Comparing Fosamax and Actonel
Direct evaluation of once-weekly Fosamax compared with once-weekly Actonel. Until this study there apparently have been no head-to-head comparisons between Fosamax (alendronate) and Actonel (risedronate). See: J Bone Miner Res. 2005 Jan;20(1):141-51. Epub 2004 Sep 29. Rosen CJ and others, PMID: 15619680. This was a 12-month head-to-head study comparing 70 mg once-weekly alendronate (520 patients) to 35 mg once-weekly risedronate (533 patients) used to treat postmenopausal osteoporosis. End points included bone mineral density (BMD) at six and 12 months of the hip trochanter, total hip, femoral neck and lumbar spine (LS); percent of patients with predefined levels of change in the trochanter and LS BMD at 12 months; and change in biochemical markers of bone turnover at 3, 6 and 12 months. Additionally, tolerability of the medications was evaluated by adverse experience (AE) reporting. Results showed a significantly greater increase in hip trochanter BMD with alendronate at both 12 and 6 months. There were also significantly greater gains in BMD at all BMD sites measured at 12 months. There were significantly greater reductions in all biochemical markers of bone turnover with alendronate compared to risedronate by 3 months. There were no significant differences between groups when comparing upper gastrointestinal (GI) AEs or AEs causing discontinuation. The authors concluded that alendronate ". . . produced greater gains in BMD and greater reductions in markers of bone turnover than risedronate." Editor's comments: This is the first study where you can directly compare the results of using alendronate vs. risedronate since that is the only variable that changed in the study design. Alendronate comes out the clear-cut winner, but risedronate would surely have been statistically superior to placebo. What is interesting is that risedronate has mainly been marketed as superior in preventing upper GI adverse events, yet in this direct comparison there was no statistically significant difference. Since the real bottom line concerning osteoporosis medications is fracture reduction, it would have been educational to include that parameter in the study. Without knowing that, it appears, based upon this study's results, that Fosamax should be the drug of first choice if maximizing improvement in BMD is the goal of treatment and one of the oral once-weekly medications is indicated.