Male contraceptive gel enters major human testing phase

Male contraceptive gel enters major human testing phase
A new gel-based experimental male contraceptive is set to undergo a major trial involving more than 400 couples
A new gel-based experimental male contraceptive is set to undergo a major trial involving more than 400 couples
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A new gel-based experimental male contraceptive is set to undergo a major trial involving more than 400 couples
A new gel-based experimental male contraceptive is set to undergo a major trial involving more than 400 couples

A Phase 2 trial into the efficacy of a male contraceptive gel is about to get underway bringing modern medicine closer than it ever has before to finally developing a male birth control drug, decades after the female contraceptive pill hit the market.

Finding a simple male contraceptive compound that is safe, effective and reversible has been relatively elusive for scientists.Outside of condoms and vasectomies, birth control has remained well and truly in hands of women. A male contraceptive agent, some have argued, is simply a much more difficult pharmacological challenge: stopping the production of an egg or two a month seems to be much easier than limiting the efficacy of millions of constantly regenerating sperm.

However, several exciting innovations are rapidly being developed –from an injectable compound acing its early animal trials to a more traditional "pill" passing the first phase of human safety trials earlier this year. The most advanced male contraceptive prospect though is a novel gel, designed to be used once a day, and now moving into a serious phase 2b trial set to establish whether it actually stops unwanted pregnancies or not.

The gel is called NES/T and contains two hormonal compounds. The primary compound is called Nesterone, a progestin hormone formulated to lower sperm production by blocking testosterone production in the testes. The second compound is a concentration of testosterone designed to maintain blood levels of the hormone, important for general health and mood, but low enough to not kick-start sperm production.

Prior human trials into the gel, rubbed onto a man's arms and shoulders once a day, have found the contraceptive agent to be low in harmful side effects, and effective in reducing overall concentrations of sperm. This new trial is set to encompass over 400 couples worldwide and will follow use for well over a year to clearly find out if the gel actively prevents pregnancies.

The trial will run through several stages, first the men will use the gel daily for up to 16 weeks while being monitored for unexpected side effects. By that point tests should reveal whether sperm level shave declined to levels below recommended conception thresh-holds.

At this point the second phase is for the men to use the gel as their only form of birth control for 52 weeks. All men enrolled into the study must be part of a committed, monogamous couple, with both members signing onto the trial. After a year of using the gel as the only form of birth control, the men will discontinue the treatment and be observed for 24 weeks to examine any after effects and to make sure sperm levels return to normal.

"The success of a reversible contraceptive for men requires an approach that reduces the production of sperm without impacting a man's testosterone levels or ability to produce sperm at a later date," says Christina Wang, lead researcher and a study principal investigator. "The challenge is achieving the right combination of Nestorone and testosterone at the right time."

This is the first serious, real-world test into a male contraceptive for some time, and all members signing up for the trial must be aware and willing to enter into a pregnancy if the gel proves ineffective. The results from this trial won't be known until around 2022, and if positive, the treatment will move into an even larger, final phase 3 trial before it can ultimately reach the market.So all up, despite this being the most advanced male contraceptive currently in development, it still may be close to ten years before it reaches the general public – and that is if all goes to plan.

"Expanding male contraceptive options could help make family planning more of a shared responsibility between women and men,"says Regine Sitruk-Ware, co-director of the trial, explaining the urgent need to develop an effective male contraceptive treatment."Safe, effective, and reversible tools for men to control their own fertility gives new meaning and significance to the term 'family planning.' No matter the challenge, we must continue to innovate and develop new products to improve lives."

The trial is currently recruiting subjects in California, Kansas and Washington, before expanding to a number of other locations worldwide. Interested participants can look at the selection criteria here.

Source: UW Medicine

Hmmm, rubbing a gel all over your arms and shoulders every day seems tedious. No way to simplify that? Sure would be nice if it were a once a day pill instead.
Brian M
Even if it works it doesn't seem to be the most sensible solution since it requires the woman to be 100% reliant on her partner for protection and does nothing to protect if she falls off the monogamous bandwagon (more common than you think).
As an added level of protection - then yes useful or where the female contraceptive is not a viable alternative.
But 100% better than vasectomy, which in most cases is irreversible and can causes problems if the relationship breaks up and the man has a new partner wanting children (read cost to the health service).
Expanded Viewpoint
So what's the plan for a woman who gets pregnant? Using a birth control product of ANY kind tends to mean that a child is not welcome in the picture, right? Or is this just a paid for means to an end to prove the scientist's conception (no pun intended there!) of a male birth control system on a best/worst case scenario?? And what if the male develops some kind of physical abnormality or disease from this chemical "cocktail"? How will his partner be compensated for her loss? Messing around with Nature on that level is so fraught with dangers and uncertainties, it's best to not go down that path. This is why we have live animal testing, so human lives are not put at so much risk. Or am I missing something here?