The U.S. FDA has approved Eli Lilly's oral estrogen receptor antagonist, Inluriyo (imlunestrant), to treat advanced breast cancer.
Inluriyo once-daily 200 mg tablets bind to, block, and facilitate the degradation of overactive estrogen receptors in breast cancer that has developed ESR1 mutations. The treatment is approved for estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2–), ESR1-mutated advanced, metastatic breast cancer (MBC). Inluriyo is for adults whose disease has progressed after at least one line of endocrine therapy (ET).
THe FDA approval is based on positive results in the phase 3 EMBER-3 trial in patients with ESR1-mutated MBC. Inluriyo reduced the risk of progression or death by 38% compared to ET. There was also a significant improvement in progression-free survival, with a median of 5.5 months with Inluriyo compared to a median of 3.8 months with fulvestrant or exemestane.
The phase 3 EMBER-4 trial is now assessing Inluriyo for patients with ER+, HER2– early breast cancer at increased risk of recurrence.