CONTEXT

Wnt/β-catenin signaling pathway is one of the pathogenic mechanisms of glucocorticoid-induced osteoporosis (GIOP). We previously reported the potential of inhibiting sclerostin as a treatment for GIOP.

OBJECTIVE

To compare the efficacy of romosozumab (ROMO), a monoclonal antibody against sclerostin, with existing therapy for GIOP.

METHODS

Patients with rheumatic diseases who had not previously received treatment for osteoporosis and were newly treated with prednisolone 15 mg/day or more were randomly assigned to receive ROMO, denosumab (DMAb), or bisphosphonates (BP). After the initiation of glucocorticoid therapy, we measured the bone mineral density (BMD) of the lumbar spine, femoral neck, and total hip every 6 months and bone turnover markers every 3 months for 12 months.

RESULTS

Eleven patients were assigned to the ROMO group, 14 to the DMAb group, and 14 to the BP group. The median [25th to 75th percentile] percent change in lumbar spine BMD from baseline at 12 months was the greatest in the ROMO group (ROMO: 8.6 [3.1-12.4]%, DMAb: 3.3 [1.5-6.2]%, BP: -0.4 [-3.4-1.1]%). Among bone formation markers, serum levels of bone alkaline phosphatase were slightly elevated in the ROMO group, whereas those of N-terminal propeptide of type I procollagen and osteocalcin decreased in all 3 groups; however, these changes were smaller in the ROMO group. Serum levels of bone resorption markers and a urine bone quality marker decreased in all groups.

CONCLUSION

Treatment with ROMO significantly increased lumbar spine BMD in glucocorticoid-treated patients, suggesting that ROMO is effective for GIOP.

CLINICAL TRIAL NUMBER

UMIN000037239.