Antigen-specific composition and in vivo methods for detecting and localizing an antigenic site and for radiotherapy

摘要

A composition comprises an antigen-specific antibody or antigen-binding fragment thereof labeled with Iodine-124 at a site other than, and which does not significantly interfere with, the antibody-antigen binding site. An in vivo method of radiotherapy directed to an antigenic site comprises administering to a subject in need of the therapy an amount of the antigen-specific composition described above effective to attain a reduction of the size of a tumor associated with the antigen. An in vivo method for detecting and localizing an antigenic site in a subject in need of such detection comprises administering to the subject an amount of the antigen-specific composition of the invention effective to localize the antigen-antibody binding site and scanning the subject's body with a positron-emitter detector to attain the localization of the site. An in situ method of radiotherapy directed to an antigenic site in a subject in need of such therapy comprises detecting and localizing the site by the in vivo method described above and thereafter in situ delivering a positron-emitting labeled antibody chelate capable of binding to either the I-124 labeled antibody or fragment thereof, or to the antigen at a site other than the antibody-antigen binding site.