Eli Lilly’s Oral SERD Inluriyo Approved by FDA for ESR1-Mutated Breast Cancer
The FDA approved Eli Lilly's oral SERD Inluriyo (imlunestrant) for adults with ER-positive, HER2-negative, ESR1-mutated advanced or metastatic breast cancer, whose disease progressed after at least one prior endocrine therapy.135
Inluriyo targets the ESR1 gene mutation, which contributes to therapy resistance and occurs in roughly half of these breast cancer cases after exposure to hormone treatments.1
Clinical data from the EMBER-3 study showed Inluriyo reduced the risk of disease progression or death by 38% compared to standard endocrine therapies, with a median progression-free survival of 5.5 months—about 2 months longer than standard therapy.18
Most side effects were low grade (including lower hemoglobin and white cell counts, fatigue, diarrhea) with 4.6% discontinuations and 10% interrupted treatments due to adverse events; the prescribing info includes a warning for fetal toxicity.1
The Guardant360 CDx was approved as a companion diagnostic to identify suitable patients with ESR1 mutations for treatment with Inluriyo.3
A 28-day supply of Inluriyo has a list price of $22,500 per patient.1
Inluriyo joins Menarini’s Orserdu as approved oral SERDs, marking a shift away from injectable fulvestrant, and other oral SERDs from Roche, AstraZeneca, Arvinas/Pfizer are in late-stage review.1
Lilly is studying Inluriyo for potential 'adjuvant' use in early breast cancer to prevent relapse, with data expected in 2027.1
Expert commentary highlights Inluriyo as an important new option for patients with ESR1 mutations, though its overall impact on cancer care and its effectiveness in non-ESR1-mutant populations remain uncertain.1
Sources:
1. https://www.biopharmadive.com/news/eli-lilly-fda-approve-inluriyo-breast-cancer-oral-serd/761188/
3. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-imlunestrant-er-positive-her2-negative-esr1-mutated-advanced-or-metastatic-breast
5. https://www.ajmc.com/view/fda-approves-imlunestrant-for-er-and-her2-negative-breast-cancer
8. https://www.biospace.com/fda/lillys-oral-serd-wins-fda-go-ahead-for-breast-cancer