Revolutionizing Male Contraception: Baylor Researchers Discover Novel, Non-Hormonal Method to Inhibit Sperm Formation

The world population has been rapidly increasing, with projections suggesting that there will be 9 billion people in the world by 2037. This trend highlights the urgent need to address family planning, as advances in contraception have been limited in recent decades. Men still do not have an oral contraceptive option, which is a significant barrier to responsible family planning.

A team of researchers from Baylor College of Medicine, along with several collaborating institutions, have demonstrated a novel non-hormonal, sperm-specific method for male reversible contraception in animal models. The details of their study were published in the journal Science.

The researchers focused on identifying a small molecule that inhibits a protein called serine/threonine kinase 33 (STK33), which is essential for fertility in men and mice. Previous research has shown that STK33 is necessary for the formation of functional sperm. In mice, deleting the Stk33 gene results in sterility due to the production of abnormal sperm with poor motility. Men with mutations in the STK33 gene also experience infertility from similar sperm defects.

STK33 is considered a viable target for male contraception with minimal safety concerns. The researchers discovered specific inhibitors of STK33 and developed a compound called CDD-2807, which proved to be effective in reducing sperm motility and number, as well as fertility in mice. Importantly, the contraceptive effect of CDD-2807 was reversible, with mice regaining fertility after discontinuing treatment.

The researchers also presented the first crystal structure of STK33, which allowed them to design and optimize the compound for improved drug-like properties. Moving forward, the team plans to evaluate the effectiveness of this STK