Fig. 1. Blockade of terminal complement activation by eculizumab. There are 3 known pathways for initial complement activation: classical, alternative, and lectin pathway. These 3 pathways converge at the point of C3 activation. The final pathway starts with the formation of C5 convertase. Eculizumab inhibits terminal complement activation by binding to C5 and preventing the formation of membrane attack complex. Reprinted from Brodsky. Blood reviews 2008;22:65–74, with permission from Elsevier.24).
