ObjectivesTo assess cost implications per patient, per year, and to predict the potential annual budget impact when patients with bone metastases secondary to solid tumours at risk of skeletal-related events (SREs) transition from zoledronic acid (ZA; 4 mg every 3–4 weeks) to denosumab (120 mg every 4 weeks) in Austria, Sweden and Switzerland.MethodsCountry specific costs for medication and administration, patient management and SREs (defined as pathologic fracture, radiation to bone, surgery to bone and spinal cord compression) were assessed over a 1-year time horizon. Drug administration and patient management costs were taken from available public sources. SRE costs were based on local unit costs applied to country specific healthcare resources obtained from a multinational retrospective chart review study. Due to lack of real world data for the included countries, SRE rates were derived from phase III clinical trials in patients with advanced cancer and bone metastases. These trials demonstrated that denosumab was superior to ZA in the reduction of SREs.ResultsEstimated total annual cost savings for each patient transitioned from ZA to denosumab varied by country and cancer type, ranging from €1583 to €2375 in Austria, from €1980 to €2319 in Sweden (9.1 SEK/€) and from €3408 to €3857 in Switzerland (1.2 CHF/€). Cost savings were mainly driven by the lower SRE related costs and lower administration costs of denosumab compared with ZA.ConclusionsDenosumab offers superior efficacy compared with ZA in patients with solid tumours and bone metastases. Cost savings are predicted in the Austrian, Swedish and Swiss healthcare systems following treatment transition from ZA to denosumab.