Elagolix Improves Low Hemoglobin in Women With Uterine Fibroid-Associated Heavy Menstrual Bleeding: Post Hoc Analysis of Elaris UF-1 and UF-2 [ID: 1368055]

INTRODUCTION: Women with uterine fibroids (UFs) often experience heavy menstrual bleeding (HMB) and anemia. We report improvement in hemoglobin (Hgb) levels over time with elagolix (ELA) with estradiol 1 mg/norethindrone acetate 0.5 mg once-daily add-back (AB) therapy in women with UF-associated HMB. METHODS: This post hoc analysis from duplicate, IRB-approved, randomized, double-blind, placebo (PBO)-controlled, 6-month, phase 3 Elaris UF-1 and UF-2 studies (NCT02654054 and NCT02691494) evaluated ELA 300 mg twice daily plus AB versus PBO in women with UF-associated HMB. Hgb concentration (in grams/deciliter) was assessed monthly; no adjustment for multiple comparisons were made. All patients received ELA+AB in the pivotal and extension periods. Patients with baseline Hgb>10.5 g/dL but ≤12 g/dL were classified as “HgbLow” and Hgb≤10.5 g/dL as “Hgb≤10.5.” RESULTS: Baseline demographics were balanced between treatment groups. Overall, by month 1 of treatment, patients receiving ELA+AB (n=395) showed significant improvement in mean change in Hgb compared with PBO (n=196, P=.001). At month 6, 58.8% (HgbLow) and 35.7% (Hgb≤10.5) of patients reached Hgb>12 g/dL with ELA+AB versus 27.7% and 7.2% with PBO, respectively. Improvements in Hgb levels were sustained through 12 months (HgbLow, 59.6%; Hgb≤10.5, 46.3%). During the extension period, 49.3% of patients in the Hgb≤10.5 group treated with ELA+AB reached Hgb>12 g/dL at 9 months of treatment, with responses sustained through 12 months (ELA+AB/ELA+AB, 46.3%). 71.9% of patients in the HgbLow group reached Hgb>12 g/dL by 9 months, with responses sustained through 12 months (ELA+AB/ELA+AB, 59.6%). CONCLUSION: ELA+AB results in rapid, sustained improvement in Hgb levels in women with UF-HMB, regardless of starting Hgb levels.