Impact of Infliximab-dyyb (Infliximab Biosimilar) on Clinical and Patient-Reported Outcomes: 1-Year Follow-up Results from an Observational Real-World Study Among Patients with Inflammatory Bowel Disease in the US and Canada (the ONWARD Study)

Introduction To date, there are limited real-world studies published on the use of infliximab-dyyb, a biosimilar to reference product (RP) infliximab approved for the treatment of moderate to severe inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC) in North America. This study examined utilization patterns and the effects of infliximab-dyyb on clinical outcomes, patient-reported outcomes (PROs), and healthcare resource use (HCRU) in IBD patients in a real-world setting. Methods In this prospective, observational study, adult IBD patients in the US and Canada were recruited to initiate treatment with infliximab-dyyb and followed for 12 months. Patients included biologic-naive users of infliximab-dyyb and patients switching from RP infliximab or other biologics to infliximab-dyyb. Partial Mayo (pMAYO) and Harvey Bradshaw Index (HBI) scores measured clinical outcomes for the UC and CD cohorts, respectively. Key PRO measures included the SIBDQ, EQ-VAS, and psychological outcomes. In addition, work productivity, HCRU, and adverse events (AEs) were assessed. Results A total of 67 CD and 48 UC patients were enrolled (51% female; mean age 44 years; 87% Caucasian; mean BMI 27.9). Thirty-nine patients were biologic-naive, 57 switched from RP infliximab, and 19 switched from other biologics. Among UC biologic-naive users, pMAYO decreased from 5.67 to 1.09 (p < 0.0001) and the remission rate increased from 5.6 to 90.9% (p = 0.0015). For UC patients switching from RP infliximab, pMAYO decreased from 1.38 to 0.29 (p = 0.0103). For CD biologic-naive users, HBI scores and remission rates did not significantly change. The scores on all the PROs significantly improved from baseline to 12 months. A total of 22 AEs occurred consistent with the known AE profile for infliximab. Conclusions Clinical outcomes among biologic-naive users of infliximab-dyyb improved for UC and were maintained for CD patients. Biologic-naive users of infliximab-dyyb showed significant improvements in PROs. Patients switching from RP infliximab to infliximab-dyyb maintained their clinical outcomes and PROs.