However, there is some confusion as to what to do with patients who are EPO-resistant despite having apparently "adequate" iron stores based on the values above. Using ferritin as a marker for iron stores has some caveats associated with it, as ferritin is upregulated during inflammation and thus may underestimate the degree of functional iron deficiency in a dialysis patient.
With this mind, the makers of Ferrlicit designed the DRIVE study, in which dialysis patients with a (<11.0g/dL), high ferritin (500-1200 mg/dL), and low transferrin saturation (<25%) were randomized to receive (or not) 1 gram of iv iron administered over dialysis sessions. Both this trial as well as the follow-up DRIVE-II study reported that the iron-treated
group developed higher Tf-sat's and a reduced EPO requirement, suggesting that in some patients an elevated ferritin is not a good marker for iron deficiency. Although the authors report no significant safety issues in the iron-treated group compared with the control group, there is still some concern about the use of continuous iv iron in patients with chronic