Is Routine Monitoring of TNF-α Inhibitor Levels and Antibodies in Pediatric IBD Justified in the Era of Personalized Medicine

Inflammatory bowel disease (IBD) with an onset in childhood is characterized by a more extensive phenotype, a more aggressive clinical course, and a higher risk of long-term complications, including growth retardation, compared to adult-onset disease. While tumor necrosis factor-alpha (TNF-α) inhibitors are the cornerstone of therapy, achieving sustained remission in children is often hindered by unique pharmacokinetic challenges, such as accelerated drug clearance and a higher propensity for immunogenicity. This review explores the evolving role of therapeutic drug monitoring (TDM), specifically the paradigm shift from reactive to proactive strategies. While proactive TDM remains a subject of debate in adult IBD, emerging pediatric data strongly support its routine use to optimize treatment durability and prevent secondary loss of response. Evidence-based target trough concentrations for pediatric patients are critical for achieving mucosal healing: 8–13 µg/mL at week 6 and >5–7 µg/mL during maintenance for infliximab, and >13–14 µg/mL post-induction for adalimumab. Beyond clinical outcomes, this review emphasizes the economic viability of proactive TDM, which has been shown to reduce total healthcare expenditures by 18–30% by minimizing hospitalizations and avoiding premature treatment switches. By integrating pharmacological data with clinical pathways, proactive TDM serves as an essential tool for personalized medicine, ensuring safer and more cost-effective management of pediatric IBD.