A recent analysis of clinical studies in patients with chronic kidney disease (CKD) involving 18 known substrates of OAT1 (SLC22A6) and OAT3 (SLC22A8) revealed that the active secretion of most drugs deteriorated faster than renal filtration in CKD, which meant that the secretory clearance normalized to GFR was reduced in CKD patients in comparison with subjects with normal renal function. This evidence concerns the gene SLC22A6 and chronic kidney disease.