An investigational oral synthetic androgen shows promise as a potential male contraceptive pill, after a new month-long study. 

Dose-finding and safety results of the trial in 82 healthy men were presented at ENDO 2018: The Endocrine Society Annual Meeting by Arthi Thirdumalai, MBBS, acting assistant professor, University of Washington, Seattle. 

“It only needs to be dosed once a day, and we didn’t see any significant side effects, but it needs to be tested much longer. This is a very early phase,” explained coauthor Stephanie Page, professor of medicine at the university. 

During a press briefing, Page showed data from a multinational survey in which 60% to 80% of men indicated that they would be interested in a reversible male contraceptive if one were available, and of those, more than 30% prefer a daily pill over injected formulations.

“Many men say they would prefer a daily pill as reversible contraceptive, rather than long-acting injections or topical gels, which are also in development,” she added. “I think the landscape has changed and the interest in male contraception is really growing.” 

The agent, dimethandrolone undecanoate (DMAU), is a prodrug that is converted to dimethandrolone (DMA), which binds to both androgen and progesterone receptors. The long-chain fatty acid component undecanoate slows the drug’s clearance, enabling the one-daily dosing. 

So far, efforts to develop a male contraceptive have been challenging due to the potential for hepatoxicity and need for multiple daily dosing. “DMAU is very different…We hope it’s a big step forward. These promising results are unprecedented in the development of a prototype male pill,” added Page. 

However, Alberto Ferlin, associate professor of endocrinology at the University of Brescia, Italy, and president of the Italian Society of Andrology and Sexual Medicine argued, “It’s very interesting because in one pill you have both the function of contraception but apparently no symptoms of testosterone.” 

He cautioned that the data is short-term and very preliminary. “We should wait for a longer treatment period to see if the men develop consequences of low testosterone on lipids, glucose metabolism, and bone health. Most important for contraception is the sperm count needs to go down…If it goes down but not completely, there’s still the possibility of pregnancy.”

Page went on to confirm at the press briefing that the research team had begun a three-month study to establish safety and sperm suppression. 

“We’re confident, but this [current] study was too short. Ultimately, we need to do a study with couples. There’s lots of work to do.”

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