Zolendronate improves bone-densities and micro architectural parameters — A single case study

Abstract

study [1]. When compared with placebo, histomorphometry showed high rates of bone formation and higher trabecular bone volume with no safety issues in the biopsies of patients who were treated with PTH (1–84). However, there is no information on the long-term safety and efficacy of PTH(1–84) treatment in the skeleton. We report the results of the Treatment Extension Study (TRES), which evaluated the effects of 36 months of daily PTH(1–84) treatment. Methods: 99 patients who had completed 18 months of daily placebo treatment together with daily vitamin D3 (400 IU) and calcium (700 mg) in the TOP study and 18 months of daily PTH(1–84) with or without calcium in the Open Label Extension Study (OLES) were enrolled and continued on the same open label regimen for another 18 months in TRES. There were no placebo-treated patients in TRES. The ITT population for TRES comprised 91 patients and there was an interruption in PTH treatment between OLES and TRES of ∼2 months. Evaluable iliac crest biopsies were collected from 14 patients (none of whom had provided a biopsy previously) after 36 months of PTH(1–84) treatment. Results: There were no histopathological abnormalities in cancellous or cortical bone with PTH(1–84) treatment. This included an absence of osteomalacia, marrow fibrosis or dyscrasias, woven bone, abnormal osteoid, or cortical trabecularisation. Cortical porosity was 5.6%, the same as observed at 18 months in TOP. Measures of cancellous, periosteal and endocortical bone formation were similar to those at 18 months. Structural variables, including trabecular bone volume, number, thickness and cortical thickness were generally similar to or slightly lower than corresponding bone biopsies obtained from patients following 18 months of PTH therapy. Conclusion: Daily treatment of postmenopausal osteoporotic women with PTH(1–84) for 36 months was generally safe and biopsies showed that cancellous and cortical bone appeared entirely normal. The consistency of the biopsy results following 18 and 36 months of PTH treatment suggests that long-term therapy with PTH preserves the initial benefits accrued during initial exposure. 1. Recker RR, et al. Bone 2009;44:113-9. Conflict of interest: None declared.