Frequently Asked Questions
(FAQs)

AdvSM FAQs

Systemic Mastocytosis (SM) is a rare disorder in which excess mast cells build up in the body. Mast cells are a type of white blood cell that helps the immune system function normally and helps protect from disease. Mast cells are found in connective tissues throughout the body. In SM, a surplus of mast cells collects in the skin, bone marrow, digestive tract, or other body organs. When triggered, these excess mast cells release histamines and other chemicals that can cause symptoms similar to those that occur in an allergic reaction, as well as inflammation that may be severe enough to result in organ damage.

AdvSM is a type of systemic mastocytosis. AdvSM occurs when the buildup of mast cells causes damage to organs, which may affect how well they can work. There are different types of AdvSM:

  • Aggressive Systemic Mastocytosis (ASM)
  • Systemic Mastocytosis with another blood cell condition (called an Associated Hematologic Neoplasm or SM-AHN)
  • Mast Cell Leukemia (MCL)

AdvSM is caused by a mutation called KIT D816V that makes these abnormal mast cells grow out of control.

AdvSM can affect people differently. Some symptoms that have been reported by people living with AdvSM include:

  • Depression or anxiety
  • Brain fog, memory loss, or difficulty concentrating
  • Headaches
  • Flushing, itching, and hives
  • Abdominal pain or cramping
  • Diarrhea
  • Nausea
  • Acid reflux
  • Low blood pressure
  • Dizziness
  • Heart flutters or rapid heart rate
  • Chest pain
  • Severe whole-body allergic reactions (anaphylaxis)
  • Bone and muscle pain
  • Bone loss or weak and brittle bones
  • Extreme tiredness
  • Shortness of breath
  • Nasal congestion
  • Weight loss
  • Abnormal bloodwork
  • Organ damage or failure

To diagnose AdvSM, doctors will need to assess your medical history, current symptoms and may do a variety of tests to look for abnormal mast cells in your blood, bone marrow and other organs. They may also test mast cells for the KIT D816V mutation.

AdvSM is a rare condition where mast cells grow abnormally and out of control. Therefore, it is considered a type of cancer.

Across all types, systemic mastocytosis is estimated to occur in up to 1 in 5,000 adults,1-4 although fewer than that have AdvSM. Current estimates suggest around 1 in approximately 200,000 people worldwide are living with this condition.

AYVAKIT FAQs

Once you've been prescribed AYVAKIT, your doctor sends your prescription to an eligible pharmacy or to YourBlueprint®. The pharmacy will verify your insurance coverage and work directly with your healthcare provider to obtain prior authorization if needed. Then, when coverage is approved, your pharmacy will contact you to communicate your out-of-pocket costs and arrange for delivery or pickup of your medication.

Over 98% of all commercial insurance plans and 99% of Medicare plans offer coverage for AYVAKIT.*

*Data on coverage is as of September 2025.

Yes. YourBlueprint® offers financial assistance options to help qualifying patients throughout their treatment journey.

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References: 1. Bergstrom A, et al. Acta Oncol. 2024;63(1):44–50. 2. Brockow K, et al. Immunol Allergy Clin North Am. 2014;34(2):283–295. 3. Cohen SS, et al. Br J Haematol. 2014;166(4):521–528. 4. van Doormaal JJ, et al. J Allergy Clin Immunol. 2013;131(5):1430–1431.

INDICATION

WHAT IS AYVAKIT® (avapritinib)?

AYVAKIT® (avapritinib) is a prescription medicine used to treat adults with advanced systemic mastocytosis (AdvSM), including aggressive systemic mastocytosis (ASM), systemic mastocytosis with an associated hematological neoplasm (SM-AHN), and mast cell leukemia (MCL). AYVAKIT is not recommended for the treatment of AdvSM in people with low platelet counts (less than 50 x 109/L). It is not known if AYVAKIT is safe and effective in children.

