Effects of denosumab on bone mineral density and bone turnover in patients with rheumatoid arthritis receiving concurrent glucocorticoids or bisphosphonates

Objectives To report results of subgroup analyses of bone mineral density (BMD) and bone turnover markers from a randomised, double-blind, placebo-controlled, phase II study of denosumab, an investigational RANKL inhibitor, in patients with rheumatoid arthritis (RA) concurrently receiving treatment with bisphosphonates or glucocorticoids. Methods Patients received subcutaneous placebo (n=75), denosumab 60 mg (n=71) or denosumab 180 mg (n=72) at baseline and 6 months. Assessments included dual x-ray absorptiometry scans of the lumbar spine and hip, and determination of levels of serum type I C-telopeptide (sCTx-I) and serum procollagen 1N-terminal peptide (P1NP). Results Denosumab treatment increased mean lumbar spine and hip BMD and reduced sCTx-I and P1NP compared with placebo through 12 months, regardless of baseline BMD or marker levels or concomitant bisphosphonate or glucocorticoid use. Conclusions This study extends evidence that denosumab increases BMD and reduces bone turnover in patients with RA and may provide a new therapeutic option for reducing systemic bone loss in patients with RA.