Efficacy of biosimilar infliximab CT-P13 among inpatients with severe steroid-refractory colitis

Introduction: In this study, we evaluate the efficacy and safety of the biosimilar infliximab, CT-P13, in the treatment of inpatients with severe steroid-refractory colitis. Methods: A retrospective cohort study of adult colitis patients (UC or isolated Crohn’s colitis) admitted to the University of Chicago inflammatory bowel disease inpatient service between January 2018 and December 2018 for management of severe colitis refractory to IV steroids who received CT-P13 were included in the study. Patients diagnosed with active small bowel Crohn’s disease were excluded. CT-P13 was given as a single infusion of 5 to 10 mg/kg. A comprehensive review of their electronic medical records was performed, and demographic, clinical, laboratory, and endoscopic data were extracted. The primary endpoint was colectomy-free survival. Results: Twenty-one patients with severe steroid-resistant colitis were included. Twelve patients had ulcerative colitis, seven patients had a diagnosis of indeterminate colitis, and two patients had a diagnosis of Crohn’s colitis. The median age was 32.2 years. The median disease duration was 4.3 years, and the median follow-up time was 5.9 months. Patients had a median CRP of 23. All patients had moderate to severe disease on endoscopy. Colectomy-free survival was 76% at 3 months and 70% at 6 months. No severe adverse events were reported in this patient cohort. Conclusion: A significant proportion of patients with severe colitis failing IV steroids responded to induction therapy with CT-P13. Colectomy-free survival rates were similar to previous randomized trials using originator infliximab as induction therapy in severe steroid-refractory colitis.