Core Insights - Eli Lilly and Company announced the FDA approval of Inluriyo (imlunestrant), an oral estrogen receptor antagonist, for treating adults with ER+, HER2–, ESR1-mutated advanced or metastatic breast cancer (MBC) whose disease progressed after at least one line of endocrine therapy [1][4][10] Group 1: Drug Efficacy and Clinical Trial Results - In the Phase 3 EMBER-3 trial, Inluriyo monotherapy reduced the risk of progression or death by 38% compared to endocrine therapy [1][4] - Among patients with ESR1-mutated MBC, Inluriyo significantly improved progression-free survival (PFS) with a median PFS of 5.5 months versus 3.8 months for fulvestrant or exemestane (HR=0.62, p-value=0.0008) [1][4] - The EMBER-3 trial enrolled 256 patients, with a majority receiving Inluriyo as first-line treatment after recurrence on adjuvant aromatase inhibitor therapy [4][9] Group 2: Treatment Mechanism and Administration - Inluriyo works by binding, blocking, and facilitating the degradation of overactive estrogen receptors, which can drive cancer growth [2][10] - It is administered as a once-daily oral treatment, providing a convenient option for patients [2][10] Group 3: Safety and Adverse Reactions - The majority of adverse events (AEs) associated with Inluriyo were low grade (Grade 1-2), with common reactions including decreased hemoglobin (30%), musculoskeletal pain (30%), and fatigue (23%) [5][13] - Serious adverse reactions occurred in 10% of patients, with fatal reactions reported in 1.8% of patients [12][13] Group 4: Market Impact and Future Studies - The approval of Inluriyo expands treatment options for patients with ESR1-mutated MBC, offering renewed hope and flexibility in disease management [6][5] - Inluriyo is also being studied in the ongoing Phase 3 EMBER-4 trial for early breast cancer at increased risk of recurrence, enrolling approximately 8,000 patients worldwide [6][10]