New diabetes drug passes early tests.

The drug exenatide stabilizes and can reduce blood sugar in diabetes patients for whom standard medications don't work well, two studies show.

In one trial, Ralph DeFronzo of the University of Texas Health Science Center at San Antonio and his colleagues gave injections twice daily to 336 people with type 2, or adult-onset, diabetes. Some received exenatide; others got a placebo. In the other study, John Buse of the University of North Carolina School of Medicine at Chapel Hill and his team randomly assigned 377 diabetes patients to receive exenatide or a placebo. The volunteers were already taking diabetes medication: metformin (Glucophage) in the first trial and a sulfonylurea drug in the second.

After 30 weeks, patients in either trial who were getting exenatide had kept their blood sugar in check significantly better than did those receiving the placebo. Roughly two-fifths of the patients getting exenatide saw their blood sugar decrease, nearly always without inducing the shakiness, weakness, and other symptoms that result when blood sugar drops too low--a condition called hypoglycemia.

The results were presented earlier this month at the 64th Scientific Sessions of the American Diabetes Association in Orlando, Fla.

Exenatide is a synthetic form ofexendin4, a compound found in the venomous saliva of the Gila monster (SN." 8/16/03, p. 104). Exendin-4 is similar to glucagonlike peptide-1 (GLP1), a compound made in people by cells that line the intestines. Once released into the blood, GLP1 switches on insulin-making beta cells in the pancreas. However, GLP1 is so short-lived that it's unsuitable as a drug. Exendin-4 and exenatide remain active in the body longer.--N.S