The present invention relates to IRNA such as dsRNA composition targeting complement factor B (CFB) gene, complement component C3 gene and complement component C9 gene, and the use of such IRNA such as dsRNA composition to inhibit the expression of CFB, C9, and / or C3 and to treat complement component related diseases such as paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome Methods of subjects.本發明涉及靶向補體因子B(CFB)基因、補體成分C3基因和補體成分C9基因的iRNA例如雙鏈核糖核酸(dsRNA)組合物,以及使用此類iRNA例如dsRNA組合物來抑制CFB、C9、和/或C3的表達並且治療患有補體成分相關性疾病例如陣發性睡眠性血紅蛋白尿症和非典型溶血性尿毒症綜合徵的受試者的方法。