A group of researchers announced on Wednesday that they had developed an oral male contraceptive that is 99 per cent effective in mice and has no side effects, and that human trials could begin by the end of the year.
The findings will be presented at the American Chemical Society’s spring meeting, and they represent a significant step forward in men’s birth control options and responsibilities.
Md Abdullah Al Noman, a graduate student at the University of Minnesota who will present the work, says that researchers have been interested in a male equivalent since the female birth control pill was first approved in the 1960s.
In addition, Norman said, “Multiple studies showed that men are interested in sharing the responsibility of birth control with their partners,” but there have only been two effective options available up until now: condoms or vasectomies.
Moreover, vasectomy reversal surgery is costly and does not always work.
The female pill uses hormones to disrupt the menstrual cycle, and previous attempts to create a male equivalent focused on testosterone, the male sex hormone.
The problem with this approach was that it resulted in weight gain, depression, and higher levels of cholesterol called low-density lipoprotein, which increases the risk of heart disease.
The female pill has side effects as well, including the risk of blood clotting, but because women are more likely to become pregnant without contraception, the risk calculation is different.
Noman to develop Non Hormonal Contraceptive
Noman, who works in Professor Gunda Georg’s lab, focused on a protein called “retinoic acid receptor (RAR) alpha” to develop a non-hormonal contraceptive. Vitamin A is converted to various forms in the body, including retinoic acid, which is involved in cell growth, sperm formation, and embryo development.
To perform these functions, retinoic acid must interact with RAR-alpha, and lab experiments have shown mice without the gene that creates RAR-alpha are sterile.
Meanwhile, Noman and Georg developed a compound that inhibits RAR-action alphas as part of their research. With the help of a computer model, they found the best molecular structure.
“If we know what the keyhole looks like, then we can make a better key — that’s where the computational model comes in,” said Noman.
In order to minimise potential side effects, their chemical, known as YCT529, was designed to interact only with RAR-alpha and not with two other related receptors, RAR-beta and RAR-gamma.
YCT529, when given orally to male mice for four weeks, significantly reduced sperm counts and was 99 per cent effective in preventing pregnancy, with no side effects.
However, four to six weeks after stopping the drug, the mice were able to reproduce again.
The team is collaborating with a company called YourChoice Therapeutics to begin human trials by the third or fourth quarter of 2022, according to Georg, who received funding from the National Institutes of Health and the Male Contraceptive Initiative.
“I’m optimistic this will move forward quickly,” she said, predicting a five-year or less timeline to market.
In addition, she said, “There is no guarantee that it will work…but I would really be surprised if we didn’t see an effect in humans as well.”
A persistent question about future male contraceptive pills has been whether women will trust men to use them.
However, surveys have shown that most women have faith in their partners and that a significant number of men are willing to try the medication.
“Male contraceptives will add to the method mix, providing new options that allow men and women to contribute in whatever way they deem appropriate to contraceptive use,” says the Male Contraceptive Initiative, a non-profit that raises funds and advocates for male contraceptive use.