Ultra-proactive therapeutic drug monitoring of infliximab based on point-of-care-testing in inflammatory bowel disease: results of a pragmatic trial.

BACKGROUND With point of care testing (POCT) for infliximab (IFX), ultraproactive therapeutic drug monitoring (TDM) with ad-hoc dose optimisation is possible in patients with inflammatory bowel disease (IBD). AIM To compare the clinical outcomes of an ultraproactive TDM algorithm of IFX based on POCT with reactive TDM in patients with IBD, in a pragmatic clinical trial. METHODS All patients with IBD and maintenance IFX treatment were included between June and August 2018 in two centers. Center A applied an ultra-proactive TDM algorithm incorporating POCT, while center B applied reactive TDM. Primary endpoint was failure of IFX therapy after one year. Secondary endpoints included sustained clinical remission and mucosal remission. RESULTS In total 187 patients (n=115/72 cohort A/B) were included. Cohort A had more TL measurements compared with cohort B (8.8 vs 1/patient/year; p<.0001), leading to a significant higher number of dose optimizations. POCT testing was required in 27% after the first round of ultraproactive TDM and in a mean of 6.3% (SD 1.9) in the subsequent rounds. Ad-hoc extra dosing was needed in 13% of the POCT. After one year, no difference was seen between cohort A and cohort B in IFX failure (19% vs 10%; p=.08), nor in sustained clinical remission (75% vs 83%; p=.17). Mucosal remission was evaluated in 71 patients (38%), and was more frequent in the reactive TDM cohort (p=.02). CONCLUSION Ultraproactive TDM in patients with IBD and maintenance IFX treatment leads to equal clinical outcomes as reactive TDM after one year of follow-up.