Inluriyo (imlunestrant) for ER-positive, HER2-negative, ESR1-mutated advanced or metastatic breast cancer

Initial US Approval:

2025

Key Clinical Studies:

EMBER-3 (NCT04975308)

Drug Class/Description:

Estrogen receptor antagonist

Indications and Usage:

INLURIYOTM is an estrogen receptor antagonist indicated for:

• treatment of adults with ER-positive, HER2-negative, ESR1-mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy 

Dosage and Administration:

• Select patients for treatment based on the presence of ESR1 mutations. 
• The recommended dosage is 400 mg orally once daily, on an empty stomach.
• Reduce the dose in patients with moderate or severe hepatic impairment
• Dosage modifications may be required.

Dosage Forms and Strengths:

Tablets: 200 mg of imlunestrant.

Contraindications:

None.

Warnings and Precautions:

• Embryo-Fetal Toxicity: INLURIYO can cause fetal harm. Advise of the potential risk to a fetus and to use effective contraception.

Adverse Reactions:

The most common (incidence ≥10%) adverse reactions, 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. 

Drug Interactions:

• Strong CYP3A Inhibitors: Avoid concomitant use with INLURIYO. If concomitant use cannot be avoided, decrease the INLURIYO dosage.
• Strong CYP3A Inducers: Avoid concomitant use with INLURIYO. If concomitant use cannot be avoided, increase the INLURIYO dosage.

Use in Specific Populations:

• Lactation: Advise not to breastfeed.

Adapted From:

https://pi.lilly.com/us/inluriyo-uspi.pdf?s=pi&redirect-referrer=https%3A%2F%2Finvestor.lilly.com%2Fnews-releases%2Fnews-release-details%2Fus-fda-approves-inluriyo-imlunestrant-adults-er-her2-esr1

 

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