Patent ID: 7959919

Claim:
A method of inhibiting factor B-dependent complement activation in blood of a subject in need thereof, comprising administering to blood of the subject a therapeutically effective amount of an anti-factor B monoclonal antibody or antigen-binding fragment thereof effective to inhibit complement activation, the anti-factor B monoclonal antibody or antigen-binding fragment thereof in an in vitro assay having a greater effectiveness at preventing factor B binding to properdin-bound C3b than preventing factor B binding to free C3b; preventing the formation of Bb; reducing C3a, C5a, and C5b-9 generation; reducing C3 conversion into C3a and C3b; reducing C5 conversion into C5a and C5b; reducing the activation of neutrophils, monocytes and platelets; and inactivating cells bearing C3a and C5a receptors, wherein administration of the therapeutically effective amount of the monoclonal antibody or antigen-binding fragment thereof does not decrease factor B levels in the blood.