Treatment of Endometriosis-Associated Pain with Elagolix, an Oral GnRH Antagonist
Hugh S Taylor1, Linda C Giudice1, Bruce A Lessey1
1From Yale School of Medicine, New Haven, CT (H.S.T.); University of California, San Francisco, San Francisco (L.C.G.); Greenville Health System, Greenville, SC (B.A.L.); University of São Paulo and Sirio Libanes Hospital, São Paulo (M.S.A.); Medical University, Lublin, Poland (J.K.); Eastern Virginia Medical School, Norfolk (D.F.A.); Augusta University, Augusta, GA (M.P.D.); Colorado Center for Reproductive Medicine, Lone Tree (E.S.); Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia (N.P.J.); Repromed Auckland, Auckland, New Zealand (N.P.J.); Mercy Health Osteoporosis and Bone Health Services, Cincinnati (N.B.W.); Creighton University School of Medicine, Omaha, NE (J.C.G.); George Washington University, Washington, DC (J.A.S.); University of Texas Southwestern Medical Center, Dallas (B.C.); Institute for the Study and Treatment of Endometriosis, Oak Brook (W.P.D.), and AbbVie, North Chicago (J.P.R., W.R.D., J.N., B.S., J.W.T., R.I.J., K.C.) - both in Illinois; and McMaster University, Hamilton, ON, Canada (N.L.).
Background:
Endometriosis is a chronic, estrogen-dependent condition that causes dysmenorrhea and pelvic pain. Elagolix, an oral, nonpeptide, gonadotropin-releasing hormone (GnRH) antagonist, produced partial to nearly full estrogen suppression in previous studies.
Methods:
We performed two similar, double-blind, randomized, 6-month phase 3 trials (Elaris Endometriosis I and II [EM-I and EM-II]) to evaluate the effects of two doses of elagolix - 150 mg once daily (lower-dose group) and 200 mg twice daily (higher-dose group) - as compared with placebo in women with surgically diagnosed endometriosis and moderate or severe endometriosis-associated pain. The two primary efficacy end points were the proportion of women who had a clinical response with respect to dysmenorrhea and the proportion who had a clinical response with respect to nonmenstrual pelvic pain at 3 months. Each of these end points was measured as a clinically meaningful reduction in the pain score and a decreased or stable use of rescue analgesic agents, as recorded in a daily electronic diary.
Results:
A total of 872 women underwent randomization in Elaris EM-I and 817 in Elaris EM-II; of these women, 653 (74.9%) and 632 (77.4%), respectively, completed the intervention. At 3 months, a significantly greater proportion of women who received each elagolix dose met the clinical response criteria for the two primary end points than did those who received placebo. In Elaris EM-I, the percentage of women who had a clinical response with respect to dysmenorrhea was 46.4% in the lower-dose elagolix group and 75.8% in the higher-dose elagolix group, as compared with 19.6% in the placebo group; in Elaris EM-II, the corresponding percentages were 43.4% and 72.4%, as compared with 22.7% (P<0.001 for all comparisons). In Elaris EM-I, the percentage of women who had a clinical response with respect to nonmenstrual pelvic pain was 50.4% in the lower-dose elagolix group and 54.5% in the higher-dose elagolix group, as compared with 36.5% in the placebo group (P<0.001 for all comparisons); in Elaris EM-II, the corresponding percentages were 49.8% and 57.8%, as compared with 36.5% (P=0.003 and P<0.001, respectively). The responses with respect to dysmenorrhea and nonmenstrual pelvic pain were sustained at 6 months. Women who received elagolix had higher rates of hot flushes (mostly mild or moderate), higher levels of serum lipids, and greater decreases from baseline in bone mineral density than did those who received placebo; there were no adverse endometrial findings.
Conclusions:
Both higher and lower doses of elagolix were effective in improving dysmenorrhea and nonmenstrual pelvic pain during a 6-month period in women with endometriosis-associated pain. The two doses of elagolix were associated with hypoestrogenic adverse effects. (Funded by AbbVie; Elaris EM-I and EM-II ClinicalTrials.gov numbers, NCT01620528 and NCT01931670 .).
Related Concept Videos
Drugs for Treatment of Diarrhea-Predominant IBS
Two specific drugs used in the treatment are alosetron (Lotronex) and eluxadoline (Viberzi). Alosetron, a 5-HT3 antagonist, works by slowing the movement of stools in the gut, reducing bowel...
Drugs for Treatment of Constipation-Predominant IBS
Peptic Ulcer Disease IV: Management
The therapeutic approach involves ensuring adequate rest, implementing drug therapy, promoting smoking cessation, making dietary modifications, and emphasizing long-term follow-up care.
Pharmacological management
The prevailing therapy for peptic ulcers involves a combination of managing the patient's current...
Treatment for Pulmonary Arterial Hypertension: Endothelin Receptor Antagonists
ETs are synthesized through a complex sequence of enzymatic steps, primarily involving an enzyme referred to as endothelin-converting enzyme...
Analgesia and Pain Management


