Effect of oral ferric citrate on serum phosphorus in hemodialysis patients: multicenter, randomized, double-blind, placebo-controlled study

Background: Hyperphosphatemia is a common complication in dialysis patients that can be treated by oral phosphate binders. We investigated the efficacy and safety of oral ferric citrate as a phosphate binder for Taiwanese patients with end stage renal disease and with hyperphosphatemia who were undergoing hemodialysis.

Methods: This was a prospective, double-blind, placebo-controlled, randomized trial carried out in 5 hospitals in Taiwan. Ferric citrate (4 or 6 g/day) or placebo was administered for 56 days. Serum calcium, phosphorous levels, calcium × phosphorus product, serum ferritin level, transferrin saturation, and adverse events were recorded.

Results: A total of 166 patients completed the trial. The placebo group had relatively constant serum data. Serum phosphorus declined significantly in the 6 g/day group (p < 0.05 for 4 and 8 weeks) and the 4 g/day group (p < 0.05 for 4 and 8 weeks). There were similar changes in the calcium × phosphorus product. The serum ferritin level increased significantly in the 6 g/day group (p < 0.05) and the 4 g/day group (p < 0.05). There were similar changes in transferrin saturation. Most adverse events were mild to moderate and were comparable among the three groups.

Conclusions: A 56-day treatment with ferric citrate effectively controlled hyperphosphatemia and was well tolerated in maintenance hemodialysis patients. There were also moderate increases in serum ferritin and transferrin saturation.