Elagolix Treatment for Endometriosis-Associated Pain: Results from a Phase 2, Randomized, Double-Blind, Placebo-Controlled Study

Michael P Diamond, Bruce R. Carr, Bruce Carr, W Paul Dmowski, William Koltun, C. F. O'Brien, Chris O'Brien, Ping Jiang, Joshua Burke, Roland Jimenez, Elizabeth Garner, Kristof Chwalisż, Kristof Chwalisz
Reproductive sciences (Thousand Oaks, Calif.) · 2013 · vol. 21(3) , pp. 363–371 · doi:10.1177/1933719113497292 · PMID:23885105 · W2101288911
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⚙ AI-generated summary by claude@2026-06+body, 2026-06-07 ⓘ

This Phase 2 study found elagolix reduced dysmenorrhea pain versus placebo but not overall pain, with minimal bone density changes.

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⚙ AI-generated deep summary by claude@2026-06, 2026-06-07 · read from full text ⓘ

This Phase 2 randomized, double-blind, placebo-controlled study evaluated the safety and efficacy of the oral GnRH antagonist elagolix in 155 women with laparoscopically confirmed endometriosis-associated pain, comparing placebo with elagolix 150 mg or 250 mg once daily for 12 weeks (with placebo patients rerandomized to elagolix and original elagolix patients continuing for an additional 12 weeks). At week 12, monthly mean reductions in pain score were greater with elagolix than placebo, but the between-group differences were not statistically significant; dysmenorrhea and nonmenstrual pelvic pain scores were reduced, with significant dysmenorrhea differences versus placebo at weeks 8 and 12. Minimal bone mineral density changes were observed. The paper’s key caveat is that the primary efficacy endpoint did not show statistically significant differences versus placebo. This paper is centrally about endometriosis — it tests elagolix for endometriosis-associated pain and reports the Phase 2 efficacy and safety outcomes.

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Abstract

This Phase 2 study evaluated the safety and efficacy of elagolix for treating endometriosis-associated pain. A total of 155 women with laparoscopically confirmed endometriosis were randomized to placebo, elagolix 150 mg, or elagolix 250 mg once daily for 12 weeks. Placebo patients were rerandomized to elagolix and elagolix patients continued their dosing assignment for 12 additional weeks; the primary efficacy measure was changed from baseline in the monthly mean numerical rating scale for pain at week 12. Monthly mean (standard error of the mean) reductions were greater with elagolix versus placebo (−1.19 ± 0.18, −1.25 ± 0.18, and −0.88 ± 0.18 for elagolix 150 mg, 250 mg, and placebo, respectively); differences were not statistically significant. Monthly mean dysmenorrhea and nonmenstrual pelvic pain scores were reduced with elagolix, with significant differences for dysmenorrhea at weeks 8 and 12 versus placebo (P <.05). Minimal bone mineral density changes were observed with elagolix treatment. In women with endometriosis-associated pain, elagolix demonstrated an acceptable efficacy and safety profile in this Phase 2 study. Similar content being viewed by others

References

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Elagolix Treatment for Endometriosis-Associated Pain: Results from a Phase 2, Randomized, Double-Blind, Placebo-Controlled Study. Reprod. Sci. 21, 363–371 (2014). https://doi.org/10.1177/1933719113497292 Published: Issue date: DOI: https://doi.org/10.1177/1933719113497292

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mesh:D004715mesh:D017699endometriosis

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Endometriosis Endometriosis Hydrocarbons, Fluorinated Pelvic Pain Pelvic Pain Pyrimidines Adult Double-Blind Method Endometriosis Endometriosis Estradiol Estradiol Female Follow-Up Studies Humans Hydrocarbons, Fluorinated Pelvic Pain Pelvic Pain Pyrimidines

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