Efficacy and safety of single high-dose intravenous ferric carboxymaltose in patients undergoing hemodialysis: a multicenter, single-arm, open-label, clinical trial

BACKGROUND: Iron-deficiency anemia is common in patients undergoing hemodialysis, and intravenous iron therapy is often preferred because oral iron is poorly tolerated and less effective. Ferric caboxymaltose, a high-dose intravenous iron formulation, has recently become available in Japan. However, evidence regarding its efficacy and safety in hemodialysis patients remains limited. Therefore, this study investigated the efficacy and safety of a single intravenous administration of ferric carboxymaltose containing 500 mg of iron in Japanese patients undergoing hemodialysis. METHODS: A 12-week, multicenter, prospective, open-label, single-arm trial was conducted, enrolling 30 Japanese patients undergoing hemodialysis with hemoglobin < 10 g/dL and iron-deficiency (serum ferritin < 100 ng/mL or transferrin saturation [TSAT] < 20%). Hemoglobin, iron-related parameters (serum ferritin, TSAT, 8-hydroxydeoxyguanosine [8-OHdG], hepcidin, intact fibroblast growth factor 23 [FGF-23], and phosphate), and quality of life (Short Form-36 Health Survey [SF-36] and EuroQol 5-Dimension 5-Level) were assessed at baseline and at weeks 1, 2, 4, 8, and 12. The primary endpoint was the change in hemoglobin level from baseline to week 4, assessed using a one-sample t-test against a threshold of 0.5 g/dL. Secondary outcomes included longitudinal changes in hemoglobin, iron-related parameters, and quality of life from baseline to each post-treatment time point, analyzed using a linear mixed-effects model. The occurrence of adverse events was observed over 12 weeks. RESULTS: The mean hemoglobin levels significantly increased by + 0.50 g/dL (95% confidence interval: 0.18-0.82, P = 0.003) from baseline to week 4, and the increase was maintained through week 12. All iron-related parameters peaked by week 2 and subsequently declined; however, serum ferritin levels remained significantly elevated at week 12. SF-36 vitality, general health and mental health scores increased significantly at 4 weeks compared with baseline. No serious adverse events were observed, although one case of arteriovenous fistula occlusion occurred. CONCLUSIONS: Single intravenous iron therapy with ferric carboxymaltose containing 500 mg of iron effectively increased hemoglobin levels without serious adverse events. Further long-term clinical trials are warranted to confirm the efficacy and safety of periodic ferric carboxymaltose therapy in patients undergoing hemodialysis. TRIAL REGISTRATION: This study was prospectively registered with the Japan Registry of Clinical Trials on 23 May, 2023 (registration number jRCTs051230025).