ISM

For U.S. residents only ages 18+

ISM

AdvSM

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What to Know About Indolent Systemic Mastocytosis (ISM)

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What is indolent systemic mastocytosis?

ISM is a rare disease that affects the production and accumulation of mast cells, a type of white blood cell.

Normally, your body makes mast cells as part of your immune response, but a buildup of mast cells in different parts of the body can lead to symptoms similar to severe allergic reactions.

What causes ISM?

In about 95% of cases, ISM is thought to be caused by a gene mutation called KIT D816V.

Can ISM progress to AdvSM?

It's possible for a small number of ISM cases to progress to more advanced forms of systemic mastocytosis. Studies have reported that ISM may progress to advanced systemic mastocytosis (AdvSM) in approximately 3-4% of patients.

How many people have ISM?

Systemic mastocytosis (SM) is a rare condition that affects around 1 in 10,000 patients. The most common form of SM is indolent systemic mastocytosis (ISM), which accounts for around 75-90% of cases of SM.

Is ISM cancer?

Systemic mastocytosis involves the uncontrolled growth of mast cells that build up in the bone marrow and other organs. It is considered a form of cancer. However, ISM is an indolent, non-advanced form of SM and usually has less mast cell buildup compared to advanced forms of SM.

How is ISM diagnosed?

ISM is diagnosed by a doctor who may:

  • Take biopsies (bone and/or organ)
  • Measure signs of excess mast cells
  • Test for KIT D816V gene mutation
  • Test for serum tryptase
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What is KIT D816V testing?

A KIT D816V blood test may be helpful to aid in the diagnosis of patients who are being evaluated for ISM. Since the gene mutation is found in approximately 95% of ISM cases, measurement of this genetic marker can help screen for ISM. There are different types of KIT tests available that vary in sensitivity. High-sensitivity tests may be required to detect the mutation. There are other tests that may be helpful in diagnosing ISM; talk to your doctor about what testing might be most useful for you.

What are some of the common symptoms of ISM?

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Skin lesions and rash

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Potentially severe allergic reactions including anaphylaxis

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Nausea, vomiting and diarrhea

Other symptoms

Each patient with ISM may experience different symptoms in different ways. Several symptoms are associated with ISM, including:

  • Brain fog
  • Dizziness
  • Headache
  • Fatigue
  • Flushing
  • Bone pain
  • Itching
  • Spots on the skin
  • Abdominal pain
  • Diarrhea
  • Nausea

Talk to your doctor about your symptoms and for medical advice.

Symptom triggers

ISM symptoms may occur in response to certain triggers. These can differ from person to person, but some common ISM symptom triggers may include:

  • Alcohol
  • Changes in temperature
  • Certain foods
  • Anxiety and stress
  • Skin irritation
  • Certain medications
  • Exercise
  • Insect stings
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How may ISM symptoms impact you?

Since symptoms may occur across a wide variety of organ systems, keeping track of them can help you understand how ISM may impact your life. Always remember to discuss your symptoms with your doctor.

Approaches to treating ISM

Historically, patients managed and addressed individual symptoms. For example, patients may have treated skin reactions or gastrointestinal symptoms with certain types of antihistamines. Additionally, AYVAKIT is the only FDA-approved treatment for adults with ISM that may help reduce symptoms.

Living with ISM symptoms

You may have been managing symptoms with multiple treatments that help relieve individual symptoms. Before AYVAKIT, there were no FDA-approved therapies for ISM.

What doctors treat ISM?

Patients may see various types of doctors, including allergists, immunologists, hematologists, or oncologists. However, these aren’t the only doctors who may treat ISM.

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Discover what ISM symptom relief may look like

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Want more information about AYVAKIT?

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INDICATION

WHAT IS AYVAKIT® (avapritinib)?

AYVAKIT® (avapritinib) is a prescription medicine used to treat adults with indolent systemic mastocytosis (ISM). AYVAKIT is not recommended 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. Bleeding in the brain has not been seen in people treated with AYVAKIT for ISM.

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:

  • have a 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 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 ISM include: swelling around your eyes, dizziness, swelling of your arms and legs, and flushing.

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.

Please see the full Prescribing Information and Patient Information for AYVAKIT.

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. Bleeding in the brain has not been seen in people treated with AYVAKIT for ISM.

INDICATION

WHAT IS AYVAKIT® (avapritinib)?

AYVAKIT® (avapritinib) is a prescription medicine used to treat adults with indolent systemic mastocytosis (ISM). AYVAKIT is not recommended in people with low platelet counts (less than 50 X 109/L).

It is not known if AYVAKIT is safe and effective in children.

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

INDICATION

WHAT IS AYVAKIT® (avapritinib)?

AYVAKIT® (avapritinib) is a prescription medicine used to treat adults with indolent systemic mastocytosis (ISM). AYVAKIT is not recommended 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. Bleeding in the brain has not been seen in people treated with AYVAKIT for ISM.

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:

  • have a 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 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 ISM include: swelling around your eyes, dizziness, swelling of your arms and legs, and flushing.

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.

Please see the full Prescribing Information and Patient Information for AYVAKIT.