Male contraception: update on the three tracks that will be presented at a congress

A gel to apply on the shoulder

This is the most advanced line of research, even if the studies are still far from making it possible to envisage rapid commercialization. This is a gel to apply every day on his shoulder. It contains both a female hormone, called progestogen, to block the formation of spermatozoa, and testosterone, in order to compensate for the effects of the first on libido or hairiness. Why go through the skin and not orally, like the female pills? This is because testosterone is better assimilated through this channel. Absorbed in a pill, its effects disappear even before the end of the day. Via a gel, they persist longer.

The trials, mainly carried out in the United States, are currently in phase 2, the most advanced for ongoing work on a male contraceptive. Carried out with approximately 200 couples, they should give a first idea of ​​the effectiveness of this method, whose safety and reversibility are already sufficiently proven.

According to endocrinologist Régine Sitruk-Ware, who is taking part in these trials and also organizing the Paris symposium, the initial results are good enough to speed up progress. “This product seems very effective and very well accepted”, she told AFP. The researchers are already going to ask the American health authorities to authorize the next phase, which will make it possible to really ensure the effectiveness of the product by testing it on a much larger number of people. However, we are still a long way from being put on the market. “In principle, you could say five years from now but that’s the optimistic view, there are always unforeseen hurdles to overcome during development.“, warns Ms. Sitruk-Ware.

Pills still under study

Because of the difficulties in assimilating testosterone orally, a male pill is difficult to conceive. But researchers continue to follow this path and have obtained encouraging first results on humans in recent years. To achieve this, it was necessary to give up a concept: one which, like the gel described above, consists of combining two hormones, a progestogen associated with testosterone. Instead, researchers work from a single hormone. This has the two desired effects at the same time: progestogen, by limiting the production of spermatozoa, and androgen, by replacing the role of testosterone. We know, in fact, two synthetic hormones that can play this dual role. Research is therefore underway on pills made from each of them.

In recent years, this research has passed a first stage, which guarantees that these pills are well tolerated, therefore without serious and systematic side effects. We also know that they do not seem to have an irreversible effect on fertility. It now remains to assess whether they are sufficiently effective. “Unfortunately, due to the Covid, the tests and the results take a long time”explained to AFP the researcher Stephanie Page, who is working on one of these pills.

A gel that blocks sperm

This is an even less advanced track than the two previous ones, but for which the first human trials should begin at the end of the year to first ensure that it is well tolerated without marked side effects. The principle is to inject a gel which blocks the sperm during ejaculation, without preventing it. The promoters of this method, developed by the American startup Contraline, promise years of tranquility after the injection.

This operation is similar to a vasectomy even if, unlike this one, the designers ensure that the effect of the gel is systematically reversible. The idea is also not new. A similar concept, says Risug, has been studied for several years in India. The researchers had reported positive results in 2019, but have since given no news.