Pharmacogenomics enables personalization of drug therapy improving effectiveness and/or safety. Dihydropyrimidine dehydrogenase [DPYD] testing prior to fluoropyrimidine chemotherapy was commissioned by NHS England in response to an update from the Medicines and Healthcare products Regulatory Agency.
A questionnaire developed and approved by the National DPYD Working Group investigated processes of testing, receiving and responding to results. The survey was distributed to Genomics Medicine Service Alliance (GMSA) Clinical Directors and Pharmacy Senior Responsible Officers for dissemination in their geography. Data were collected June-September 2021. All hospitals delivering fluoropyrimidines across the UK were invited to participate.
131/138 (94.9%) organizations reported testing all patients receiving fluoropyrimidines. In England 76.7% of hospitals sent samples to centrally commissioned genomics laboratories. In the devolved nations, 73.9% sent samples to regional genomics laboratories. Multidisciplinary staff including oncologists, independent non-medical prescribers, clinical nurse specialists, screening pharmacists and chemotherapy nurses requested the test, checked and actioned the result. Self-reported turnaround times varied from 10 days.
Through multiprofessional, national collaboration, this is the first report studying the large-scale rollout of a nationally commissioned pharmacogenetic test. Whilst DPYD testing has been successfully implemented, there is a need to standardize and improve end-to-end turnaround times. This has led to the development of a best practice pathway. Critically, GMSAs must build on this implementation to deliver its priorities, in supporting equitable access to future pharmacogenomic testing across a wider cohort of therapies.

© 2025 The Author(s). British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.