Cold water on female Viagra?
By Marie McCullough
Inquirer Staff Writer
A new study has found that the quality of women's lives in the bedroom
has nothing to do with the amount of testosterone in their blood.
This might seem to be bad news for the score of drug companies
developing testosterone products in hopes of tapping the estimated $1
billion market for a female counterpart to Viagra.
"Our study is going to frustrate a lot of doctors," said lead author
Susan Davis, an endocrinologist at Monash Medical School in Australia.
Treating female sexual complaints "is not just about giving
testosterone. It's far, far more complicated."
But the researchers who conducted the study are not counting
testosterone out. While levels in the blood may not be meaningful,
levels in the brain, bone and fat - where the hormone cannot be measured
- may affect the female libido.
"Our results," they concluded, "are not in conflict with testosterone
being used... to treat hypoactive sexual desire disorder" - the new term
for women affected by low libido.
The results do not support testosterone being used, either, Davis said
from Victoria, Australia.
The study, in today's Journal of the American Medical Association, is
sure to fuel controversy on the safety and science behind female
testosterone supplements - before a single one is approved.
In December, advisers to the Food and Drug Administration unanimously
voted that Procter & Gamble had not proved the safety of its
experimental testosterone patch, Intrinsa. A majority also judged
Intrinsa's effectiveness to be unproven in studies, since a placebo also
perked up menopausal women's sex lives.
Procter & Gamble is still seeking to market the patch in this country,
Europe and Canada, company officials said yesterday.
As for the Australian findings, P&G physician Kathryn Wekselman said
hormone levels did not always correlate with symptoms.
"If you look at estrogen levels, you cannot predict which menopausal
women will have hot flashes," she said. "So if that [disconnect] was the
same with testosterone, it would not be unprecedented."
Unpredictable results
But while estrogen clearly works for hot flashes, testosterone is
unpredictable for women with lagging libidos. In Intrinsa studies in
postmenopausal women, patch users had on average one more "satisfying
sexual" episode per month, over six months than women on a placebo; in a
second study, the patch made even less difference.
Still, doctors have for decades prescribed testosterone creams and pills
to improve female sex drive, particularly after a hysterectomy. The FDA
permits such "off-label" treatment.
The Australian study involved 1,021 women aged 18 to 75 who completed a
questionnaire on sexual well-being developed by Procter & Gamble.
(Although P&G did not fund the study, Davis has worked on the Intrinsa
research.)
The researchers measured their blood levels of testosterone as well as
DHEA sulphate, a hormone produced by the adrenal glands that is
converted to estrogen and testosterone.
A different approach?
While the testosterone level was irrelevant to the women's reported
arousal, desire, orgasm and self-image, low levels of DHEA sulphate did
correlate with sexual problems in women under 45 and, to a lesser
degree, in women over 45.
Still, researchers could not say DHEA therapy is a good idea, anymore
than they could say testosterone therapy is a bad idea.
New York City psychiatrist Lenore Tiefer, a critic of the push for
testosterone treatment, found that conclusion illogical.
"The one thing that does emerge is that DHEA may be useful," Tiefer
said. "But DHEA is an over-the-counter dietary supplement, so there's no
money in it."
Tiefer speculated that since testosterone was relatively difficult and
expensive to measure in the blood, drug companies may welcome the new
evidence that measuring it is pointless.
"The companies are going to spin this to say, 'Now we have proof that
you don't need to measure testosterone,' " Tiefer said. "The companies
want women to go directly from having subjective [sexual] distress to
getting the product - no diagnosis, no workup
