The real-world effectiveness of anti-RANKL antibody denosumab on the clinical fracture prevention in patients with rheumatoid arthritis: The ANSWER cohort study

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by localized and generalized bone loss. The risk of fractures is doubled in patients with RA. Denosumab, an anti-RANKL monoclonal antibody, is used for those with osteoporosis at high risk fracture and it has inhibitory effect of progressive bone erosion in patients with RA. While the increase in bone mineral density by denosumab has been reported in patients with RA, preventive effect of fracture by denosumab remains unknown. This study aimed to evaluate the efficacy of denosumab in treating clinical fracture risk in patients with RA.Patients with RA who received denosumab treatment between 2013 and 2019 were retrospectively evaluated using the ANSWER (Kansai Consortium for the Well-Being of Rheumatic Disease Patients) cohort data. Fracture rates were evaluated between 0 and 6 months (reference period) versus > 6 months (post-reference period) of denosumab use.A total of 873 patients with RA received denosumab, and their characteristics were as follows: 88% females, mean age 68 years, and average disease duration 14.5 years. The hazard rates of all clinical fractures were 0.69 (per 100 person-years) in the reference period and 0.35 in the post-reference period, indicating a 49.2% decrease (p = 0.03).Denosumab suppresses the risk of clinical fractures in patients with RA.