Improved Immunogenic Formulations for Antigonadotropin Response
Effective control of fertility by immunization with beta-hCG has been demonstrated in non-human primates (Stevens, 1974;Hearn, 1976; Tandon et al., 1981, 1984) and rats (Hulme et al., 1980). A vaccine consisting of beta subunit of hCG conjugated with tetanus toxoid (TT) was proposed earlier (Talwar et al., 1974, 1976). This vaccine induced antibodies to both hCG and TT and thus provided additional immunoprophylactic benefit against tetanus. After initial animal experiments and toxicology studies, Phase I clinical trials were conducted with this vaccine in 63 women of reproductive age in six centres located in five countries. AntihCG antibodies were formed in 61 out of 63 recepients without any significant side effects and disturbances (Kumar et al., 1976, Hingorani and Kumar, 1979; Shahani et al., 1979, 1982;Nash et al., 1980). The response was reversible with a duration of 300 to 500 days in good responders. The main limitation of this vaccine was the variability of the antibody response from individual to individual and those with inadequate titres were not protected from pregnancy. This presentation will describe an improved formulation which can generate higher antibody titres in a larger percentage of the recepients.
KeywordsHuman Chorionic Gonadotropin Tetanus Toxoid Significant Side Effect Medroxyprogesterone Acetate High Antibody Titre
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