FDA Approves Orserdu for Metastatic, Estrogen Receptor-Positive Breast Cancer
On Jan. 27, 2023, the U.S. Food and Drug Administration (FDA) approved Orserdu (chemical name: elacestrant) to treat advanced-stage or metastatic, estrogen receptor-positive, HER2-negative breast cancer with an ESR1 mutation that has grown after being treated with at least one hormonal therapy medicine in men or post-menopausal women.
Advanced-stage breast cancer is either locally advanced or metastatic. Locally advanced breast cancer means the cancer has spread to tissue near the breast, but not to parts of the body away from the breast. Metastatic breast cancer means the cancer has spread to parts of the body away from the breast, such as the bones or liver.
About Orserdu
Orserdu is a type of hormonal therapy called a selective estrogen receptor downregulator or degrader (SERD). SERDs work by blocking the effects of estrogen on hormone receptor-positive breast cancer cells by sitting in the estrogen receptors on the cells. If a SERD is in the receptor, there is no room for estrogen to attach itself to the cell. If estrogen isn’t attached to the cancer cell, the cell doesn’t receive estrogen’s signals to grow and multiply.
SERDs also:
reduce the number of estrogen receptors
change the shape of estrogen receptors so they don’t work as well
Orserdu is a pill taken by mouth. You take one Orserdu pill a day, with food.
Faslodex (chemical name: fulvestrant) is another SERD approved to treat breast cancer. Faslodex is a liquid that is injected into a muscle once a month, usually at a doctor’s office. Many people would rather take a pill at home than go to a doctor’s office to get an injection. So researchers have been working to create an oral SERD.
About ESR1 mutations
The ESR1 gene makes proteins that are estrogen receptors. The receptors receive signals from estrogen that tell the cancer to grow.
Most metastatic, estrogen receptor-positive breast cancers initially respond to hormonal therapy medicines, but become resistant after a while.
Research has shown that when the ESR1 gene develops a change or mutation, it can cause the breast cancer to become resistant to hormonal therapy.
Orserdu research: The EMERALD study
FDA approval of Orserdu was based on results from the EMERALD study. The study included 477 post-menopausal women and men diagnosed with metastatic, estrogen receptor-positive, HER2-negative breast cancer that had grown while being treated with hormonal therapy and a CDK4/6 inhibitor.
Listen to The Breastcancer.org Podcast episode featuring Dr. Virginia Kaklamani discussing results from the EMERALD study.
Experimental Elacestrant Seems Effective for Breast Cancer Resistant to Other Types of Hormonal Therapy
Dec 8, 2022CDK4/6 inhibitors are a class of medicines used to treat certain types of hormone receptor-positive, HER2-negative breast cancers. These medicines target specific proteins known as cyclin-dependent kinases 4 and 6, abbreviated as CDK4/6. These kinases help control cell division. CDK4/6 inhibitors work by interfering with the kinases and stopping cancer cells from dividing and growing.
Everyone in the study had received one or two previous hormonal therapy regimens, and no one had received chemotherapy for metastatic breast cancer.
About half the people in the study were diagnosed with breast cancer that had an ESR1 mutation.
The researchers randomly assigned the people to one of two treatments:
239 people received Orserdu
238 people received the standard of care, which was the researchers’ choice of either Faslodex or an aromatase inhibitor
The results showed that people who took Orserdu had a 45% lower risk of the cancer growing or of dying from the cancer than people who received Faslodex or took an aromatase inhibitor. The results also showed that Orserdu was effective in treating breast cancer with an ESR1 mutation.
Orserdu side effects
Like almost all cancer medicines, Orserdu can cause side effects, some of them severe.
In the EMERALD study, nausea was the most common side effect of Orserdu.
Other possible Orserdu side effects are:
fatigue
vomiting
joint pain
loss of appetite
diarrhea
back pain
What this means for you
If you’ve been diagnosed with metastatic, hormone receptor-positive, HER2-negative breast cancer with an ESR1 mutation that has grown during treatment with hormonal therapy, you may want to ask your doctor about Orserdu and whether it’s right for your unique situation.
— Last updated on February 22, 2023 at 7:13 PM