Israel Medical Association Journal

Background: There is a lack of real-life clinical data for biosimilar etanercept, an anti-TNF blocking fusion protein. We describe the comparable efficacy and safety of originator and biosimilar etanercept in rheumatoid arthritis (RA) patients in a real-life clinical setting. Our data confirm that a biosimilar etanercept can be safely used as first-line treatment as well as in patients switched from a previous originator compound.

Objectives: To compare the efficacy and safety of originator and biosimilar etanercept in a cohort of RA patients attending two Italian hospitals.

Methods: The study involved 81 consecutive adult RA patients treated for at least 6 months with originator or biosimilar etanercept and considered their clinical and laboratory data, concomitant medications, and adverse events at baseline, and after 3 and 6 months of treatment.

Results: Group 1 included 51 patients taking originator etanercept; group 2 included 30 taking biosimilar etanercept, including 19 who had been switched from the reference product. Despite a significant baseline difference in clinical disease activity, one-way analysis of variance showed that the two groups were clinically comparable after 6 months of treatment, and the same was true when only those receiving etanercept as first-line biological treatment were considered. Nine patients discontinued the treatment due to inefficacy or adverse events, which were never serious and were only reported in group 1.

Conclusions: The efficacy and safety profiles of originator and biosimilar etanercept are comparable in RA patients in a real-life clinical setting. Further studies are needed to confirm these preliminary findings

Background: Targeted anti-tumor necrosis factor-alpha (TNFα) therapy in patients with rheumatoid arthritis (RA) has resulted in dramatic improvement in the course of the disease and prognosis. One of the features of RA is hyperplasia of synovial cells, particularly RA synovial fibroblasts (RA-SF), caused partially by impaired apoptosis of RA-SF cells. It has been shown that TNFα may inhibit apoptosis in RA-SF cells and this process may be reversed by the use of TNFα antagonists.

Objectives: To determine the influence of etanercept, an anti-TNFα agent, on sFas (CD 95) receptor.

Methods: We analyzed serum levels of sFaS and TNFα in a group of 26 patients with high RA disease activity who were selected to start treatment with etanercept. Assessment of sFas receptor and TNFα levels was performed before and 6 months after treatment with etanercept.

Results: Treatment with etanercept resulted in increased TNFα levels (log TNFα 0.602 vs. 1.17, P < 0.05) but no change in sFas levels (log sFas 3.17 vs. 3.11, P = 0.37). As expected, treatment resulted in significant reduction in both disease activity and levels of inflammatory markers.

Conclusions: Etanercept may increase TNFα levels in patients with RA. We also speculate that the Fas pathway is not the main apoptotic pathway in patients with RA treated with etenercept, since sFas, a marker of apoptotic activity, remained unchanged and was not influenced by disease activity and concomitant treatment. 

There is accumulating evidence that tumor necrosis factor plays a major role in the pathogenesis of rheumatoid arthritis. Recent biotechnological advances have allowed for the development of agents that directly target TNF, a pro-inflammatory cytokine. In the last 2 years, the U.S. Food and Drug Administration and the European Union’s Commission of the European Communities have approved two biological agents for the treatment of refractory RA, etanercept and infliximab. Etanercept is a fusion protein, composed of the Fc portion of immunoglobulin G1 and the extracellular domain of a TNF receptor (p75). Infliximab is a chimeric monoclonal antibody composed of murine variable and human constant regions. In placebo-controlled trials, both agents have proven to be effective and well tolerated in PA patients.