SAT0199 Switch from innovator etanercept to biosimilar etanercept in inflammatory rheumatic diseases: the experience of cochin university hospital paris-france.
Authors: O. Al Tabaa, A. Etcheto, C. Miceli-Richard, M. Anna, M. Dougados
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background:</h3> Etanercept biosimilar (bETN) is available for treatment of spondyloarthritis (SpA) and rheumatoid arthritis (RA) since 2016 in France. Data showing effectiveness and safety of bETN are still limited. <h3>Objectives:</h3> 1/To evaluate the RA and SpA patients' and treating rheumatologists' characteristics associated with the switch 2/To evaluate the safety and efficiency of bETN. <h3>Methods:</h3> Patients: All the patients receiving innovator etanercept for at least 3 months on October 2016 and monitored in the department of rheumatology B of Cochin hospital. Physicians: All the 9 physicians in charge of at least one patient. Study design: After information (one hour session) on the biosimilars, all the physicians were invited to propose a switch from innovator etanercept to bETN. Data collected: physicians' characteristics, patients' characteristics (demographics, diagnosis of the rheumatic disease, disease activity parameters). <h3>Results:</h3> Of the 435 outpatients who had received etanercept; 304 were receiving etanercept in 2016 and 183 were eligible for a potential switch (the remaining 121 patients did not attend any out-patient-clinic between October 1st 2016 and April 1st 2017). The percentage of patients who switched to bETN was 51.6% (94 patients). This switch was more frequently performed in patients monitored by older physicians (mean age: 50.4±14.3 <i>vs</i> 44.8±11.3, p=0.005) and by physicians with a full-time academical position (56.4 % <i>vs</i> 13.5 %, p&lt;0.001) The patients' characteristics were similar: % RA (51.1% <i>vs</i> 44.9%), age (52.1±15 <i>vs</i> 50.5±15), female gender (57.4% <i>vs</i> 51.6%), disease duration (16.8±11.9 <i>vs</i> 14.8±11.3) except for the NSAID intake (28.3 % <i>vs</i> 12.3 %, p=0.014) and the global evaluation (25.2±19.4 <i>vs</i> 19.1±21.8, p=0.02) in the switchers vs non-switchers, respectively. However, no independent factors were associated with the switch in the multivariate analysis. The bETN retention rate was 83 % [0.76–0.92] after a 6 month follow-up period. The bETN was discontinued in 26 patients with the following reasons: inefficiency 13 patients, adverse event 13 patients (painful injection site n = 4, fatigue = 2, pruritus n = 2, "allergic reaction" n =1, headache n = 1, pollakiuria n = 1, dizziness n = 1, supply problem n = 1). The univariate analysis aimed at evaluating the baseline predisposing factors of bETN discontinuation overtime picked up the baseline objective sign of inflammation (defined by CRP≥6 mg/L or ESA ≥28 mm) (OR=4.18 [1.19 – 14.66] p=0.0256), p=0.002) and global disease activity score (OR = 1.57 [1.04 – 2.36], p=0.03). Nevertheless, no independent factors were associated with the switch in the multivariate analysis. There was no difference in the changes in the disease activity parameters in both the completer and ITT population. <h3>Conclusions:</h3> This study suggests that: 1/The probability to switch from etanercept innovator to bETN was mainly related to physicians' behavior 2/Using an open design, the percentage of patients complaining of a lower efficiency and/or a worse safety profile of the biosimilar was high 3/There was no objective parameter permitting to conclude at a lower efficiency and/or a worse safety profile of the bETN in comparison to the innovator etanercept. <h3>Disclosure of Interest:</h3> None declared