20 August 2012
ByAppeared in BioNews 669
Scientists may now be one step closer to producing the first non-hormonal, male contraceptive pill after a successful animal study.
'Our findings demonstrate that, when given to rodents, this compound produces a rapid and reversible decrease in sperm count and mobility with profound effects on fertility', said Dr James Bradner, senior author of the study at the Dana-Farber Cancer Institute in Boston, USA.
The researchers showed that JQ1 works by inhibiting BRDT, a protein critical to fertility that instructs germ cells to grow into sperm cells. The result is a decrease in the number and quality of sperm, without any affect to the hormonal system and libido.
'There is no effect on the mouse's mojo. The animals exhibit the normal sexual behaviours and frequency of copulation', said Dr Bradner.
The study also showed that when the drug treatment was discontinued, sperm production and fertility was restored to normal levels.
'To date, most of the trials have attempted to stop sperm production by manipulating the male hormone testosterone through the use of injections or implants', explained Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield.
However, hormone treatments can have serious side effects. 'Non-hormonal targets are urgently needed', said Dr Bradner.
Professor William Bremner, of the University of Washington in Seattle and who was not involved in the study, told ABC News that since the development of condoms centuries ago, there has not been a new reversible contraceptive for men.
Though the drug offers promising evidence for the development of an oral pill for human contraception, Dr Bradner and colleagues are aware of the challenges in developing a new product for human use.
Professor Robert McLachlan, Director of Clinical Research at Prince Henry's Institute of Medical Research in Melbourne, Australia said further studies in animals would need to be performed before it could be trialled in men.
Talking to ABC News, he said: 'The development of a potential contraceptive is a very long and arduous process leading up to the first human studies. It will be fascinating to see how the drug evolves, but we know that such pipelines may require 15 years of evaluation and there are many potential pitfalls along the journey'.