Following recent trials for a hormone-based male contraceptive, another experimental new type of contraceptive, which blocks sperm flow with a gel, has been successful in monkey trials. Vasalgel creates a semi-permeable barrier which, once injected into the vas deferens, prevents sperm from crossing and causes them to be reabsorbed by the body.
The company behind the innovative creation says a two-year trial shows the gel works and is safe in primates. There will hopefully be enough evidence to begin tests in human males within a few years. If these are successful, regulatory approval will be requested to make the gel more extensively available.
This would be the first new type of male contraceptive to hit the market in many decades. At the moment, men have two main options of contraceptive; to wear a condom to catch the sperm, or have a sterilising operation (vasectomy) to cut or seal the two tubes that carry sperm to the penis from where they are made in the testicles.
Vasalgel has the same end effect as vasectomy, but researchers plan to make the reversal easier and with a higher success rate, should a man later decide he wants to have children. The plans will be that another injection should dissolve the semi-permeable gel barrier, making sperm fertile once again. This worked in early tests in rabbits, but the researchers have yet to prove the same in monkeys and humans.
The non-profit company researching Vasalgel, the Parsemus Foundation, has used grants and fundraising to get this far. Researcher, Professor Pacey commented: “I would imagine there is a worldwide market for a new male contraceptive, but trials in humans and more long-term safety data are required before we will know if it is a success.”