Antiaging drug trials

[Guest guest]

Hi All,

It would be nice to have effective antiaging drugs. It

may take decades to develop them.

The below appears to be an update.

News

Nature Medicine 11, 240 (2005)

Antiaging drug trials compel creative testing methods

Emma Marris

Figure legend:

Long wait: Proving that a medicine slows aging is a tough task for

aspiring biotech

companies.

-- J. Jun/Detroit Free Press

The day when doctors prescribe pills to combat aging may sound a

long way off. But

medical researchers are already starting to test such drugs in

clinical trials—and

encountering scientific and regulatory obstacles along the way.

Over the last few years, biologists have identified a slew of

compounds that prolong

the life of animal models such as yeast, worms and mice. On the basis

of these results,

they have formed a handful of companies around the world and are

embarking on clinical

trials in humans.

Showing that a drug prevents aging in people, however, is proving

almost impossible.

The obvious test is to give one group of people the drug, and another

a placebo, and wait

to see which lives longer. But this would take at least a decade, be

enormously expensive

and spell bankruptcy for a cash-strapped biotech firm. " No companies

have money to last

that long, " says Sinclair at Harvard Medical School, Boston,

whose studies on the

antiaging compound in red wine called resveratrol led him to start

Waltham,

Massachusetts-based firm Sirtris Pharmaceuticals.

One way that Sinclair and other researchers plan to get around

this problem is to show

that a new drug delays or halts diseases associated with aging,

without actually waiting

for individuals to grow old. They hope to gain regulatory approval

for slowing diabetes

or arthritis, for example, and then carry out further trials to

examine whether the drug

also prevents these diseases from developing in the first place.

This approach is being taken at Elixir Pharmaceuticals, a company

based in Cambridge,

Massachusetts, that is planning human trials of molecules associated

with aging in yeast

and the worm Caenorhabitis elegans. The company is attempting to get

drugs approved for

market by showing that they prevent type 2 diabetes, says Bard

Geesaman, Vice President of

Medical Development.

Neither the US Food and Drug Administration (FDA) nor its

equivalent, the European

Medicines Agency, has ever approved a medicine specifically to combat

aging. But if a

company can convincingly demonstrate that a drug prevents a specific

disease, officials say

that it should be approved for that particular use. " Much of

preventive medicine is, in a

sense, antiaging medicine, " says Orloff, an official in the

FDA's Center for Drug

Evaluation and Research.

But once such drugs hit the market, they raise the prospect that

some people will use

them as broad spectrum antiaging drugs even though their long-term

side effects are

unknown.

Indeed, some may already be swallowing prescription drugs, such as

cholesterol-lowering statins and anticonvulsants, which have been

shown to extend the life of animal models.

" In the absence of human studies, it would not be advisable to take

these medications to

delay aging, " says Kerry Kornfeld, who studies such therapies at

Washington University in

St. Louis, Missouri.

Those in the field believe it will be decades before a drug is

approved specifically

for combating aging. In order to do so, researchers will probably

need to find genes or

other biological molecules whose levels vary with a person's age and

show that the drug

stops this change. Until such trials are completed, it is

irresponsible to label a drug

'antiaging', says Leonard Hayflick who studies gerontology at the

University of California,

San Francisco.

Al Pater