New publication details journey of the molecule behind male birth control pill

MINNEAPOLIS, MN (1/12/26) — 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,” said Dr. Nadja Mannowetz, co-founder and chief scientific officer of YourChoice Therapeutics. “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.”

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.

About YCT-529

YCT-529 is a first-in-class new chemical entity, a retinoic acid receptor-alpha (RAR-α) inhibitor that is designed to prevent production of sperm cells in the testes as well as their release. YourChoice Therapeutics, a clinical stage biopharmaceutical company based in San Francisco, CA, is currently assessing the safety and efficacy of YCT-529 in a phase 2a clinical trial in New Zealand. YourChoice Therapeutics developed YCT-529 in collaboration with Dr. Gunda Georg, a globally recognized medicinal chemist and awardee of one of the largest NIH-funded Contraceptive Centers. The Male Contraceptive Initiative (MCI) has been committed to funding the early research and YCT-529’s phase one clinical trial in men. Established in 2018, the company received a $15M Series A investment in 2022. For more information, visit www.yourchoicetx.com and follow the company on LinkedIn.

About the University of Minnesota College of Pharmacy

Founded in 1892, the University of Minnesota College of Pharmacy is the only pharmacy school in Minnesota, with campuses in the Twin Cities and in Duluth. In 2022, the University’s medical laboratory science and occupational therapy programs were integrated into the college. The medical laboratory science program is the only accredited four-year baccalaureate degree program in a public institution in the State of Minnesota, with students on the Twin Cities campus. The occupational therapy program is the only public doctoral-level program in Minnesota and one of the oldest OT programs in the United States, with campuses in the Twin Cities and Rochester. Collectively, these programs advance the college’s mission to advance health through innovative research, evidence-based education, transformative practice initiatives, and community engagement. Learn more at pharmacy.umn.edu.