To evaluate the efficacy and safety of sarilumab plus conventional synthetic disease-modifying antirheumatic drugs (DMARDs) in patients with active moderate-to-severe rheumatoid arthritis (RA) who had an inadequate response or intolerance to anti-tumor necrosis factor (anti-TNF) therapy.
Patients were randomly allocated to receive sarilumab 150 mg, sarilumab 200 mg, or placebo every 2 weeks for 24 weeks with background conventional synthetic DMARDs. The co-primary end points were the proportion of patients achieving a response according to the American College of Rheumatology 20% criteria for improvement (ACR20) at week 24, and change from baseline in the Health Assessment Questionnaire disability index (HAQ DI) at week 12. Each sarilumab dose was evaluated against placebo; differences between the 2 sarilumab doses were not assessed.
The baseline characteristics of the treatment groups were similar. The ACR20 response rate at week 24 was significantly higher with sarilumab 150 mg and sarilumab 200 mg every 2 weeks compared with placebo (55.8%, 60.9%, and 33.7%, respectively; P < 0.0001). The mean change from baseline in the HAQ DI score at week 12 was significantly greater for sarilumab (least squares mean change: for 150 mg, -0.46 [P = 0.0007]; for 200 mg, -0.47 [P = 0.0004]) versus placebo (-0.26). Infections were the most frequently reported treatment-emergent adverse events. Serious infections occurred in 1.1%, 0.6%, and 1.1% of patients receiving placebo, sarilumab 150 mg, and sarilumab 200 mg, respectively. Laboratory abnormalities included decreased absolute neutrophil count and increased transaminase levels in both sarilumab groups compared with placebo. In this study, reductions in the absolute neutrophil count were not associated with an increased incidence of infections or serious infections.
Sarilumab 150 mg and sarilumab 200 mg every 2 weeks plus conventional synthetic DMARDs improved the signs and symptoms of RA and physical function in patients with an inadequate response or intolerance to anti-TNF agents. Safety data were consistent with interleukin-6 receptor blockade and the known safety profile of sarilumab.