Elagolix – GnRH Antagonist

GnRH is a peptide that stimulates the secretion of the pituitary hormones that are responsible for sex steroid production and normal reproductive function. Elagolix is a novel, orally administered gonadotropin-releasing hormone (GnRH) antagonist. Elagolix is believed to have its effect by altering the level of pituitary GnRH suppression and, as a result, titrating circulating hormone levels. By this method, it is believed that elagolix may provide relief from the pain associated with conditions such endometriosis and uterine fibroids, without a need to actively manage bone loss.

Elagolix is currently being investigated in both patients with endometriosis and those with uterine fibroids.


In June 2010, we announced an exclusive worldwide collaboration with AbbVie to develop and commercialize elagolix and all next-generation GnRH antagonists (collectively, GnRH Compounds) for women’s and men’s health. Under the terms of our agreement with AbbVie, we and AbbVie will work jointly to advance GnRH Compounds towards commercialization. Abbott made an upfront payment of $75 million and agreed to make additional development and regulatory event based payments of up to $480 million and up to an additional $50 million in commercial event based payments. Under the terms of the agreement, AbbVie is responsible for all development, marketing and commercialization costs. We will be entitled to a percentage of worldwide sales of GnRH Compounds for the longer of ten years or the life of the related patent rights.


The Phase I and II data for elagolix in women support the potential for use in other women’s health conditions.  Menorrhagia (excessive uterine bleeding) and primary dysmenorrhea commonly result from underlying endometriosis, uterine fibroids or adenomyosis and, as such, may be amenable to treatment with a nonpeptide GnRH antagonist.  Current peptide antagonists are commercially available for prevention of premature luteinizing hormone (LH) surge as part of Assisted Reproductive Therapy.  Oral GnRH antagonists could reduce the burden of injections for women undergoing these procedures. Potential other women’s health indications include premenstrual dysphoric disease (PMDD), polycystic ovarian syndrome (PCOS), breast cancer prevention, and precocious puberty.