A promising new birth control treatment -- for men, not women -- looks to be the future of contraception. It's safe, relatively uninvasive, 100 percent effective, and completely reversible. Developed by Prof. Sujoy K. Guha of the Indian Institute of Technology, the procedure called "Reversible Inhibition of Sperm Under Guidance," or RISUG, is currently in advanced clinical trials in India. Researchers hope to get Vasalgel (or "RISUG" in the Indian trials) on the market as a common alternative to vasectomy as early as 2015.
The treatment is similar to a vasectomy but it's more easily reversible. In a vasectomy, a small incision is made in the testicles and a surgeon severs either one or both vasa deferentia, which effectively prevents sperm from entering the seminal stream. In this new procedure, a doctor would inject a polymer gel called "Vasalgel" directly into the vas deferens instead of cutting it, which coats the walls of the duct and kills sperm as they go by.
The Male Contraception Information Project explains the polymer's benefits over a simple vasectomy:
"RISUG is composed of powdered styrene maleic anhydride (SMA, for which the method was previously named) combined with dimethyl sulfoxide (DMSO). Just enough of the resulting gel is injected into the vas deferens to coat the walls of the vas deferens and mostly block the lumen (passageway). However, RISUG does not rely on completely blocking the vas lumen for its effectiveness. The vas is a notoriously difficult tube to block completely, since it will often stretch around a plug and begin to leak - or if the plug is big enough that the vas can't stretch any farther, the vas may rupture. But RISUG is not just an inert plug; the RISUG material also actively kills any sperm that come near it. Therefore a smaller amount can be injected without worrying that leakage will make the method less effective. In fact, a small amount of leakage is actually a significant advantage, as it can reduce the pressure buildup that occurs with complete blockage."
Another advantage is the time it takes to become infertile: A vasectomy can take up to three months to clear sperm out of the system, while RISUG is effective almost immediately, but the best results come after waiting 72 hours. With one simple injection to each vas deferens, the patient only needs a band-aid over the small injection sites, and the man can go on his way. A single treatment can last for 10 or more years, and some patients in India have used it for more than 15 years.
Should the man want to reverse the treatment for any reason at all, the procedure can be reversed simply by flushing out the Vasalgel with another injection of DMSO, "a compound that is used in the medical treatment of many conditions and that is bioacceptable in the small quantities necessary." In summation, one gel restricts fertility and another one restores it.
The researchers in India have performed trials in animals (monkeys) and humans, and it has been a safe and effective treatment for 25 years. The studies tested dosage, length of action, reversibility, toxicity, and ultrastructural effects in the vas deferens before and after removal, as well as its effect on the prostate, sperm and semen. All studies have shown sperm returns to safe and normal conditions for offspring after the Vasalgel has been removed. However, in order to take Vasalgel outside of India, researchers need to start at the beginning and repeat RISUG studies.
"If all goes well with these preliminary steps, the next steps would be formal toxicology studies (researchers have already begun toxicology studies on rabbits). Then within 2012, there could be clinical trials of Vasalgel for United States men. Vasalgel could be on the U.S. market as early as 2015, although initially just as an alternative to vasectomy (later studies would be conducted to support reversibility rather than delaying initial rollout as a vasectomy alternative). The developers will then pursue approvals and affordable availability in countries around the world."
Parsemus Foundation, the nonprofit foundation sponsoring the research, says it needs $5 million for the entire development process, but the foundation is too small to raise the money alone. The company, therefore, says it needs "public awareness and support ... to be able to take on this new project."
"We are hopeful that new angel funders will appear who care enough about Vasalgel to specifically fund its development."
(Special thanks to Elaine Lissner, director of the Male Contraception Information Project.)
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