Introduction: The Women's Health Initiative Estrogen Plus Progestin clinical trial demonstrated the risks exceeded the benefits which have led to a decline in menopausal hormone therapy (MHT) by greater than 50%. MHT use was initiated long before there was a significant understanding of the molecular mechanisms of estrogens. It has become clear that the problem with the current estrogens in MHT is they act non-selectively as an agonist in all tissues that contain estrogen receptors. MF101 is an oral, botanically derived extract that was designed to selectively regulate estrogen receptor beta (ER beta) because the increased risk of breast and endometrial cancer is due to the activation of estrogen receptor alpha (ER alpha) by estrogens. Preclinical and clinical data support a role for selective ER beta agonists, such as MF101, for vasomotor symptoms without increasing cancer risks. Areas covered: The review covers the biological, pharmacological and clinical advantages of MF101, and the unique ability of MF101 to selectively target the ER beta pathway for the treatment of hot flashes (HF). Expert opinion: Preclinical and clinical studies indicate that MF101, a selective estrogen receptor beta agonist, represents a new class of drugs that is safe and effective for treating HF and nighttime awakenings.
