SAN DIEGO, Aug. 29, 2013 /PRNewswire/ -- Neurocrine Biosciences, Inc. (NASDAQ:NBIX) today announced that the second Phase III pivotal trial to evaluate elagolix for the treatment of endometriosis has been initiated by AbbVie. This second Phase III trial is similar in design to the initial Phase III trial which is scheduled to provide top-line data in the third quarter of 2014 and complete in 2015. "We are pleased that the second Phase III study in endometriosis has been launched," said Kevin C. Gorman, President and Chief Executive Officer of Neurocrine Biosciences. "The two Phase III trials will serve as the foundation for the anticipated NDA filing which is on track for 2016." The second Phase III trial is a 24-week multinational, randomized double-blind, placebo-controlled study designed to evaluate the safety and efficacy of elagolix in 788 women, age 18-49, with moderate-to-severe endometriosis-associated pain. It will be conducted at more than 200 sites globally . Elagolix is an oral gonadotropin-releasing hormone (GnRH) antagonist, in development by AbbVie for the treatment of uterine fibroids and endometriosis. Neurocrine and AbbVie entered into a collaboration and license agreement for elagolix during 2010. 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 Elagolix Elagolix inhibits gonadotropin 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. At the time of expected NDA filing for endometriosis, elagolix will have been studied in over 25 clinical trials and in excess of 3,000 subjects. A Phase IIb trial of elagolix for the treatment of uterine fibroids is also ongoing.