Real-World Applications of Pharmacogenomics in Paediatrics

Pharmacogenomics (PGx) is the study of how interindividual genetic variability affects drug response. Clinically, PGx testing may be used to enhance individualised pharmacotherapy, minimising adverse drug reactions and improving treatment outcomes. This review explores the clinical application of PGx testing in paediatrics, particularly in emphasising oncology, psychiatry and other supportive therapeutic areas due to its primacy of use in these fields. In paediatric oncology, TPMT and NUDT15-guided pharmacotherapy may significantly reduce drug toxicity without increasing symptomatic relapse rates. The clinical utility of PGx testing extends to inflammatory bowel disease, antimicrobial stewardship, analgesic use and psychotropic prescribing, where case studies provided in this review will demonstrate how tailored approaches may improve clinical outcomes. Despite these advancements, PGx implementation faces systemic barriers, limited clinician training, complex reporting formats, and low public awareness inhibiting the uptake of PGx use into everyday clinical care. We provide future directions to these systemic barriers, including standardised reporting, professional education initiatives and multidisciplinary collaborations, which are all helping to address these current challenges. Furthermore, access and reimbursement constraints also hinder individual adoption. However, health economic analyses and the decreasing costs of genetic testing offer hope for expanded accessibility. Enhanced data governance and public education are also required to overcome privacy concerns and foster acceptance. Continued investment in paediatric-specific PGx research and age-specific guidelines is vital in bridging knowledge gaps and addressing developmental differences in drug metabolism.