Non-dialysis-dependent CKD patients (stage 3a-5) with iron deficiency with/without anemia (serum ferritin < 200 μg/L or transferrin saturation = 20% and serum ferritin 200-299 μg/L) were randomized to receive FDI or FCM in a 1:1 ratio. This evidence concerns the gene TF and Iron deficiency anemia.