SAT0146 COMPARING DRUG SURVIVAL FOR BIOSIMILAR SB4 ETANERCEPT IN RHEUMATOID ARTHRITIS BOTH ETANERCEPT NAïVE AND NON-MEDICAL SWITCH PATIENTS WITH ETANERCEPT REFERENCE DRUG IN A NORWEGIAN OUT-PATIENT CLINIC. PRELIMINARY RESULTS FROM A MULTI-CENTER STUDY
Authors: Glenn Haugeberg, Bjørg Tilde Svanes Fevang, Gunnstein Bakland, Erik Rødevand, Andreas Diamantopoulos
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background:</h3> In Norway encouraged by the health authorities non-medical switch from reference drug to biosimilar drug has been performed in most patients on biologic reference drugs with biosimilar drugs available, including etanercept. There is a need for real life data understanding the effect of biosimilar drugs when these drugs are introduced in clinical practice. <h3>Objectives:</h3> To explore drug survival for biosimilar SB4 etanercept in RA patients, both etanercept naïve and non-medical switch patients, and compare with the etanercept reference drug. <h3>Methods:</h3> Preliminary 2 years drug survival data from one center in a 5 center study in Norway exploring drug survival for etanercept reference drug and biosimilar etanercept SB4 is presented. At this outpatient clinic RA patients as part of standard clinical care has been monitored systematically since 2003. Drug survival for SB4 etanercept, both the etanercept naïve and the non-medical SB4 switch group, was compared with patients treated with the etanercept reference drug in the period 2003-2018. Baseline demographic, clinical and treatment data were retrieved and analyzed. Kaplan-Meier survival curves were used to explore 2 years drug survival. Survival differences between groups were tested using Breslow statistics. <h3>Results:</h3> At the outpatient clinic the number of RA patients treated with etanercept reference drug was 356, the number of patients treated with SB4 with no previous etanercept was 36 and the patients with a non-medical switch from reference etanercept to etanercept SB4 was 84. In the table below baseline demographics and disease measures are shown for the etanercept reference group, the non-medical SB4 switch group and the SB4 naïve to etanercept group. Data in table are presented as percentage for group variables and as mean with standard deviation (SD) for continuous variables. Mean (95%CI) drug survival for the non-medical SB4 switch group was1.53 (1.38-1.68) years, for the SB4 group with no previous etanercept 1.23 (0.95-1.51) years and for etanercept reference group 1.38 (1.31-1.46) years. A statistically significant difference (p&lt;0.02) was found between the groups except between etanercept reference group and the etanercept SB4 group without prior etanercept (p=0.23). The percentage of RA patients starting with etanercept as first biologic drug was for etanercept reference 64.6% and for biosimilar etanercept SB4 36.1%. In the figure below Kaplan-Meier drug survival curves are shown. <h3>Conclusion:</h3> To the best of our knowledge this is the first data showing that drug survival of an etanercept biosimilar drug after a non-medical switch is higher than a historical cohort of etanercept reference drug. This is expected, since it is a selected group of etanercept responders. The interpretation of the results should be cautious, since only few patients are included in this first analysis. A larger number of patients from other participating out-patient clinics is planned to be included. <h3>Disclosure of Interests:</h3> Glenn Haugeberg Grant/research support from: For this study grant from Biogen, Consultant for: Medical Advisory boards for several companies, Paid instructor for: I have been paid for giving lectures for pharmaceutical companies and their employees, Speakers bureau: I have been paid for giving lectures in meetings organized by pharmaceutical companies, Bjørg Tilde Svanes Fevang: None declared, Gunnstein Bakland: None declared, Erik Rødevand: None declared, Andreas Diamantopoulos: None declared