An experimental new drug that briefly blocks the male sperm is being hailed as a “game changer” in the search for an elusive birth control pill for men.
The drug was tested in pre-clinical trials in mice and showed 100 per cent effectiveness in preventing pregnancy, according to a peer-reviewed study published in Nature Communications on Tuesday.
Researchers at Cornell University injected the non-hormonal drug in male mice and among the 52 pairings that they tested, not a single female mouse got pregnant.
The drug works almost like an off-on switch as the sperm movement is blocked for up to 2.5 hours by using an inhibitor to target soluble adenylyl cyclase (sAC), which is essential for sperm motility and maturation. Motility then appeared to be restored the next day.
“So the idea is they take that pill about 30 minutes before they want to have intercourse and then their fertility is protected and then about 24 to 48 hours, their fertility comes back,” Dr. Melanie Balbach, a reproduction biologist at Weill Cornell Medicine and co-author of the study, told Global News.
It is an “on-demand” approach for male contraception that is not based on hormones and is “very different” than hormonal birth control pills for women, said Balbach.
Women on birth control pills typically have to follow a regular multi-week regimen to prevent ovulation.
In the case of this drug being designed by Balbach and her colleagues, “it really hopefully can be taken as often as the men want to have intercourse,” she said.
After mice, the drug is now being tested in rabbits that are “more similar to humans,” said Balbach.
However, it might take two to three years before they can start clinical trials and see if the drug is safe and effective for humans, she said.
“We hope in about six to eight years, if everything goes well, it will come to (the) market.”
So far, the main methods of contraception for men are condoms and vasectomy, but a number of drugs are being developed.
Women have several ways to control pregnancy such as pills, sponges, gels, IUDs, vaginal rings and diaphragms.
University of Ottawa professor Christabelle Sethna, an expert on the history of the birth control pill for women in Canada, said it’s “wonderful” to have more options “because women have been shouldering the burden of contraception for decades.”
She cautioned having a male birth control pill might mean condom use would drop, which is a concern for preventing sexually transmitted diseases (STDs) in the case of multiple partners.
If the drug does eventually make its way into the market after showing safety and efficacy, uptake will also be a challenge that will require social and cultural change, Sethna added.
“I think the marketing companies have a number of targets to hit if they want men to take up this pill,” she said.