Ferric citrate for iron deficiency anemia in non-dialysis dependent chronic kidney disease: a randomized phase III study

Background: Ferric citrate (FC) can replenish iron stores in patients with non-dialysis-dependent chronic kidney disease (NDD-CKD) and iron deficiency anemia (IDA). This study evaluated the efficacy and safety of FC (PBF-1681, Panion & BF Biotech Inc.) in NDD-CKD Taiwanese patients. Methods: In this double-blind, placebo-controlled, randomized Phase III trial, patients were assigned 1:1 to receive either PBF-1681 or placebo for 16 weeks, followed by an 8-week open-label extension in which all participants received PBF-1681. The starting dose was 2 g/day, with an additional 2 g/day titration based on hemoglobin and serum phosphate levels. Results: A total of 141 patients were randomized to either the PBF-1681 or placebo group. Of these, 114 completed the 16-week randomized period and 106 completed the full 24-week study. The primary endpoint was met, with the PBF-1681 group showing a significantly greater increase in hemoglobin from baseline to Week 16 compared to the placebo group (intergroup difference: 0.62 ± 0.15 g/dL, p < 0.0001). Significant between-group differences were also observed for all secondary and several exploratory endpoints, including the proportion with hemoglobin increase ≥1.0 g/dL, a sustained effect (hemoglobin increase of ≥0.75 g/dL from baseline over any 4-week time period), and changes in iron-related parameters, serum phosphate, intact parathyroid hormone, and fibroblast growth factor 23 levels (all p < 0.05). The most common treatment-related adverse events were gastrointestinal disorders, including diarrhea, discolored feces, abdominal discomfort, constipation, and abdominal pain. Conclusion: PBF-1681 was effective for treating IDA in Taiwanese NDD-CKD patients and had a favorable safety profile.