Tocilizumab Inhibits Structural Joint Damage in Rheumatoid Arthritis Patients With Inadequate Responses to Methotrexate Results From the Double-Blind Treatment Phase of a Randomized Placebo-Controlled Trial of Tocilizumab Safety and Prevention of Structural Joint Damage at One Year

Objective. To assess the efficacy and safety of tocilizumab plus methotrexate (MTX) versus MTX alone in preventing structural joint damage and improving physical function and disease activity in patients with moderate-to-severe rheumatoid arthritis and inadequate responses to MTX. Methods. A total of 1,196 patients were enrolled in a 2-year, randomized, double-blind, placebo-controlled trial. Patients received tocilizumab (8 mg/kg or 4 mg/kg) or placebo every 4 weeks plus MTX. Rescue treatment was available from week 16. Results from year 1 are presented. Results. Mean change in the total Genant-modified Sharp score was 0.29 and 0.34 with tocilizumab 8 mg/kg plus MTX and 4 mg/kg plus MTX, respectively, versus 1.13 with placebo plus MTX (P < 0.0001 for both comparisons). Analysis of variance of the area under the curve for change from baseline in the disability index of the Health Assessment Questionnaire showed greater decreases with tocilizumab 8 mg/kg and 4 mg/kg (-144.1 and -128.4 units, respectively) than with placebo (-58.1 units; P < 0.0001 for both comparisons). Proportions of patients with American College of Rheumatology 20%, 50%, and 70% improvement and with Disease Activity Score in 28 joints remission were higher in those receiving 8 mg/kg tocilizumab than in those receiving placebo (P < 0.0001 for all comparisons). The safety profile of tocilizumab was consistent with the profiles in previous studies. Infections were the most common adverse and serious adverse events. Conclusion. The findings of this study show that tocilizumab plus MTX results in greater inhibition of joint damage and improvement in physical function than does MTX alone. Tocilizumab has a well-characterized safety profile.