IMPORTANT SAFETY INFORMATION

AYVAKIT® (avapritinib) may cause serious side effects, including:

Bleeding in your brain. Serious bleeding in the brain may happen during treatment with AYVAKIT and may lead to death. Stop taking AYVAKIT and tell your healthcare provider right away if you develop any symptoms such as severe headache, nausea, vomiting, vision changes, drowsiness, dizziness, confusion, or severe weakness on one or more side of your body. Your healthcare provider will check your platelet counts before and during treatment with AYVAKIT.

Cognitive effects. Cognitive side effects can happen during treatment with AYVAKIT and can be severe. Tell your healthcare provider if you develop any new or worsening cognitive symptoms including forgetfulness, confusion, getting lost, trouble thinking, drowsiness, trouble staying awake (somnolence), word finding problems, seeing objects or hearing things that are not there (hallucinations), or a change in mood or behavior.

Skin sensitivity to sunlight (photosensitivity). Your skin may be sensitive to the sun or other forms of light (photosensitivity) during treatment with AYVAKIT. Avoid or limit exposure to direct sunlight, sunlamps, and other sources of ultraviolet radiation during treatment and for 1 week after stopping treatment with AYVAKIT. Use sunscreen or wear clothes that cover your skin if you need to be out in the sun.

Before taking AYVAKIT, tell your healthcare provider about all of your medical conditions, including if you:

  • history of bulging or weakening of a blood vessel wall (aneurysm) or bleeding in your brain
  • have a history of stroke within the last year
  • have low platelet counts
  • have or have had liver problems
  • are pregnant or plan to become pregnant. AYVAKIT can cause harm to your unborn baby
  • Females who are able to become pregnant: Your healthcare provider should do a pregnancy test before you start AYVAKIT. You should use effective birth control (contraception) during treatment with AYVAKIT and for 6 weeks after the final dose of AYVAKIT. Talk to your healthcare provider about birth control methods that may be right for you. Tell your healthcare provider right away if you become pregnant or think you may be pregnant during treatment with AYVAKIT.
  • Males with female partners who are able to become pregnant should use effective birth control (contraception) during treatment and for 6 weeks after the final dose of AYVAKIT.
  • are breastfeeding or plan to breastfeed. It is not known if AYVAKIT passes into your breast milk. Do not breastfeed during treatment with AYVAKIT and for at least 2 weeks after the final dose of AYVAKIT. Talk to your healthcare provider about the best way to feed your baby during this time

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. AYVAKIT may affect the way other medicines work, and certain other medicines may affect how AYVAKIT works. Especially tell your healthcare provider if you take estrogen-containing hormonal birth control or medicines that prevent blood clots.

Do not drive or operate hazardous machinery if you have confusion or trouble thinking during treatment with AYVAKIT.

The most common side effects of AYVAKIT in people with AdvSM include: fluid retention or swelling, diarrhea, nausea, tiredness or weakness, and changes in certain blood tests.

Your healthcare provider may change your dose, temporarily stop, or permanently stop treatment with AYVAKIT if you develop certain side effects. AYVAKIT may cause fertility problems in females and males. Talk to your healthcare provider if this is a concern for you.

These are not all of the possible side effects of AYVAKIT. Call your doctor for medical advice about side effects. You are encouraged to report side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

AYVAKIT is available in 25-mg, 50-mg, 100-mg and 200-mg tablets.

Please click here to see the full Prescribing Information and Patient Information for AYVAKIT.

INDICATION & IMPORTANT SAFETY INFORMATION

AYVAKIT® (avapritinib) may cause serious side effects, including:

Bleeding in your brain. Serious bleeding in the brain may happen during treatment with AYVAKIT and may lead to death. Stop taking AYVAKIT and tell your healthcare provider right away if you develop any symptoms such as severe headache, nausea, vomiting, vision changes, drowsiness, dizziness,

INDICATION & IMPORTANT SAFETY INFORMATION

Warning: AYVAKIT® (avapritinib) may cause serious side effects, including bleeding in your brain, cognitive effects, skin sensitivity to sunlight (photosensitivity), harm to your unborn baby.

INDICATION & IMPORTANT SAFETY INFORMATION

Warning: AYVAKIT® (avapritinib) may cause serious side effects, including bleeding in your brain, cognitive effects, skin sensitivity to sunlight (photosensitivity), harm to your unborn baby.

