Retevmo
Retevmo (selpercatinib) is a targeted therapy for advanced or metastatic cancers with changes (mutations) in the RET gene. In particular, it’s a recommended option for non-small cell lung cancer (NSCLC) and thyroid cancer that have RET mutations. Retevmo (selpercatinib) is available as pills that are taken by mouth twice a day. But it often causes troublesome fatigue, swelling, and diarrhea as side effects.
What is Retevmo (selpercatinib)?
What is Retevmo (selpercatinib) used for?
Advanced or metastatic NSCLC with RET gene fusion in adults
Advanced or metastatic thyroid cancers with RET mutations in adults and children age 12 years and older
Advanced or metastatic tumors with RET mutations in adults, when other treatments haven’t worked or aren’t available
How Retevmo (selpercatinib) works
RET is a protein in the body that signals cells to grow and divide. Your body makes RET proteins using instructions given by the RET gene.
In certain cancers, changes (mutations) in the RET gene lead to abnormal RET proteins. These abnormal proteins cause cancer cells to grow out of control.
Retevmo (selpercatinib) is a type of kinase inhibitor called a RET inhibitor. It blocks the RET protein, so the cancer can’t grow and spread as easily.
Drug Facts
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What are the side effects of Retevmo (selpercatinib)?
Common Side Effects
- Signs of stress to the liver or kidney on blood tests (up to 59%)
- Abnormal electrolyte levels in the blood (up to 59%)
- Lower blood cell counts (up to 52%)
- Swelling (49%)
- Diarrhea (47%)
- Feeling very tired (46%)
- Dry mouth (43%)
- High blood pressure (41%)
- Stomach pain (34%)
- Constipation (33%)
- Rash (33%)
- Nausea (31%)
- Headache (28%)
Other Side Effects
- Cough
- Having trouble catching your breath
- Joint pain
- Bleeding
- Abnormal heart rhythm
Serious Side Effects
- Liver injury: pain in the right side of the stomach, yellowing of the eyes or skin, dark or brown urine
- Lung damage: cough, shortness of breath, fever
- High blood pressure: headache, dizziness, confusion, chest pain
- Abnormal heart rhythm: chest pain, shortness of breath, dizziness, fluttering or pounding heart beat
- Severe bleeding: sudden or painful headache, changes in vision, severe stomach pain, coughing or spitting up blood
- Tumor lysis syndrome: muscle cramps, dark or brown urine, fluttering or pounding heart beat
- Allergic reaction: fever, rash, muscle, bone, or joint pain
Source: DailyMed
The following side effects have also been reported
Side effects that you should report to your care team as soon as possible:
- Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
- Bleeding—bloody or black, tar-like stools, vomiting blood or brown material that looks like coffee grounds, red or dark brown urine, small red or purple spots on skin, unusual bruising or bleeding
- Dry cough, shortness of breath or trouble breathing
- Heart rhythm changes—fast or irregular heartbeat, dizziness, feeling faint or lightheaded, chest pain, trouble breathing
- Increase in blood pressure
- Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue
- Low thyroid levels (hypothyroidism)—unusual weakness or fatigue, increased sensitivity to cold, constipation, hair loss, dry skin, weight gain, feelings of depression
- Tumor lysis syndrome (TLS)—nausea, vomiting, diarrhea, decrease in the amount of urine, dark urine, unusual weakness or fatigue, confusion, muscle pain or cramps, fast or irregular heartbeat, joint pain
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
- Constipation
- Diarrhea
- Dry mouth
- Nausea
- Rash
- Swelling of the ankles, hands, or feet
Pros and cons of Retevmo (selpercatinib)
Pros
A pill that’s swallowed and taken with or without food
Recommended treatment option for NSCLC and thyroid cancer with RET mutation
Targeted therapy option for people with cancers with a RET mutation
Cons
Interacts with many common medications, including heartburn medications and certain antibiotics (e.g., fluconazole (Diflucan))
Commonly causes swelling, fatigue, and diarrhea
Has risks of severe bleeding and abnormal heart rhythms
Pharmacist tips for Retevmo (selpercatinib)
You’ll need to take a few capsules of Retevmo (selpercatinib) for each of your doses. This medication comes as 40 mg and 80 mg capsules. For a typical 160 mg dose, you can use four 40 mg capsules or two 80 mg capsules. Remember to take each dose twice a day.
