Researchers
in the United States are working on new types of male contraceptives, even
though the American pharmaceutical industry has not shown much interest
and the public believes women are more likely to use birth-control products
than men.
While contraceptive
choices for women expand in the United States -- including a birth-control
patch now before the Food and Drug Administration for approval, and more
intrauterine devices -- contraceptive options for men have remained a choice
between vasectomy and condoms.
"It's true that
people (in the United States) do not see the male population to be very
willing to endorse contraception of the couple," Dr. Regine Sitruk-Ware,
executive director of contraceptive development at Center for Biomedical
Research at the Population Council in New York, told United
Press International.
Despite this
hurdle, U.S. researchers press on.
The Population
Council has developed a product called MENT, a progestin implant, like
the female IUD Norplant, which is placed in the upper arm. The idea is
to manipulate sperm production without threatening male genital function,
Sitruk-Ware explained. MENT is about to undergo the final phase of drug
testing required by the FDA.
CONRAD, a research
company based in Arlington, Va., also is testing various forms of male
contraception using the approach of sperm suppression. One possibility
is a male birth-control pill containing progestin to lower sperm production
and a testosterone derivative to allow men to
have enough testosterone
to maintain normal penile functioning and libido.
Preliminary
studies on this type of pill are underway in Seattle and Los Angeles, CONRAD
director Henry Gabelnick told UPI, to determine appropriate dosages.
But as with
women who take oral contraceptives, Gabelnick said there is concern whether
a male pill is viable since people are prone to forget to take a daily
drug. Implants that deliver hormones, he said, may be a better alternative
for men because the devices only need to be replaced every four to six
months.
One scientist
working on male contraception from a different angle is Lonny Levin, an
associate professor of pharmacology at Weill Cornell Medical School in
New York. His research has not yet extended beyond the laboratory, but
what Levin hopes could be a "potential target for a male
contraceptive" is a molecule
called soluble adenylyl cyclase or sAC.
Without the
sAC molecule, sperm cells are unable to undergo the biochemical changes,
which usually occur as they travel through the female reproductive tract,
necessary to fertilize an egg.
Instead of suppressing
sperm, Levin said disabling the capabilities of sAC could help reduce the
risk of pregnancy. It is too soon to say, he added, whether this could
be a drug taken before sexual intercourse or be developed into some other
medication or device.
Not only is
male contraception absent from the U.S. public radar, it also does not
appear to be generating a great deal of interest from U.S. pharmaceutical
companies. However, Europe has its eye on some American products.
U.S. pharmaceutical
companies lack interest, Sitruk-Ware explained, because "it's not as big
a market as female contraception. The woman is more motivated because if
it fails, she pays the price, but the male does not have the motivation."
European countries
traditionally have been more receptive to putting innovative contraceptives
and reproductive health care products on the market and American researchers
hope U.S. pharmaceutical companies will follow suit.
Sitruk-Ware said Berlin-based
Schering A.G., which manufactures the new intrauterine device Mirena and
has an office in Monteville, N.J., is interested in MENT.
It is possible,
she said, whether it is Population Council's product or someone else's,
that a male contraceptive could reach the U.S. market by 2006 or 2007.
Schering also
is interested in work done by CONRAD, and Levin said while he has not had
any interest from U.S. pharmaceutical companies, he also has heard from
a German company.
Schering spokeswoman
Jane Kramer told UPI Schering was researching male contraception currently
"not being considered for the United States," but did not elaborate further.
A lack of interest
in a male contraceptive in the United States -- compared to the controversy
surrounding female reproductive health care -- also may explain why researchers
say they have not encountered opposition from pro-life, religious or conservative
groups. They also have not faced many problems on Capitol Hill.
"The definition
of blockbuster drug keeps on creeping up," Gabelnick said, adding right
now male contraceptives do not look like they are going to be the next
Viagra, the widely prescribed drug for male erectile dysfunction.
Levin said despite
what pharmaceutical companies believe, there is a market for male contraceptives.
"It would be
a boon, I would think, that would make life so much simpler for the male
portion of the population," Levin said. "I can't imagine that it wouldn't
be well-received, a male contraceptive, especially one that's easy to take."
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Copyright 2001 by United
Press International.
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