Objective. To compare tumor necrosis factor ␣ inhibitors directly regarding the rates of treatment response, remission, and the drug survival rate in patients with rheumatoid arthritis (RA), and to identify clinical prognostic factors for response.Methods. The nationwide DANBIO registry collects data on rheumatology patients receiving routine care. For the present study, we included patients from DANBIO who had RA (n ‫؍‬ 2,326) in whom the first biologic treatment was initiated (29% received adalimumab, 22% received etanercept, and 49% received infliximab). Baseline predictors of treatment response were identified. The odds ratios (ORs) for clinical responses and remission and hazard ratios (HRs) for drug withdrawal were calculated, corrected for age, disease duration, the Disease Activity Score in 28 joints

In 802 arthritis patients treated with INX for median >6 years, a nationwide non-medical switch to CT-P13 had no negative impact on disease activity. Adjusted 1-year CT-P13 retention rate was slightly lower than for INX in a historic cohort.

ObjectivesReal-world evidence on effectiveness of switching to biosimila r etanercept is scarce. In Denmark, a nationwide guideline of mandatory switch from 50 mg originator (ETA) to biosimilar (SB4) etanercept was issued for patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA) in 2016. Clinical characteristics and treatment outcomes were studied in ETA-treated patients, who switched to SB4 (switchers) or maintained ETA (non-switchers). Retention rates were compared with that of a historic cohort of ETA-treated patients. Switchers who resumed ETA treatment (back-switchers) were characterised.MethodsObservational cohort study based on the DANBIO registry. Treatment retention was explored by Kaplan-Meier plots and Cox regression (crude, adjusted).Results1621 (79%) of 2061 ETA-treated patients switched to SB4. Disease activity was unchanged 3 months’ preswitch/postswitch. Non-switchers often received 25 mg ETA (ETA 25 mg pens/syringes and powder solution were still available). One-year adjusted retention rates were: non-switchers: 77% (95% CI: 72% to 82%)/switchers: 83% (79% to 87%)/historic cohort: 90% (88% to 92%). Patients not in remission had lower retention rates than patients in remission, both in switchers (crude HR 1.7 (1.3 to 2.2)) and non-switchers (2.4 (1.7 to 3.6)). During follow-up, 120 patients (7% of switchers) back-switched to ETA. Back-switchers’ clinical characteristics were similar to switchers, and reasons for SB4 withdrawal were mainly subjective.ConclusionSeventy-nine per cent of patients switched from ETA to SB4. After 1 year, adjusted treatment retention rates were lower in switchers versus the historic ETA cohort, but higher than in non-switchers. Withdrawal was more common in patients not in remission. The results suggest that switch outcomes in routine care are affected by patient-related factors and non-specific drug effects.