C5 and paroxysmal nocturnal hemoglobinuria: Over time, interest has arisen in developing additional C5 inhibitors with different modes of administration and therapeutics targeting other components of the complement cascade, especially broader C3 inhibition and proximal complement cascade factors, such as D and B. Eculizumab biosimilars have also emerged.90,91 Results from an ongoing phase 3 clinical trial have shown noninferiority of a novel subcutaneous (SC) formulation of ravulizumab compared with IV ravulizumab at day 71 in eculizumab-experienced patients with PNH.45 Current approved and future C5 treatments are listed in Table 2.