The invention relates to agents and to pharmaceutical compositions for reducing the formation of amyloid and/or for promoting the disaggregation of an proteins. The compositions may also be used to detect amyloid.

An engineered phage-derived particle (PDP) for expressing a transgene in a target cell transduced with a bacteriophage, the PDP includes (i) less than about 500 bp of DNA from the bacteriophage genome, (ii) an ITR-flanked therapeutic gene up to 20 kb, (iii) an endosomal escape sequence, (iv) a nuclear localization sequence, and (v) a cell-specific targeting moiety. The PDP may escape lysosomal degradation, traffic across the nuclear envelope and expressed a therapeutic gene in a mammalian cell.