The purpose of phase I trials is to gather initial data on a drug’s safety, not to test whether it’s effective. In fact, the duration of the trial was insufficient to prove the pill’s effectiveness as a contraceptive. That would take 60 to 90 days of use, the researchers said. Instead, the hormone changes seen in the volunteers were “consistent with effective contraception,” according to a news release.
The effects of the drug seemed to fade after the men stopped taking it.
Five men (17 percent) reported a mildly decreased sex drive. Two (7 percent) experienced mild erectile dysfunction although, according to a news release, “sexual activity was not decreased.”
Side effects included fatigue, acne or headache and were seen in four to six men each.
The drug, known as 11-beta-MNTDC, mimics testosterone. The study tested a base dose of 200 milligrams once daily in 14 people. Sixteen men got twice that dose. Another 10 received a dummy pill.
The team, led by Dr. Stephanie Page of the University of Washington School of Medicine in Seattle, is planning longer studies of the drug, also known as 11-beta-methyl-19-nortestosterone dodecylcarbonate.