Investigation of treatment continuity, usefulness, and nocebo effect in switching from the original etanercept to its biosimilar in patients with rheumatoid arthritis: A JET observational study in Japanese clinical practice.

Objectives: To assess the usefulness and onset of nocebo effects after switching from the original etanercept (ETN) to a biosimilar (BS) in routine clinical practice at rheumatology clinics in Japan (13 sites). Methods: A total of 165 patients (87.0% women, age = 57.88 ± 15.07 years, and disease duration = 10.32 ± 7.71 years), whose low disease activity was maintained with the original ETN for ≥12 weeks, and who agreed to switch treatment to its BS, were included. The end-points were disease activity score 28 (DAS28)-C-reactive protein and DAS28-erythrocyte sedimentation rate. Results: No significant difference was observed between the changes in DAS28-C-reactive protein and DAS28-erythrocyte sedimentation rate >12 weeks before switching and >12 weeks after switching (P = 0.132 and 0.334, respectively). The treatment continuation rate during the 52 weeks after switching to BS was 97.3%. During this period, BS was discontinued in only four patients, and no nocebo effects were suspected in these four patients. Conclusion: Switching from ETN to BS was effective even in routine clinical practice at rheumatology clinics in Japan, and no nocebo effects were observed. Sufficient explanations to patients by rheumatologists and the additional payment for drug costs between patients at hospital visits effectively improved the continuation rate without any nocebo effect. [ABSTRACT FROM AUTHOR]