Effect of ferric citrate hydrate on fibroblast growth factor 23 and platelets in non-dialysis-dependent chronic kidney disease and non-chronic kidney disease patients with iron deficiency anemia

Kyoko Ito; Tadao Akizawa; Kojo Arita; Yuko Mitobe; Norio Komatsu

doi:10.1007/s10157-023-02455-6

Effect of ferric citrate hydrate on fibroblast growth factor 23 and platelets in non-dialysis-dependent chronic kidney disease and non-chronic kidney disease patients with iron deficiency anemia

Clin Exp Nephrol. 2024 Feb 25. doi: 10.1007/s10157-023-02455-6. Online ahead of print.

Authors

Kyoko Ito^{1

2}, Tadao Akizawa³, Kojo Arita⁴, Yuko Mitobe¹, Norio Komatsu⁵

Affiliations

¹ Medical Affairs Department, Torii Pharmaceutical Co., Ltd., 3-4-1, Nihonbashi-Honcho, Chuo-Ku, Tokyo, 103-8439, Japan.
² Doctoral Program in Life Science Innovation (Disease Mechanism), Degree Programs in Comprehensive Human Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8577, Japan.
³ Division of Nephrology, Department of Medicine, Showa University School of Medicine, Namics Shinagawa 301, 4-24-51 Takanawa, Minato-Ku, Tokyo, 108-0074, Japan. akizawa@med.showa-u.ac.jp.
⁴ Clinical Development Department, Pharmaceutical Division, Japan Tobacco Inc., 3-4-1, Nihonbashi-Honcho, Chuo-Ku, Tokyo, 103-0023, Japan.
⁵ Department of Hematology, Juntendo University School of Medicine, 2-1-1, Hongo, Bunkyo-Ku, Tokyo, 113-8421, Japan.

PMID: 38402503
DOI: 10.1007/s10157-023-02455-6

Abstract

Background: Iron deficiency anemia (IDA) increases levels of C-terminal fibroblast growth factor 23 (cFGF23) and platelet count (PLT), each of which is associated with cardiovascular events. Therefore, we hypothesized that iron replacement with ferric citrate hydrate (FC) would decrease cFGF23 levels and PLT in patients with IDA.

Methods: In a randomized, open-label, multicenter, 24-week clinical trial, patients with non-dialysis-dependent chronic kidney disease (CKD) and non-CKD complicated by IDA (8.0 ≤ hemoglobin < 11.0 g/dL; and serum ferritin < 50 ng/mL [CKD]; < 12 ng/mL [non-CKD]) were randomized 1:1 to FC-low (500 mg: approximately 120 mg elemental iron/day) or FC-high (1000 mg: approximately 240 mg elemental iron/day). If sufficient iron replacement had been achieved after week 8, further treatment was discontinued.

Results: Seventy-three patients were allocated to FC-low (CKD n = 21, non-CKD n = 15) and FC-high (CKD n = 21, non-CKD n = 16). Regardless of CKD status, FC increased serum ferritin and transferrin saturation, did not change intact FGF23 or serum phosphorus, but decreased cFGF23. In FC-low group, median changes in cFGF23 from baseline to week 8 were -58.00 RU/mL in CKD and -725.00 RU/mL in non-CKD; in FC-high group, the median changes were -66.00 RU/mL in CKD and -649.50 RU/mL in non-CKD. By week 8, FC treatment normalized PLT in all patients with high PLT at baseline (>35.2 × 10⁴/µL; FC-low: 1 CKD, 8 non-CKD; FC-high: 3 CKD, 8 non-CKD).

Conclusion: Regardless of CKD status, iron replacement with FC decreased elevated cFGF23 levels and normalized elevated PLT in patients with IDA.

Clinical trial registration number: jRCT2080223943.

Keywords: Chronic kidney disease (CKD); Ferric citrate hydrate; Fibroblast growth factor 23 (FGF23); Iron deficiency anemia (IDA); Platelet count (PLT).