Ayvakit (avapritinib) is a medication that’s FDA approved in adults to treat a certain type of cancer of the digestive system called gastrointestinal stromal tumor (GIST). It also treats adults with systemic mastocytosis, a blood cancer related to immune cells called mast cells. Ayvakit (avapritinib) is a type of targeted therapy called a tyrosine kinase inhibitor. It’s a tablet that’s taken by mouth once a day on an empty stomach. Common side effects include swelling, tiredness, and nausea. It can also cause changes in memory and attention.
Gastrointestinal stromal tumor (GIST) with PDGFRA mutations (can’t be treated with surgery or has spread to other parts of the body)
Indolent (mild) or advanced form of systemic mastocytosis
Ayvakit (avapritinib) is a tyrosine kinase inhibitor.
In the body, tyrosine kinases are proteins that help make sure cells grow and work normally. But in people with GIST or systemic mastocytosis, certain tyrosine kinases like PDGFRA and KIT can become overly active and cause cells to grow out of control.
Ayvakit (avapritinib) blocks the PDGFRA and KIT proteins. This helps slow down the condition’s growth.
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):
A tablet that’s taken by mouth just once a day
Recommended option for people with GIST with specific mutations or people with certain types of systemic mastocytosis
Must take on an empty stomach
Can cause problems with attention, thinking, and memory
Take Ayvakit (avapritinib) once a day on an empty stomach, at least 1 hour before or 2 hours after a meal.
Ayvakit (avapritinib) is available as 25 mg, 50 mg, 100 mg, 200 mg, and 300 mg tablets. You might need to take more than one tablet each time to make up your regular dose. Ask your oncologist or pharmacist if you have questions about your dose and how to take it.
If you miss a dose of Ayvakit (avapritinib) and it’s within 8 hours of your next dose, skip the dose you missed and take your next dose as usual. If you vomit after you take Ayvakit (avapritinib), there’s no need to take an extra dose to make up for it. Don’t double your dose because it can raise your risk for side effects.
Changes in memory, attention, or confusion are common side effects of Ayvakit (avapritinib). They’re usually mild and don’t typically affect people’s daily routines. If you notice these changes, avoid driving, operating heavy machinery, or doing anything that you need your complete attention for until you can check in with your oncology team. Also speak with them if these side effects get too troublesome.
Ayvakit (avapritinib) can make your skin more sensitive to the sun and make it easier for you to get sunburns, even a week after stopping the medication. To protect your skin, try to limit your time in the sun and exposure to other forms of ultraviolet (UV) light, like tanning beds. When you go outside, it’s a good idea to keep your skin covered and wear sunscreen.
Share your complete medication list, which should include over-the-counter products and supplements, with your oncology team. They can review your medications to check that they’re all safe for you to take. Ayvakit (avapritinib) can interact with other medications and supplements. These drug interactions can either make Ayvakit (avapritinib) work less well or raise your risk for side effects.
Keep Ayvakit (avapritinib) out of reach of visitors, children, or pets. Anticancer medications can be harmful to people who handle or come in contact with them.
Ayvakit (avapritinib) 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.
Risk factors: History of swollen or ruptured blood vessels (aneurysms) | Previous stroke or brain bleeds within the past year | Taking blood thinners | Low platelet levels
Bleeding in the brain is a rare but serious side effect of Ayvakit (avapritinib). Make sure to share your complete medical history and medication list with your oncology care team. Previous strokes, brain bleeds, or swollen or ruptured blood vessels (aneurysms) and treatment with blood thinners can raise your risk of having bleeding in the brain while you’re taking Ayvakit (avapritinib).
If you’re taking Ayvakit (avapritinib) for advanced systemic mastocytosis, you’ll need to have your blood drawn to check your platelet levels before you start treatment. You’ll also get them checked every 2 to 4 weeks while you’re taking the medication. Having low platelet levels can put you at risk for bleeding in the brain. If your platelet levels get too low, your oncologist will stop your Ayvakit (avapritinib) treatment for a while and restart it at a lower dose once your platelet levels normalize.
Get medical help right away if you develop any symptoms of a brain bleed, such as a severe headache, confusion, nausea, repeated vomiting, or changes in vision, while you’re taking Ayvakit (avapritinib). You’ll have to stop taking the medication if you have a brain bleed during treatment.
Risk factors: High Ayvakit (avapritinib) dose | Older age
People who take Ayvakit (avapritinib) can have a variety of side effects affecting the nervous system. These side effects can include confusion, forgetfulness, and speaking problems.
During clinical studies, these side effects were more common in people who took high doses of Ayvakit (avapritinib). Some people noticed these side effects within 2 to 4 months (and sometimes as early as a day) of starting the medication. Usually, the symptoms went away about 2 months after lowering the dose, pausing, or stopping treatment.
Let your healthcare team know if you have any new or worsening drowsiness, forgetfulness, problems concentrating, or problems with speaking while you’re taking Ayvakit (avapritinib). Avoid driving or doing anything that you need to concentrate on until a healthcare professional examines you. You might need to take a break from Ayvakit (avapritinib) so that you can recover from these side effects. Once your symptoms improve, you might be able to restart Ayvakit (avapritinib) at a lower dose.
Based on findings from animal studies, it’s possible for Ayvakit (avapritinib) to harm to an unborn baby if it’s taken during pregnancy. You might need to take a pregnancy test before starting treatment to make sure you’re not pregnant. Use effective birth control, such as birth control pills or condoms, while you’re taking Ayvakit (avapritinib) and for at least 6 weeks after your last dose if you’re sexually active. Let your oncologist know if you or your partner gets pregnant or plans to become pregnant while you’re taking Ayvakit (avapritinib).
Gastrointestinal stromal tumor (GIST) with PDGFRA mutations: The typical dose is 300 mg by mouth once daily.
Indolent systemic mastocytosis: The typical dose is 25 mg by mouth once daily.
Advanced systemic mastocytosis: The typical dose is 200 mg by mouth once daily.
Your oncologist might lower your dose if you have side effects from the medication (e.g., nausea, abnormal blood test results). They might also lower your dose if you have severe liver problems.
Gastrointestinal stromal tumor (GIST) with PDGFRA mutations (can’t be treated with surgery or has spread to other parts of the body)
Indolent (mild) or advanced form of systemic mastocytosis
Acute myeloid leukemia (AML) with a specific mutation (FLT3-positive)
Philadelphia chromosome-positive chronic myeloid leukemia (Ph+ CML)
Ph+ acute lymphoblastic leukemia (Ph+ ALL)
Myelodysplastic or myeloproliferative diseases (MDS/MPD)
Aggressive systemic mastocytosis (ASM)
Hypereosinophilic syndrome (HES) or chronic eosinophilic leukemia (CEL)
Dermatofibrosarcoma protuberans (DFSP)
Gastrointestinal stromal tumors (GIST)
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