Controversial resveratrol triggers new headlines--this time for Alzheimer's

Georgetown's Dr. R. Scott Turner

Seven years ago GlaxoSmithKline ($GSK) paid $720 million to gain control of Sirtris, a Cambridge, MA-based biotech that had made headlines with its boasts about the beneficial nature of resveratrol, an ingredient in red wine which researchers had flagged as an antiaging remedy in animal studies. Sirtris, though, went on to dump a lead program two years later and then quietly sank out of sight after GSK later dismantled the unit and absorbed the R&D work as some investigators wrangled over whether those animal studies could ever be reproduced with similar results.

Resveratrol, though, remains a fascinating experimental therapy for many researchers.

Dr. R. Scott Turner, director of the Memory Disorders Program at Georgetown University Medical Center, recruited 119 Alzheimer's patients and tested a therapeutic grade formulation of resveratrol, looking at two suspected biomarkers for the disease, the soluble proteins amyloid beta 42 and Abeta 40.

Over the years, investigators have noted that levels of Abeta 40 drop in Alzheimer's patients while Abeta 42 remains stable, which might open a window into disease progression. Testing resveratrol in the patients, though, Abeta 40 levels remained level among the group getting purified resveratrol, while the control group registered telltale declines as their dementia worsened.

As is often the case with resveratrol, the idea of a fix like this instantly sparked headlines around the world, usually without the background history. But the news about the small study didn't mention if the therapy had any beneficial impact on patients' cognition or ability to complete routine daily functions--both core to determining efficacy.

"A decrease in Abeta40 is seen as dementia worsens and Alzheimer's disease progresses; still, we can't conclude from this study that the effects of resveratrol treatment are beneficial," Turner explains. "It does appear that resveratrol was able to penetrate the blood brain barrier, which is an important observation. Resveratrol was measured in both blood and cerebrospinal fluid."

In addition, he added, brain volume decreased in the resveratrol group, which could indicate a reduction in inflammation.

Turner got federal funds for the study and says there's good reason to push for a pivotal Phase III with more patients. This is, he adds, the longest and biggest study for resveratrol yet complete. But with industry evidently sidelined for now, the future of resveratrol remains uncertain at best.

- here's the release