The contraceptive options available for men are limited to condoms and vasectomies, with no hormone-based male birth control pills available in the market. The birth control pill, as well as other methods of birth control, are plentiful for women, but men remain without sufficient male contraceptive options. The University of Minnesota, together with Columbia University and Your Choice Therapeutics, developed YCT-529 as a hormone-free male contraceptive pill as a potential solution. Testing of this medication to stop sperm production recently started because it demonstrated promise as a clinical treatment.
The scientific research aimed its efforts at blocking a particular biological mechanism that controls sperm development. The research team discovered that active vitamin A metabolite all-trans-retinoic acid (ATRA) maintains vital significance for male germ cell development. When bound to retinoic acid receptors (RARs), ATRA carries out its function in spermatogenesis processes. Studies included the RARα receptor because its blocking in mice leads to male sterility together with no detectable health complications.
YCT-529 is designed as a specific inhibitor for RARα. The drug underwent laboratory testing in mice and non-human primates to evaluate its ability to stop sperm production. A series of mating trials and tests helped the researchers determine how effective YCT-529 was in preventing pregnancy and its potential for fertility restoration following drug removal.
The laboratory tests performed on animals proved successful. The administration of YCT-529 at 10 mg/kg/day for mice throughout four weeks produced a 99% effectiveness rate to block conception. Spermatogenesis suffered disruption because of the provided treatment, causing temporary infertility to develop in treated mice. Markedly, fertility was completely restored within six weeks after stopping the drug.
Researchers conducted YCT-529 drug tests using non-human primate subjects. Sperm production was inhibited when patients received YCT-529 orally, yet they didn’t show any detectable unwanted effects. The drug treatment ceased, and the primate subjects regained normal sperm count levels during a 10-to-15-week period. Studies have proven that YCT-529 inhibits sperm production in both mice models and non-human primates, and this reversible action makes the compound suitable for human use.
Scientific progress in male contraception reaches a major advancement with the development of YCT-529. The hormone-free pill functions by binding to the RARα receptor that directly controls sperm development. Promising research outcomes in animal studies demonstrate that YCT-529 holds potential as an acceptable contraceptive option for future male contraception. Research testing in non-human primates demonstrated promising results that strengthen the viability of administering YCT-529 to humans for medical trials. The development of YCT-529 represents a promising option in contraceptive research because it may contribute to solving worldwide concerns about unintended pregnancies.
References: Mannowetz N, Chung SS, Maitra S, et al. Targeting the retinoid signaling pathway with YCT-529 for effective and reversible oral contraception in mice and primates. Commun Med. 2025;5:68. doi:10.1038/s43856-025-00752-7
