New publication describes the chemical journey of non-hormonal male birth control pill

A newly published manuscript authored by Dr. Gunda Georg, YourChoice Therapeutics and Columbia University Medical Center describes the chemical journey of YCT-529, a non-hormonal male birth control pill, and the promising molecular science behind it. The Journal of Medicinal Chemistry plans to feature the paper as a supplementary cover. Researchers are currently studying YCT-529 in a phase 2a human study. 

"We are pleased to share the drug discovery study of YCT-529 with the scientific community of the Journal of Medicinal Chemistry, exemplifying academic drug discovery and a successful public-private partnership," said Georg, Regents Professor in the University of Minnesota College of Pharmacy's medicinal chemistry department and director of the Institute for Therapeutics Discovery and Development (ITDD). 

The manuscript describes the validity of aromatic linker substitution, a chemical design process that identifies compounds capable of inhibiting retinoic acid receptor alpha (RAR-alpha)- a critical protein in sperm cell production. This strategy led to the discovery of YCT-529. The publication also includes efficacy and safety data from rat studies that demonstrate the in vivo potency of YCT-529. These studies demonstrate that YCT-529 effectively and reversibly suppressed sperm counts, which pregnancy outcomes validate. These results supplement previously published mouse and non-human primate data. 

We have conducted several studies with four different animal species, and all have shown safety and efficacy. This adds confidence that YCT-529's contraceptive effect is durable, reversible and not species-specific, which is significant because it adds rigor to a drug candidate that men will use long-term."

Dr. Nadja Mannowetz, co-founder and chief scientific officer of YourChoice Therapeutics

With nearly half of all pregnancies in the U.S. unintended, demand is growing for new male contraceptive options and data shows that men and women are open to using them. As a first-of-its-kind, hormone-free male oral contraceptive, YCT-529 has been shown to prevent sperm production by blocking access to a vitamin A metabolite in the testes in various non-clinical models. This mechanism of action has been established for nearly 100 years and supported by decades of published studies. In July 2025, Communications Medicine published YCT-529's first-in-human study results showing the candidate was well tolerated by male volunteers. In March 2025, it published the candidate's successful preclinical study, which showed that YCT-529 performed as effectively or better than the female birth control pill.