Treatment of Endometriosis-Associated Pain with Elagolix



Title: Treatment of Endometriosis-Associated Pain with Elagolix, an Oral GnRH Antagonist

Taylor, HS, MD, et al.


 

What You Need to Know:

Treatment with lower and higher doses of elagolix, an oral, nonpeptide, gonadotropin-releasing hormone antagonist, improved dysmenorrhea and nonmenstrual pelvic pain in women with endometriosis-associated pain over 6 months compared to placebo.

Trial Design:

  • Two double-blind, randomized, phase 3 trials (Elaris EM-I and EM-II) evaluated the efficacy of high- and low-dose elagolix versus placebo in women with surgically diagnosed endometriosis and moderate or severe pain associated with endometriosis
  • 872 women were randomized to receive 150mg elagolix once daily (lower-dose group) or 200mg elagolix twice daily (higher-dose group) or placebo
  • Primary endpoints: proportion of patients achieving clinical response at 3 months with respect to dysmenorrhea and with respect to nonmenstrual pelvic pain
  • Clinical response measured by reduction in pain score and a reduction or consistent use of rescue analgesic medications
  • Secondary endpoints: average changes, from baseline, in the Numeric Rating Scale at 3 months, dysmenorrhea at 6 months, nonmenstrual pelvic pain at 6 months, use of analgesic medications at 3 and 6 months, and use of rescue opioids at 3 months

Key Outcomes:

  • 74.9% of patients (653/872) and 77.4% of patients (632/817) completed the intervention in Elaris EM-I and EM-II, respectively
  • Elaris EM-I: 46.4% of lower-dose elagolix patients and 75.8% of higher-dose elagolix patients achieved clinical response in regards to dysmenorrhea compared to 19.6% of placebo patients (P<0.001)
  • Elaris EM-II: 43.4% of lower-dose elagolix patients and 72.4% of higher-dose elagolix patients achieved clinical response in regards to dysmenorrhea compared to 22.7% of placebo patients (P<0.001)
  • Elaris EM-I: With respect to nonmenstrual pelvic pain, 50.4% of lower-dose elagolix and 54.5% of higher-dose elagolix patients achieved clinical response compared to 36.5% of placebo patients (P<0.001)
  • Clinical response was maintained at 6 months
  • Adverse events reported for elagolix patients include increased rates of hot flushes, increased serum lipids, and larger decrease in bone mineral density from baseline compared to placebo patients