The first monoclonal antibody biosimilar to be used in clinical practice is the tumour necrosis factor-alpha inhibitor Remsima® (CT-P13). The drug is approved for all indications as the originator infliximab (Remicade®) although clinical efficacy has been demonstrated only in rheumatic diseases. Since the fall of 2013, Remsima® has been available in Norway and from January 2014, it has been the drug of choice when initiating biological treatment in biologics naïve patients with inflammatory bowel disease (IBD). However, many gastroenterologists have been greatly concerned about the extrapolation of indication. Switching between Remsima® and the innovator product is another issue that has been discussed. Key Messages: Good efficacy, tolerability and safety were demonstrated in a prospective observational study of IBD patients with moderate to severe disease activity. After 14 weeks of treatment there was a significant reduction in the Harvey Bradshaw index in patients with Crohns disease (CD) and reduction in the partial Mayo score and simple clinical colitis activity index in patients with ulcerative colitis. In both patient groups, there was also a significant reduction in fecal calprotectin and C-reactive protein (CRP). In another observational study, IBD patients on maintenance treatment with Remicade® were switched to Remsima®. By comparing values before and after switch, no changes in activity indices, CRP or calprotectin were observed. However, a significant increase in infliximab trough levels was shown in the CD group. No unexpected adverse events occurred after switching.
Based on our experience in Norway, Remsima® seems to be efficacious and well tolerated in IBD. The increasing use of Remsima® in clinical practice has also contributed to significant cost savings on the health budget. Results from the NOR-SWITCH study will be available during 2016 and will hopefully contribute to answer some of the important questions that have been raised following the introduction of biosimilars as a treatment option for IBD and other immune-mediated inflammatory diseases.