Incidence of new fractures in older patients with osteoporosis receiving biosimilar teriparatide or reference products: A retrospective cohort study.

Aims: Biosimilar products have clinical characteristics similar to those of brand-name products and can reduce medical costs. However, the use of biosimilar products for osteoporosis treatments remains limited due to concerns regarding its safety and efficacy. We aimed to clarify the effectiveness and safety of the biosimilar teriparatide compared with those of the reference product using the incidence of new fractures and osteosarcoma as outcomes in osteoporosis patients.

Methods: This study used the DeSC database, which contains medical claims data for various insurers in Japan. We included patients with osteoporosis aged ≥65 years who newly received either biosimilar teriparatide or the reference products between April 2019 and November 2022. Competing risk analyses were performed with adjustments for patient characteristics. The primary and secondary outcomes were the occurrence of new fractures and osteosarcoma, respectively.

Results: Among 45 861 included patients, 3613 and 42 248 were in the biosimilar and reference product groups, respectively. The median follow-up duration was 439 days. New fractures occurred in 6.7% of patients. Cumulative incidence function curves showed similar risks of new fractures over time in both groups. The cause-specific hazard ratio for new fractures was 0.95 (95% confidence interval: 0.82-1.11) for the biosimilar group compared with that of the reference product group. The incidence of osteosarcoma did not differ significantly between the groups (P = .559).

Conclusions: The biosimilar teriparatide showed effectiveness and safety comparable with those of the reference products in treating osteoporosis patients. Our results suggest that clinicians need not hesitate to prescribe biosimilar teriparatide for osteoporosis patients.