Abstract P1-17-10: H3B-6545, a novel selective estrogen receptor covalent antagonist (SERCA), in estrogen receptor positive (ER+), human epidermal growth factor receptor 2 negative (HER2-) advanced breast cancer - A phase II study

作者：Erika Hamilton, Judy S. Wang, Timothy Pluard, Aki Morikawa, E. Claire Dees, Robert H. Jones, Barbara Haley, Anne Armstrong, Adam L. Cohen, Pamela N. Münster, Gail S. Wright, Fadi Kayali, Lisa Cantagallo, Manav Korpal, Jenny Long, Jianjun Xiao, Benoit Destenaves, Lei Gao, Tarek Sahmoud, Antonio Gualberto, Dejan Juric · 发表于：Cancer Research · 年份：2022 · DOI：10.1158/1538-7445.sabcs21-p1-17-10 · 被引用次数：9 · 研究领域：Advanced Breast Cancer Therapies、Click Chemistry and Applications、Estrogen and related hormone effects

Abstract Purpose: H3B-6545, a novel Selective ERα Covalent Antagonist (SERCA), inactivates both and wild-type and mutant ERα by targeting cysteine 530 and enforcing antagonist conformation. H3B-6545 demonstrated preclinical high activity in breast cancer models with constitutively active ESR1 mutations (Furman C, SABCS 2020) and clinical activity in pretreated women with ER+ breast cancer (Hamilton EP, ASCO 2021). Patients and Methods: The primary objective of the phase II is to estimate the objective response rate (ORR), clinical benefit rate (CBR), progression-free survival (PFS), and secondary objectives include safety. Results: 94 pts were treated with 450 mg daily, the recommended phase II dose: 11 in the phase I and 83 in the phase II parts of the trial. Patients and tumor characteristics were presented previously (Hamilton EP, ASCO, 2021). As of March 31, 2021, grade (gr) 2 or higher adverse events (AE) reported in ≥10% were anemia (19%), nausea (17%), fatigue (16%), and diarrhea (12%). Laboratory gr 2 or higher abnormalities reported in ≥10% pts were creatinine clearance decrease (39%), hemoglobin decrease (38%), Lymphocytes decrease (37%), ALT increase (14%), AST increase (13%), bilirubin increase (12%), and creatinine increase (12%). AE of gr 1 sinus bradycardia (asymptomatic) was reported in 35% and gr 2 (symptomatic, no intervention needed) was reported in 5%. Gr 2 and 3 QTcF prolongation were reported in 2 and 3 pts, respectively. There were no treatment-related ...