According to researchers who have discovered a cell pathway, or switch, that prevents sperm from swimming, an on-demand, non-hormonal male contraceptive pill may actually be feasible.
Tests performed on mice indicate that it keeps sperm stunned for at least a few hours, which is long enough to prevent them from reaching the egg.
Prioritizing rabbits over humans, numerous additional tests are planned and required.
Users could take a pill an hour before sexual activity and watch the time to see when it wears off.
It does not use hormones, in contrast to the female contraceptive pill.
One benefit of the strategy under investigation, according to scientists, is that it won't suppress testosterone and result in any side effects associated with a deficiency in male hormones.
Instead, they are focusing on a cellular signaling protein known as soluble adenylyl cyclase, or sAC, as the "sperm-swim" switch. The experimental male contraceptive suppresses or blocks sAC.
A single dose of the medication, known as TDI-11861, rendered sperm immobile prior to, during, and following mating in a preliminary mouse study that was supported by the US National Institutes of Health and published in the journal Nature Communications.
For about three hours, the effect persisted. It seemed to have completely worn off after 24 hours.
It showed promise as a reversible, simple-to-use contraceptive, according to one of the scientists, Dr. Melanie Balbach from Weill Cornell Medicine in New York.
Men may only need to take it as often as necessary if it ultimately proves effective in humans. They were capable of making daily decisions regarding their fertility.
However, experts caution that it would not offer protection against sexually transmitted infections. That would require condoms.
There is an urgent need for an efficient, reversible oral contraceptive for men, according to Prof. Allan Pacey, professor of andrology at the University of Sheffield. Despite numerous approaches having been tested over the years, none have yet made it to the market.
"The method described here, which involves blocking a key enzyme in sperm that is essential for sperm movement, is a really original concept. It's actually pretty thrilling that it can act and can be reversed so quickly.
This may be the male contraceptive method we have been looking for if human trials can be conducted with the same level of success as those done on mice. ".
While this is going on, other researchers are examining a slightly different pathway to stop sperm swimming, which involves blocking a protein on the surface of sperm.
