Resveratol, naturally found in red wine, stimulates a gene known as SIRT1, which has been linked with extended lifespans in rodents. The new study is the first time similar effects have been replicated in humans.
Sirtris' proprietary formulation of the drug significantly reduced blood sugar in 67 diabetic patients as compared with a placebo group. The results are an important milestone in bringing resveratrol-related drugs to market.
The study, however, ran just 28 days and had conservative goals: to measure whether a resveratol formulation called SRT501, which is five times easier for the body to use than naturally occurring resveratol, was safe and had some activity in humans. Getting the drug through the regulatory process will take until at least 2012, the company said.
Patients in the trial were given 2,500 or 5,000 milligrams of the drug in liquid form. The unusually high doses were necessary because resveratrol is not a very potent molecule. That's why the company is also working with other molecules -- potential drugs -- that are unrelated to resveratrol but also stimulate the SIRT1 gene. Some of the molecules could be up to 1,000 times more potent than resveratrol, he added.
Still, SRT501 was effective enough that Sirtris is continuing to push the drug through clinical trials. They have started a Phase IIa study combining SRT501 with the most common diabetic drug, metformin. The IIa trial should be done by the second half of 2008.