The study, conducted at a hospital in Spain from 2015 to 2017, included all 100 patients who were switched to the biosimilar from the reference infliximab when the hospital transitioned to using the lower-cost product.
While it is becoming more common to switch patients with inflammatory bowel disease (IBD) to biosimilar CT-P13 (Inflectra, Remsima) from the reference infliximab (Remicade), long-term follow-up data is lacking. However, in one newly published study from a single-center, researchers reported that, at 2 years, most patients who switched continued on the biosimilar.
The study, conducted at a hospital in Spain from 2015 to 2017, included all 100 patients with moderate to severe Crohn disease (CD) (n = 64) or ulcerative colitis (UC) (n = 36) who were switched to the biosimilar from the reference infliximab when the hospital transitioned to using the lower-cost biosimilar.
The study’s primary end point was to analyze loss of response to infliximab after the switch.
The investigators found that, at 2 years, 72% of patients remained on the biosimilar. In total, 15% discontinued after loss of response, 4% discontinued due to adverse events (AEs), and 8% discontinued due to remission. One patient who achieved remission was switched to a different biologic after developing episcleritis. A total of 22% of patients required dose escalation during the follow-up period.
At the beginning of the study, 78% of patients were in remission. At 12, 18, and 24 months, 69.6%, 69.9%, and 68.5%, respectively, remained in remission. Among those who lost response, there was a median time to discontinuation of 15 months (range, 8-24).
By disease type, at 2 years, 25% of the patients with CD had discontinued (10 for loss of response, 3 because of clinical remission, 2 because of AEs, and 1 because of another medical indication). In the UC group, 33.33% of patients had discontinued at 2 years (5 for loss of response, 5 because of remission, and 2 because of AEs).
A total of 14% of patients experienced AEs, which included skin reactions, asthenia, headache, paresthesia during infusion, and other AEs. Six patients were admitted to the hospital for AEs.
Two patients, both in the CD group, developed antidrug antibodies over 18 months of follow-up. One of these patients achieved remission and discontinued treatment, while the other switched to adalimumab.
According to the authors, this study demonstrates the long-term efficacy of CT-P13 after a switch, and they add that the tranistion to the biosimilar saved the healthcare system €3000 (US $3379.50) per patient per year.
Veloz MFG, Jiménex MB, Delgado TV, et al. Long-term follow up after switching from original infliximab to an infliximab biosimilar: real-world data [published online June 18, 2019]. Therap Adv Gastroenterol. doi: 10.1177/1756284819858052.