A sperm-slowing male contraceptive has proven to work in tests with monkeys without affecting hormones, so could this potentially be the next safe and effective form of birth control?
The evidence is promising.
Researchers who conducted a study and published their findings Friday in the journal PLOS ONE, found that experimental compound EP055 successfully bound to sperm proteins to slow their mobility.
"Simply put, the compound turns off the sperm's ability to swim, significantly limiting fertilization capabilities," lead investigator Michael O'Rand, a retired professor of cell biology and physiology at the University of North Carolina, said in a statement. "This makes EP055 an ideal candidate for non-hormonal male contraception."
The study saw high doses of EP055 administered to monkeys and, after six hours, researchers found that sperm motility fell to 20 percent, UPI noted.
After 30 hours, the team reported no normal sperm activity among the monkeys but, after administering an injection, sperm activity recovered to pre-test levels.
During the trial, no physical symptoms were recorded and, while researchers feel more work is needed before EP055 becomes available for human use, they are positive of their findings.
Currently, the only contraceptive options available for men are condoms and vasectomy and, while there are hormonal drugs in clinical trials targeting sperm production, they affect hormonal levels.
With EP055, the test monkeys showed "signs of complete recovery" at 18 days post-infusion, "suggesting that the EP055 compound is indeed reversible," said study co-investigator Mary Zelinski, a research associate professor at the ONPRC at OHSU.
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