'Game-changer' male contraceptive drug shows promise, study suggests

Researchers say an on-demand male birth control pill is possible after a contraceptive drug that quickly and temporarily reduces fertility showed promise in mice.

The study’s co-senior authors Dr Jochen Buck and Dr Lonny Levin, who are professors of pharmacology at Weill Cornell Medicine, say the discovery could be a “game-changer” for contraception.

The findings show that mice given the drug inactivate an enzyme that produced sperm so it could not propel themselves forward.

Scientists say that this suggests the inhibitors (sAC) can reduce the movement of the mouse and human sperm, which is a key function.

The authors performed a series of experiments and found that while male mouse mating behaviour was normal, fertility was eliminated in the hours after the drug was given.

The contraceptive effectiveness was found to be at 100% in the first two hours and 91% in the first three hours, before returning to normal levels in 24 hours.

There were no found negative health impacts found when the drugs were continuously used for six weeks.

Although the scientists administered these drugs via injection in most experiments, they found that mouse sperm motility was also reduced by similar levels when taken orally.

Dr Melanie Balbach, a postdoctoral associate, explained that since sAC inhibitors wear off within hours, and men would take it only when, and as often, as needed, they could allow men to make day-to-day decisions about their fertility.

Further studies are needed, but if the drug development and clinical trials are successful, Dr Levin hopes to walk into a pharmacy one day and hear a man request “the male pill”. The findings are published in Nature Communications.

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