James Bradner and his colleagues at Harvard's Dana-Farber Cancer Institute are working to create a molecule that can lead to the world’s first male birth control pill.
Bradner and his team accidentally stumbled upon the possible contraceptive when he was developing an inhibitor molecule that could make cancer cells forget they were cancer. It would lead to new treatments for blood and lung cancer. While in the process of developing the molecule, Bradner found that the molecule known as JQ1 could also inhibit a protein found in the testes that is essential to fertility.
"In mating studies, JQ1 accomplishes a complete and reversible contraceptive effect in males without adversely affecting testosterone levels or mating behaviors and without prompting obvious [birth defects]in offspring," Bradner and Martin Matzuk, of the Baylor College of Medicine wrote in their study.
JQ1is a small molecule that can easily move through blood stream into the testes. Once there, it binds to the protein BRDT, an important component of sperm production.
"These cells effectively forget how to make mature sperm," he said. "The result is a profound decrease in sperm count and impaired motility, leading to a complete contraceptive effect. It's really stunning."
Bradner said that once JQ1 is developed it can be administered through a pill, injection, or applied topically.
"As early as next year, we may have a sense of how well this works in humans," he said. "What was initially a side project in our laboratory has become a major focus of our research…we're still aggressively advancing a derivative of it as a cancer drug."
In the live mouse studies, the molecule effectively caused the mouse to be infertile. After the mouse was taken off the molecule for several weeks, he became fertile again with only one side effect.
"The only significant side effect we've seen has been mild weight loss," Bradner said. "For sure, some people would not be too upset with this."
Although birth control pills for women have been successfully administered for years, there has been no effective irreversible method proven to work for men. Previous attempts to develop a male birth control pill have resulted in adverse side effects. William Bremner of the University of Washington believes it’s easier to stop a woman’s ovulation process in comparison to keeping a man from developing over millions of sperm.
"The difficulty of fully suppressing these millions of spermatozoa produced daily compared to the relative ease of preventing the production of one ovum per month in the female," Bremner wrote in an article accompanying the new research.
Bradner and his team said that they will continue their molecule trials in dog studies until they can progress in making it available for humans. They hope to include the molecule in drugs that can be taken daily, weekly or monthly.
"We've yet to consider the ideal properties of this medication," Bradner said. "But we could very likely respond to the demands of men interested in this type of therapy."
