Male birth control found safe and successful in preventing pregnancy in rhesus monkey models
Orange County, CA -
March 30th 2017 - In the United States, 45% of all pregnancies are unintended, a rate significantly higher than that of other developed countries. Currently there are only two male contraceptive options to the public; condoms and vasectomy, with the latter meant to be permanent. The lack of affordable long-acting contraceptive options for men makes the likelihood of an unintended pregnancy higher and makes women disproportionately responsible for a result that takes two. With public expenditures on unintended pregnancies in the US at an estimated $21 billion, a solution is vital. To help bring a long-acting reversible contraceptive, Parsemus Foundation, a non-profit organization based in Berkeley, California, developed Vasalgel. Vasalgel is a polymer with a high molecular weight made up of styrene-alt-maleic acid dissolved in dimethyl sulfoxide. After injecting the polymer into the vas deferens, or the duct that conveys sperm from the testicle to the urethra, it becomes a hydrogel. That gel then blocks the passage of sperm, without blocking other fluids, making it non-hormonal. These other liquids are able to pass through the gel at a slower rate, but reduce effects noted in vasectomy like back-pressure on the epididymis. In rabbit models, to reverse the effects of the gel, a simple sodium bicarbonate solution was used to flush it out of the system. Sperm flow was said to quickly resume.
March 30th 2017 - In the United States, 45% of all pregnancies are unintended, a rate significantly higher than that of other developed countries. Currently there are only two male contraceptive options to the public; condoms and vasectomy, with the latter meant to be permanent. The lack of affordable long-acting contraceptive options for men makes the likelihood of an unintended pregnancy higher and makes women disproportionately responsible for a result that takes two. With public expenditures on unintended pregnancies in the US at an estimated $21 billion, a solution is vital. To help bring a long-acting reversible contraceptive, Parsemus Foundation, a non-profit organization based in Berkeley, California, developed Vasalgel. Vasalgel is a polymer with a high molecular weight made up of styrene-alt-maleic acid dissolved in dimethyl sulfoxide. After injecting the polymer into the vas deferens, or the duct that conveys sperm from the testicle to the urethra, it becomes a hydrogel. That gel then blocks the passage of sperm, without blocking other fluids, making it non-hormonal. These other liquids are able to pass through the gel at a slower rate, but reduce effects noted in vasectomy like back-pressure on the epididymis. In rabbit models, to reverse the effects of the gel, a simple sodium bicarbonate solution was used to flush it out of the system. Sperm flow was said to quickly resume.
After studying rabbit models, the team moved on to a larger mammal, the rhesus monkey. Their results have been published in Basic and Clinical Androlog.
Sixteen adult male rhesus monkeys were injected with Vasalgel before being placed in outdoor group housing with 3-9 females with a healthy reproductive history. All of the males were observed for at least one breeding season and 7 of the 16 males were housed with females at nearly all times.
The results indicate that there were no conceptions after injection of Vasalgel.
“Intravas injection of Vasalgel in sexually mature adult male rhesus monkeys was effective in preventing conception in a free-living, group environment,” stated the authors in their study. “Complications were few and similar to those associated with traditional vasectomy.”
After collecting substantial evidence proving the gels success in both rabbits and monkeys the next steps for the research team is to begin human trials. Preparations are already in motion for multiple studies, the first is to explore Vasalgel’s effectiveness in humans, and the subsequent studies will be in the reversal of the gels effects.
