DS-1, A MODIFIED QUILLAJA SAPONIN, ENHANCES OCULAR AND NASAL ABSORPTION OF INSULIN

The purpose of this study was to test DS-1, a modified Quillaja saponi n, for its efficacy as an absorption enhancer. Anesthetized rats recei ving eyedrops or nosedrops formulated with regular pork insulin in sal ine showed no hypoglycemic response, indicating no systemic absorption of insulin. However, rats receiving eyedrops or nosedrops formulated with insulin plus 0.025-0.10% DS-1 showed rapid absorption of insulin and a concomitant decrease in serum D-glucose levels. No response was observed following sublingual or buccal delivery of insulin. In conclu sion, the modified saponin DS-1 was efficacious at enhancing nasal or ocular insulin delivery at extremely low concentrations. The mechanism of DS-1 action is not yet known.