Orserdu (elacestrant) is a selective estrogen receptor degrader (SERD), also known as an antiestrogen. It's used to treat advanced or metastatic ER-positive, HER2-negative breast cancer. Orserdu (elacestrant) isn't a first-choice option for this type of cancer, but typically only prescribed when other hormone therapy stopped working. Orserdu (elacestrant) is available as a tablet that’s taken by mouth once a day. This medication can cause side effects such as nausea, and muscle and joint pain.
Advanced or metastatic breast cancer that's ER-positive, HER2-negative, with the ESR1 mutation (after previous hormone therapies have stopped working)
Many breast cancers depend on hormones, like estrogen and progesterone, to grow. These specific types of breast cancer have the estrogen receptor (ER) or progesterone receptor (PR) on their cells. They are called hormone-receptor positive (HR+) breast cancer.
Orserdu (elacestrant) is a selective estrogen receptor degraders (SERDs), which is a type of hormone therapy. It binds and destroys estrogen receptors on breast cancer cells. Without estrogen, the breast cancer cells can’t grow or spread as easily.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
Taken by mouth once a day
Targeted therapy, so it works in a more specific way than traditional chemotherapy
Don't need to take it with other anticancer medications
Can raise cholesterol levels in the blood
Commonly causes nausea and muscle pain
Interacts with many medications, supplements, and food products (e.g. grapefruit juice)
Orserdu (elacestrant) is available as 345 mg tablets and 86 mg tablets. You might need to take more than one 86 mg tablet to make your prescribed dose. Take the entire Orserdu (elacestrant) dose at once at around the same time every day.
It’s best to take Orserdu (elacestrant) with food to avoid nausea. Make sure to swallow the tablets whole, don’t chew or crush the tablets.
If you forget to take your Orserdu (elacestrant) dose and it’s more than 6 hours after the usual time, skip that dose and take your next dose at the regular time.
Orserdu (elacestrant) can raise your cholesterol levels, which can raise your risk for heart attacks and strokes. Your provider will do blood tests and check on your lipid panel while you’re taking Orserdu (elacestrant). To keep your cholesterol level in a healthy range, it’s a good idea to maintain a balanced diet and engage in exercise regularly.
Orserdu (elacestrant) can interact with other medications, supplements, and foods. For example, the herbal supplement St. John’s Wort can lower Orserdu (elacestrant) levels in the blood, which might make the medication not work as well. On the other hand, grapefruit juice can raise Orserdu (elacestrant) levels in the blood, which could put you at higher risk for side effects with the medication. It’s a good idea to share a complete list of medications, supplements, and herbals with your provider so they can make sure they’re safe to take with Orserdu (elacestrant).
If you’re able to become pregnant, or if you’re male and have a partner who’s able to become pregnant, continue using effective birth control while taking Orserdu (elacestrant) and for at least a week after the last dose. There's a risk that Orserdu (elacestrant) can cause harm in an unborn baby.
Orserdu (elacestrant) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Orserdu (elacestrant) commonly raises triglyceride and cholesterol levels (lipids) in the blood. Before you start treatment with Orserdu (elacestrant), your provider will have you do a blood test to check on your cholesterol levels. They’ll continue checking your blood tests throughout treatment to make sure your lipid levels are in a safe range for you to continue the medication.
Let your provider know if you are pregnant or plan to become pregnant. Orserdu (elacestrant) is likely to harm unborn babies. If you’re able to become pregnant, your provider will have you do a pregnancy test before starting treatment. If you’re able to become pregnant, or you’re male and have a partner who’s able to become pregnant, continue using effective birth control while taking Orserdu (elacestrant) and for at least a week after the last dose. Since Orserdu (elacestrant) hasn’t been studied in people who are lactating, avoid breastfeeding while taking this medication and for 1 week after stopping.
The typical dose is 345 mg by mouth with food once a day.
Advanced or metastatic breast cancer that's ER-positive, HER2-negative, with the ESR1 mutation (after previous hormone therapies have stopped working)
Hormone receptor (HR)-positive, advanced or metastatic breast cancer
Early stage HR+ breast cancer in postmenopausal women
Advanced or metastatic HR+ breast cancer in postmenopausal women
Advanced breast cancer in postmenopausal women that's getting worse after treatment with tamoxifen
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Burstein, H. J., et al. (2023). Testing for ESR1 mutations to guide therapy for hormone receptor–positive, human epidermal growth factor receptor 2–negative metastatic breast cancer: ASCO guideline rapid recommendation update. Journal of Clinical Oncology.
Stemline Therapeutics, Inc. (2023). Orserdu- elacestrant tablet, film coated [package insert]. DailyMed.
Stemline Therapeutics, Inc. (2023). Take Orserdu once a day, every day, from anywhere.
Stemline Therapeutics, Inc. (2023). Understanding ESR1 mutations.
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