Male Birth Control Pill May Inactivate Sperm for a Day

A new drug can­di­date can ren­der male mice ster­ile with­in an hour and dis­ap­pear with­in a day, an exper­i­men­tal study showed Tues­day. This indi­cates the poten­tial for future “on-demand” male contraceptives.

The drug, which has not yet been test­ed in humans and is years away from being com­mer­cial­ly avail­able, joins a grow­ing list of male con­tra­cep­tives in development.

But now men have only two options: con­doms and pipe cuts.

Pre­vi­ous drugs have strug­gled, part­ly because side effects are thought to be a much high­er hur­dle for men (because there is no risk of preg­nan­cy) and part­ly because the phar­ma­ceu­ti­cal indus­try isn’t interested. .

“For women, the bur­den of con­tra­cep­tion is now all on us,” Melanie Bar­bach, a phar­ma­col­o­gy researcher at Weill Cor­nell School of Med­i­cine, told AFP.

“We want new options,” added Bal­bach, lead author of the study pub­lished in Nature Communications.

The researchers focused on an enzyme called sol­u­ble adenyl cyclase, which acts as an ‘on-switch’ for sperm, said study co-author Jochen Buck, also of the Weill Cor­nell School of Medicine.

When this enzyme is switched off, the sperm can no longer move.

In sev­er­al dif­fer­ent tests, the researchers found that com­pounds that inhib­it­ed this enzyme immo­bi­lized mouse sperm in 30 min­utes to an hour.

The com­pound showed 100% anti-preg­nan­cy effi­ca­cy in the first 2 hours, drop­ping to 91% in 3 hours.

After 24 hours, the mice’s sperm were mov­ing nor­mal­ly again.

Buck said researchers hope to devel­op a sin­gle, hor­mone-free pill that takes effect with­in an hour and lasts for six to 12 hours.

This is in stark con­trast to oth­er options in devel­op­ment, such as hor­mone gels cur­rent­ly being test­ed in humans, which take weeks or months to work and stop working.

No side effects were observed in mice. Pre­vi­ous stud­ies have sug­gest­ed that infer­tile men who per­ma­nent­ly turn off the sol­u­ble adenyl cyclase enzyme have a high­er rate of kid­ney stones.

Accord­ing to Dr. Buck, this is because the enzyme is always switched off, which is not the case for men tak­ing on-demand pills.

The researchers hope to have the first human tri­als with­in three years, but Bach said the final prod­uct could take eight years.

Susan Walk­er, a con­tra­cep­tive expert at Anglia Ruskin Uni­ver­si­ty in the UK who was not involved in the study, said that, like many oth­er ini­tia­tives that have failed, whether the pill will be com­mer­cial­ized is “a lit­tle questionable.

But the “sig­nif­i­cant advan­tage” of being almost imme­di­ate, she said, offers “the pos­si­bil­i­ty of watch­ing your sex­u­al part­ner take the pill.”

Accord­ing to founder Steve Kretschmer, con­sul­tan­cy Desire Line is work­ing to pre­dict the pen­e­tra­tion rate of var­i­ous male contraceptives.

“Ini­tial esti­mates sug­gest that con­sump­tion of the fast-act­ing, one-to-two-day, on-demand pill in the Unit­ed States could be three times high­er than Via­gra when it was first launched,” he told AFP.