Efficacy of once-weekly teriparatide versus alendronate in Chinese postmenopausal osteoporosis: a randomised,...

This randomised controlled trial assessed the effectiveness and safety of weekly 56.5 μg teriparatide (SAL056) compared to alendronate in postmenopausal women in China with osteoporosis at high risk of fractures over 48 weeks.

This phase 3, multicentre, randomised, open-label, active-controlled, parallel-group, non-inferiority trial enrolled postmenopausal women aged 45-80 years with osteoporosis at 37 centres in China. Participants were randomised (1:1) to receive either subcutaneous teriparatide 56.5 μg weekly or 70 mg oral alendronate weekly for 48 weeks, with the primary efficacy assessment at Week 48.

Between November 2021 and September 2023, 493 patients were enrolled (243 in the teriparatide group and 250 in the alendronate group). The primary endpoint, lumbar spine bone mineral density (BMD) at L1-L4, showed a significantly greater increase in the teriparatide group compared to the alendronate group at Week 48 (5.01% vs. 4.20%, mean difference 0.80%, P = 0.025). Sensitivity analysis confirmed these results. At Weeks 24 and 48, teriparatide also resulted in higher hip BMD than alendronate (1.50% vs. 1.46%, P > 0.05 and 3.27% vs. 1.67%, P < 0.001). Procollagen type 1 N-terminal propeptide (P1NP) levels in the teriparatide group increased transiently at Week 12, then declined toward baseline by Weeks 24 and 48, and a decrease in serum cross-linked c-terminal telopeptide of type I collagen (S-CTX) levels from baseline to the end of treatment. Meanwhile, in the alendronate (a typical bone resorption inhibitor) group, CTX level remained continuously suppressed from the baseline. Clinical fracture rates were lower in the teriparatide group than in the alendronate group at Weeks 24 (1.2% vs. 2.8%, P > 0.05) and 48 (1.7% vs. 4.0%, P > 0.05). Teriparatide was generally safe and well tolerated.

Teriparatide (56.5 μg once weekly) was more effective than alendronate in treating postmenopausal osteoporosis with a high fracture risk, significantly increasing L1-L4 BMD over 48 weeks. It was safe, well tolerated, and had a safety profile similar to that of Teribone®.

This study demonstrates that once-weekly teriparatide significantly improves bone mineral density and reduces fracture risk in postmenopausal osteoporosis patients. As a patient-friendly alternative to daily injections, it may enhance adherence and inform clinical guidelines, representing a promising strategy for patients and healthcare systems.