Randomized Trial of Denosumab in Patients Receiving Adjuvant Aromatase Inhibitors for Nonmetastatic Breast Cancer

Abstract

Purpose Adjuvant aromatase inhibitor therapy is well established in postmenopausal women with hormone receptor–positive breast cancer, but such therapy is complicated by accelerated bone loss and increased fracture risk. We investigated the ability of denosumab, a fully human monoclonal antibody against receptor activator of nuclear factor-κB ligand, to protect against aromatase inhibitor–induced bone loss. Patients and Methods Eligible women with hormone receptor–positive nonmetastatic breast cancer treated with adjuvant aromatase inhibitor therapy were stratified by duration of aromatase inhibitor therapy (≤ 6 v > 6 months), received supplemental calcium and vitamin D, and were randomly assigned to receive placebo (n = 125) or subcutaneous denosumab 60 mg (n = 127) every 6 months. At enrollment, all patients were required to have evidence of low bone mass, excluding osteoporosis. The primary end point was percentage change from baseline at month 12 in lumbar spine bone mineral density (BMD). Results At ...