There is evidence that drugs such as warfarin (CYP2C9 substrate) and midazolam (CYP3A4 substrate) have altered pharmacokinetics in CKD, although the mechanism for these observations is controversial (Dreisbach et al, 2003; Nolin et al, 2009; Thomson et al, 2015; Tuey et al, 2022). The gene discussed is CYP3A4; the disease is chronic kidney disease.