Swallow the Retevmo (selpercatinib) capsules whole; don’t chew or crush the medication.
If you miss a dose of Retevmo (selpercatinib), take it as soon as you remember. If it’s within 6 hours of your next dose time, skip the missed dose and continue taking Retevmo (selpercatinib) at the usual time.
If you vomit after taking Retevmo (selpercatinib), don’t take an extra dose to make up for it. Wait until the next time you typically take the medication for your usual dose.
Try to avoid taking heartburn medications while you’re using Retevmo (selpercatinib) because the cancer medication doesn’t work as well if you take them together. Talk to your provider if you’re having troublesome heartburn for tips on relieving indigestion aside from medications. But if you do need acid-reducing medications, you’ll have to adjust how you take your medications so they work well.
If you need to take a proton pump inhibitor like omeprazole (Prilosec) for heartburn, take Retevmo (selpercatinib) with food.
If you need to take an H2 blocker like famotidine (Pepcid AC) for indigestion, take Retevmo (selpercatinib) 2 hours before or 10 hours after taking the heartburn medication.
If you take antacids like Tums for heartburn, make sure to separate Retevmo (selpercatinib) from them by at least 2 hours.
If you’re starting any new medications or supplements, talk with your provider or pharmacist first to make sure they’re safe to take with Retevmo (selpercatinib). Retevmo (selpercatinib) can interact with other medications. These interactions could cause your cancer medication to not work as well or put you at higher risk for side effects. For example, taking the antifungal medication fluconazole (Diflucan) with Retevmo (selpercatinib) might raise your risk of side effects from the cancer medication (like swelling, diarrhea, or liver injury).
If you’re able to become pregnant or have a partner who’s able to become pregnant, use effective birth control during treatment and for 1 week after the last dose. If you’re breastfeeding a baby, avoid breastfeeding during treatment and for 1 week after stopping the medication. This is because it’s possible for Retevmo (selpercatinib) to harm the unborn baby or breastfeeding infant.
If your child is starting treatment with Retevmo (selpercatinib), their provider will track their growth by periodically checking scans and taking measurements. Animal studies show that it’s possible that the medication can cause changes in bone growth in children. So provider visits are important to make sure the medication isn’t affecting your child’s growth pattern.
Frequently asked questions about Retevmo (selpercatinib)
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What are the risks and warnings for Retevmo (selpercatinib)?
Retevmo (selpercatinib) 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.
Liver injury
Retevmo (selpercatinib) can potentially harm your liver. In studies, people taking the medication had higher liver enzyme levels in the blood, which can suggest liver injury. Sometimes, this happened within the first 6 weeks of starting the medication.
Because you might not feel any symptoms when your liver is having problems, you’ll need to get blood tests done to track how well your liver is working. You’ll typically need these blood tests before you start Retevmo (selpercatinib), every 2 weeks for the first few months of treatment, and then every month after that. Tell your provider if you notice any symptoms of liver damage, such as pain on the right side of the stomach, yellowing of the eyes or skin, or dark urine.
You might need to take a break from Retevmo (selpercatinib) if your provider thinks that you have liver damage. Once your liver test results return to normal, you might be able to restart treatment at a lower dose.
Lung damage
Although rare, Retevmo (selpercatinib) can cause damage to the lungs, which can sometimes be life-threatening. Let your healthcare team know if you experience new or worsened cough, shortness of breath, or fevers. You’ll probably need to stop the medication while your provider checks your lungs for problems.
