1.
Elagolix for Heavy Menstrual Bleeding in Women with Uterine Fibroids.
Schlaff, WD, Ackerman, RT, Al-Hendy, A, Archer, DF, Barnhart, KT, Bradley, LD, Carr, BR, Feinberg, EC, Hurtado, SM, Kim, J, et al
The New England journal of medicine. 2020;(4):328-340
Abstract
BACKGROUND Uterine fibroids are hormone-responsive neoplasms that are associated with heavy menstrual bleeding. Elagolix, an oral gonadotropin-releasing hormone antagonist resulting in rapid, reversible suppression of ovarian sex hormones, may reduce fibroid-associated bleeding. METHODS We conducted two identical, double-blind, randomized, placebo-controlled, 6-month phase 3 trials (Elaris Uterine Fibroids 1 and 2 [UF-1 and UF-2]) to evaluate the efficacy and safety of elagolix at a dose of 300 mg twice daily with hormonal "add-back" therapy (to replace reduced levels of endogenous hormones; in this case, estradiol, 1 mg, and norethindrone acetate, 0.5 mg, once daily) in women with fibroid-associated bleeding. An elagolix-alone group was included to assess the impact of add-back therapy on the hypoestrogenic effects of elagolix. The primary end point was menstrual blood loss of less than 80 ml during the final month of treatment and at least a 50% reduction in menstrual blood loss from baseline to the final month; missing data were imputed with the use of multiple imputation. RESULTS A total of 412 women in UF-1 and 378 women in UF-2 underwent randomization, received elagolix or placebo, and were included in the analyses. Criteria for the primary end point were met in 68.5% of 206 women in UF-1 and in 76.5% of 189 women in UF-2 who received elagolix plus add-back therapy, as compared with 8.7% of 102 women and 10% of 94 women, respectively, who received placebo (P<0.001 for both trials). Among the women who received elagolix alone, the primary end point was met in 84.1% of 104 women in UF-1 and in 77% of 95 women in UF-2. Hot flushes (in both trials) and metrorrhagia (in UF-1) occurred significantly more commonly with elagolix plus add-back therapy than with placebo. Hypoestrogenic effects of elagolix, especially decreases in bone mineral density, were attenuated with add-back therapy. CONCLUSIONS Elagolix with add-back therapy was effective in reducing heavy menstrual bleeding in women with uterine fibroids. (Funded by AbbVie; Elaris UF-1 and Elaris UF-2 ClinicalTrials.gov numbers, NCT02654054 and NCT02691494.).
2.
A phase 1b study evaluating the effect of elacestrant treatment on estrogen receptor availability and estradiol binding to the estrogen receptor in metastatic breast cancer lesions using 18F-FES PET/CT imaging.
Jager, A, de Vries, EGE, der Houven van Oordt, CWM, Neven, P, Venema, CM, Glaudemans, AWJM, Wang, Y, Bagley, RG, Conlan, MG, Aftimos, P
Breast cancer research : BCR. 2020;(1):97
Abstract
BACKGROUND Elacestrant is an oral selective estrogen receptor (ER) degrader. This phase 1b open-label, non-randomized study (RAD1901-106) was initiated to determine the effect of elacestrant on the availability of ER in lesions from postmenopausal women with ER+ advanced breast cancer (ABC) using 16α-18F-fluoro-17β-estradiol positron emission tomography with low-dose computed tomography (FES-PET/CT). METHODS Eligible patients were postmenopausal women with ER+, HER2- ABC; tumor progression after ≥ 6 months of 1-3 lines of endocrine treatment for ABC; and measurable or evaluable disease. Two 8-patient cohorts were enrolled: one treated with 400 mg elacestrant once daily (QD) and one treated with 200 mg elacestrant QD with dose escalation to 400 mg QD after 14 days. Elacestrant was dosed continuously until progressive disease, toxicity, or withdrawal. FES-PET/CT was performed pre-dose at baseline and 4 h post-dose on day 14. The primary endpoint was the percentage difference in FES uptake in tumor lesions (maximum 20) after 14 days of treatment compared to baseline. Overall response was investigator-assessed by Response Evaluation Criteria in Solid Tumors [RECIST] version 1.1. RESULTS Patients (n = 16; median age, 53.5 years) had ABC with a median 2.5 prior lines of endocrine therapy. Median reduction in tumor FES uptake from baseline to day 14 was 89.1% (Q1, Q3: 75.1%, 94.1%) and was similar in both cohorts (89.1% [Q1, Q3: 67.4%, 94.2%], 200/400 mg and 88.7% [Q1, Q3: 79.5%, 94.1%], 400 mg). Residual ER availability (> 25% persistence in FES uptake) on day 14 was observed in 3 patients receiving 200/400 mg (3/78, 37.5%) and 1 patient receiving 400 mg (1/8, 12.5%). The overall response rate (ORR) was 11.1% (1 partial response), and clinical benefit rate (CBR) was 30.8%. Median percentage change in FES uptake did not correlate with ORR or CBR. Adverse events occurring in > 20% of the patients were nausea (68.8%), fatigue (50.0%), dyspepsia (43.8%), vomiting (37.5%), and decreased appetite, dysphagia, and hot flush (31.3% each). Most events were grade 2 in severity. CONCLUSION Elacestrant 200 mg and 400 mg QD greatly reduced ER availability measured by FES-PET/CT. In a heavily pretreated population, elacestrant was associated with antitumor activity. TRIAL REGISTRATION ClinicalTrials.gov, NCT02650817 . Registered on 08 January 2016.