Methods of using factor B inhibitors

A method of treating paroxysmal nocturnal hemoglobinuria (PNH) in a subject in need thereof, the method comprising orally administering to the subject 4-((2S,4S)-(4-ethoxy-1-((5-methoxy-7-methyl-1H-indol-4-yl)methyl)piperidin-2-yl))benzoic acid or a pharmaceutically acceptable salt thereof, at a dose of about 200 mg twice daily (b.i.d.), to thereby treat the subject, wherein the dose refers to an amount of anhydrous free base of 4-((2S,4S)-(4-ethoxy-1-((5-methoxy-7-methyl-1H-indol-4-yl)methyl)piperidin-2-yl))benzoic acid.