Danicopan

Danicopan binds reversibly to complement factor D (FD) and acts as a selective inhibitor of FD function. By inhibiting FD, danicopan selectively blocks the activation of complement alternative pathway (AP), leading to prevention of the production of multiple effectors, that include C3 fragments, after AP activation. The 2 other complement pathways (classical and lectin) remain active. Danicopan’s inhibitory effect on AP activation inhibits the deposition of C3 fragments on PNH red blood cells; such deposition is a key cause of the EVH which can become clinically significant in a small subset of patients with PNH on a C5 inhibitor. Maintenance of C5 inhibition controls the lifethreatening pathophysiological consequences of terminal complement activation underlying PNH.