Purpose: We previously demonstrated denosumab (DMAb) increased lumbar spine (LS) and total hip (TH) BMD significantly more than risedronate (RIS) at 12 and 24 months (mos) in glucocorticoid (GC)-treated individuals. Prespecified subgroup analyses of LS BMD at 12 mos indicated that DMAb was superior to RIS across 7 subgroups of GC-treated individuals. This analysis explored the effects of DMAb and RIS on LS BMD in the same subgroups of GC-treated individuals at 24 mos.
Methods: The phase 3, randomized, double-blind, double-dummy, active-controlled study enrolled women and men age ≥18 years receiving ≥7.5 mg prednisone or equivalent daily for <3 mos (GC-initiating [GC-I]) or ≥3 mos (GC-continuing [GC‑C]) before screening. Subjects were randomized 1:1 to DMAb 60 mg SC every 6 mos or RIS 5 mg PO daily for 24 mos. All subjects were to receive daily calcium (≥1000 mg) and vitamin D (≥800 IU). The treatment difference (DMAb – RIS) for percentage change from baseline in LS BMD at 24 mos was estimated in the GC-I and GC-C subpopulations, both overall and in 7 prespecified subgroups.
Results: The study enrolled 795 subjects. Baseline characteristics were balanced between treatment groups within each subpopulation. DMAb was superior to RIS for gains in LS BMD at 24 mos in both the GC-I and GC-C subpopulations. Within each subgroup (Table), DMAb was consistently associated with a greater increase in LS BMD at 24 mos compared with RIS.
Conclusion: DMAb consistently increased LS BMD more than RIS at 24 mos in both GC-I and GC-C subpopulations, with no evidence of directional heterogeneity in treatment effect across 7 prespecified subgroups of GC-treated individuals. DMAb may be a useful addition to the osteoporosis armamentarium in the common clinical setting of GC use.