Therapeutic Drug Monitoring in Pediatric Inflammatory Bowel Disease: A Nationwide Survey of Anti-TNF Therapy Practices, Attitudes, and Barriers.

Background: Proactive therapeutic drug monitoring (TDM) for tumor necrosis factor alpha antagonist (anti-TNF) therapy in adult inflammatory bowel disease (IBD) remains controversial, with inconsistent findings from clinical trials and meta-analyses. Pediatric societal guidelines endorse the implementation of proactive TDM. However, the integration of TDM into clinical practice by pediatric gastroenterologists has not been characterized. This study was undertaken to delineate the practice patterns, attitudes, and barriers associated with anti-TNF TDM among pediatric gastroenterologists across the United States. Methods: A 28-item questionnaire was developed based on prior adult surveys and current pediatric literature, undergoing 3 rounds of iteration. The survey was comprised of physician demographics, center demographics, TDM practice behavior questions and case-scenarios. The survey was deployed through the ImproveCareNow Learning Health System Network between February and June 2023. Results: Among 380 invitees, 256 (77%) completed the questionnaire. Among respondents, 67% (171) were academic-affiliates, and 55% (140) were female. There was notable variability in the number of patients with IBD seen per practice. All respondents reported using TDM for infliximab, and the majority for adalimumab, and the vast majority utilizing a proactive TDM approach. The principal barriers to TDM implementation were insurance denials, cost, and logistical challenges. More respondents indicated they would initiate TDM during infliximab induction for severe ulcerative colitis than for Crohn's disease. Conclusions: In contrast to the adult literature, most pediatric gastroenterologists report undertaking proactive TDM for anti-TNF agents in IBD management. Precision dosing tools reflective of an individual's pharmacokinetics are desired and need to be further studied.