US Patent 8435539 Delivery system for cytotoxic drugs by bispecific antibody pretargeting

The present invention relates to methods and compositions for pretargeting delivery of therapeutic agents. In preferred embodiments, the pretargeting method comprises: a) administering a bispecific antibody with a first binding site for a disease-associated antigen and a hapten on a targetable construct; b) administering a targetable construct comprising at least one therapeutic agent. In preferred embodiments, the bispecific antibody is made by the dock-and-lock (DNL) technique. In a more preferred embodiment, the targetable construct comprises one or more SN-38 moieties.