Phase II study of pegylated liposomal doxorubicin in combination with gemcitabine in patients with metastatic breast cancer

Purpose: We conducted a phase II clinical trial to determine the clinical efficacy and safety of pegylated liposomal doxorubicin in combination with gemcitabine in patients with metastatic breast cancer. Patients and Methods: Patients were eligible if they had measurable disease, no prior chemotherapy for metastatic disease, and a performance status ≤ 2 on the Zubrod scale. Patients received pegylated liposomal doxorubicin 24 mg/m² intravenously on day 1, plus gemcitabine 800 mg/m² intravenously on days 1 and 8 of each 21-day cycle. Results: Of 49 patients enrolled, 27 had received prior adjuvant chemotherapy (19 with an anthracycline). Prior median cumulative anthracycline dose was 240 mg/m². In total, three complete responses and 21 partial responses were achieved in 46 assessable patients, for an overall response rate of 52% (95% confidence interval, 37% to 67%). Responses were observed in 11 (58%) of 19 patients with previous anthracycline exposure. Median response duration was 5.6 months, time to progression was 4.5 months, and overall survival was 16.1 months. Although the most common grade 3 to 4 toxicities were hematologic, few neutropenic complications resulted. The most frequent nonhematologic toxicities were nausea and vomiting, fatigue, stomatitis, and hand-foot syndrome. One patient previously treated with an anthracycline developed a transient decrease (21%) in the left ventricular ejection fraction, with cardiac function recovering within 2 months. Conclusion: Pegylated liposomal doxorubicin in combination with gemcitabine is active and well tolerated in patients with metastatic breast cancer. Median overall survival was 16.1 months, and approximately 78% of patients derived clinical benefit from treatment. This regimen represents a therapeutic option for patients receiving front-line therapy for their metastatic breast cancer.