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

Biomarkers are important for guiding the clinical and therapeutic management of all phases of rheumatoid arthritis because they can help to predict disease development in subjects at risk, improve diagnosis by closing the serological gap, provide prognostic information that is useful for making therapeutic choices and assessing treatment responses and outcomes, and allow disease activity and progression to be monitored. Various biomarkers can be used to identify subjects susceptible to the disease and those with pre-clinical rheumatoid arthritis before the onset of symptoms such as rheumatoid factor and anti-citrullinated protein antibodies. They can be correlated with a risk of developing rheumatoid arthritis and can predict more bone erosions and severe disease progression. Biomarkers such as the erythrocyte sedimentation rate and C-reactive protein levels provide information about disease activity, while predictive biomarkers allow clinicians to assess the probability of a treatment response before starting a particular therapy particularly in the era of biological drugs. This move from traditional approaches to patient stratification and targeted treatment should greatly improve patient care and reduce medical costs.

Long-term extension studies and observational drug registers have revealed an increased risk of serious infections in patients treated with anti-tumor necrosis factor agents, particularly infliximab, etanercept and adalimumab. The same may be true for the newer biological drugs rituximab, tocilizumab and abatacept, although this has yet to be confirmed by long-term observational studies. We review the risk of tuberculosis, herpes zoster and other opportunistic infections, and the recommendations for screening for tuberculosis and hepatitis B and C infections in patients affected by rheumatoid arthritis, with the aim of informing patients and encouraging greater awareness among physicians.