Studies of Midaglizole (DG-5128): A New Type of Oral Hypoglycemic Drug in Healthy Subjects

Abstract

Midaglizole (DG-5128), 2-[2-(4,5-dihydro-1H-imidazol-2- yl)-1-phenylethyl]pyridine dihydrochloride sesquihydrate, is a novel α2-adrenoceptor antagonist. Its effects on plasma glucose, immunoreactive insulin (IRI), and immunoreactive glucagon (IRG) in healthy male volunteers were investigated. Volunteers received single oral administrations of midaglizole (150–500 mg), multiple increasing oral administrations on 3 separate days (150–300 mg 3 times daily), or successive daily oral administration for 1 wk (200 mg 3 times daily). The hypoglycemic action of midaglizole was observed within 0.5–1.0 h after its administration and thereafter for 5 h. The maximum hypoglycemic effect was found 1.0–1.5 h after administration. Midaglizole decreased postprandial hyperglycemia ina dose-dependent manner. In the fasting state, midaglizole significantly increased IRI secretion and suppressed IRG secretion. Midaglizole inhibited epinephrine-induced platelet aggregation after successive administration for 1 wk (200 mg 3 times daily). The plasma half-life of midaglizole was only 3 h, and the drug was rapidly excreted into the urine and feces, with >80% in its unchanged form, within 24 h. Midaglizole did not affect the results of any clinical or laboratory tests performed. Our data indicate that midaglizole is a possible hypoglycemic agent. Further clinical investigations are required to confirm its effects on diabetes mellitus.