How effective is denosumab treatment in patients with rheumatoid arthritis?

This review evaluated the effectiveness of denosumab (Prolia) on bone mineral density (BMD) and joint destruction in patients with rheumatoid arthritis (RA). The authors concluded that denosumab treatment was linked to increased BMD and reduced joint destruction in patients with RA.

RA is a chronic inflammatory disease affecting joints. It leads to joint destruction and impaired quality of life (QoL). Disease-modifying anti-rheumatic drugs (DMARDs) such as conventional synthetic DMARDs (csDMARDs) and biological DMARDs (bDMARDs) provide partial protection against progressive joint destruction. Further, they suppress the immune system which can cause infections and side effects.

RA is also associated with osteoporosis (reduced bone mineral density; BMD). Osteoporosis leads to brittle bones and an increased risk of fractures. Denosumab is an antiresorptive agent used to treat osteoporosis. However, initial clinical trial results investigating the effects of denosumab treatment in patients with RA have been inconsistent and require further clarification.

This review analyzed the results of 10 studies with a total of 1758 patients with RA. 5 studies compared denosumab treatment with placebo. 5 studies compared denosumab treatment with bisphosphonates (other drugs for osteoporosis treatment). Changes from baseline measurements were made for BMD, and the degree of joint destruction. The average follow-up time for patients was 13 months.

On average, a 5.12% improvement in lumbar spine BMD occurred with denosumab treatment compared to controls. There was a 2.82% increase in total hip BMD and a 2.2% increase in femoral neck BMD compared to controls. Significant decreases occurred in joint destruction scores in the denosumab group. 

The study showed that denosumab treatment was associated with higher lumbar spine, total hip and femoral neck BMD and decreased joint destruction in patients with RA.

The study had a relatively short follow-up period. Denosumab was compared with bisphosphonates in half of the studies. The study design of 5 studies may have influenced interpretation of results. Additional, large, randomized studies are needed.