C5 and paroxysmal nocturnal hemoglobinuria: Danicopan is a Factor D inhibitor studied as an add-on therapy to a C5 inhibitor (eculizumab or ravulizumab) in patients with PNH who have clinically evident extravascular hemolysis (Danicopan as Add-on Therapy to a C5 Inhibitor in Paroxysmal Nocturnal Hemoglobinuria (PNH) Participants Who Have Clinically Evident Extravascular Hemolysis; ClinicalTrials.gov.