M G Ward1,2,3, B Warner1, N Unsworth4, S-W Chuah5, C Brownclarke1, S Shieh5, M Parkes5, J D Sanderson1, Z Arkir4, J Reynolds3, P R Gibson2,3, P M Irving1. 1. Department of Gastroenterology, Guy's and St. Thomas' NHS Foundation Trust, London, UK. 2. Department of Gastroenterology, Alfred Hospital, Melbourne, Victoria, Australia. 3. Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria, Australia. 4. Reference Chemistry, Viapath, St. Thomas' Hospital, London, UK. 5. Department of Medicine, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK.
Abstract
BACKGROUND: Discriminative drug level thresholds for disease activity endpoints in patients with Crohn's disease. have been consistently demonstrated with infliximab, but not adalimumab. AIMS: To identify threshold concentrations for infliximab and adalimumab in Crohn's disease according to different disease endpoints, and factors that influence drug levels. METHODS: We performed a cross-sectional service evaluation of patients receiving maintenance infliximab or adalimumab for Crohn's disease. Serum drug levels were at trough for infliximab and at any time point for adalimumab. Endpoints included Harvey-Bradshaw index, C-reactive protein and faecal calprotectin. 6-tioguanine nucleotide (TGN) concentrations were measured in patients treated with thiopurines. RESULTS: A total of 191 patients (96 infliximab, 95 adalimumab) were included. Differences in infliximab levels were observed for clinical (P=.081) and biochemical remission (P=.003) and faecal calprotectin normalisation (P<.0001) with corresponding thresholds identified on ROC analysis of 1.5, 3.4 and 5.7 μg/mL. Adalimumab levels were similar between active disease and remission regardless of the endpoint assessed. Modelling identified that higher infliximab dose, body mass index and colonic disease independently accounted for 31% of the variation in infliximab levels, and weekly dosing, albumin and weight accounted for 23% of variation in adalimumab levels. TGN levels did not correlate with drug levels. CONCLUSIONS: Infliximab drug levels are associated with the depth of response/remission in patients with Crohn's disease, but no such relationship was observed for adalimumab. More data are needed to explain the variation in drug levels.
BACKGROUND: Discriminative drug level thresholds for disease activity endpoints in patients with Crohn's disease. have been consistently demonstrated with infliximab, but not adalimumab. AIMS: To identify threshold concentrations for infliximab and adalimumab in Crohn's disease according to different disease endpoints, and factors that influence drug levels. METHODS: We performed a cross-sectional service evaluation of patients receiving maintenance infliximab or adalimumab for Crohn's disease. Serum drug levels were at trough for infliximab and at any time point for adalimumab. Endpoints included Harvey-Bradshaw index, C-reactive protein and faecal calprotectin. 6-tioguanine nucleotide (TGN) concentrations were measured in patients treated with thiopurines. RESULTS: A total of 191 patients (96 infliximab, 95 adalimumab) were included. Differences in infliximab levels were observed for clinical (P=.081) and biochemical remission (P=.003) and faecal calprotectin normalisation (P<.0001) with corresponding thresholds identified on ROC analysis of 1.5, 3.4 and 5.7 μg/mL. Adalimumab levels were similar between active disease and remission regardless of the endpoint assessed. Modelling identified that higher infliximab dose, body mass index and colonic disease independently accounted for 31% of the variation in infliximab levels, and weekly dosing, albumin and weight accounted for 23% of variation in adalimumab levels. TGN levels did not correlate with drug levels. CONCLUSIONS:Infliximab drug levels are associated with the depth of response/remission in patients with Crohn's disease, but no such relationship was observed for adalimumab. More data are needed to explain the variation in drug levels.
Authors: Konstantinos Papamichael; Adam S Cheifetz; Gil Y Melmed; Peter M Irving; Niels Vande Casteele; Patricia L Kozuch; Laura E Raffals; Leonard Baidoo; Brian Bressler; Shane M Devlin; Jennifer Jones; Gilaad G Kaplan; Miles P Sparrow; Fernando S Velayos; Thomas Ullman; Corey A Siegel Journal: Clin Gastroenterol Hepatol Date: 2019-03-27 Impact factor: 11.382
Authors: Konstantinos Papamichael; Anna Juncadella; Danny Wong; Shana Rakowsky; Lindsey A Sattler; James P Campbell; Byron P Vaughn; Adam S Cheifetz Journal: J Crohns Colitis Date: 2019-08-14 Impact factor: 9.071