Optimizing Treatment, Minimizing Risk: Therapeutic Drug Monitoring in Hematological Malignancies

The therapeutic landscape of hematological malignancies has expanded rapidly, increasing survival but also exposing patients to pharmacokinetic variability and clinically relevant drug-drug interactions. Therapeutic drug monitoring (TDM) offers a pharmacokinetics-informed strategy to individualize dosing, yet its real-world implementation across drug classes and healthcare settings remains insufficiently characterized.

We conducted an international, cross-sectional online survey (December 2023-February 2024) assessing availability, utilization, and clinical impact of TDM in patients with hematological malignancies. Physicians from multiple specialties reported institutional practices, turnaround times, drug-specific monitoring strategies, and treatment modifications based on TDM results.

A total of 209 physicians from 32 countries participated, predominantly from Europe (92%). TDM was widely accessible (97%), mainly performed onsite (79%), and perceived as beneficial by nearly all respondents (99%). Routine TDM was most frequently used for classical agents (methotrexate, cyclosporin A), antifungals, and antibiotics, but substantial interest was reported for targeted therapies, including BCL-2 inhibitors, BCR-ABL tyrosine kinase inhibitors, FLT3 inhibitors, and Bruton tyrosine kinase inhibitors. Treatment was modified based on TDM results by 71% of respondents, with faster turnaround times strongly associated with clinical action. Limited assay availability, delayed reporting, and insufficient clinical evidence were identified as key barriers to broader implementation.

TDM is widely available and perceived as clinically useful in the management of hematological malignancies, frequently informing treatment decisions. While firmly established for classical agents and anti-infectives, clinicians express growing interest in extending TDM to targeted therapies. Optimizing turnaround times, expanding assay availability, and integrating pharmacokinetics-informed dosing into clinical trials may further clarify the role of TDM within precision medicine approaches in hematology.