Loss of efficacy and safety of the switch from infliximab original to infliximab biosimilar (CT-P13) in patients with inflammatory bowel disease

BACKGROUND Infliximab original has changed the natural history of inflammatory bowel diseases (IBD) over the past two decades. However, the recent expiration of its patent has allowed the entry of the first Infliximab biosimilar into the European and Spanish markets. Currently switching drugs data in IBD are limited. AIM To compare the efficacy of infliximab biosimilar, CT-P13, against infliximab original, analyzing the loss of response of both at the 12 mo follow-up in patients with IBD. METHODS An observational study of two cohorts has been conducted. One retrospective cohort that included patients with IBD treated with Infliximab original, and a prospective cohort of patients who were switching from infliximab original to infliximab biosimilar (CT-P13). We had analyzed the overall efficacy and loss of efficacy in patients in remission at the end of one year after treatment with the original drug compared to the results of the year of treatment with the biosimilar. RESULTS 98 patients (CD 67, CU 31) were included in both cohorts. The overall efficacy for infliximab original per year of treatment was 71% vs 68.2% for infliximab biosimilar (P = 0.80). The loss of overall efficacy at 12 mo for infliximab original was 6.6% vs 14.5% for infliximab biosimilar (P = 0.806). The loss of efficacy in patients who were in basal remission was 16.3% for infliximab original is 27.1% for infliximab biosimilar. Adverse events were 9.2% for infliximab original is 11.2% for infliximab biosimilar. CONCLUSION The overall efficacy and loss of treatment response with infliximab biosimilar (CT-P13) is similar to that observed with infliximab original in patients who were switching at the 12 mo follow-up. There is no difference in the rate of adverse events.