Long-term follow up after switching from original infliximab to an infliximab biosimilar: real-world data.

Abstract

Several studies have reported positive efficacy outcomes for patients with inflammatory bowel disease treated with CT-P13, an infliximab biosimilar. Data from follow-up periods longer than 1 year are still scarce. Here, we assessed the long-term efficacy data, loss of response and safety after switching from infliximab to CT-P13 in patients with inflammatory bowel disease. This was a prospective single-center observational study involving patients with moderate-to-severe Crohn's disease and ulcerative colitis switched from infliximab to CT-P13 treatment and reviewed up to 24 months. Efficacy and loss of response were measured using the Harvey-Bradshaw (HB) index and partial Mayo score for patients with Crohn's disease and ulcerative colitis respectively. C-reactive protein, infliximab drug levels, adverse events and antidrug antibodies were also monitored throughout the study. A total of 64 patients with Crohn's disease and 36 patients with ulcerative colitis were included. Most of them (72%) remained on CT-P13. Overall, 28% of patients discontinued the therapy due to loss of response, adverse events or long-lasting clinical remission. Remission at 18 and 24 months occurred in 69.9% and 68.5% of patients, respectively. Dose increase was performed in 22% of patients, with remission being reached in 60% of them. HB index, partial Mayo score, C-reactive protein and infliximab drug levels did not show significant changes. Serious adverse events were reported in 14% of patients. Overall, two patients developed low levels of antidrug antibodies. Most of the patients switching from original infliximab were maintained on CT-P13 at 2 years of follow up with a good profile of efficacy and safety.