Randomised phase 3 open-label trial of first-line treatment with gemcitabine in association with docetaxel or paclitaxel in women with metastatic breast cancer: a comparison of different schedules and treatments.

BACKGROUND

This open-label study compared docetaxel/gemcitabine vs. paclitaxel/gemcitabine and a weekly (W) vs. 3-weekly (3 W) schedule in metastatic breast cancer (MBC).

METHODS

Patients relapsed after adjuvant/neoadjuvant anthracycline-containing chemotherapy were randomized to: A) gemcitabine 1000 mg/m2 Day 1,8 + docetaxel 75 mg/m2 Day 1 q3W; B) gemcitabine 1250 mg/m2 Day 1,8 + paclitaxel 175 mg/m2 Day 1 q3W; C) gemcitabine 800 mg/m2 Day 1,8,15 + docetaxel 30 mg/m2 Day 1,8,15 q4W; D) gemcitabine 800 mg/m2 Day 1,15 + paclitaxel 80 mg/m2 Day 1,8,15 q4W. Primary endpoint was time-to-progression (TTP). Secondary endpoints were overall survival (OS) and overall response rate (ORR).

RESULTS

Interim analysis led to accrual interruption (241 patients enrolled of 360 planned). Median TTP (months) was 8.33 (95% CI: 6.19-10.16) with W and 7.51 (95% CI: 5.93-8.33) with 3 W (p=0.319). No differences were observed in median TTP between docetaxel and paclitaxel, with 85.6% and 87.0% of patients progressing, respectively. OS did not differ between regimens/schedules. ORR was comparable between regimens (HR: 0.882; 95% CI: 0.523-1.488; p=0.639), while it was significantly higher in W than in the 3 W (HR: 0.504; 95% CI: 0.299-0.850; p=0.010) schedule. Grade 3/4 toxicities occurred in 69.2% and 71.9% of patients on docetaxel and paclitaxel, and in 65.8% and 75.2% in W and 3 W.

CONCLUSIONS

Both treatment regimens showed similar TTP. W might be associated with a better tumour response compared with 3 W.

TRIAL REGISTRATION

Clinicaltrial.gov ID NCT00236899.