A team of scientists has made headlines after claiming that a male contraceptive compound being developed was 99% effective in animal tests.
The male contraceptive, which can be taken by mouth, targets a protein in the body called retinoic acid receptor alpha, or RAR-α, which plays a role in cell growth and sperm formation.
Researchers looked at this protein and designed chemical compounds that would effectively lock it into cells. They found that one compound in particular, called YCT529, was effective in doing this.
When given to male mice for four weeks, it reduced sperm count and was 99% effective in preventing pregnancy without any observable side effects, according to a press release from the American Chemical Society ( ACS). The mice were able to father babies again within four to six weeks after they stopped taking the chemical.
Their findings were presented at the ACS 2022 Spring Meeting held March 20-24.
According to Gunda Georg, head of the University of Minnesota’s department of medicinal chemistry, who was involved in the work, human clinical trials are expected to begin in the third or fourth quarter of this year.
The search for a male birth control pill has been going on for decades, but none have yet been made available. Currently, the two contraceptive methods available to men are condoms and vasectomy, the latter being a surgical procedure.
Several other methods are under study. One type of hormonal male birth control pill, 11-beta-methyl-19-nortestosterone dodecylcarbonate, works by reducing the levels of hormones needed to produce sperm.
A Phase I trial of the pill, conducted by researchers at the University of Washington School of Medicine and UCLA a few years ago, found that subjects receiving the pill experienced drops in levels of two hormones associated with sperm production with reported mild side effects including fatigue, acne and headaches, according to Clinical Trials Arena. The effects were reversible after discontinuation of treatment.
Another type of pill called DMA undecanoate, which also works by suppressing male hormones to decrease sperm production, is also being studied.
Hormonal pills are a popular birth control method for women, but they can cause side effects, including weight gain, headaches, breast pain, irregular periods, mood changes, and decreased desire sex, according to the American Academy of Family Physicians.
There are other potential methods for men that do not involve pills. ADAM is a method of birth control researched by the medical device company Contraline. It would work by injecting a gel into the vas deferens, a tube that carries semen to the penis in preparation for ejaculation.
The gel is designed to prevent sperm from passing through this tube. Eventually the gel liquefies and the barrier to sperm flow is removed.