Risk of infections in rheumatoid arthritis patients treated with tocilizumab

Objectives. To investigate the occurrence and risk factors for infections in RA patients treated with tocilizumab. Methods. A cohort of all RA patients (n = 112) starting tocilizumab therapy between October 2008 and March 2010 in Northern Bavaria was screened for infections. Mild/moderate and severe infections were recorded. Multivariate logistic regression analysis was used to define risk factors for infection. Results. Overall, 26 patients developed infections [23.2%; 58.0/100 patient-years (py)], 18 of them were mild to moderate (16.1%, 40.1/100 py) and 8 were severe (17.9/100 py). Concomitant use of LEF and prednisone, high disease activity and previous therapy with rituximab were associated with the occurrence of mild/moderate infections. Severe infections were related to longer disease duration, exposure to more than three previous DMARDs and concomitant therapy with proton-pump inhibitors. Conclusion. The rate of infection in RA patients treated with tocilizumab in clinical practice is higher than in the clinical trial populations. Increased attention should especially be given to patients with longer disease duration, previous exposure to multiple DMARDs, i.e. previous exposure to rituximab and those receiving concomitant LEF, prednisone or proton-pump inhibitor treatment.