- Imlunestrant as monotherapy shows a 38% risk reduction in progression or death in ESR1-mutated disease.
- The combination of imlunestrant and abemaciclib achieves a median PFS of 10.9 months.
- Median time to chemotherapy is extended by over a year with the combination therapy.
- Phase 3 EMBER-4 trial enrolled about 8,000 patients for ER+, HER2- early breast cancer.
Study Overview
Eli Lilly's Phase 3 EMBER-3 study evaluates Inluriyo (imlunestrant), an oral estrogen receptor antagonist, in ER+, HER2- advanced breast cancer. The study focuses on patients whose disease progressed after aromatase inhibitor treatment, with or without a CDK4/6 inhibitor.
Monotherapy Results
Imlunestrant as monotherapy shows a 38% reduction in the risk of progression or death in patients with ESR1-mutated disease. The median progression-free survival (PFS) is 5.5 months compared to 3.8 months with endocrine therapy, and median overall survival (OS) improves by 11.4 months.
Combination Therapy
The combination of imlunestrant and abemaciclib reduces the risk of progression or death by 41% compared to imlunestrant alone. It achieves a median PFS of 10.9 months and extends the median time to chemotherapy by over a year. In patients with ESR1-mutated disease, median PFS extends to 11.0 months versus 5.6 months with imlunestrant alone.
Future Research
Imlunestrant is also being investigated in the adjuvant setting for ER+, HER2- early breast cancer with a high risk of recurrence. The Phase 3 EMBER-4 trial has completed enrollment of approximately 8,000 patients following two to five years of adjuvant endocrine therapy.
