The purpose of this study is to determine whether Dialysate containing soluble iron (Soluble Ferric Pyrophosphate) is safe and effective in maintaining physiological iron levels during chronic hemodialysis.

The study was designed to evaluate the efficacy of SFP-containing dialysate solution in maintaining physiological iron levels during chronic hemodialysis, as measured by the primary endpoint of the percent of patients whose Hemoglobin (Hgb) decreased by at least 1.0 gram/ deciliter (g/dL) from baseline. The efficacy and safety findings are to be used to determine the optimal concentration of SFP needed to safely maintain iron levels, compensating for iron losses during chronic hemodialysis.

Selected Inclusion Criteria:

1. Adult subject ≥ 18 years of age undergoing chronic hemodialysis for end-stage renal disease (ESRD) three times a week
2. Hemoglobin (Hgb) values on two successive screening/baseline measures immediately prior to the start of the study averaging 10.1 to 11.5 grams/ deciliter (g/dL), inclusive
3. Transferrin Saturation (TSAT) values that average 20% or more, but not exceeding 35%, prior to dialysis measured during the screening period
4. Ferritin values that average 200 to 800 micrograms/ liter (µg/L), inclusive, measured during the screening period. An average ferritin above 800 µg/L but no greater than 1200 µg/L is allowed if the average TSAT is 20% to no greater than 25%.
5. Except for vascular access surgery, subject has no hospitalization in previous three months for a significant illness that, in the opinion of the Investigator, confers a significant risk of hospitalization during the course of the study. No blood transfusions within the last 4 weeks are allowed.
6. Subject has an adequate dialyzer blood flow rate that is acceptable to the Principal Investigator

Exclusion Criteria:

1. Hemoglobin (Hgb) values on two successive baseline/screening measurements that average ≥ 11.6g/dL
2. Subject with a current malignancy involving a site other than skin
3. Subject with a history of drug or alcohol abuse within the last six months
4. Subject believed to be unable to complete the entire study (e.g., due to a concurrent disease, life expectancy of less than a year)
5. Subject who the Principal Investigator considers will be placed at increased risk by the study procedures
6. Subject requiring hemodialysis more than 3 times per week on a regular basis.
7. Subject who is unable to discontinue oral iron or intravenous iron supplements for the duration of the study
8. Subject who is pregnant
9. Subject considered incompetent to give an informed consent
10. Subject with a positive test for Hepatitis B Surface Antigen within the past 30 days or during screening
11. Subject with known HIV infection (if this is not known, no HIV testing will be performed)
12. Subject with cirrhosis of the liver based on histological criteria or clinical criteria (presence of ascites, esophageal varices, spider nevi, or history of hepatic encephalopathy). Subject with hepatitis C, in the absence of cirrhosis, is not excluded from participation in the study if ALT and AST levels are below 2 times the upper limit of normal consistently during the 2 months preceding enrollment
13. Subject with active tuberculosis, fungal, viral, or parasitic infection
14. Subject with active bacterial infection requiring antibiotic therapy
15. Subject with pre-dialysis Corrected Q-wave to T-wave (QTc) interval ≥ 470 milliseconds (ms)
16. Subject with a history of hypokalemia, decompensated heart failure, or family history of Long QT Syndrome that in the Investigator's judgment poses a risk for Torsades de Pointe during the study
17. Subject using concomitant medications known to prolong QT/QTc interval (See Appendix I, TABLE A)
18. Subject receiving more than 60,000 units or 120 micrograms of erythropoietin (Epogen®, Procrit®, or Aranesp®) per week
19. Subject has participated in another clinical trial within 30 days of signing Informed Consent