Home test kit confirms men's post-vasectomy sterility

Mar 12 2008

Technology developed at the University of Virginia could soon have a dramatic impact on male contraception practices throughout the U.S. Earlier this year, the U.S. Food and Drug Administration approved SpermCheck Vasectomy, a home test that confirms men's post-vasectomy sterility and is based on discoveries made at U.Va.

SpermCheck Vasectomy is one of several products founded on technology developed by John C. Herr, director of U.Va.'s Center for Research in Contraceptive and Reproductive Health, and patented and licensed by the U.Va. Patent Foundation.

"The SpermCheck Vasectomy test is the result of many years of basic science research coupled with clinical chemistry know-how," said Herr, a professor in U.Va.'s Department of Cell Biology, citing interdisciplinary clinical collaborations with Drs. Stuart S. Howards, professor of urology, and Charles J. Flickinger, professor emeritus of cell biology. "Similar to a home pregnancy test for women, it is the first immunodiagnostic test with the sensitivity and specificity required to detect low numbers of sperm, and it is the first immunodiagnostic test to receive FDA approval for monitoring sperm count after vasectomy."

The device gives men an opportunity to test their post vasectomy fertility status at home rather than return to the physician's office or a laboratory with semen samples, as has traditionally been required to confirm sub-fertile sperm levels.

"We are very excited that one of our faculty start-ups is about to introduce its first product to the market," said Robert S. MacWright, executive director of the U.Va. Patent Foundation. "Through an enlightened and balanced integration of basic science and practical application in his research, Dr. Herr is delivering important scientific knowledge that is truly serving the public good."

Approximately 500,000 men undergo vasectomies in the U.S. each year, making vasectomy the third-most-popular contraceptive option among married couples in the U.S., according to the National Institutes of Child Health and Human Development, a division of the National Institutes of Health. Also according to the NIH, one in six men over age 35 have had a vasectomy.

It is widely reported that vasectomies are not 100 percent effective, and vasectomized men can experience recanalization, or the spontaneous healing or restoration of the vas deferens resulting in fertility. SpermCheck Vasectomy, to be made available as soon as spring 2008 by ContraVac Inc., can be used to monitor and confirm sterility following the vasectomy procedure, alerting couples should fertility become restored. In addition, Herr posits, the device could be used to monitor male infertility over time in the event that male contraceptive pills are successfully developed.

Over 17 years, Herr's lab worked to identify a gene (ACRV1) that encoded a protein that could serve as a sperm-specific biomarker. This protein - SP-10 - is very soluble and highly expressed, making it an ideal target for diagnostic testing, as in the SpermCheck Vasectomy home-use test developed by U.Va. start-up ContraVac Inc. The device uses monoclonal antibodies that bind specifically to the SP-10 protein to measure the amount in nanograms of SP-10 protein present, which directly correlates to the number of sperm present.

"Translational research is essential to bringing the exciting new developments in basic-science biomedical research to patients," Howards says. "The outcome of an intense collaboration between basic science and clinical urology, SpermCheck Vasectomy is an example of translational research 20 years in the making."