Comparison of Denosumab with Romosozumab in the treatment of male osteoporosis: a retrospective cohort study.

We aimed to investigate the efficacy of romosozumab treatment compared with that of denosumab in especially male osteoporosis patients. This retrospective cohort study included 174 Japanese male patients receiving either denosumab or romosozumab for 12 months. Propensity score matching extracted 50 patients per treatment group for standardization of group characteristics. The endpoints include the rate of change in the bone mineral density (BMD) of the lumbar spine, total hip, and femoral neck after 12 months of treatment as well as the changes in serum bone metabolism markers. The mean 12-month percentage increase in the lumbar spine BMD from baseline was significantly greater with romosozumab (13.0% ±1.7%) than with denosumab (4.5%±0.6%) (P < 0.01). The total hip and femoral neck BMD exhibited a similar trend at 12 months; however, no significant between-group differences were observed. With denosumab, bone formation, and resorption marker levels significantly decreased at 6 and 12 months. Conversely, with romosozumab, the levels of bone formation markers increased transiently at 6 months before returning to baseline, whereas bone resorption markers significantly decreased at both time points. Romosozumab demonstrated significantly superior effects over denosumab in improving BMD, especially of the lumbar spine, suggesting that romosozumab can be used for treating male osteoporosis.