Mifepristone as Weekly Contraceptive Shows Promising Results in Clinical Trials

Dr. Rebecca Gomperts has announced preliminary results from a significant clinical trial in Moldova, indicating that a 50 mg dose of mifepristone is highly effective as a weekly contraceptive pill. 'The outcome so far is beyond expectations,' said Gomperts, noting only one pregnancy among 2,000 cycles of unprotected intercourse, which occurred in a participant already pregnant before starting the medication.

Conducted by Women on Waves in collaboration with Karolinska Institutet and Leiden University Medical Center, the trial adhered to the stringent requirements of the European Medicine Agency and the U.S. Food and Drug Administration. Only 4 percent of participants reported minor side effects, such as headaches and hot flashes, significantly lower than the 40 percent associated with hormonal contraceptives.

Mifepristone offers a flexible contraceptive option, differing from traditional hormonal methods that require daily intake. 'If you forget mifepristone one day and use it the next, it will still work,' Gomperts explained, highlighting its reliability and ease of use. The drug works by blocking progesterone receptors, preventing the endometrium from maturing in a way that allows a fertilized egg to implant.

Eighty-nine percent of participants stopped menstruating, a side effect Gomperts described as positive for many. The trial's success paves the way for further studies in the Netherlands, with hopes of obtaining European Medicines Agency approval for mifepristone as a weekly contraceptive.

Gomperts emphasized the importance of making mifepristone available as a contraceptive, noting its potential to change how women worldwide control their fertility. 'It would allow us to move flexibly between the medicine’s different indications,' she said, advocating for its use as a weekly contraceptive, an on-demand method, or an early medical abortion method.

The study also explores mifepristone's broader potential, including its effectiveness against endometriosis and myoma, and its possible role in preventing breast cancer. Gomperts is committed to ensuring mifepristone's availability at an affordable price, aiming for open-source distribution to make it accessible globally, especially in low and middle-income countries.