Small excerpt.
"Population is growing at a rapid pace in many economically developing countries and there is a continuing need of an alternate method for regulation of fertility. We proposed several years back a birth control vaccine which induces the formation of antibodies against the human pregnancy hormone, the human chorionic gonadotropin (hCG). These inventions are described in patents issued in India, U.S.A. and several other countries. (Ref. EP 204566, JP 62286928, CA 1239346, U.S. Pat. No. 4,780,312, CN 8603854). We describe now another invention which generates antibody response of a long duration against hCG after a single or a limited number of injections.
Whereas the possibility of controlling fertility by raising antibodies against hCG is known from our previous studies and those of others, the vaccines utilized earlier were conjugates of two or more peptides such as the natural beta hCG peptide of 145 amino acids linked to tetanus toxoid or other carriers. In another modality, the beta hCG peptide was associated with alpha oLH and then linked to carriers (Talwar et al 1988; U.S. Pat. No. 4,780,312). These vaccines demand purification and preparation of the constituent proteins from natural sources.
The cost of some of these is at present very high which will be restrictive to their large scale use in family planning programs of economically developing countries. Moreover these vaccines demand three injections for primary immunization followed by a fourth as booster. A
major advantage of the present embodiment is the possibility of getting satisfactory and sustained antibody response with
one primary injection and at most one booster. Another interesting feature is the
low cost at which this vaccine can be prepared and made available for large scale use.
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