AbbVie in cooperation with Neurocrine Biosciences announced that the Phase 3 ELARIS UF-II study (M12-817) of elagolix met its primary endpoint. Results from the second of two pivotal Phase 3 studies demonstrated at month six that elagolix (300 mg twice daily), in combination with low-dose hormone (add-back) therapy (estradiol 1.0 mg / norethindrone acetate 0.5 mg), reduced heavy menstrual bleeding with 76.2 percent (p<0.001) of women with uterine fibroids achieving clinical response compared to placebo (10.1 percent), as measured by the alkaline hematin method. Clinical response was defined as menstrual blood loss volume of less than 80 mL during month six and a 50 percent or greater reduction in menstrual blood loss volume from baseline to month six. The study also met all ranked secondary endpoints (p<0.02) at month six.

Uterine fibroids are the most common type of abnormal growth in a woman's pelvis and can affect up to 80 percent of women by age 50.2 Fibroids can be asymptomatic, but in approximately 25 percent of women3, fibroids can cause symptoms, such as heavy menstrual bleeding, painful periods, vaginal bleeding at times other than menstruation, and anemia. African American women are more likely to experience fibroids and do so at a younger age.
"Millions of women currently diagnosed with uterine fibroids are faced with limited non-surgical options," said Dawn Carlson, M.D., M.P.H., vice president, general medicine development. "The results from this study demonstrate elagolix has the potential to be an important oral treatment option for women suffering from uterine fibroids."
Hypoestrogenic effects, such as hot flush and reduction in bone mineral density, from elagolix treatment were observed in the study. The overall safety profile for elagolix was consistent with what was observed in Phase 2 studies and the first Phase 3 study (ELARIS UF-I) in uterine fibroids. Data from the ELARIS UF-II Phase 3 study will support regulatory submissions for elagolix. Safety data, including most common adverse events, continue to be collected in this ongoing study.
The topline results from this six-month primary analysis were consistent with topline results from the ELARIS UF-I study reported in February 2018 and will be presented at an upcoming medical conference. Women in the study will continue in either post-treatment follow-up or a blinded six-month extension study.
Uterine fibroids (also called leiomyomas or myomas) are non-cancerous, hormonally-responsive muscle tissue tumors of the uterus. Fibroids are the most common type of abnormal growth in a woman's pelvis and can affect about 20-80 percent of women by age 50. Fibroids can range in size, shape, number and location. Fibroids can be asymptomatic, but in some women, fibroids can cause symptoms such as heavy menstrual bleeding, painful periods, vaginal bleeding at times other than menstruation, anemia, pain in the abdomen or lower back, pain during sex, difficulty urinating or frequent urination, constipation, rectal pain or difficulty getting pregnant. Treatment options for uterine fibroids include surgery (hysterectomy, myomectomy), hysteroscopy, endometrial ablation, uterine artery embolization, magnetic resonance imaging-guided ultrasound and medical management with treatments such as oral contraceptives, progestins, selective progesterone receptor modulators, and GnRH agonists, some of which are not specifically indicated for the treatment of uterine fibroids.