Scientists have recently discovered a method to prevent sperm motility. This opens up potential opportunities for the development of male contraceptive pills.
Tests on mice have shown that this drug causes sperm to become immobilized for at least a few hours — long enough to prevent them from reaching the egg. More experiments are planned, moving towards trials on rabbits.
The drug currently being tested will inhibit or block sAC. (Illustration: newscientist.com).
According to BBC (UK), unlike contraceptive pills for women, the male contraceptive does not involve any hormones. Scientists say this is one of the advantages of the method they are exploring, as it will not eliminate testosterone and will not cause side effects associated with male hormone deficiency.
Instead, they are targeting a cell signaling protein called Soluble adenylyl cyclase (sAC). The drug being tested will inhibit or block sAC, which is essential for sperm motility.
In preliminary research on mice, funded by the US National Institutes of Health and published in the journal Nature Communications, a single dose of the drug named TDI-11861 immobilized sperm before, during, and after mating. The effect lasted for about 3 hours, and the drug ceased to have an effect after 24 hours.
One of the researchers involved in the study, Dr. Melanie Balbach from Weill Cornell Medicine in New York, stated that TDI-11861 has the potential to be an easy-to-use contraceptive method. If TDI-11861 proves effective in humans, men could make daily decisions about their fertility. However, experts warn that this drug will not protect against sexually transmitted diseases, and condoms would still be necessary for that.
Professor Allan Pacey at the University of Sheffield (UK) noted: “There is a strong demand for an effective oral contraceptive for men, and although various methods have been tested over the years, none have been brought to market. The method described here, which involves removing an enzyme that is crucial for sperm movement, is a truly novel idea. The fact that it might work and can be quickly reversed is quite intriguing. If the mouse trials can be translated into clinical trials in humans with a similar level of effectiveness, this could be the male contraceptive we have been searching for.”
Meanwhile, other researchers are exploring another approach to prevent sperm motility by blocking a type of protein on the surface of sperm.
