FDA Approves Eli Lilly’s Inluriyo For Advanced Breast Cancer, Here's All You Need To Know About New Oral SERD

The U.S. Food and Drug Administration has approved a new treatment for advanced breast cancer, Fox News reports. On September 25, drugmaker Eli Lilly announced that Inluriyo, an oral estrogen receptor antagonist, has received approval to treat adults with certain forms of the disease. These include estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2–), and ESR1-mutated advanced or metastatic breast cancer.

What Is Inluriyo?

According to WebMD, Inluriyo (imlunestrant) is a new oral medication for certain cases of locally advanced or metastatic breast cancer that have progressed after at least one round of hormone therapy.

According to the same report, around half of patients with ER+, HER2- advanced or metastatic breast cancer develop ESR1 mutations after using aromatase inhibitors, a common hormonal treatment. These mutations make tumour cells more sensitive to hormones like estrogen, which fuels their growth, spread, and reduces the effectiveness of hormone therapy over time.

The once-daily pill is intended for patients whose disease has progressed after at least one course of endocrine (hormone) therapy, according to a press release.

As per the report, in the phase 3 EMBER-3 trial, Inluriyo lowered the risk of cancer progression or death by 38% compared with endocrine therapy.

Patients with ESR1-mutated metastatic breast cancer experienced a "significant" improvement in progression-free survival with Inluriyo, compared to other hormone treatments such as fulvestrant or exemestane, with a median survival of 5½ months versus 3.8 months.

What is the function and side effects of this pill?

According to Fox News, Eli Lilly noted in the press release that “some cancers develop mutations that can cause estrogen receptors to 'become overactive and drive cancer growth.'” Inluriyo works by binding to, blocking, and helping degrade these receptors, which slows the disease’s progression.

Inluriyo carries a warning that it may harm an unborn baby. Women who are pregnant or might become pregnant should consult their doctor before using it. In the phase 3 trial, most side effects were “low grade” but included lab abnormalities, musculoskeletal pain, fatigue, diarrhea, nausea, constipation, abdominal pain, higher cholesterol and triglycerides, and lower levels of haemoglobin, calcium, platelets, white blood cells, and certain liver enzymes, according to the FDA.

WebMD reports that Eli Lilly said Inluriyo will continue to be studied in the ongoing phase 3 EMBER-4 trial, which focuses on patients with ER+, HER2– early breast cancer at higher risk of recurrence. This trial plans to enrol around 8,000 patients worldwide.

The medicine is expected to become available in the U.S. within a few weeks of approval.

Also Read: What is 'Planetary Health Diet' and How Adopting Plant-Based Diets Saves 15 Million Lives Annually