Multicentre trial of weekly risedronate on bone density in adults with cystic fibrosis

Abstract Background The aim of this study was to assess the efficacy, tolerability and safety of risedronate in adults with CF. Methods Patients with a lumbar spine (LS), total hip (TH) or femoral neck (FN) bone mineral density (BMD) Z-score of − 1 or less were randomised to receive risedronate 35 mg weekly or placebo, and calcium (1 g) + vitamin D3 (800 IU). Results At baseline, BMD Z-scores in the risedronate (n = 17) and placebo (n = 19) groups were similar. By 24 months, 7/17 risedronate patients vs 0/19 placebo patients stopped the study medication due to bone pain. After 24 months treatment, the mean difference (95% CI) in change in LS, TH and FN BMD between the risedronate vs placebo groups was 4.3% (0.4, 8.2) p = 0.03; 4.0% (− 0.5, 8.6) p = 0.08; and 2.4% (-3.5, 8.2) p = 0.41. Conclusions After two years treatment there was a significant increase in LS BMD with weekly risedronate compared to placebo.