INDICATION

WHAT IS AYVAKIT® (avapritinib)?

AYVAKIT® (avapritinib) is a prescription medicine used to treat adults with advanced systemic mastocytosis (AdvSM), including aggressive systemic mastocytosis (ASM), systemic mastocytosis with an associated hematological neoplasm (SM-AHN), and mast cell leukemia (MCL). AYVAKIT is not recommended for the treatment of AdvSM in people with low platelet counts (less than 50 x 109/L). It is not known if AYVAKIT is safe and effective in children.

IMPORTANT SAFETY INFORMATION

AYVAKIT® (avapritinib) may cause serious side effects, including:

Bleeding in your brain. Serious bleeding in the brain may happen during treatment with AYVAKIT and may lead to death. Stop taking AYVAKIT and tell your healthcare provider right away if you develop any symptoms such as severe headache, nausea, vomiting, vision changes, drowsiness, dizziness, confusion, or severe weakness on one or more side of your body. Your healthcare provider will check your platelet counts before and during treatment with AYVAKIT.

Cognitive effects. Cognitive side effects can happen during treatment with AYVAKIT and can be severe. Tell your healthcare provider if you develop any new or worsening cognitive symptoms including forgetfulness, confusion, getting lost, trouble thinking, drowsiness, trouble staying awake (somnolence), word finding problems, seeing objects or hearing things that are not there (hallucinations), or a change in mood or behavior.

Skin sensitivity to sunlight (photosensitivity). Your skin may be sensitive to the sun or other forms of light (photosensitivity) during treatment with AYVAKIT. Avoid or limit exposure to direct sunlight, sunlamps, and other sources of ultraviolet radiation during treatment and for 1 week after stopping treatment with AYVAKIT. Use sunscreen or wear clothes that cover your skin if you need to be out in the sun.

Before taking AYVAKIT, tell your healthcare provider about all of your medical conditions, including if you:

  • history of bulging or weakening of a blood vessel wall (aneurysm) or bleeding in your brain
  • have a history of stroke within the last year
  • have low platelet counts
  • have or have had liver problems
  • are pregnant or plan to become pregnant. AYVAKIT can cause harm to your unborn baby
  • Females who are able to become pregnant: Your healthcare provider should do a pregnancy test before you start AYVAKIT. You should use effective birth control (contraception) during treatment with AYVAKIT and for 6 weeks after the final dose of AYVAKIT. Talk to your healthcare provider about birth control methods that may be right for you. Tell your healthcare provider right away if you become pregnant or think you may be pregnant during treatment with AYVAKIT.
  • Males with female partners who are able to become pregnant should use effective birth control (contraception) during treatment and for 6 weeks after the final dose of AYVAKIT.
  • are breastfeeding or plan to breastfeed. It is not known if AYVAKIT passes into your breast milk. Do not breastfeed during treatment with AYVAKIT and for at least 2 weeks after the final dose of AYVAKIT. Talk to your healthcare provider about the best way to feed your baby during this time

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. AYVAKIT may affect the way other medicines work, and certain other medicines may affect how AYVAKIT works. Especially tell your healthcare provider if you take estrogen-containing hormonal birth control or medicines that prevent blood clots.

Do not drive or operate hazardous machinery if you have confusion or trouble thinking during treatment with AYVAKIT.

The most common side effects of AYVAKIT in people with AdvSM include: fluid retention or swelling, diarrhea, nausea, tiredness or weakness, and changes in certain blood tests.

Your healthcare provider may change your dose, temporarily stop, or permanently stop treatment with AYVAKIT if you develop certain side effects. AYVAKIT may cause fertility problems in females and males. Talk to your healthcare provider if this is a concern for you.

These are not all of the possible side effects of AYVAKIT. Call your doctor for medical advice about side effects. You are encouraged to report side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

AYVAKIT is available in 25-mg, 50-mg, 100-mg and 200-mg tablets.

Please click here to see the full Prescribing Information and Patient Information for AYVAKIT.