Background CT-P13 was developed as a biosimilar product to infliximab (Remicade®), a chimeric monoclonal antibody approved in the European Union in 1999 for the treatment of rheumatoid arthritis (RA), ankylosing spondylitis (AS), Crohn’s disease, ulcerative colitis, psoriasis, and psoriatic arthritis.
Objectives To compare the pharmacokinetic (PK) profile of CT-P13 with that of infliximab at steady state in terms of area under the concentration-time curve over a dosing interval (AUCτ) and observed maximum serum concentration (Cmax,ss), and evaluate the efficacy and overall safety of both treatments in patients with AS.
Methods Two hundred fifty patients with active AS were randomized 1:1 to receive either CT-P13 or infliximab (5 mg/kg, 2-hour IV infusion per dose) at weeks 0, 2, and 6 (dose-loading phase) and at weeks 14, 22, and 30 (maintenance phase). Ratios of geometric means of primary PK parameters (AUCτ and Cmax,ss) from the 2 treatment arms between weeks 22 and 30 were subjected to ANCOVA analysis at 90% confidence intervals (CIs). Efficacy measures (including ASAS20 and ASAS40), and safety parameters (including the incidence of adverse events [AEs]) were also evaluated. This report presents PK, efficacy, and safety results up to week 30 (as approved by the European Medicines Agency).
Results The mean (% CV) AUCτ was 34855.45 (34.3%) μg-h/mL and 34688.71 (45.4%) μg-h/mL in the CT-P13 and infliximab arms, respectively. The mean (% CV) Cmax,ss was 153.52 (27.6%) μg/mL and 150.39 (26.9%) μg/mL in the CT-P13 and infliximab arms, respectively. The ratio (%) between the geometric means of the AUCτ and Cmax,ss values in the CT-P13 and infliximab arms were 104.1% (90% CI 93.9% to 115.4%) and 101.5% (90% CI 94.6% to 108.9%), respectively, between weeks 22 and 30, indicating PK equivalence in terms of AUCτ and Cmax,ss. Secondary parameters at week 30 were also comparable, including ASAS20 and ASAS40 response rates (70.5% for CT-P13 vs 72.4% for infliximab and 51.8% vs 47.4%, respectively). AEs considered by the investigators to be related to study treatment were reported in 57 (44.5%) patients and 58 (47.5%) patients in the CT-P13 and infliximab arms, respectively. Related AEs due to infection were reported for 24/128 (18.8%) patients and 22/122 (18.0%) patients in the CT-P13 and infliximab treatment groups, respectively. AEs due to infusion reactions considered related to study drug were reported in 5 patients in the CT-P13 arm, and 6 patients in the infliximab arm. Tuberculosis was reported in 2 patients in the CT-P13 arm and in 1 patient in the infliximab arm.
Conclusions CT-P13 and infliximab are equivalent in terms of AUCτ and Cmax,ss in patients with AS. In addition, CT-P13 was well tolerated, with an efficacy and safety profile comparable to that of infliximab up to week 30.
Disclosure of Interest W. Park: None Declared, P. Hrycaj: None Declared, V. Kovalenko: None Declared, P. Miranda: None Declared, S. Gutierrez-Ureña: None Declared, Y. Lee: None Declared, M. Lim: None Declared, C. Ahn: None Declared, H. Kim Employee of: Celltrion, D. Yoo: None Declared, J. Braun: None Declared