Reversible non-hormonal male contraceptive that targets the STK33 protein
Official title: Reversible male contraception by inhibition of serine/threonine kinase 33
Funded at Baylor College of Medicine · NIH-11321660 · Data updated 2026-11-12
Developing a non-hormonal medicine that temporarily blocks a sperm-related protein (STK33) to provide reversible contraception for adult men.
Quick facts
| Grant type | R01 grant |
|---|---|
| Study type | NIH-funded research |
| Funding institution | Baylor College of Medicine NIH-funded |
| Lab location | 1 site (Houston, United States) |
| Project start | August 1, 2024 |
| Project end | April 30, 2029 |
| Funding year | 2026 |
| Award (this year) | $631,413 |
| NIH project number | 5R01HD115711-03 |
| Project ID | NIH-11321660 on NIH RePORTER |
Who could benefit from this research
✓Could help
Adult men (21+) who want reversible contraception and would consider enrolling in future clinical trials are the most likely candidates.
✕Less likely to help
Women, minors, people seeking permanent sterilization, and men with infertility unrelated to STK33 are unlikely to benefit from this research in the near term.
What this research studies
Researchers are creating and testing drug candidates that selectively block the STK33 enzyme, which is enriched in the testes and needed for normal sperm shape and movement. They used DNA-encoded chemistry to screen billions of compounds and are optimizing molecules for potency, metabolic stability, and to remain outside the brain (peripherally restricted). Findings from mice lacking STK33 and a human family with an STK33 mutation that causes infertility guide the work, but the current work is preclinical lab and animal testing rather than treatments available to patients. If the best molecules are found, they would move into safety studies and future clinical trials in men.
Why it matters
Potential benefit: Could provide the first reversible, non-hormonal male contraceptive option that avoids altering systemic hormones.
How similar studies have gone: Genetic studies in mice and a human family show that loss of STK33 causes male infertility, but using drugs to reversibly block STK33 in humans is a novel and unproven approach.
Where this research is happening
-
Baylor College of Medicine
Houston, United States Active
Researchers
- Principal investigator: Matzuk, Martin M. — Baylor College of Medicine
- Study coordinator: Matzuk, Martin M.
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About this research
- This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
- Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
- For full project details, budget, and progress reports, visit the official NIH RePORTER page.