A Phase II Study of Weekly Nanoparticle Albumin-Bound Paclitaxel With or Without Trastuzumab in Metastatic Breast Cancer

• Published in: Clinical breast cancer 2011-04, Vol.11 (2), p.121-128
• Main Authors: Mirtsching, Barry, Cosgriff, Thomas, Harker, Graydon, Keaton, Mark, Chidiac, Tarek, Min, Myo
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Albumin-Bound Paclitaxel; Albumins - administration & dosage; Albumins - adverse effects; Antibodies, Monoclonal - administration & dosage; Antibodies, Monoclonal - adverse effects; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols - administration & dosage; Antineoplastic Combined Chemotherapy Protocols - adverse effects; Breast Neoplasms - drug therapy; Breast Neoplasms - mortality; Breast Neoplasms - pathology; Carcinoma - drug therapy; Carcinoma - mortality; Carcinoma - pathology; Drug Administration Schedule; Female; Hematology, Oncology and Palliative Medicine; HER2; Humans; Middle Aged; Nab paclitaxel; Nanoparticles - administration & dosage; Nanoparticles - adverse effects; Neoplasm Metastasis; Obstetrics and Gynecology; Paclitaxel - administration & dosage; Paclitaxel - adverse effects; Sensory neuropathy; SPARC; Survival Analysis; Trastuzumab; Veeda Oncology Network
• ISSN: 1526-8209; 1938-0666
• DOI: 10.1016/j.clbc.2011.03.007

Abstract Introduction Weekly administration of nanoparticle albumin-bound ( nab ) paclitaxel as a first-line treatment for metastatic breast cancer (MBC) has not been fully investigated. The addition of trastuzumab, a monoclonal antibody against human epidermal growth factor receptor 2 (HER2), is less understood. This phase II study evaluated the efficacy and safety of weekly nab paclitaxel in the first-line MBC setting. Patients whose tumors overexpressed HER2 also received trastuzumab. Patients and Methods Patients with locally advanced or metastatic breast cancer received nab paclitaxel (125 mg/m2 ) by 30-minute intravenous infusion weekly for 3 of 4 weeks. Patients who were HER2-positive received concurrent trastuzumab. Results Seventy-two patients were enrolled; HER2 expression was detected in 22 patients. The overall response rate (ORR) was 42.2% (95% CI, 30%–55%); 5 patients had a complete response (CR) and 22 patients had a partial response (PR). Additionally, 17 patients experienced stable disease (SD), providing an overall benefit (CR + PR + SD) of 68.8%. Patients with HER2-positive tumors had an ORR of 52.4%; the ORR was 38.1% in the HER2-negative population ( P = .3). Median progression-free survival was 14.5 months (range, 1–49.3 months) and survival rates at 1 year and 2 years were 69% and 62%, respectively. The most commonly observed toxicities were pain (64%), fatigue (58%), sensory neuropathy (54%), infection (46%), nausea (38%), alopecia (33%), and anemia (33%). Conclusion Our findings demonstrate that weekly nab paclitaxel has a favorable safety profile and is well tolerated as a first-line treatment for MBC. An ORR of 42% and an overall benefit of 69% is extremely encouraging, particularly in the HER2-positive population where 52% of patients responded.