High blood pressure
Retevmo (selpercatinib) can raise your blood pressure. High blood pressure typically doesn’t cause noticeable symptoms, but you might feel dizzy, have changes in vision, or have headaches if it gets unusually high.
Before you start Retevmo (selpercatinib), your provider will check your blood pressure to make sure Retevmo (selpercatinib) is safe to use. Check your blood pressure at home 1 week after starting the medication and then at least once a month while you’re receiving treatment.
Let your provider know if your blood pressure is higher than usual or if you have symptoms of very high blood pressure. You might need to start taking blood pressure medications. If that’s not enough, you might need to take a break from Retevmo (selpercatinib) and then possibly restart treatment at a lower dose once your blood pressure gets to a safe range. Your provider might switch you to a different cancer medication if your blood pressure stays dangerously high, even with blood pressure medications to help.
Abnormal heart rhythm
Risk factors: High blood levels of Retevmo (selpercatinib) | Personal or family history of abnormal heart rhythms (arrhythmias) | Severe heart failure | Low potassium or magnesium in the blood | Taking other medications that cause QT prolongation
Retevmo (selpercatinib) can cause changes to your heart’s electrical activity called QT prolongation. This can affect your heart rhythm and can sometimes be serious or life-threatening. Your risk depends on your genetics, your electrolyte levels, and whether you’re taking other medications that can also cause QT prolongation. Your provider will order an electrocardiogram (EKG) to check your heart’s electrical activity and blood tests to measure your electrolyte levels. These tests are typically done before starting Retevmo (selpercatinib) and regularly during treatment to make sure it’s safe for you to take.
Share your medication list, including supplements and herbal products, with your provider so they can check your risk for abnormal heart rhythm. Tell your healthcare team right away if you notice new pounding or fluttering heartbeat, lightheadedness, dizziness, or chest pain. They can check your heart, and they might have you take a break from Retevmo (selpercatinib). Once your heart rhythm returns to normal, you might be able to restart the medication at a lower dose.
Serious bleeding
Retevmo (selpercatinib) can raise the risk of serious bleeding, which can be fatal in rare cases. Bleeding can happen anywhere in the body; there were rare cases of bleeding in the lungs, stomach, and brain during clinical studies.
Let your healthcare provider know right away if you experience any serious or unusual bleeding, especially bleeding that’s difficult to stop. Get medical help as soon as possible if you feel nauseous, have a sudden or painful headache, notice a change in your vision, have stomach pain, or are coughing or spitting up blood.
Surgery and wound healing problems
Retevmo (selpercatinib) might make it harder for wounds to heal. Tell your provider if you have an injury and notice your wounds are healing slowly. Also let your provider know if you’re planning to have surgery or other procedures. Your provider will need to give you instructions on when to stop and restart Retevmo (selpercatinib). In general, you should stop taking Retevmo (selpercatinib) at least 7 days before a planned surgery. After a major surgery, you should stay off Retevmo (selpercatinib) for at least 2 weeks and check with your healthcare team to make sure your wound has healed before restarting treatment.
Allergic reactions
Some people had allergic reactions to Retevmo (selpercatinib). In studies, reactions happened anywhere between 5 days and 2 years of taking the medication. Let your provider know if you develop fevers, rash, or muscle, bone, or joint pain after starting Retevmo (selpercatinib). Those might be signs of an allergic reaction.
Your provider will examine your symptoms and do other tests to check whether you’re having an allergic reaction to Retevmo (selpercatinib). If you are, you’ll have to stop the medication and possibly start corticosteroids to lower inflammation from the allergic reaction. Depending on how severe the reaction is, you might restart Retevmo (selpercatinib) at a lower dose or form a different treatment plan once your allergic reaction goes away.
