Dr. James Bradner of Dana-Farber Cancer Institute and Dr. Martin Matzuk of Baylor College of Medicine said the compound -- JQ1, originally synthesized at Dana-Farber to block BRD4, a cancer-causing gene -- penetrates the blood-testis boundary to disrupt spermatogenesis, the process by which sperm develop to become mature sperm.
This results in decrease in the number and quality of sperm, the researchers said.
The study, published in the journal Cell, showed normal sperm production resumed when JQ1 was discontinued, but JQ1 did not affect testosterone production, mating behavior or the health of offspring conceived after JQ1 use.
"Our findings demonstrate that, when given to rodents, this compound produces a rapid and reversible decrease in sperm count and mobility with profound effects on fertility," Bradner said in a statement. "These findings suggest that a reversible, oral male contraceptive may be possible. While we will be conducting more research to see if we can build on our current findings, JQ1 shows initial promise as a lead compound for male contraception."