Early research suggests that mifepristone, a drug commonly used for medical abortions, may also help reduce breast cancer risk by slowing abnormal cell growth in breast tissue. However, its association with abortion has created significant obstacles for further study and development as a potential cancer prevention treatment.
According to a recent Lancet viewpoint, three small preclinical studies found that mifepristone inhibits progesterone, a hormone that drives breast cell proliferation—particularly in high-risk patients, such as those with BRCA gene mutations. Currently, women at elevated risk face limited options, including preventive mastectomies or estrogen-blocking drugs, which often cause severe side effects.
Despite its potential, pharmaceutical companies have been reluctant to invest in mifepristone research due to its controversial use in abortion. Additionally, restrictive abortion laws in some countries limit access to the drug altogether, further stifling progress.
The authors argue that political and social stigma should not prevent scientific exploration of mifepristone’s life-saving potential. They call for urgent funding and policy support to advance clinical trials.
“Breast cancer is the leading cause of cancer deaths in women worldwide,” the researchers noted. “We cannot afford to ignore a promising preventive option because of unrelated controversies.”
Further studies are needed to confirm mifepristone’s safety and effectiveness in cancer prevention, but without broader institutional support, progress remains stalled.