A research study which received massive media coverage this week was the discover of a male contraceptive pill. If this can be successfully translated to humans the impact on society would be incredibly significant. This is why the study received a lot of press.
So what exactly was the experiment? How did they show this works? The scientists used their pharmacology knowledge to develop a drug which targets the production of sperm, which was then tested in mice.
Currently there are no drugs available as a male contraceptive, however, there are a few drugs in clinical trials which alter the amount of testosterone in the body (see NHS website). These drugs are accompanied with some worrying side effects due to the multi functional actions of testosterone in the male body. One of the biggest hurdles so far is a contraceptive pill which retains sexual desire, any hormonal drugs seem to suppress this. However, the drug reported in this study does not primarily target hormones and could therefore be advantageous.
The target of the drug in this study is the bromo- domain-containing protein (BRDT) – a protein expressed in sperms which is essential for spermatogenesis. A small molecule called JC2 has been developed, which inhibits the activity of BRDT. The drug JC2 was injected daily into male mice for a period of 3-6 weeks then the mice were allowed to mate with female mice.
The following findings in JC2 treated mice were observed:
- Sperm count was reduced by approximately 28%
- A significant reduction in the size of the testis
- Sperm mobility was reduced by approximately 4.5 fold
- The effect was reversible – stopping treatment allowed the mice to breed again
The next step is to try compounds with a higher affinity for BRDT and to study the long term effects of blocking BRDT. The successful translation of the drug from mice to humans is encouraging as BRDT is highly conserved between the two species.
The introduction of a male contraceptive pill will be interesting to follow. A few female comments suggest they wouldn’t trust their partner to be responsible and remember to take the pill. But isn’t it time we gave men the choice?