The present invention provides antibodies directed against C-terminal and central epitopes of Αβ that preferentially bind compact plaques relative to diffuse plaques. The invention also provides methods of treating patients to reduce or eliminate the presence of compact plaques of Αβ and associated symptoms. In one aspect, the present invention provides a method of treating a patient diagnosed with mid- or late-stage Alzheimers disease, comprising administering to the patient an effective regime of an antibody that binds to an epitope within residues 12-43 of Αβ and preferentially binds compact plaques relative to diffuse plaques. In some cases, the patient has been diagnosed with mid-stage Alzheimers disease. In some cases, the patient has been diagnosed with late-stage Alzheimers disease.
