A RANDOMISED, DOUBLE-BLIND, PARALLEL-GROUP, PHASE 1 STUDY COMPARING THE PHARMACOKINETICS, SAFETY AND EFFICACY OF CT-P13 AND INFLIXIMAB IN PATIENTS WITH ACTIVE ANKYLOSING SPONDYLITIS: 54 WEEK RESULTS FROM THE PLANETAS STUDY

Background: CT-P13 is a biosimilar product of infliximab (INX). Data up to week 30 has been reported at EULAR 2012. Objectives: To assess the PK, efficacy and safety of CT-P13 in patients with active AS up to week 54 and to compare this with INX, also in relation to the formation of anti-drug antibodies (ADAs). Methods: Patients with active AS (1984 modified NY criteria) were randomised (1:1) to receive either CT-P13 (5mg/kg) or INX (5mg/kg) at weeks 0, 2, 6 and then every 8 weeks up to week 54. Results: Of 250 patients randomised at baseline, 213 patients were treated up to week 54. Cmax of CT-P13 and INX were shown to be equivalent, since 90% CIs for the ratio of geometric means were within 80–125% at all doses (CT-P13, 128.1µg/mL–172.2µg/mL; INX, 123.0µg/mL–176.7µg/mL). At week 54, the proportion of patients testing positive for ADAs was comparable between CT-P13 and INX (22.9% [25/109] vs 26.7% [28/105]). ADAs had similar effects on PKs in both groups. Patients with negative ADA results had higher Cmax values (CT-P13, 134.5µg/mL–177.2µg/mL; INX, 131.9µg/mL–177.4µg/mL) compared with patients with positive results (CT-P13, 101.8µg/mL–160.4µg/mL; INX, 104.0µg/mL–175.2µg/mL). At week 54, ASAS40 and ASAS partial remission were comparable between groups (CT-P13, 54.7% and 19.8%; INX, 49.1% and 17.6%, respectively). More patients with negative ADA results achieved ASAS40 responses (CT-P13, 61.0%; IFX, 54.7%) compared with patients with positive results (CT-P13, 37.9%; IFX, 36.4%). The safety profiles of CT-P13 and INX were also comparable (table). Active tuberculosis (TB) was reported in 3 patients (CT-P13, 2; INX, 1) and there were no malignancies. Conclusions: CT-P13 has similar PK values and a clinical efficacy comparable to INX up to week 54. CT-P13 was well tolerated with a safety profile comparable to that of INX up to 54 weeks. ADAs seem to diminish the clinical response to both agents in some patients. References: 1.Park W et al. A randomised, double-blind, phase 1 study demonstrates equivalence in pharmacokinetics, safety and efficacy of CT-P13 and infliximab in patients with ankylosing spondylitis. Ann Rheum Dis 2012;71(Suppl 3):111. Disclosure of Interest: W. Park Consultant for: CELLTRION Inc., J. Jaworski Grant/research support from: CELLTRION Inc., J. Brzezicki Grant/research support from: CELLTRION Inc., A. Gnylorybov Grant/research support from: CELLTRION Inc., V. Kadinov Grant/research support from: CELLTRION Inc., I. Goecke Sariego Grant/research support from: CELLTRION Inc., C. Abud-Mendoza Grant/research support from: CELLTRION Inc., W. J. Otero Escalante Grant/research support from: CELLTRION Inc., S. W. Kang Grant/research support from: CELLTRION Inc., D. Andersone Grant/research support from: CELLTRION Inc., F. Blanco Grant/research support from: CELLTRION Inc., D. H. Yoo Consultant for: CELLTRION Inc., C. Ahn Consultant for: CELLTRION Inc., Speakers bureau: CELLTRION Inc., H. U. Kim Employee of: CELLTRION Inc., J. Braun Consultant for: CELLTRION Inc., Speakers bureau: CELLTRION Inc.Citation: , volume 72, supplement s3, year 2013, page Session: Poster Tour: Management of SpA 2 ( )