A phase II randomized study comparing navelbine and capecitabine (Navcap) followed either by Navcap or by weekly docetaxel in the first-line treatment of HER-2/neu negative metastatic breast cancer

Abstract

Following the proven efficacy and tolerability of Navcap and Navcap followed by docetaxel in the treatment of MBC, a phase II randomized study was initiated to assess the ORR of both arms in the first-line setting of MBC. Patients with no prior chemotherapy for MBC and HER-2/neu negative were eligible. All patients received Navcap (V 25 mg/m2 on d1 and d8 and C 825 mg/m2 bid D1-14 q3w) for a total of 4 cycles. Patients progressing under Navcap were withdrawn and received docetaxel as second-line treatment. Patients responding or stable were randomized to 2 arms: 4 cycles of Navcap (A) or 12 weekly docetaxel (25 mg/m²/week) (B). From July 2004 to July 2008, a total of 106 patients were enrolled. Ninety-four patients were evaluable before randomization, with a clinical benefit of 58%. Twenty-one patients (22%) had disease progression and were therefore not randomized. Forty-one patients were randomized to arm A and 29 patients to arm B. ORRs were 56 and 71% in arms A and B, respectively. The median time to progression and overall survival were 10 and 35 months in arm A and 12 and 37 months in arm B. Adverse events were mild. Arm A: grade 3-4 neutropenia (10%), grade 3 anemia (5%). Arm B: grade 3 neutropenia (6%), grade 3 anemia (6.2%), and grade 2 alopecia (12%).

Conclusion: Both Navcap and Navcap followed by Docetaxel regimens were tolerated with manageable toxicity, offering consistent activities in terms of response rate for metastatic breast cancer patients.