4 days ago
Contraceptive pill for men that doesn't alter hormones is safe to take, study suggests
Oral female contraceptive tablets have been available for 60 years but there has never been an authorised male version.
Female tablets work by altering hormone levels to reduce the risk of conception but this approach has proven difficult in men because of severe side effects such as infertility and mood swings. These side effects are common in female versions.
YourChoice Therapeutics has developed the first non-hormonal contraceptive for men which works by blocking the production of a protein, which is needed to produce sperm, and not meddling with hormones.
The drug stops production of retinoic acid receptor alpha (RAR-alpha) in the body and this prevents it binding to vitamin A compounds and subsequently prevents sperm production.
Animal studies showed this mechanism to be 99pc effective and also found that sperm levels returned to normal after the medication was stopped, showing the contraceptive to be temporary and reversible.
Human trials began in 2023 when 16 healthy men who had already had a vasectomy were recruited to test the safety of the drug in people.
Data, published this week, show it to be safe and well-tolerated with no clinically relevant side effects in a significant step forward for the prospects of the drug, known as YCT-529.
The trial of 16 British men gave participants either the tablet or a placebo and conducted analysis on the participants to measure their blood, urine, mood and overall health.
Four different dosages were tested and all were found to be well-tolerated. The highest dose was the same as what was shown to be effective as a contraceptive in animal trials.
There was no reduction in testosterone levels, sex drive or any other hormonal imbalance, the scientists found.
'The positive results from this first clinical trial laid the groundwork for a second trial, where men receive YCT-529 for 28 days and 90 days, to study safety and changes in sperm parameters,' the study authors write in their peer-reviewed study in the journal Communications Medicine.
