The invention provides monoclonal antibody 6B8 and related antibodies. The 6B8 antibody binds to an epitope within residues 3-12 of IAPP. The antibodies of the invention are useful, for example, for treating disorders associated with IAPP accumulation, particularly accumulation of IAPP deposits. Such disorders include type 2 diabetes, metabolic syndrome, impaired insulin tolerance, impaired glucose tolerance, insulinomas, and related conditions.