Biological disease-modifying drugs and denosumab: an infection risk for rheumatoid arthritis?

This study investigated if patients with rheumatoid arthritis had an increased risk of serious infection when treated with denosumab (Xgeva) or biological DMARDs.

They found that there was a low incidence of serious infection in patients taking denosumab and/or biological DMARDs.

Rheumatoid arthritis (RA) is a condition that affects the joints. In RA, the body produces chemical mediators that lead to inflammation. This leads to loss of joint tissue, causing pain and impairing normal function.

To treat RA, patients are prescribed drugs that reduce inflammation. One type are called biological disease-modifying anti-rheumatic drugs (bDMARDs). Another feature of RA is bone density loss. Many patients with RA also show signs of bone loss that can lead to osteoporosis. To treat this, many RA patients are prescribed denosumab. This medication works by preventing cells called osteoclasts from ‘digesting’ bone tissue and thus slowing the loss of bone mass.

Both bDMARDs and denosumab work by suppressing the immune system and as a result there may be an increased risk of infection in patients with RA taking these medications.

This study investigated if there is an increased incidence of serious infection in patients with RA taking bDMARDs and denosumab. This study included data from 308 patients. 102 patients were treated with both bDMARDs and denosumab and 206 were treated with bDMARDs alone. The number of hospital admissions were monitored for 12 months before and until the end of the trial (a further 3 years, approximately).

Patients taking both bDMARDs and denosumab had a low incidence of serious infection (3 out of 102 patients). This was similar to patients taking bDMARDs alone (4 out of 206 patients). The risk of infection was not significantly different between the two groups.

This study concluded that there was a low incidence of serious infection in patients taking denosumab and/or biological DMARDs.

This is a relatively small study; larger, long-term studies may be needed. 

If you have any concerns regarding treatment for RA and infection risk, please consult with your physician.