NHS Wales spent £1.2 billion on medicines in 2019-20. While their benefits are substantial, in terms of preventing, managing and curing diseases, improving patients’ quality of life and survival chances, not all medicines are effective all the time. Medicines can also cause side effects (adverse drug reactions) which can be severe and costly to manage. Information on genetic variants in an individual can be used to predict the likelihood that a particular medicine will be effective or cause unintended harm through an adverse reaction.Pharmacogenomics is the study of how genetic variation between individuals affects their response to medications. The use of pharmacogenomic testing in clinical practice informs the choice and dose of medicines. This ensures individuals receive the most effective treatment, while minimising the risk of adverse drug reactions.
Pharmacogenomics in Practice
In 2020, Wales became the first UK nation to routinely provide all cancer patients receiving certain types of chemotherapy with DPYD screening to identify their risk of severe side effects and help prevent these from occurring. An estimated 10% of patients prescribed
fluoropyrimidine drugs, which are widely used for the treatment of cancer, can develop severe, sometimes life-threatening side effects. These toxicities can be triggered by genetic variations in DPYD, the gene that encodes for the enzyme which helps to metabolise (break down) the fluoropyrimidines. Low levels of the DPD enzyme –predicted by the genetic test– can result in a build-up of these chemotherapy drugs, making the side effects more severe and occasionally fatal.
What is the NPGG?
The National Pharmacogenomics Group (NPGG) was established in 2022 following endorsement of a white paper entitled Pharmacogenetics in Wales, by the All Wales Medicines Strategy Group (AWMSG) and the Genomics Partnership Wales (GPW) programme board. The paper described the ambition that NHS Wales should establish
a national pharmacogenomics service, aligned with the Welsh Government’s Genomics Delivery Plan for Wales. The aim of the NPGG is to ensure that there is a multidisciplinary, coordinated national approach with defined clinical input to the development and introduction of pharmacogenomic services within Wales. The membership and terms of reference for the NPGG are available here.