PurposeThe aim was to compare outcomes in adult patients with inflammatory bowel disease (IBD) who switched to infliximab-dyyb with those who remained on reference product (RP) infliximab in the United States (US) in a retrospective, propensity score-matched, non-inferiority cohort trial.MethodsThis study was a retrospective, non-inferiority study conducted within a US integrated healthcare system and included adult patients with a confirmed diagnosis of Crohn’s disease or ulcerative colitis. A 1:1 propensity score matching was utilized to match patients who switched to infliximab-dyyb during the period April 2016–March 2018 to patients who remained on RP infliximab. The non-inferiority margin was set at + 10% of the upper limit. The primary outcome was a composite measure of disease worsening requiring acute care after the index date of switching to infliximab-dyyb or continuing RP infliximab. Disease worsening requiring acute care was defined as any IBD-related emergency room visit, hospitalization, or surgery. The secondary outcome was the composite measure of disease worsening requiring acute care or treatment failure. A switch to another biologic or tofacitinib was a proxy for treatment failure. All patients were followed for up to 9 months.ResultsAfter propensity score matching, the matched cohort included 1409 patients in the infliximab-dyyb group and 1409 patients in the RP infliximab group. The overall mean age (± standard deviation) was 47.7 ± 17.0 years, 50.9% of patients were of male gender, and 51.8% of patients had Crohn’s disease, while the remainder of the cohort had ulcerative colitis. There were 144 patients (10.2%) in the infliximab-dyyb group and 245 patients (17.4%) in the RP infliximab group who experienced disease worsening requiring acute care (P < 0.01 for non-inferiority). There were 347 patients (24.6%) in the infliximab-dyyb group who experienced disease worsening requiring acute care or treatment failure compared to 375 patients (26.6%) who remained on RP infliximab (P < 0.01 for non-inferiority).ConclusionThere was no increased risk of (1) disease worsening requiring acute care or (2) disease worsening requiring acute care or treatment failure in patients with IBD who switched from RP infliximab to infliximab-dyyb when compared to patients who remained on RP infliximab in this US population. Infliximab-dyyb is an option for patients with IBD who need to use RP infliximab.