New cancer drug may point way to male birth control pill
Published Friday, August 17, 2012 11:58AM EDT
Last Updated Friday, August 17, 2012 11:59AM EDT
While women have multiple birth control options available on the pharmacy shelf, men have traditionally been restricted to the condom as their only baby blocker option.
That may be about to change, with a new study showing a drug originally developed to treat cancer has the ability to inhibit sperm cell activity and may point the way to a male form of contraception.
And once the study subjects went off the drug, known as JQI, the sperm return to their full strength with no side effects, according to the study on mice.
"When male mice are exposed to JQI in a healthy dose of 50 milligrams per kilogram, we observed a dose and time-dependent decrease in numerous parameters associated with fertility," said James Bradner, the senior author on the study and an assistant professor at Harvard Medical School.
The study is published in the journal Cell.
The results showed no major toxic effects in other critical tissues in the body, with the drug directly targeting BRDT – a protein in the testicles that is required for fertility to occur.
The result is a reduction in the number of sperm cells and the impairment of those that remained.
"We performed a number of mating studies in the course of these experiments and it is unambiguous that mice receiving JQI at a low or high dose regimen...are infertile after one to two months of therapy and as they remain on JQI their infertility persists," Bradner said in a video on the Cell website.
However, after the JQI treatment was stopped, the male mice once again became fertile.
"And in fact the male mice go on to sire pups in litters of normal sizes and importantly, animals with no overt...abnormalities," Bradner said.
Unlike other attempts at developing a male contraceptive, the drug does not target hormone levels and in fact had no effect on the testosterone levels of the male mice.
JQI, which has not yet been tested on humans, was initially developed to block a gene connected with lung and blood cancers.