Until now, contraception (hormonal or nonhormonal) has mainly been the responsibility of women, even if it means at times carrying a condom. Researchers at the University of Virginia School of Medicine have discovered a way to produce an enzyme found in sperm that’s involved in its motility, or ability to move. This can lead to several studies that can produce drugs that can stop sperm right in its tracks and never reach the egg, thus preventing fertilization and pregnancy. The enzyme is normally found in the testes, and if they can figure out how to bind other molecules around the enzyme’s binding sites to where its function is decreased it could lower sperm production and motility.
Dr. John Herr, one of the researchers and director of UVA’s Center for Research in Contraceptive and Reproductive Health, did elaborate on the challenge of developing a male contraceptive pill that has the unique and precise mechanism of targeting the testicular enzyme, but not affect any other system in the body. This testis-specific serine/threonine kinase 2 (TSSK2) enzyme is now offering that pharmacological approach to contraception in the form of kinase inhibitors, as long as they are able to localize the activity to the testes alone. TSSK2 is found in both the spermatids (precursor to sperm) as well as the ejaculated sperm. It is also associated in development of the sperm’s flagellum (the whip like structure that enables movement). The approach of kinase inhibitors has been used in the past to fight diseases like leukemia but has yet to be used in the novel approach of male contraception. There’s plenty of opportunity for drugs to be developed for the many binding sites around the enzyme, but emphasis needs to be placed on the fact that this drug is to be administered to healthy males, and needs to have little to no side effects. That being said, this will be as welcome of a development as this research group’s previous achievement in developing SpermCheck, a home fertility test for men sold around the world.