First analysis of FDA’s mifepristone adverse event reports

The abortion drug mifepristone (Mifeprex,TM RU-486), initially touted as a more convenient alternative to surgical abortion, has been linked to serious adverse reactions, including several deaths in otherwise healthy women. In “Analysis of Severe Adverse Events Related to the Use of Mifepristone as an Abortifacient,” researchers Margaret M Gary MD and Donna J Harrison MD provide an in-depth study of mifepristone adverse event data gathered through the FDA’s Adverse Event Reporting System. Their research is available now at The Annals of Pharmacotherapy Online and will appear in the journal’s February issue.

This first published analysis of the FDA’s mifepristone reports describes 607 adverse events reported over a 4-year period, including fatalities resulting from bleeding or septic shock. Also reviewed are numerous reports of severe bleeding, infection, unsuccessful termination of pregnancy, and fetal malformations that appeared after failed abortion attempts. Reports also detail ruptured ectopic pregnancies, a potentially fatal condition requiring emergency surgical intervention. Unusual allergic reactions were also noted, which Gary and Harrison suspect may have resulted directly from the drug’s mechanism of action.

Prompted by their findings, the authors call for increased research into the allergic and fatal septic reactions associated with mifepristone. They also urge that ultrasound imaging be performed before use of the drug to rule out ectopic pregnancies and propose that a fetal registry be established to track birth defects in mifepristone survivors. Finally, incomplete information in many of the adverse event reports prompts Gary and Harrison to speculate on whether the FDA’s Adverse Event Reporting System adequately identifies risks and protects public health.

At least 5 women in the US and Canada are known to have died from septic shock after taking mifepristone. In 2004, the labeling of mifepristone was amended to include a black box warning about bacterial infections, sepsis, and death that may occur after use. A citizen petition for withdrawal of mifepristone from the US market has been submitted to the FDA. The petition cites numerous safety concerns and FDA procedural violations that occurred during the drug’s approval.