ABBOTT PARK, Ill., June 5, 2012 /PRNewswire/ -- Abbott (NYSE: ABT), in cooperation with Neurocrine Biosciences, Inc. (NASDAQ: NBIX), today announced the initiation of a pivotal Phase 3 clinical trial designed to evaluate the safety and efficacy of elagolix in female patients with endometriosis. Elagolix is an oral gonadotropin-releasing hormone (GnRH) antagonist. "Endometriosis can be a debilitating disease that affects millions of women around the world and the exploration of new treatments could offer other options for women with this disease," said Dr. Hugh Taylor, M.D., Chief of Division of Reproductive Endocrinology and Infertility, Yale School of Medicine. The Phase 3 trial (M12-665) is a 24-week, multinational, randomized, double-blind, placebo-controlled study designed to evaluate the safety and efficacy of elagolix in 875 women, age 18 to 49, with moderate-to-severe endometriosis-associated pain. It will be conducted at approximately 160 sites in the United States, Puerto Rico and Canada. "The investigation of elagolix for endometriosis is an important step in the exploration of potential treatments for this underserved patient population," said Rita Jain, M.D., divisional vice president, Pain, Respiratory and Metabolic Development, Global Pharmaceutical R&D, Abbott. "We are pleased to announce that the Phase 3 trial has begun screening for enrollment." A second pivotal Phase 3 study is planned with an NDA filing targeted in 2016. About Elagolix Elagolix inhibits gonadatropin releasing hormone (GnRH) receptors in the pituitary gland and ultimately reduces circulating sex hormone levels. To date, elagolix has been studied in over 20 clinical trials totaling more than 1,000 subjects. A Phase 2a trial of elagolix for the treatment of uterine fibroids is also ongoing. About Endometriosis Endometriosis is associated with a multitude of symptoms, some of the most common of which include pain related both to menstruation (dysmenorrhea) as well as chronic pelvic pain throughout the menstrual cycle, and is a leading cause of infertility. The World Endometriosis Research Foundation estimates that there are approximately 100 million women worldwide who suffer from endometriosis. The annual direct and indirect costs of endometriosis are estimated to exceed $20 billion in the United States alone. About Abbott Abbott is a global, broad-based health care company devoted to the discovery, development, manufacture and marketing of pharmaceuticals and medical products, including nutritionals, devices and diagnostics. The company employs approximately 91,000 people and markets its products in more than 130 countries.