lampalizumab lampalizumab lampalizumab (inn) is an antigen-binding fragment of a humanized monoclonal antibody that binds to complement factor d; it was developed as a potential treatment of geographic atrophy (atrophy of the retinal cells, retinal pigment epithelium, and choriocapillaris) secondary to age-related macular degeneration. lampalizumabmonoclonal antibodytypefab fragmentsourcehumanized (from mouse)targetcfdclinical dataroutes ofadministrationintravitrealatc codenoneidentifierscas number1278466-20-8iuphar/bps8294chemspidernoneuniiuwu93y99r3keggd10440chemical and physical dataformulac2068h3214n546o676s13molar mass46958.39 g·mol−1 one of the two phase 3 clinical trials (spectri) was interrupted on september 8, 2017 due to failure to meet primary end point. the second phase 3 clinical trial (chroma) also failed to meet its primary end point. these two failures have called into question whether complement inhibition is a sound strategy for geographic atrophy.