Phase III Trial of Sunitinib in Combination With Capecitabine Versus Capecitabine Monotherapy for the Treatment of Patients With Pretreated Metastatic Breast Cancer

Purpose Metastatic breast cancer (MBC) remains an incurable illness in the majority of cases, despite major therapeutic advances. This may be related to the ability of breast tumors to induce neoangiogenesis, even in the face of cytotoxic chemotherapy. Sunitinib, an inhibitor of key molecules involved in neoangiogenesis, has an established role in the treatment of metastatic renal cell and other cancers and demonstrated activity in a phase II trial in MBC. We performed a randomized phase III trial comparing sunitinib plus capecitabine (2,000 mg/m2) with single-agent capecitabine (2,500 mg/m2) in patients with heavily pretreated MBC. Patients and Methods Eligibility criteria included MBC, prior therapy with anthracyclines and taxanes, one or two prior chemotherapy regimens for metastatic disease or early relapse after a taxane plus anthracycline adjuvant regimen, and adequate organ function and performance status. The primary end point was progression-free survival, for which the study had 90% power to det...