Ferric Citrate in Managing Serum Phosphorus and Iron Deficiency in Anemic Chronic Kidney Disease (CKD) Subjects Not on Dialysis

This is a randomized, double-blind, placebo-controlled, three-period, multi-center clinical
trial. Following a Screening and Qualification Period and a two-week Washout Period (for
those subjects entering the study on a phosphate binder), eligible subjects will be
randomized in a 1:1 ratio to receive either KRX-0502 (ferric citrate) or placebo for up to
approximately 12 weeks. The purpose of this study is to determine if KRX-0502 (ferric
citrate) is a safe and effective treatment for the management of serum phosphorus levels and
iron deficiency in anemic CKD subjects not on dialysis.

Inclusion Criteria:

- Stage III to V Chronic Kidney Disease

- Serum Phosphorus 4.0-6.0 mg/dL prior to Randomization

- Ferritin 300 ng/mL or less

- Transferrin Saturation (TSAT) 30% or less

- Hemoglobin >9.0 and <12.0 g/dL

- Must consume a minimum of 2 meals per day

Exclusion Criteria:

- Parathyroidectomy within 24 weeks of study

- gastrointestinal bleed or inflammatory bowel disease within 12 weeks of study

- Requirement for dialysis or kidney injury within 8 weeks of study

- Absolute requirement for oral iron, intravenous iron, Erythropoiesis-Stimulating
Agent, blood transfusions, and Sensipar during the study

- Absolute requirement for calcium-, magnesium-, or aluminum-containing drugs with meals

- Absolute requirement for vitamin C, niacin, or nicotinamide outside of multivitamins

- History of hemochromatosis

- Allergy to iron products

- History of malignancy in last 5 years