BackgroundThis planned interim analysis of a mandatory post-marketing surveillance study in Japan evaluated the safety and effectiveness of roxadustat, the first approved hypoxia-inducible factor prolyl hydroxylase inhibitor in the world, in real-world clinical use.Research design and methodsThis prospective observational study has a planned 104-week observation period. We report data obtained through 16 December 2023, as a planned interim analysis. Adverse drug reactions (ADRs), mean hemoglobin level change from baseline to 12 weeks of roxadustat treatment, and subgroup analyses stratified by either baseline C-reactive protein or albumin levels were reported.ResultsOverall, 2084 patients were treated with roxadustat (total patient-years of exposure: 1579.2). In the non-dialysis-dependent (NDD) group (n = 1075), ADRs and serious ADRs occurred in 209 (19.4%) and 109 (10.1%) patients, respectively. In patients receiving hemodialysis (HD; n = 856), ADRs and serious ADRs occurred in 224 (26.2%) and 142 (16.6%) patients, respectively. In patients receiving peritoneal dialysis (PD; n = 146), ADRs and serious ADRs occurred in 46 (31.5%) and 26 (17.8%) patients, respectively. Mean hemoglobin levels reached target levels at 12 weeks in most patients (NDD: 54.6%; HD: 56.3%; PD: 45.4%).ConclusionsRoxadustat safety was demonstrated in real-world clinical settings. No new safety concerns were identified.Trial Registration: NCT04408820ConclusionsRoxadustat safety was demonstrated in real-world clinical settings. No new safety concerns were identified.Trial Registration: NCT04408820