[A trial with immunotherapy of ovarian cancer by idiotype vaccination. Activation of the idiotype network in patients with advanced ovarian cancers by treatment with monoclonal antibody OC125].

Up to date, the positive effect of immunotherapy, using tumour-associated antigens or tumour cells of ovarian carcinomas, is still vague. Another and effective approach to overcome an experimentally induced tolerance, is the presentation of an definitive antigen in a different surrounding by the induction of the idiotypic network. Antibodies against a tumour-associated antigen are used to induce following antibodies, which are directed against the variable antigen-binding group, the so-called idiotype of the antibody-vaccine. Then, the induced antibodies carry a mirror image of the tumour-associated antigen and are therefore able to modulate the host's immune response against the tumour. For the induction of this system, we used the monoclonal antibody OC125 as a F(ab)2-fragment, which is directed against the tumour-associated antigen CA125 of epithelial ovarian carcinomas. 12 patients with advanced ovarian carcinomas received antibody fragments of the OC125 in the course of radioimmunodetections since 1985. Until April 1990 only these 5 patients, who developed the anti-idiotypic antibodies after the vaccination, are still alive. Our first results with the induction of the idiotypic network system for patients with advanced ovarian carcinomas indicate, that in spite of the same surgical and chemotherapeutical treatment, patients show a delayed clinical course after the induction of the idiotypic system. The transfer of the definitive tumour-associated antigen in an idiotypic antigen, seems to modulate the immunoresponse of the patients and in this way also the clinical course of a malignancy.(ABSTRACT TRUNCATED AT 250 WORDS)