Studies on mice have shown that the substance is as much as 99 percent. effective. Human clinical trials are scheduled for later this year.
An American research team working on an oral contraceptive for men saw initial success. YCT529 was 99% effective, said AFP, University of Minnesota graduate Abdullah Al Noman. There were no side effects in the studies. The results mark an important step towards fairer responsibility for contraception, the team said.
“Many studies have shown that men are interested in sharing the responsibility for contraception with their partners,” said Noman. So far, only condoms or vasectomy have been available for men.
No hormones
The contraceptive pill for women is based on hormones that affect the menstrual cycle and, to some extent, the psyche. In addition, taking it can lead to serious side effects such as thrombosis. Earlier attempts to create a male counterpart have relied on the male sex hormone testosterone. However, side effects such as weight gain, depression and elevated cholesterol have also appeared, which in turn increases the risk of heart disease.
On the other hand, YCT529 attaches to a protein called the retinoic acid alpha receptor, which plays an important role in sperm production. In the body, vitamin A is converted into other molecules, including retinoic acid, which is important for cell growth, sperm formation, and embryonic development. Retinoic acid needs to interact with RAR-alpha in order to do its job. The laboratory experiments now presented have shown that mice in which RAR-alpha is blocked are not fertile.
Long test phase
The test mice were orally administered the YCT529 substance for four weeks. Male mouse sperm counts dropped drastically during this time, and fertilization was prevented by 99 percent, according to the research team. The mice were fertile again four to six weeks after the drug was discontinued.
Professor Gunda Georg, who led the study with Noman, was optimistic about approving the market over the next five years. “There is no guarantee it will work,” said Georg, “but I would be really surprised if we didn’t see the effectiveness in humans.” Human clinical trials are slated to start in the third or fourth quarter of this year.
(APA / Evdin)