Monoclonal antibody-based therapy.

Monoclonal antibodies have been developed for cancer therapy because they specifically target tumor-related antigens. The current design of antibodies and delivery strategies seeks to overcome the obstacles encountered in delivering antibodies to their targets. Protein engineering techniques to humanize murine antibodies diminishes the immune response, which develops against murine monoclonal antibodies, allowing for multiple doses. Antibodies linked to vasoactive substances or conjugated to liposomes increase antibody and drug localization to tumors. Altering the sizes of antibodies and the methods by which they are conjugated to radioactive isotopes have delineated methods to increase efficacy and decrease toxicity. Tumor growth factors increasingly are being targeted by antibody-based therapeutics. To enhance immune activation of cytotoxic effector cells, bispecific antibodies and antibodies linked to superantigens are being examined. Prodrugs are being converted to their active compounds at the tumor site by antibodies conjugated to enzymes. Finally, intrabodies which can bind to intracellular proteins and are important for the malignant phenotype of the cell, are being developed.