Male contraceptive pill crosses the human clinical trial hurdle

By Dr. Ananya Mandal, MDMar 27 2019

Birth control pills have been around for the past six decades but have been for use of women only. A team of researchers this week have announced the success of the first male birth control pill that could safely prevent pregnancy.

Image Credit: Areeya Ann / Shutterstock

The findings of the study were presented on the 24th of March at ENDO 2019, the Endocrine Society's annual conference. The results of the study are published in The Journal of Clinical Endocrinology & Metabolism, Volume 104, Issue 3, March 2019.

The team announced that the new drug called 11-beta-MNTDC, has passed a 28-day trial with the volunteers experiencing no major side effects and there have been no drop-outs from the study. The new pill contains two hormones – the male testosterone and the female progestin. Dr. Christina Wang, the Associate director of the Clinical and Translational Science Institute at Los Angeles Biomed Research Institute (LA BioMed) explained that till date the pills that have been devised for men have caused an imbalance between these hormones in the body. This had led to effective contraception but in turn had caused lowering of libido. The pills had thus been unacceptable to the users. This new pill balances both hormones and thus the risk of lowered libido is not a possibility. Wang was part of the team from the University Of Washington School Of Medicine in Seattle that worked on developing this pill.

According to the researchers, once taken the two hormones separately work within the body. Progestin helps prevent production of the sperm and reduces the natural levels of testosterone or the male hormone. Lowering of testosterone normally can lead to lowered libido, depression, risk of blood clots and other side effects. This is balanced by the additional testosterone in the pill. Wang said in a statement, “We want [the hormones] to come on and decrease roughly together.” Professor of medicine at the University of Washington School of Medicine, Stephanie Page, in a statement said, “11-beta-MNTDC mimics testosterone through the rest of the body but is not concentrated enough in the testes to support sperm production.”

For this trial 40 participants were given pills of 200 (14 volunteers) or 400 milligrams (16 volunteers) of the active ingredient or a placebo pill (10 volunteers) for 28 days. The team was looking at the safety and tolerability of the drug rather than its efficacy is reducing the sperm count. Sperm count reduction takes 60 to 90 days of constant hormonal suppression, they explain. This study was thus designed to test the safety of the drug.

Results showed that none of the men showed side effects commonly seen due to very low levels of testosterone including depression and high blood pressure. Some side effects were however reported. This included acne in 22 patients, headaches, mild erectile dysfunction, tiredness, lowered sex drive and a weight gain of an average 2.8 or 4.2 pounds. Three taking placebo pills also exhibited these symptoms.

Wang added that long term effects of the pill are yet to be studied. At present lab animals have been administered these pills for three months or more and health effects on them are being studied before the pills can be given to humans for a longer period, the team explained. Wang said most men do not want to take a pill every day and ultimately the researchers aim to convert the pill into an injection that can be taken at regular intervals.

Dr Page said, “The goal is to find the compound that has the fewest side effects and is the most effective. We are developing two oral drugs in parallel in an attempt to move the (contraceptive medicine) field forward.”