IgA nephropathy. Naifukang is an oral targeted budesonide sustained-release capsule, which is a therapeutic drug for IgA nephropathy, so it needs to be used in the case of IgA nephropathy. Naifukang has been approved by Hainan Provincial Drug Administration and will be used clinically in Hainan Hospital of Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine.