Kevin Eisenfrats

There are only a few ways that men who have sex with women can prevent pregnancies: Wear a condom, or get a vasectomy. But condoms are only about 87% effective, and vasectomies aren’t recommended for men who may later want children. 

Kevin Eisenfrats, 32, has been thinking about this problem since high school, when he saw an episode of the MTV show “16 and Pregnant.” He thought, if men had better forms of birth control, more of them would use it—and there’d be fewer unintended pregnancies. 

In 2015, a few months before he graduated from the University of Virginia’s engineering school—where he was mentored by the late professor John Herr, whose lab focused in part on finding novel approaches to contraception—Eisenfrats launched his own company, Contraline. Its first product is called ADAM: a long-lasting hydrogel that could be injected into the vas deferens (a channel that sperm flows through on its way from the testicles to the penis) to stop sperm from escaping. 

That product has now been tested for safety and efficacy in a small human trial in Australia, and proven effective at blocking sperm in three men for up to two years. Contraline will soon begin a larger phase 2 trial in Australia that will, crucially, determine if the gel can be easily removed, with fertility restored soon after. 

Meanwhile, Eisenfrats is expanding Contraline’s portfolio. A year ago, his company signed an exclusive licensing agreement with the nonprofit research organization Population Council, which has historically focused on reproductive health, for the right to finish developing and then market another contraception for men, known as NES/T. It’s a hormonal gel that men can rub on their shoulders every day to reduce their sperm production enough to prevent pregnancies. NES/T has already been tested in hundreds of patients in clinical trials led by the Population Council, with support from the National Institutes of Health. Contraline will begin phase 3 trials—the final step before seeking FDA approval—next year. 

Eisenfrats is currently raising $65 million from investors and hopes to expand his team of about 20 employees. If all goes well, Eisenfrats expects both products will be available by 2030.