Comparative effectiveness of TNF inhibitors and tocilizumab with and without conventional synthetic disease-modifying antirheumatic drugs in a pan-European observational cohort of bio-naïve patients with rheumatoid arthritis

Objectives: To compare treatment effectiveness in rheumatoid arthritis (RA) patients naïve to biological disease-modifying antirheumatic drugs (bDMARDs) treated with tocilizumab (TCZ) or TNF-inhibitor (TNFi) with (-combo) or without (-mono) conventional synthetic DMARDs (csDMARDs). Methods: Patients with RA across 7 European registries, naïve to bDMARDs who initiated treatment with TCZ or TNFi from 2009 to 2016 were included. Drug retention rate was analyzed using Kaplan–Meier and Cox models, and CDAI over time by mixed models. The proportions of patients reaching CDAI low disease activity (LDA) and remission after one year were corrected for attrition. Results: 6713 TNFi-combo, 3762 TNFi-mono, 646 TCZ-combo and 384 TCZ-mono were eligible. Crude median retention was 3.67 years (95%CI 3.41–3.83) for TNFi-combo, 4.14 (3.77–4.62) for TNFi-mono, 2.98 (2.76–3.34) for TCZ-combo and 3.63 years (3.34–5.03) for TCZ-mono. After adjustment for covariates, country and year of treatment initiation stratification, hazards of discontinuation were lower for TCZ-mono (0.60, 95% CI 0.52–0.69) and TCZ-combo (0.66, 95% CI 0.54–0.81) compared to TNFi-combo. Adjusted CDAI evolution was not significantly different between groups. CDAI LDA and remission corrected for attrition were similar between TCZ with or without csDMARDs and TNFi-combo. Conclusion: In routine care across 7 European countries, the adjusted drug retention, adjusted CDAI over time and attrition-corrected response proportion for RA patients were similar for bio-naïve patients if treated with TNFi-combo, TCZ-combo or TCZ-mono.