Background: Osteoporosis is a growing health concern in Australia, significantly contributing to the national disease burden. Osteoanabolic therapies including Teriparatide and Romosozumab have shown improvements in bone mineral density (BMD) and reducing fracture risk in clinical trials, but there is a notable lack of real-world evidence of efficacy, particularly within the Australian context.
Methods: A retrospective cohort study was performed at Royal North Shore Hospital Sydney. All patients prescribed Romosozumab and Teriparatide between 2021 and 2023 were included for analysis if they had completed prescribed treatment and had DEXA BMD scans prior to and post-treatment; n=44 for Romosozumab, n=54 for Teriparatide. A control cohort of patients with T scores <3.0 were also included, n=60.
Results: Romosozumab treatment led to an increase in BMD at the lumbar spine (LS), total hip (TH) and femoral neck, but a decrease at the wrist (p<0.05). Mean BMD gains (±SD) were significantly higher at the LS for romosozumab compared to teriparatide (11.4±8.6% vs 4.97±8.5%, p<0.001) and romosozumab and the control cohort (11.4±8.6% vs 6.6±6.1%, p=0.001). Treatment naïve patients had greater improvements at TH (4.9±1.8%) and LS (14.7±6.6%) compared with patients with previous osteoporosis treatment (TH 1.0±4.7%, p<0.001 and LS 10.6±8.9%, p=0.168). Patients with prior denosumab treatment had smaller gains at the spine (8.1±9.1%) than those without (15.1±6.3%, p=0.005). A moderate negative correlation was observed between length of pre-treatment and BMD gains (r=-0.363, p=0.017).
Conclusion: Romosozumab has demonstrated real-world efficacy in increasing BMD particularly at the spine. A retrospective comparison with Teriparatide has yielded better outcomes compared with Romosozumab. The presence and longer length of previous treatment together appears to reduce the effect of Romosozumab.