Treatment With Zoledronic Acid Subsequent to Denosumab in Osteoporosis

Denosumab is an antibody against receptor-activator of nuclear factor kappa-B ligand that prevents recruitment and differentiation of mature osteoclasts. Treatment markedly decrease bone resorption and fracture risk, and many patients will reach osteopenic bone mineral density (BMD) levels on treatment with denosumab. The treatment effect on bone turnover and BMD has, however, been demonstrated to be reversible. This study will show if the bone mass can be maintained by administrating zoledronic acid and if timing of the first dose of zoledronic acid after last dose of denosumab matters.