Tumor lysis syndrome
Risk factors: Kidney problems | Dehydration | Thyroid cancer | High tumor burden
Although rare, treatment with Retevmo (selpercatinib) can cause a serious reaction called tumor lysis syndrome (TLS). TLS happens when many cancer cells die quickly and suddenly break down in your body. In the process, these cells release their inner contents (like uric acid, potassium, and phosphorus) into your blood. High levels of uric acid and electrolytes in your body can cause serious problems, such as kidney damage and abnormal heart rhythms.
Your provider will order labs for you regularly to check for signs of TLS. They’ll also recommend that you drink enough fluids daily to keep hydrated. If needed, they might also give you intravenous (IV) fluids and prescribe you medications to lower your uric acid levels. Tell your provider right away if you’re urinating less than usual or have dark urine, muscle cramps, or a racing heartbeat. These can be symptoms of kidney damage or heart rhythm problems that might be related to TLS.
Low thyroid hormone levels
Retevmo (selpercatinib) can cause your thyroid hormone levels to drop too low (hypothyroidism). Let your provider know if you have fatigue that won’t go away or weight gain, since these could be signs of very low thyroid hormone levels. Your provider will check your thyroid hormone levels before starting this medication and then regularly during treatment to make sure your hormone levels are normal.
Harm to the unborn baby
Let your provider know if you’re pregnant or planning to become pregnant. Retevmo (selpercatinib) hasn’t been studied in human pregnancy, but it’s possible that the medication can cause harm to the unborn baby based on findings from animal studies. If you’re able to become pregnant, your provider will have you take a pregnancy test before starting treatment. They’ll also ask you to use effective birth control while taking this medication and for at least a week after your last dose. If you’re male and have a partner who’s able to become pregnant, make sure to use condoms if you have sex while taking Retevmo (selpercatinib) and until at least a week after the last dose.
Retevmo (selpercatinib) dosage forms
Typical dosing for Retevmo (selpercatinib)
The dose is based on your weight.
People weighing 110 lb or more: The typical dose is 160 mg by mouth twice a day, about 12 hours apart.
People weighing less than 110 lb: The typical dose is 120 mg by mouth twice a day, about 12 hours apart.
How much does Retevmo (selpercatinib) cost?
What are alternatives to Retevmo (selpercatinib)?
Advanced or metastatic NSCLC with RET gene fusion in adults
Advanced or metastatic thyroid cancers with RET mutations in adults and children age 12 years and older
Advanced or metastatic tumors with RET mutations in adults, when other treatments haven’t worked or aren’t available
Metastatic NSCLC with RET gene fusion in adults
Advanced or metastatic thyroid cancers with RET mutations, in adults and children 12 years of age or older
What is the latest news about Retevmo (selpercatinib)?
Retevmo (selpercatinib) images
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References
Best studies we foundAmerican Cancer Society. (2019). What is thyroid cancer?
American Cancer Society. (2020). Mouth dryness or thick saliva.
American Cancer Society. (2021). How targeted therapies are used to treat cancer.
American Cancer Society. (2022). Gene changes and cancer.
American Lung Association. (2021). RET and lung cancer.
Eli Lilly and Company (2023). Retevmo- selpercatinib capsule [package insert]. DailyMed.
Eli Lilly and Company (2023). Taking Retevmo.
Eli Lilly and Company (2023). Understanding biomarker testing.
Farzam, K., et al. (2023). QT prolonging drugs. StatPearls.
Gupta, A., et al. (2018). Tumor lysis syndrome. Journal of the American Medical Association Oncology.
MedlinePlus. (2018). RET gene.
MedlinePlus. (2022). Dry mouth during cancer treatment.
National Cancer Institute. (2021). Edema (swelling) and cancer treatment.
National Cancer Institute. (2023). Nausea and vomiting related to cancer treatment (PDQ®)–Health professional version.
National Cancer Institute. (2023). Non-small cell lung cancer treatment (PDQ®)–Patient version.
National Comprehensive Cancer Network. (2022). Thyroid cancer.
National Comprehensive Cancer Network. (2023). Metastatic non-small cell lung cancer.
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