Roxadustat induced fetal hemoglobin in anemic CKD patients: a dual-center real-world observational cohort study

Induction of fetal hemoglobin (HbF) expression is a promising therapeutic approach for hemoglobinopathies. HbF is primarily regulated by hypoxia-inducible factor (HIF). Roxadustat, an oral HIF prolyl hydroxylase inhibitor (HIF-PHI), is utilized in the treatment of chronic kidney disease (CKD) patients with anemia. Its capacity to induce HbF has been demonstrated in cell and animal models, but not in humans. In this dual-center, prospective, real-world, non-randomized observational cohort study, we initially enrolled 85 anemic CKD patients receiving distinct anti-anemia treatments. Following post hoc exclusion of participants with insufficient follow-up data, we analyzed the data of 52 patients, comprising those in the oral Roxadustat group (n = 27) and the subcutaneous erythropoiesis-stimulating agent (ESA) group (n = 25). HbF levels were monitored every four weeks by measuring the percentage of HbF-positive red blood cells (F-cells) and mean corpuscular fetal hemoglobin (MCHbF). Roxadustat administration showed progressive elevation of HbF levels, however, the ESA group exhibited only minor nonprogressive HbF fluctuations throughout the observation period. Significant differences in the increase of F-cells percentage and MCHbF between the two groups were observed at week 4 and amplified at week 8 and 12. Only one patient in the Roxadustat group exhibited clinically significant hypothyroidism requiring levothyroxine replacement. Safety monitoring was limited to clinically evident events reported during routine visits; consequently, subclinical abnormalities or mild adverse events were not systematically documented. Our study suggested that Roxadustat has the potential to induce HbF expression in anemic CKD patients. The study was registered retrospectively in the Chinese Clinical Trial Registry (ChiCTR, https://www.chictr.org.cn) under the identifier ChiCTR2500096786 on February 6, 2025.