The present invention is directed to an immunizing composition containing an antigenic product such as a multiple antigen peptide system (MAPS) or a filamentous bacteriophage displaying an AβPP epitope spanning the β-secretase cleavage site of AβPP and a method for inducing an immune response against the β-secretase cleavage site of AβPP using this immunizing composition. The present invention is also directed to antibodies against the β-secretase cleavage site of AβPP and their use in a method for inhibiting the formation of amyloid β.
