Efficacy and safety of elagolix with add-back therapy in women with uterine fibroids and coexisting adenomyosis.

Abstract

OBJECTIVE:

To determine if coexisting adenomyosis limits the efficacy of elagolix, an oral gonadotropin-releasing hormone antagonist, with hormonal add-back therapy in reducing heavy menstrual bleeding in women with uterine fibroids.

DESIGN:

Pooled analysis of two identical, double-blind, randomized, placebo-controlled, 6-month phase 3 trials (Elaris Uterine Fibroids [UF]-1 and UF-2).

SETTING:

A total of 153 gynecological clinical care settings in the United States and Canada.

PATIENTS:

Premenopausal women (18-51 years) with >80 mL of menstrual blood loss (MBL)/cycle and uterine fibroids with and without coexisting adenomyosis diagnosed by ultrasound and/or magnetic resonance imaging at baseline.

INTERVENTIONS:

Participants were randomized 1:1:2 to placebo, elagolix 300 mg twice daily alone, or elagolix 300 mg twice daily with estradiol 1 mg/norethindrone acetate 0.5 mg once daily.

MAIN OUTCOME MEASURES:

The primary endpoint was the proportion of women who had <80 mL of MBL during the final month and ≥50% reduction in MBL from baseline to the final month. Adverse events were monitored.

RESULTS:

Of 786 women treated across the two trials, 16% (126 women) had coexisting adenomyosis. Among this subset, a significantly greater proportion of women who received elagolix with add-back therapy (77.1% [95% confidence interval, 66.2, 88.0]) met both primary endpoint criteria compared with women who received placebo (12.2% [95% confidence interval, 1.0, 23.4]). Adverse events most frequently reported in the elagolix with add-back adenomyosis subset were hot flushes (18.3%), nausea (11.7%), and night sweats (8.3%).

CONCLUSIONS:

Elagolix with add-back therapy significantly reduced heavy menstrual bleeding in women with uterine fibroids and coexisting adenomyosis, suggesting that elagolix efficacy was not adversely affected by the presence of adenomyosis (Elaris UF-1 and UF-2 Clinical-Trials.gov numbers, NCT02654054 and NCT02691494).

• Authors: Ozgul Muneyyirci-Delale, David F Archer, Charlotte D Owens, Kurt T Barnhart, Linda D Bradley, Eve Feinberg, Veronica Gillispie, Sandra Hurtado, Jin Hee Kim, Alice Wang, Hui Wang, Elizabeth A Stewart
• Journal: F&S reports (F S Rep) Vol. 2 Issue 3 Pg. 338-346 (Sep 2021) ISSN: 2666-3341 [Electronic] United States
• PMID: 34553161 (Publication Type: Journal Article)
• Copyright: © 2021 The Author(s).