Structural Basis for Activity and Specificity of an Anticoagulant Anti-FXIa Monoclonal Antibody and a Reversal Agent (Structure)

Inhibition of coagulation factor XI (FXI) may prevent thrombosis with less bleeding. DEF is a human monoclonal antibody that blocks the active form of FXI (FXIa). Ely et al. describe a structure that explains the anticoagulant function and specificity of DEF for FXIa and identifies an antidote for FXIa inhibitors.