Intrauterine administration of peptide drugs for systemic effect

High molecular weight drugs in general, and peptides/proteins in particular, are usually delivered by parenteral routes because they are poorly absorbed or degraded in the gastrointestinal tract. Long-term, repeated injections are often required because of the drug's short half-life, and the chronic nature of many diseases. To optimize therapy, it is essential to search for a non-parenteral route of drug administration. We describe here the absorption and the systemic biological effect of model drugs, after instillation into the uterus of the rat. In addition, we describe here results of calcitonin and insulin absorption from controlled-release devices inserted in the rat uterus. The amount and duration of the hypoglycemic and the hypocalcemic effects induced by intrauterine delivery of insulin and calcitonin, respectively, were equivalent to those obtained after subcutaneous injections. The therapy of a number of clinically important diseases could benefit from this discovery.