To evaluate the 12-year survival of the first tumor necrosis factor inhibitor (TNFi) treatment in a cohort of rheumatoid arthritis (RA) patients, comparing the between-groups discontinuation rates for infliximab, etanercept, and adalimumab.
RA patients treated with their first TNFi were investigated from a local registry. Before and after adjusting for propensity scores, overall and by individual TNFi 12-year drug retention was evaluated. Drug survival rates were calculated using the Kaplan-Meier method and compared by the Cox extended model. Subanalyses were performed according to concomitant methotrexate (MTX) and discontinuation reasons.
Of 583 patients, 222 were treated with infliximab, 179 with etanercept, and 182 with adalimumab; 33.7% and 26% discontinued the first TNFi because of inefficacy or adverse events, respectively. The overall 12-year drug survival rate for the unmatched population was 23.4%. In the propensity score-adjusted population, the hazard ratio (HR) for treatment discontinuation was significantly greater for adalimumab and infliximab versus etanercept (HR 2.89 [95% confidence interval (95% CI) 2.2-3.78] and HR 2.56 [95% CI 1.92-3.4], respectively), and no difference was found between and for adalimumab versus infliximab (HR 1.16 [95% CI 0.91-1.47]). The incidence of withdrawal due to secondary inefficacy was stable from 3 to 12 years for etanercept, but progressively increased for the monoclonal antibodies. Concomitant MTX significantly increased the survival of both adalimumab and etanercept (HR 1.48 [95% CI 1.18-1.86]).
The overall 12-year drug survival rate was 23.4%, being significantly higher for etanercept than adalimumab and infliximab. Etanercept discontinuations for inefficacy did not increase from 3 to 12 years. Concomitant MTX increased adalimumab and etanercept drug survival.