This is a Phase 2 Multi-Center Clinical Trial (safety and effectiveness trial) in 60 patients (40 denosumab; 20 placebo) who have had a kidney transplant for 12-months or longer with more than 30% of kidney function. The investigators will test whether denosumab safely improves bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) and improves bone strength by high resolution peripheral quantitative computed tomography (HR-pQCT) in the subset of patients recruited at Columbia University Irving Medical Center. These data will inform the development and execution of a larger trial to test if denosumab prevents fractures in kidney transplant recipients.