Introduction: Angiogenesis is an established target for the treatment of MBC. Aflibercept (VEGF-Trap) is a humanized fusion protein, which binds VEGF-A, VEGF-B, and PIGF-1 and -2. Patients and Methods: A 2-stage phase II study with primary end points of confirmed tumor response and 6-month progression-free survival (PFS). If either end point was promising after the initial 21 patients, an additional 20 patients would be enrolled. Measurable disease, <2 previous chemotherapy treatments, previous anthracycline or taxane therapy, and Eastern Cooperative Oncology Group performance status of 0 or 1 were required. Aflibercept was given at a dose of 4 mg/kg intravenous every 14 days. Results: Twenty-one patients were enrolled; 71% had visceral disease, 57% were estrogen receptor negative, 19% had HER2+ disease with previous trastuzumab treatment, and 33% had 2 previous chemotherapy regimens. Partial response rate was 4.8% (95% confidence interval [CI], 0.1%-23.8%) and 6-month PFS was 9.5% (95% CI, 1.2%-30.4%). Neither primary end point met efficacy goals and the study was terminated. A median of 3 cycles was given. Median PFS was 2.4 months. Common grade 3 or 4 adverse events were hypertension (33%), fatigue (19%), dyspnea (14%), and headache (14%). Two cases of severe left ventricular dysfunction were noted. Conclusions: Aflibercept did not meet efficacy goals in patients previously treated with MBC. Toxicity was as expected for anti-VEGF therapy.
Bibliographical noteFunding Information:
This study was conducted as a collaborative trial of the NCCTG and Mayo Clinic and was supported in part by Public Health Service grants CA-25224 , CA-37404 , CA-35195 , CA-35101 , CA-35269 , CA-63849 , CA-35113 , and CA-63848 from the National Cancer Institute Department of Health and Human Services . The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Cancer Institute or the National Institutes of Health.
- Breast cancer
- Cooperative group
- Monoclonal antibody