Median time to low disease activity is shorter in tocilizumab combination therapy with csDMARDs as compared to tocilizumab monotherapy in patients with active rheumatoid arthritis and inadequate responses to csDMARDs and/or TNF inhibitors: sub-analysis of the Swiss and Austrian patients from the ACT-SURE study

To analyse efficacy and safety of tocilizumab in patients with rheumatoid arthritis (RA) and an inadequate response to conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) and/or tumour necrosis factor (TNF) inhibitors of the Swiss and Austrian patients from the ACT-SURE study. This is a sub-analysis of RA patients from Switzerland and Austria, who participated in the international phase 3b, open-label, ACT-SURE study. Patients with an inadequate response to csDMARDs or TNF antagonists receiving 8 mg/kg of IV tocilizumab every 4 weeks during a 24-week time period were included into the study. Therapy with one or more csDMARDs could be continued as combination therapy with tocilizumab (Combo) or stopped, resulting in tocilizumab monotherapy (Mono), at the treating physician’s discretion. These two patient groups were analysed in separate and compared. Overall, 107 (22 on Mono vs. 85 on Combo) patients were treated with tocilizumab. The percentage of patients with at least one adverse event was significantly lower in the tocilizumab combination (58.8%) as compared to the monotherapy group (81.8%, p = 0.0458). No differences in ACR20/50/70/90 response rates were observed between both treatment groups at week 24 (Mono 63.6, 40.9, 22.7, and 18.2% vs. Combo 61.2, 43.5, 25.9, and 10.6%). The median time to low disease activity (LDA) was significantly shorter in patients treated with tocilizumab combination therapy (Mono 9.1, Combo 7.9 weeks, log rank p = 0.038). In this post hoc regional sub-analysis of the ACT-SURE study, no differences for disease activity were found comparing the two patient groups at week 24. However, median time to LDA was statistically shorter in patients treated with tocilizumab combination therapy as compared to tocilizumab monotherapy. Consequently, adding tocilizumab to csDMARD therapy rather than changing to tocilizumab monotherapy may be, in our opinion, the safest strategy to reach maximum effect in RA patients with active disease despite treatment with csDMARD. csDMARDs can be withdrawn either immediately due to adverse events or after at least low disease activity has been reached.