Lay summary
People respond differently to medications, and one key reason is genetic differences in drug transporters - proteins that help move drugs into and out of cells. Our research focuses on the genetic variants on two transporters that are found only in Māori and Pacific peoples. These unique variants may change how common medications like metformin (for diabetes) and oxaliplatin (for cancer) work, potentially leading to treatment failure or harmful side effects. We have already shown in pre-clinical model that one variant reduces metformin’s effectiveness, which could explain why some patients don’t benefit from the drug. We will now study how this and similar variants affect drug response in humans, and test thirty commonly used (PHARMAC-approved) medications in Aotearoa to see if changes in transporter function impact their safety or effectiveness. This research will support more personalised and safer prescribing for Māori and Pacific patients, and help ensure medicines work better for everyone in Aotearoa.