A humanized monoclonal antibody directed against the receptor activator of nuclear factor kappa beta ligand (RANKL) with antiosteoclast activity. Denosumab specifically binds to RANKL and blocks the interaction of RANKL with RANK, a receptor located on osteoclast cell surfaces, resulting in inhibition of osteoclast activity, a decrease in bone resorption, and a potential increase in bone mineral density. RANKL, a protein expressed by osteoblastic cells, plays an important role in osteoclastic differentiation and activation. Check for active clinical trials using this agent. (NCI Thesaurus)