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Rita Rubin, USA Today, August 9, 2004
You can rub Rogaine into your scalp to try to regain the hairline
of your youth. You can inject Botox into your forehead to smooth
time’s inroads, at least temporarily. And, some scientists
predict, you’ll eventually be able to pop a pill to freshen
up the inside of your head as well.
Thanks to recent strides in understanding how the brain works,
it’s only a matter of time before medications specifically
designed to improve mental ability hit the market.
“The hallmark of these drugs is they don’t create
more memory,” says John Tallman, CEO of Helicon Therapeutics
of Farmingdale, N.Y., which plans to begin testing its most promising
brain drug in humans later this year. “What these drugs
really do is enhance the conversion process of short-term to long-term
memories.”
Besides Helicon (for the mountain in Greek mythology where Apollo
played with the Muses), companies with such evocative names as
Sention (apparently a play on sentient, which means conscious
or aware) and Memory Pharmaceuticals are focusing on medications
to treat patients whose brains are impaired by disease or injury.
But the real market for such drugs might be healthy people who
would simply like to be a little quicker on the uptake.
Building brains?
Americans already spend $1 billion a year on dietary supplements
claiming to boost brainpower, even though there’s little
evidence that they work, notes an article in the May issue of
Nature Reviews Neuroscience. From vitamin B12 to ginkgo biloba
to “BrainQUICKEN” capsules — “used by
top students at every Ivy League institution,” according
to the product’s Web site — health-food stores and
the Internet are rife with products promising to enhance memory
and learning.
Once the Food and Drug Administration allows a drug on the market
to treat, say, Alzheimer’s disease, doctors could prescribe
it “off-label” for any purpose they like, including
sharpening healthy minds dulled by age or fatigue. And Internet
shoppers would have their pick of Web sites selling the drugs
without even requiring a prescription.
To an extent, it’s already happening. Though it’s
not clear how widespread the practice is, high school and college
students who don’t have attention deficit-hyperactivity
disorder are taking Ritalin to help cram for exams. Scientists
have been known to pop Provigil, approved only to treat narcolepsy,
to increase alertness before speaking at professional meetings.
“People are already using a wide range of medical drugs
to improve their own performance,” says Sention CEO Randall
Carpenter, citing Viagra’s popularity with men who don’t
have erectile dysfunction as one example. “It’s almost
impossible to stop people if they want to do that.”
‘Normal’ cognitive decline
On its Web site, Memory Pharmaceuticals of Montvale, N.J., acknowledges
that the potential market for its compounds, one of which is being
tested in humans, might extend far beyond patients with Alzheimer’s
and other memory-robbing ailments. Though 37 million people worldwide
have Alzheimer’s disease, the company says, more than 180
million — or half of all people over 65 — are experiencing
“age-associated cognitive decline.”
“This decline is not clearly linked to a definable disease
condition and may be a ‘normal’ part of the process,”
the company says on its Web site.
How healthy?
Still, there’s no guarantee drugs that work in people impaired
by disease would also benefit healthy people who would simply
like to recall names more quickly.
For example, first-generation Alzheimer’s drugs Cognex
and Arricept block the breakdown of acetylcholine, one type of
neurotransmitter, a substance that enables nerve cells to communicate
with each other. Alzheimer’s patients’ have a shortage
of acetylcholine, but people with normal brains do not, so it’s
not clear what effect the drugs would have on them, says Steven
Rose, a director of the Brain and Behavioural Research Group at
the Open University in England.
Duke University researchers have found that the nicotine patch,
approved only to help smokers break the habit, boosts brain function
in people with mild to moderate Alzheimer’s disease and
adults with ADHD and schizophrenia. But earlier tests in healthy
volunteers found only a modest effect, says Edward Levin, a professor
in Duke’s psychiatry and behavioral science department.
The nicotine patch points out another obstacle toward developing
“smart drugs” for normal brains. “It has to
be as safe as water,” Carpenter says. “That’s
a very daunting task that few people want to try to accomplish.”
Perhaps somewhat surprisingly, Stanford University researchers
found that nicotine gum as well as Aricept, used to treat patients
with mild to moderate Alzheimer’s, did improve healthy,
middle-aged pilots’ performance in flight simulators. However,
Aricept also can cause side effects that would be pretty undesirable
in a pilot, such as dizziness, fainting and vomiting, says pharmacologist
Martin Mumenthaler, who led the study.
“The issue is: How do you specifically alter such a complex
organ as the brain without affecting anything else?” asks
biologist Robert Gerlai, a memory researcher at the University
of Hawaii. “The brain doesn’t just work on learning
and memory. It has all kinds of other functions.”
In addition, Gerlai and others in the field point out, there
is the potential risk that memory-enhancing drugs would work too
well, preventing users’ brains from distinguishing between
important and trivial information.
Some scientists say Helicon’s leading drug, aimed at activating
a protein involved in the formation of long-term memories, might
interfere with short-term memory, Tallman acknowledges.
Animal “memory models are pretty good, but it’s hard
to really get a total read on human memory without doing human
trials,” he says. Although Helicon has not yet begun testing
its drug in people, Tallman says he suspects that any adverse
effects on memory would be transient.
A mental ’jump-start’
Phase I trials, designed to assess the safety of experimental
drugs, are conducted in healthy volunteers. So besides monitoring
the volunteers for side effects, Sention, of Providence, R.I.,
and Memory Pharmaceuticals are administering tests to assess their
drugs’ effects on learning and memory.
Mark Bear, a Massachusetts Institute of Technology neuroscientist
and Sention co-founder, emphasizes that the Phase I studies were
too small to yield robust data about the drugs’ effectiveness.
Still, he says, “I would be willing to say that the results
were very encouraging.”
Though it would be unethical for Bear, 46, to test his company’s
drugs on himself, he does occasionally partake of a medication
that might be the first safe and effective smart drug on the market.
Modafinil, sold
as Provigil, was approved in 1999 for the treatment of daytime
sleepiness in narcolepsy patients. It’s not cheap. Web sites
sell 30 100-milligram tablets for around $200.
In a small study of healthy men published last year, Barbara
Sahakian of the University of Cambridge found that modafinil safely
improved performance on tests of memory and attention.
Sahakian says she and her collaborators limited their study to
men to eliminate the potentially confounding effect of women’s
menstrual cycles. But, she says, there’s no reason to think
that modafinil wouldn’t work the same in women.
“It’s probably the first smart drug that I’ve
seen,” says Sahakian, one of the co-authors of the “Nature
Reviews” article on cognitive enhancers.
Bear says he takes modafinil “to jump-start myself across
time zones,” not to enhance his mental performance.
He first asked his doctor for a prescription before traveling
to a scientific meeting in India. “I had to arrive and give
a seminar in the same day. I said to my doctor, ‘Look, I’m
going halfway around the world. I simply would not be able to
function’ “ without the drug.
Though Bear took modafinil to keep from nodding off in the middle
of his presentation, he acknowledges that “anything that
increases alertness will increase cognition.”
And anyone who has downed a double espresso — or two or
three — while studying for an exam or writing a report would
probably drink to that.
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