The First Hormone-Free Male Birth Control Pill Advances in Clinical Trials
YCT-529 Could Revolutionize Contraception with a Safe, Effective, and Reversible Option for Men
For decades, contraception has largely been the responsibility of women. Now, researchers have made a significant step toward changing that dynamic with the development of YCT-529, a hormone-free male birth control pill that has shown promising results in preclinical and early human trials.
Developed by YourChoice Therapeutics in collaboration with the University of Minnesota and Columbia University, YCT-529 is the first orally administered male contraceptive that does not rely on hormones. Instead, it works by selectively inhibiting retinoic acid receptor-alpha (RAR-α), a protein necessary for sperm production.
This innovative approach sets it apart from previous male contraceptive efforts, which primarily focused on hormonal methods that interfere with testosterone.
Promising Research and Clinical Trials
The research on YCT-529, published in Communications Medicine, has demonstrated its high efficacy and safety in animal studies.
Tests on mice found that the drug effectively prevented pregnancy within four weeks by blocking a key protein (RAR-α) needed for sperm production. Importantly, once the drug was stopped, fertility returned to normal within six weeks.
In larger animals (non-human primates), YCT-529 also lowered sperm production within two weeks, and there were no noticeable side effects. When the drug was discontinued, sperm levels fully returned to normal within 10–15 weeks.
These findings suggest that YCT-529 could be a reliable, reversible birth control option for men without the risks associated with hormone-based methods.
YourChoice Therapeutics completed the phase 1 clinical trial in 2024, which assessed the safety and tolerability of YCT-529 in humans. The trial, conducted in partnership with Quotient Sciences in the UK, involved 16 male participants and confirmed that the drug was well-tolerated with no significant side effects.
Based on these results, researchers have now moved forward with further testing, including additional studies in mice and non-human primates, to refine dosage and evaluate long-term effects. The next step is a human clinical trial, which will involve a larger group of human participants to further assess the drug’s effectiveness and safety.
Why YCT-529 Matters
Traditional male birth control research has focused on hormonal methods, which suppress testosterone to reduce sperm production. However, hormonal approaches often cause side effects such as weight gain, acne, mood changes, and an increased risk of cardiovascular disease.
Additionally, testosterone suppression does not completely eliminate sperm production and can vary in effectiveness based on individual genetic factors. YCT-529 avoids these risks by targeting a non-hormonal pathway, making it a potentially safer and more appealing option for men.
The demand for male contraceptive options has grown in recent years. Surveys indicate that many men and women view contraception as a shared responsibility, yet male options remain severely limited.
With nearly half of pregnancies in the U.S. being unplanned, introducing a reliable and reversible male contraceptive could have a significant impact on reproductive health. Expanding male contraceptive options would also help alleviate the burden on women, who have traditionally faced the majority of contraceptive side effects and responsibilities.
What’s Next for Male Birth Control Pills?
As additional preclinical studies continue, researchers and investors are optimistic about YCT-529’s potential. If proven safe and effective in phase 2 clinical trials, this pill could provide men with a convenient, reversible birth control method for the first time.
Future trials will focus on long-term effects, user adherence, and overall satisfaction with the male birth control pill.
