Thursday, October 30, 2025

FDA Approves Inluriyo (imlunestrant) for Adults with ER+, HER2-, ESR1-Mutated Advanced or Metastatic Breast Cancer

Eli Lilly and Company (NYSE: LLY) announced  the U.S. Food and Drug Administration (FDA)  approval of  Inluriyo (imlunestrant, 200 mg tablets), an oral estrogen receptor antagonist, for the treatment of adults with estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2–), ESR1-mutated advanced or metastatic breast cancer (MBC) whose disease progressed after at least one line of endocrine therapy (ET). In the Phase 3 EMBER-3 trial, Inluriyo reduced the risk of progression or death by 38% versus ET. Among patients with ESR1-mutated MBC, Inluriyo significantly improved progression-free survival (PFS) versus fulvestrant or exemestane, with a median PFS of 5.5 months vs 3.8 months (HR=0.62 [95% CI: 0.46-0.82]); p-value=0.0008.





Inluriyo is a treatment for ER+, HER2–, ESR1-mutated MBC. Some breast cancers develop ESR1 mutations that can cause estrogen receptors to become overactive and drive cancer growth. Inluriyo binds, blocks, and facilitates the degradation of these receptors, helping to slow disease progression. Its once-daily dosing provides patients with an oral treatment option.

"This therapy reflects our commitment to developing treatments that improve outcomes for people with breast cancer and represents an important step toward advancing innovative, all-oral treatment approaches," said Jacob Van Naarden, executive vice president and president of Lilly Oncology. "We are deeply grateful to the patients, investigators, Lilly team members and clinical care teams who made this advancement possible. This therapy has the potential to make the treatment journey more manageable for those living with breast cancer."

The Inluriyo label contains a warning and precaution for embryo-fetal toxicity.

The FDA approval is based on the results of the EMBER-3 trial in the patient population harboring ESR1-mutated MBC (n=256). Patients received Inluriyo or ET as first-line treatment for MBC following recurrence on adjuvant aromatase inhibitor (AI), +/- prior CDK4/6 inhibitor (21%), or as second-line treatment for MBC following progression on AI, +/- prior CDK4/6 inhibitor (79%).

"This represents an important advancement for patients with ESR1-mutated MBC, a mutation found in nearly half of patients who have taken hormone therapies, often contributing to treatment resistance," said Komal Jhaveri, M.D., FACP, FASCO, section head of Endocrine Therapy Research and clinical director of Early Drug Development at Memorial Sloan Kettering Cancer Center, and a principal investigator of EMBER-3. "With its demonstrated efficacy, tolerability profile and oral administration, this therapy provides a meaningful alternative treatment option for this patient population."

In EMBER-3, the majority of adverse events (AEs) with Inluriyo were low grade (Grade 1-2) and the most common adverse reactions (≥10%), including laboratory abnormalities, were hemoglobin decreased, musculoskeletal pain, calcium decreased, neutrophils decreased, AST increased, fatigue, diarrhea, ALT increased, triglycerides increased, nausea, platelets decreased, constipation, cholesterol increased, and abdominal pain. In the study, 4.6% of patients permanently discontinued treatment due to AEs. Dose reductions and dose interruptions occurred in 2.4% and 10% of patients, respectively.

"The approval of Inluriyo expands the metastatic breast cancer treatment landscape for patients who test positive for the ESR1 mutation," said Jean Sachs, CEO, Living Beyond Breast Cancer. "Eligible patients will now have access to an additional treatment option, offering them the potential for flexibility in their daily lives and disease management, and—above all—renewed hope for the future."

Inluriyo is also being studied in the ongoing Phase 3 EMBER-4 trial in the adjuvant setting for people with ER+, HER2– early breast cancer (EBC) at increased risk of recurrence, which is enrolling approximately 8,000 patients worldwide.

https://en.wikipedia.org/wiki/Imlunestrant#:~:text=Society%20and%20culture-,Legal%20status,under%20the%20brand%20name%20Inluriyo.