The goal of this study was to evaluate the effects of the NOX1/4 inhibitor GKT‐137831 (GKT), the PTH‐lowering calcimimetic KP‐2326, and their combination in a slowly progressive rat model of CKD, the male Cy/+ rat, at levels of moderate CKD to prevent end organ manifestations of CKD‐MBD. Here, NOX1 is linked to chronic kidney disease.