Real-world effectiveness of daily teriparatide in Japanese patients with osteoporosis at high risk for fracture: final results from the 24-month Japan Fracture Observational Study (JFOS)

Objective: The Japan Fracture Observational Study (JFOS), a prospective observational study, investigated the real-world effectiveness of daily teriparatide to reduce clinical fracture risk in osteoporotic patients.

Methods: In routine clinical practice, Japanese patients initiated on teriparatide 20 μg/day by subcutaneous injection were enrolled. The primary end-point was the rate of clinical fractures at 6-month intervals over 24 months. Bone mineral density (BMD), procollagen type 1 aminoterminal propeptide (P1NP), back pain, and health-related quality-of-life (HRQoL) information was collected.

Results: Of 1,996 patients at baseline, 90.1% were female, and mean age was 76.9 years. Teriparatide persistence at 12 and 24 months was 68.0% and 51.6%, respectively. Compared to the first 6-month treatment interval, the odds ratio of fractures decreased by 56.4% during 6-12 months, 51.6% during 12-18 months, and 58.8% during 18-24 months (all p < .01). After 24 months, BMD increased by 17.2% (lumbar spine) and 7.9% (total hip). After 6 months, P1NP levels increased by 259.3%. A reduction in back pain (100 mm visual analog scale) of 16.1 mm at 3 months was maintained through 24 months. HRQoL (pain, daily living activities, general health) improved by ≥10% at each post-baseline time point. Of 279 (14.6%) patients with ≥1 adverse event (AE), 71 (3.7%) experienced ≥1 drug-related AE (investigator assessed), including nausea (0.7%), dizziness (0.4%), and decreased appetite (0.3%). Osteosarcoma was not reported; there were no new safety signals.

Conclusions: JFOS demonstrated effectiveness of teriparatide 20 μg/day to reduce the risk of clinical fractures in Japanese patients in a real-world setting.