ABSTRACT
BACKGROUND: efficacy and safety were evaluated after switching to a biosimilar infliximab (CPT-13) in patients with inflammatory bowel disease (IBD). However, few cohort studies compare the pharmacokinetic profiles, immunogenicity, and safety of the reference infliximab (IFX) and CPT-13 in a real clinical setting. OBJECTIVE: to compare the pharmacokinetic profiles and drug survival on the long term of reference IFX and CPT-13 at weeks 54 and 104. A secondary objective was to determine the long-term immunogenicity and safety profile of CPT-13 in patients with IBD in a real clinical setting. METHODS: a retrospective, observational cohort analysis was performed in a single center, including patients with IBD under treatment with reference IFX or CPT-13. Serum drug concentrations were compared to determine if there were any significant differences in pharmacokinetic outcomes between reference IFX and CPT-13 at 26, 54, 78, and 104 weeks. The drug survival of reference IFX and CPT-13 was determined at weeks 54 and 104. RESULTS: one hundred and six patients were included during the study period. Forty-five (42.5 %) patients received CPT-13 and 61 (57.5 %) received reference IFX. A total of 347 serum samples were analyzed and no significant differences were observed between reference IFX and CPT-13. The percentage of patients who achieved serum concentrations within the target therapeutic range was similar in both groups (74.1 % for reference IFX and 72.5 % for CPT-13, p = 0.741). At week 54, withdrawal rates for reference IFX and CPT-13 were 11.5 % and 20.0 %, respectively (p = 0.226), whereas at week 104 they were 26.2 % and 28.9 %, respectively (p = 0.761). CONCLUSION: the pharmacokinetic characteristics and incidence of immunogenicity of CPT-13 in a real clinical setting are comparable to those of the infliximab originator. The two products also have similar long-term drug survival and the same safety profile.
