A new type of male contraceptive is currently being tested in animals. It may prevent pregnancy and is completely reversible. The male contraceptive is a polymer gel trademarked under the name of Vasalgel. Parsemus Foundation in California is developing the gel.
Earlier in 2017, the gel was effective in preventing rhesus monkeys from pregnancy for up to two years. The gel is injected into the vas deferens of men and acts as a barrier to sperm. The vas deferens are small tubes that help transport sperm from the testes.
Science Alert reported that when faced with the sperm, the injected gel embeds itself into the gel or gets “reabsorbed by the body.” The Parsemus Foundation conducted trials on rabbits in 2016 and reported showing no sperm cells after the gel was used a year after the procedure. While there were “slight changes” to lining cells, there were not “serious and didn’t seem to be worsening with time.”
In the rhesus monkey trials, the adult male rhesus monkeys (16 total) were put in the same area as nine fertile female rhesus monkeys but did not produce offspring. Elaine Lissner, executive director of the Parsemus Foundation said that it “was important here was that this worked and was safe in animals similar to humans,” she said to CNN during last month’s trial on rhesus monkeys.
The gel, after being injected into the testes, remains as a “soft gel-like state,” allowing water-soluble molecules to pass but nothing larger. Vasalgel’s predecessor was a male contraceptive gel plug named reversible inhibition of sperm under guidance (RISUG). While it started in India a few years before Vasalgel, the RISUG is “struggling through human trials for want of volunteers. The Parsemus Foundation hopes to start testing with human volunteers in 2018.
Researchers at the Parsemus Foundation injected a solution of sodium bicarbonate that dissolved the gel, therefore allowing the animal to breed again. Donald Waller, Ph.D., lead author, and researcher said the results of the gel’s reversibility show that the gel can be removed allowing a “quick return of sperm flow. Waller said that “more flushing” may be needed to completely dissolve the gel from the vas deferens, reversing the male contraceptive.
More research must be done on the male contraceptive before the projected testing on human begins. The study was recently published in the journal Basic and Clinical Andrology.
By Cheryl Werber