Injections trial breakthrough also highlights a lack of progress since the 1950s to develop a tablet as good as birth control available to women

Contraceptive jabs for men may work - but what about the male pill?

Gregory Pincus, the maverick scientist who co-invented the female contraceptive pill, first tried to come up with a male equivalent in the 1950s. Nearly six decades on we are still waiting.



Friday’s news that male contraceptive jabs are almost as effective as the female pill is remarkable as much for the lack of progress it highlights as for the impressive result the trial delivered.

There are genuine scientific reasons why creating a male pill is tricky. But today’s results, together with a separate advance earlier in the week , make it a good time to ask whether the main obstacles are technical or a lack of will to develop the drug.

A central scientific challenge in developing a male pill is achieving the right balance of hormones that provides reliable and reversible contraception without inducing unacceptable side-effects.

Getting this right is a tightrope walk and the research fell just on the wrong side of the line. The World Health Organisation decided to stop enrolling men on its trial earlier than planned after being alerted to side effects, including low mood, acne and higher than usual libido (today some coverage interpreted this as a bonus of the drugs, although there is no suggestion that this is how the men or their partners saw it).

Participant safety must always be the first consideration when running clinical trials. It is worth noting, though, that three-quarters of the 300 men who took part in the trial said they would continue to use this method if they had the choice – and the decision to halt the trial was not unanimous.

Richard Anderson, a professor of clinical reproductive science at the University of Edinburgh and a co-author, says: “It was a big disappointment when the trial was stopped, as the trial monitoring committee were happy with progress and safety, but another WHO committee made the decision.”

The scientists did not attempt to quantify whether the side-effects were comparable or worse to known side-effects of the female pill, but we know that these can also be substantial.

“There are many couples for whom the female pill is not an option,” says Sarah Jones, a reader in pharmacology at the University of Wolverhampton, who is working on an alternative form of male contraceptive.

“It has terrible side-effects as well for some women. It’s not much of a choice. I’m sure there are couples that would relish this [male contraceptives].”

A second challenge, for the male contraception, is that the hormones they normally rely on are quickly metabolised by the liver, meaning that it’s difficult to package the drugs in a pill form. Again, it is worth noting that most of men on the trial said they would be happy to go forward with the injection method.

Anderson and colleagues are due to start another trial using a similar hormone combination delivered through a gel that men could rub onto their chest each morning.

Male contraceptive jab almost as effective as female pill, trial shows Read more

There are also new findings suggesting that targeting the sperm directly – by using a fast-acting pill or a nasal spray that a man could take before sex, for example – rather than using hormones might work. Until now, this approach had eluded scientists, because sperm is so impenetrable – or, as Jones puts it, “you just can’t get into the little buggers”.

She published findings this month showing that designer compounds could be smuggled inside sperm cells and target proteins that are required for the sperm to swim, essentially stopping them in their tracks.

The progress convinces Anderson that a male contraceptive will be available eventually. “It’s just disappointing that it’s going so slowly,” he adds.

Focus groups run by Anderson and others convince him that there is a clear and immediate demand. “About 90% of women we saw at a family planning clinic said it was a good idea, to share the responsibility,” he says.

“They say: ‘I’ve done that [taken the pill] for 15 years and had a baby. Come on it’s someone else’s turn.’”

However, funding from pharma companies – essential to run the trials involving thousands of men that would be required to get a product licensed – is not forthcoming.

Herjan Coelingh Bennink, who until 2000 was global executive vice-president of the reproductive medicine programme at the Dutch pharmaceutical company, Organon, has offered an insider’s perspective on why this might be the case.

“At board level it was only middle-aged white males,” Bennink told Mosaic , an online science magazine produced by the Wellcome Trust, this year. “I tried to explain how important it could be, but they never got further than saying to each other, ‘Would you do it?’ ‘No, I wouldn’t do it’. It was not considered male behaviour to take responsibility for contraception.”

Anderson said that commercial factors may have also impacted the decision to shift away from developing a male pill. “I’m not convinced by that characterisation,” he says. “Though it probably does have a grain of truth,” he says.

Undoubtedly, there are still scientific hurdles to be overcome before we have a safe, reliable male contraceptive.

But science is not there to solve life’s simple problems. When someone at the European Space Agency said let’s chase down a comet 250m miles away and land a robotic probe on it, nobody said “That sounds easy – let’s do it”.

If we’re looking for reasons why we’re still so far from equality in who bears the burden of birth control, let’s not place lack of scientific ingenuity at the top of the list.

• This article was amended on 29 October 2016. Herjan Coelingh Bennink was global executive vice-president of the reproductive medicine programme at Organon, not Schering as a previous version said.