For patients with rheumatoid arthritis (RA) who are treated with biologics, the risk for serious infection is not significantly higher with certolizumab pegol, as had previously been suggested, according to results published online in the Annals of the Rheumatic Diseases.
Although the rate of serious infection for participants taking certolizumab pegol was lower compared with patients taking etanercept in the primary analysis, these results were not statistically significant after the researchers performed several sensitivity analyses.
The study used data from the British Society for Rheumatology Biologics Register for Rheumatoid Arthritis. The study included patients with RA who started a new biologic medication (n=19,282). The primary outcome was serious infection, which the researchers defined as an infectious event requiring admission to a hospital, requiring intravenous antibiotics, or resulting in death. Secondary outcomes included the rate of infection by organ class and 30-day mortality following infection.
Of the 19,282 participants and 46,771 years of follow-up, the incidence of serious infection was 5.51 cases for 100 patient-years (95% CI, 5.29-5.71). Participants taking tocilizumab had a higher risk for serious infection compared with participants taking etanercept (hazard ratio [HR] 1.22; 95% CI, 1.02-1.47).
Participants taking certolizumab pegol had a lower risk for serious infection compared with participants taking etanercept (HR 0.75; 95% CI, 0.58-0.97).
The 30-day mortality following serious infection was 10.4% (95% CI, 9.2%-11.6%).
“For patients whose baseline risk of infection is low, the choice of biologic will have very little impact on their subsequent infection risk,” the researchers wrote. “However, for patients with multiple risk factors who have a high baseline risk of infection, then choosing a drug with a slightly higher relative risk of infection can have a much larger impact on their infection risk.”
Rutherford AI, Subesinghe S, Hyrich KL, Galloway JB. Serious infection across biologic-treated patients with rheumatoid arthritis: results from the British Society for Rheumatology Biologics Register for Rheumatoid Arthritis. [published online March 28, 2018]. Ann Rheum Dis. doi:10.1136/ annrheumdis-2017-212825