A Systematic Switch From Originator Infliximab to Biosimilar Infliximab in Patients With Non-

center dot PURPOSE: To investigate the efficacy of biosimilar infliximab compared to that of the originator infliximab for the treatment of chronic non-infectious uveitis. center dot DESIGN: Before-and-after study. center dot METHODS: All patients in the Central Norway Health Region between 2007 and 2018 were included. They were switched from originator to biosimilar infliximab therapy from 2014 to 2017. The primary outcome was quiescence of uveitis before and after the switch. All patients were seen every 1-3 months. Visits were binned into 3-month long periods for each patient takingboth medications. Poisson regression analysis was used to estimate the incidence rate ratio (IRR) of quiescence between the 2 treatments. center dot RESULTS: Twenty-nine patients were treated with infliximab. Twenty-three of those patients were switched from originator to biosimilar infliximab. The majority were white (87%), female (92%), and had chronic anterior uveitis (65%). For patients taking the originator and biosimilar drugs, the median treatment duration was38 months (range: 8-131 months) and 15 months (range: 5-55 months), respectively. Concomitant immunosuppressive medications and topical and oral steroids were used similarly during treatment with both originator and biosimilar infliximab. The IRR for quiescence was 0.91 (95% confidence intervals [CI]: 0.7-1.1; P = 0.38), which indicated no statistically significant differences in achieving quiescence after the switch. Also, there were no differences in the incidence rate of flare events with the switch (IRR: 1.04; 95% CI: 0.36-2.98; P = 0.95). IRR adjusted for intraocular surgery was 0.90 (95% CI: 0.7-1.1; P = 0.37). center dot CONCLUSIONS: No evidence of differences in effectiveness were found in comparing biosimilar to originator infliximab in patients with chronic non-infectiousuveitis. (Am J Ophthalmol 2021;225:178-184. (c) 2020 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).)