Objectives: We report results of subgroup analyses of bone mineral density (BMD) and bone turnover markers from a randomized, 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 60mg (n=71), or denosumab 180mg (n=72) at baseline and 6 months. Assessments included dual X-ray absorptiometry scans of the lumbar spine and hip, 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 versus 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.