Elagolix with Add-Back Therapy in Women with Heavy Menstrual Bleeding, Uterine Fibroids, and Anemia: Subgroup Analysis of Two Phase 3 Trials

Abstract

Study Objective Heavy menstrual bleeding (HMB) associated with uterine fibroids (UF) often leads to anemia, which may cause fatigue and weakness in affected women. This analysis evaluated clinical improvements in menstrual blood loss (MBL), anemia, and quality of life (QoL) in elagolix-treated women who had HMB, UF, and severe or mild anemia at the time of Elaris UF-1 or UF-2 study entry. Design Pooled subgroup analysis of UF-1 and UF-2, two replicate double-blind, randomized, placebo-controlled, 6-month phase 3 studies. Setting Outpatient. Patients or Participants Subgroup of premenopausal women with HMB (>80mL alkaline hematin-measured MBL/cycle), ultrasound-confirmed UF, and severe (hemoglobin [Hgb] Interventions Elagolix 300mg BID with add-back therapy (estradiol 1mg/norethindrone acetate 0.5mg QD) (elagolix+E2/NETA), compared with placebo. Measurements and Main Results In UF-1 and UF-2, a total of 426/591 (72%) women who received elagolix+E2/NETA or placebo had severe (n=189) or mild anemia (n=237) at study entry. Women with severe anemia had a numerically greater mean baseline MBL (301.6±204.1mL) than women with mild anemia (225.8±128.2mL). Of the elagolix+E2/NETA-treated women with severe anemia at study entry, 74.1% met the study's primary endpoint (had both 2g/dL from baseline to month 6, and 51.1% achieved Hgb≥12g/dL at month 6 (P Conclusion Women with HMB, UF, and severe or mild anemia at study entry demonstrated clinical improvements in MBL, anemia, and QoL with elagolix+E2/NETA treatment.