Direct Bilirubin Affects Roxadustat Efficacy for Anemia in Patients on Dialysis

Background: Roxadustat, an orally active hypoxia-inducible factor prolyl hydroxylase inhibitor, shows promise in treating anemia associated with chronic kidney disease. This study aims to identify factors affecting the efficacy of roxadustat. Methods: We conducted a single-center retrospective study involving patients undergoing regular hemodialysis or peritoneal dialysis and treated with roxadustat. Patients were categorized into invalid, effective, and markedly effective groups based on changes in hemoglobin levels after four weeks of treatment. Demographic information, medications, and laboratory parameters were compared among these groups. Results: Linear correlations were observed between the initial efficacy of roxadustat and levels of direct bilirubin and neutrophil counts. The receiver operating characteristic curve, using a direct bilirubin cut-off value of 3.25 µmol/L and a neutrophil cut-off value of 3.4 g/L, revealed that patients with direct bilirubin <3.25 µmol/L had a superior response to roxadustat during the 12-week follow-up. Neutrophil counts influenced roxadustat efficacy at the 4-week mark but lost significance by the 12th week. Patients in the invalid group consistently exhibited lower hemoglobin change levels at the 8th and 12th weeks compared to those in the effective and markedly effective groups. Conclusion: Direct bilirubin and neutrophil counts exhibited a negative correlation with hemoglobin change levels in dialysis patients. At the 12-week mark, direct bilirubin, but not neutrophil counts, significantly impacted roxadustat efficacy. Patients with a favorable initial response demonstrated higher hemoglobin change levels during follow-up, irrespective of the roxadustat dosage, compared to those with a poor initial response.