British men have become the first in the world to test a new hormone-free contraceptive pill that experts hope will make pregnancy prevention a ‘shared responsibility’.
A group of 16 volunteers at a clinic in Nottingham are involved in the trial of the drug, called YCT-529, to see if it can stop the formation of sperm.
The pill works by shutting off a protein called retinoic acid receptor alpha (RAR-alpha) in the body, preventing it from binding to a form of vitamin A.
And this, scientists hope, should stop sperm forming in the testes – and be easily reversible if men decide they are ready to have children.
A group of 16 volunteers at a clinic in Nottingham are involved in the trial of the drug, called YCT-529, to see if it can stop the formation of sperm
While the trial is taking place in the UK, the drug itself has been developed over the last 20 years by Professor Gunda Georg, from the University of Minnesota.
She said: ‘The last innovation in contraception was the birth control pill for women, and that’s more than 60 years ago.
‘The world is ready for a male contraceptive agent and delivering one that’s hormone-free is simply the right thing to do given what we know about the side effects women have endured for decades from the pill.
‘We consciously chose to inhibit the vitamin A signaling pathway in the testis because nearly 100 years of research has validated this pathway and shows that infertility can be reversed easily.’
Studies have shown that the drug was 99 per cent effective in preventing mouse pregnancies and decreased monkey sperm counts after two weeks.
It was found to be safe and fully reversible once the treatment had ended.
Surveys suggest that around a third of sexually active men in Britain could consider taking a male version of the pill. Currently their options are limited to withdrawal, condoms or a vasectomy.
Other male contraceptive pills being trialled use hormonal agents to suppress testosterone to prevent sperm production.
However, testosterone does not stop sperm production completely and it has also been linked to serious side effects such as increased risk of cardiovascular disease as well as weight gain, acne and mood changes.
The phase one trial is being carried out by YourChoice Therapeutics, a biopharmaceutical company which was founded with the goal of developing non-hormonal contraceptive products for men.
Researchers are exploring a male contraceptive pill, which could be taken 30 minutes before sex. An example of how one might work
Akash Bakshi, co-founder and CEO, said: ‘Contraceptives work only if they’re used.
‘YCT-529 blocks a protein – not hormones – to prevent sperm production. We believe this will be more attractive to men, most of whom view pregnancy prevention as a shared responsibility even despite today’s limited contraceptive options, which are permanent or only moderately effective.
‘The dearth of options reinforces the centuries-old view that pregnancy prevention is ‘a woman’s responsibility’. It’s not, and we’re committed to advancing the first hormone-free birth control pill for men that’s effective, convenient, and temporary.’
The Male Contraceptive Initiative, which has invested in the new pill, supports efforts to develop new birth control methods.
Executive director Heather Vahdat said: ‘The first human study for a hormone-free male birth control pill is a long-awaited milestone and a landmark achievement in the quest for reproductive autonomy.
‘While significant work lies ahead, we believe YCT-529’s first human study is a significant step toward a future where both men and women have the power to decide and control contraceptive use, pregnancy, and childbearing, a kind of health equity we believe is long overdue.’
The trial is also being funded, in part, by the National Institutes of Health, the US medical research agency.
