(C-099) Trends in Clinical Prescription Patterns and Selection of Anabolic drugs for postmenopausal women with osteoporosis in Taiwan

Background: Anabolic drugs (including romosozumab, teriparatide and biosimilar of teriparatide) for the treatment of osteoporosis prefer using for advanced osteoporosis patients, meaning bone mineral density(BMD) T-score<-2.5. However, the Taiwan's National Health Insurance (NHI) reimbursed criteria of anabolic drugs are same, but stricter than trials. We hypothesized that, under the same criteria, prescribing decisions may be influenced by drug safety and convenience, particularly due to cardiac safety concerns with romosozumab.

Objectives: To determine drug utilization of anabolic drugs of osteoporosis for postmenopausal women in Taiwan.

Methods: We analyzed data from Chang Gung Research Database (CGRD), the largest multi-institutional electronic medical records collection in Taiwan. We included women aged 55 to 90 years diagnosed with postmenopausal osteoporosis between 2019 and 2024. To ensure a more homogeneous study population, all patients had to meet the criteria of Taiwan NHI reimbursement, including (1) patients with ≥2 fractures (including spine or hip), who are either intolerant to side effects or, despite ≥12 months of anti-resorptive therapy, still experience ≥1 new fracture. (2)BMD T-score of ≤ -3.0. The trend was analyzed annually to evaluate year-to-year variations, considering factors such as age, cardiovascular history, comorbidities, and polypharmacy.

Results: We identified a cohort of 2,979 patients with a mean age of 77.7 (SD: 8.9), all of whom were covered under Taiwan's NHI drug reimbursement. From 2019 to 2020, teriparatide utilization was 100%. However, over the study period, its initiation rate declined by 65% (from 100% to 35.8%; P < 0.001), while romosozumab initiation increased by 60% (from 3% to 48.6%; P < 0.001). A significant crossover in utilization between teriparatide and romosozumab occurred in 2022. Compared to teriparatide users, romosozumab users had a higher prevalence of chronic kidney disease (12.5% vs. 9.9%; P < 0.01) and ischemic heart disease (12.1% vs. 9.7%; P < 0.01). The teriparatide biosimilar was approved in 2022 and introduced into our institution, with its utilization demonstrating a consistent increase over the following two years (0% to 15.5%).

Conclusions: The findings indicate that a history of cardiovascular disease was not a major factor influencing the prescription of romosozumab. The increased romosozumab uses were likely due to clinicians prioritizing adherence over potential side effects. Within the same criteria, the introduction of the biosimilar of teriparatide has significantly impacted market dynamics, reflecting strong acceptance among orthopedic specialists at our institution.