So the company enhanced it to make it more bioavailable. They recently announced unpublished results of their early human trials of that drug, SRT-501 that they say demonstrated safety, as well as hinted at efficacy. "We reached statistical significance," Westphal says, adding that they plan to publish the data, along with early results from additional trials, in scientific journals. They published their preclinical trial results in the journal Nature.
They found that, "You could treat diabetes in the three key models–these are animal models of diabetes where it's very predictive when you see effects [such as] lowering blood sugar and improving insulin sensitivity–that you will see similar effects in human patients," he says.
And as they reported in Nature, they've now discovered other molecules that, in animal tests are a thousand times more potent. "We showed that you could develop molecules that had the same activity, but at 1000th the dose," says Westphal. "So these are the kind of things that you could imagine taking one small pill once a day. "
While longevity researchers have come to view aging itself as a host of diseases of failing metabolism, Westphal explains that they're focusing on one disease of aging–diabetes, because the FDA doesn't classify aging itself as a disease.
"Sirtris is focused on developing drugs that would be approved by the Food and Drug Administration, we're very focused initially on developing drugs to treat diabetes," he says. But since these genes have also been shown to stop other diseases of aging, like cancer and Alzheimer's, he adds that the company is well aware of the possibilities.
"What's particularly exciting is, when you target the genes that control the aging process, you seem to be able to treat all diseases of aging in a new and safe way. Diseases of aging include diabetes, Alzheimer's, cancer, inflammation. So, if we're right, this is actually potentially of profound importance for a number of the major killers of Western society," says Westphal.
The company also has some competition. Elixir Pharmaceuticals, also based in Cambridge, is targeting the sirtuins and other genes for treating obesity and diabetes. And it may well turn out that existing drugs that already have the FDA seal of approval will turn out to extend lifespan.
This research was published in Nature, Nov. 29, 2007 and funded by Sirtis Pharmaceuticals.