Male contraception

Sep 29 2007

For decades, pundits have predicted new contraceptives for men within the next 5 to 10 years.

Are we really getting any closer? Judging from work presented at the second "Future of Male Contraception" conference, the answer may finally be yes.

But will men actually use a new method if researchers make one? Elaine Lissner, director of the nonprofit Male Contraception Information Project, says demand is the least of the problems. "You'll never have all men interested, but attitudes have really changed-- studies consistenly show a majority of men would consider it. You have to remember, between condoms and vasectomy, men in the U.S. are already taking care of a third of contraception. Just imagine if they had another non-permanent option."

Kirsten Thompson, director of the International Male Contraception Coalition, concurs. "Some men are quite desperate for better control over their fertility. They're looking for something they can really count on."

Among the developments announced at the conference:

• Researchers from the University of Pittsburgh and BIOQUAL Inc. showed they could provide contraception in monkeys with no hormones and no shots needed. (Monkeys are used for studies because of their similarity to humans.) The monkeys had no moving sperm after they took a compound called CDB-4022, and their fertility bounced back completely by 16 weeks. The researchers hope this will be a new nonhormonal contraceptive that can be taken as a pill; in survey results presented at the conference by the International Male Contraception Coalition, 61% of men listed a nonhormonal drug as their first choice. Safety studies will be the next step.
• A testosterone-like pill ("selective androgen receptor modulator") already in human testing as an osteoporosis and muscle-wasting treatment may have a side benefit: it could work as a hormonal contraceptive that could be taken as a pill. Until now, most "male Pill" research has used a combination of shots, implants, or gels. The SARM's industry support (by GTx, Inc.) gives it a good chance at commercialization.
• Another androgen that can be taken orally, Dimethandrolone Undecanoate (DMAU), was effective at reducing sperm numbers in rabbits if taken at a low, but not high, dose. Rabbits regained their fertility when they stopped the drug.
• Makers of the Intra Vas Device are expected to announce effectiveness data showing "substantial equivalence to traditional vasectomy methods” in a study of 90 men. The Intra Vas Device blocks sperm in the vas deferens, the tube sperm swim through that is cut in vasectomy. The set of plugs can be removed if a man changes his mind, and animal studies have shown that fertility returns if it is removed after short-term use. The next step will be to find funding for long-term studies of effectiveness and fertility return.
• Developers of a home sperm test ("SpermCheck") reported excellent results in men. The test perfectly matched more expensive laboratory tests in detecting whether men's sperm count is above or below 200,000-300,000 per millileter, an extremely low number (normal counts are above 20 million per millileter). When this test hits the market, it will help men who are using "do-it-yourself" methods such as simple wet heat and suspensories. It will also allow men who get vasectomies to know when their sperm are cleared out, without going to the doctor. About 1 in 6 American couples uses vasectomy as a contraceptive method, with more than 500,000 men opting for the procedure each year.

Researchers from around the world are also announcing new targets for contraception, and incremental progress on hormonal approaches ("the male Pill"). Many other teams will present late-breaking news during the poster session, 7-9 pm the 27th.