Abstract: This disclosure relates to the use of anti-A? antibody or antigen-binding fragment thereof to reduce brain amyloid plaques, or minimizes the occurrence of microhemorrhage during chronic dosing of an anti-A? antibody or antigen-binding fragment thereof. For example, the disclosure relates to the method of reducing brain amyloid plaques, comprising administering to a subject an anti-A? antibody or antigen-binding fragment thereof that binds to the same epitope as BIIB037 antibody, wherein the administration can reduce amyloid plaques in brain without affecting vascular amyloid, and wherein BIIB037 antibody binds to an epitope comprising amino acids 3-6 of A?.