Understanding Systemic mastocytosis

Systemic mastocytosis (SM) is a rare condition caused by the accumulation of mast cells in the body’s organs, such as the skin, bone marrow, liver, spleen and small intestines. Mast cells are an important type of immune cell that normally play a role in the body helping fight infection and triggering the allergic response. In systemic Mastocytosis, mast cells are released when they shouldn’t be, causing symptoms throughout the body.

Types of SM

Systemic mastocytosis is classified into 3 main types – indoltent SM, smoldering SM and advanced SM. Usually, indolent and smoldering SM are treated by a dermatologist or allergist, while advanced SM care is generally provided by a hematologist or oncologist. Across all these subtypes, up to 95% of people have a specific mutation (genetic alteration) in a gene called KIT. The mutation, known as KIT D816V, is believed to play a central role in the activation and accumulation of mast cells in people with systemic mastocytosis. Depending on the subtype of SM, symptoms and treatments can vary.

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Advanced SM

In advanced systemic mastocytosis, mast cells are inappropriately released, causing various symptoms in multiple organs, such as skin rash, abdominal pain, nausea and vomiting.

There are three different subtypes of advanced SM – aggressive SM, SM with an associated hematological neoplams and mast cell leukemia.

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Indolent or Smoldering SM

People with indolent and smoldering systemic mastocytosis can experience severe symptoms which often present as severe allergies, but can include rashes, GI problems, fatigue, “brain fog,” risk of anaphylaxis, bone pain, osteoporosis and more.

Clinical Trials for systemic mastocytosis

At Blueprint Medicines, we are conducting multiple studies researching an investigational drug called avapritinib to treat systemic mastocytosis. If you or someone you know could benefit from this research, please explore the following clinical trials to learn more.

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A clinical trial of avapritinib for people with advanced systemic mastocytosis.

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A double-blind clinical trial of avapritinib for people with indolent and smoldering systemic mastocytosis.

Informational Webinar on Avapritinib Clinical Trial Program in SM

On Thursday, September 26, 2019, Blueprint Medicines hosted a webinar for the systemic mastocytosis (SM) patient and caregiver community about avapritinib, an investigational medicine for people with SM.

Brenton Mar, Medical Director, Systemic Mastocytosis Program at Blueprint Medicines, shared an update on recent data presented at the 2019 European Hematology Association, as well as information on current clinical studies in SM. A replay is available by clicking below:

Patients who are interested in ongoing studies can contact the Blueprint Medicines study director at studydirector@blueprintmedicines.com or 1-617-714-6707 to learn more about opportunities to participate.

Additional information about the PATHFINDER and PIONEER trials for people with advanced, indolent, and smoldering SM can be viewed at https://www.blueprintclinicaltrials.com/sm/

The PATHFINDER and PIONEER clinical trials are currently being conducted at trial sites around the world, with additional sites being added.

Please note that a travel support program is available for participants at most trial sites to reduce out-of-pocket expenses and help ensure travel to the trial site is simple and comfortable. More information about travel support is provided by the trial site during the screening process.