Prime Highlights
- The non-hormonal male pill, YCT‑529, is safe and acceptable in early human trials.
- The one-time dose had no effect on mood, sexual desire, or hormones, with no effect of food on the drug’s absorption.
Key Fact
- The pill works by silencing a receptor essential to sperm development, without hormones.
- Effect on fertility in lab animal tests reversed within a few weeks, with 99% effectiveness preventing pregnancy.
Key Background
Male contraception for many years has been reliant on condoms or permanent vasectomy procedures. The world has long dreamed of a reversible, safe, and easy pill for male contraception. YCT‑529 is a milestone moment. As a non‑hormonal male contraceptive, it targets the retinoic acid receptor alpha (RAR‑α), which sperm production requires. By inhibiting this process, sperm production can be stopped without changing testosterone levels and libido and mood.
Preclinical tests on animals have also been record-breakers. In mice, the pill didn’t permit pregnancy 99% of the time after four weeks and fertility resumed after six weeks off the drug. The same happened in primates, with sperm count plummeting within two weeks and returning to normal within 10–15 weeks of treatment. Importantly, these were done without hormonal disruption or behavioral change, and YCT‑529 is a prime candidate for male fertility.
Recently finished Phase 1a trial evaluated the drug’s safety in 16 healthy vasectomized men between 32 and 59 years of age. Capsules were taken orally as a single dose of 10 to 180 mg. No unwanted side effects or change in the significant health parameters, including hormone levels, heart output, mood, or libido, were noted from any dosage. The trial also determined that food has no effect on the pill being absorbed—a consideration that will have to be kept in mind when the pill is used in the future in real-world situations.
With this promising test, YCT-529 advances to 28- and 90-day dosing studies to examine long-term safety and contraceptive effectiveness. If all goes well, this pill could revolutionize birth control for men by offering a hormone-free, reversible, and safe alternative to men and couples everywhere.
