February 1993 and September 1995, 739 patientswith metastatic breast cancer were entered on an Intergrouptrial (E1193) comparing doxorubicin (60 mg/m 2 ), paclitaxel (175mg/m 2 /24 h), and the combination of doxorubicin and paclitaxel(AT, 50 mg/m 2 and 150 mg/m 2 /24 h, plus granulocyte colony-stimulatingfactor 5 mg/kg) as first-line therapy. Patients receiving single-agentdoxorubicin or paclitaxel were crossed over to the other agentat time of progression.
Patients and Methods: Patients were well balanced for on-studycharacteristics.
Results: Responses (complete response and partial response)were seen in 36% of doxorubicin, 34% of paclitaxel, and 47%of AT patients ( P = .84 for doxorubicin v paclitaxel, P = .007for v AT, P = .004 for paclitaxel v AT). Median time to treatmentfailure (TTF) is 5.8, 6.0, and 8.0 months for doxorubicin, paclitaxel,and AT, respectively ( P = .68 for doxorubicin v paclitaxel, P = .003 for doxorubicin v AT, P = .009 for paclitaxel v AT).Median survivals are 18.9 months for patients taking doxorubicin,22.2 months for patients taking paclitaxel, and 22.0 monthsfor patients taking AT ( P = not significant). Responses wereseen in 20% of patients crossing from doxorubicin paclitaxeland 22% of patients crossing from paclitaxel doxorubicin ( P = not significant). Changes in global quality-of-life measurementsfrom on-study to week 16 were similar in all three groups.
Conclusion: (1) doxorubicin and paclitaxel, in the doses usedhere, have equivalent activity; (2) the combination of AT resultsin superior overall response rates and time to TTF; and (3)despite these results, combination therapy with AT did not improveeither survival or quality of life compared to sequential single-agenttherapy.