Advanced Systemic Mastocytosis Treatment Study

Clinical Trial Title

Pathfinder trial: An open-label, single arm, phase 2 study to evaluate Eeficacy and safety of avapritinib, a selective KIT mutation-targeted tyrosine kinase inhibitor, in patients with advanced systemic mastocytosis.

National Clinical Trial Number:


Clinical Trial Protocol Description:

Aggressive Systemic Mastocytosis (ASM), Systemic Mastocytosis with an Associated Neoplasm (SM-AHN), and Mast Cell Leukemia (MCL) are disorders where abnormal mast cells accumulate in many organs and in bone marrow and cause abnormal organ function. Mast cells are a type of white blood cell that is part of the immune system. They are found in the skin, bones, joints, lymph nodes, liver, spleen, and gastrointestinal tract. When increased in number or abnormal in function they give off chemicals such as histamine that can cause flushing (a hot, red face), itching, abdominal cramps, muscle pain, nausea, vomiting, diarrhea, low blood pressure, and shock. 

SM-AHN is a rare condition in which too many mast cells build up in certain tissues and organs in the body, including the bone marrow, lymph nodes, bone, liver, spleen, and small intestine, and may damage them. In systemic mastocytosis with associated hematologic neoplasm, this mast cell buildup occurs together with another blood disorder, usually a myelodysplastic syndrome, myeloproliferative disorder, or acute myeloid leukemia (AML).

Avapritinib is an investigational drug being developed by Blueprint Medicines Corporation to treat all forms of mastocytosis. It is a type of drug called a tyrosine kinase inhibitor and acts by targeting a protein called KIT, which is abnormal in more than 90% of patients with SM. It is an oral drug that is taken continuously, once a day, in a 28-day cycles.

Clinical Trial Eligibility Criteria:

In order to participate you must meet the following criteria:

  • Are 18 years of age or older.
  • Have been diagnosed with aggressive systemic mastocytosis or systemic mastocytosis with an associated hematologic neoplasm of non-mast-cell lineage.
  • Have at least one of the following measurable C-findings: cytopenias; symptomatic ascites or pleural effusion requiring medical intervention; abnormalities in your bilirubin, AST, ALT, or alkaline phosphatase; hypoalbuminemia; a spleen that is palpable 5 centimeters or more below the left coastal margin; transfusion-dependent anemia; transfusion-dependent thrombocytopenia; or more than 10% weight loss over 24 weeks.
  • Aree able to swallow pills.

You will be excluded from the study if any of the following criteria apply to you:

  • Have received treatment with avapritinib before.
  • Have received cytoreductive therapy, radiotherapy, hematopoietic growth factor, or had a major surgical procedure within 14 days of the first dose of avapritinib.
  • Have a history of seizure disorder or a cerebrovascular accident or transient ischemic attacks.
  • Have clinically significant, uncontrolled cardiovascular disease.

This is a partial list of eligibility requirements. To inquire about your eligibility, please call the contact number provided. If you wish to inquire via email, please include the title of the study in your message.

Study Details

Clinical Trial Investigator

Celalettin Ustun, MD

Contact Information

Katharine Szubski, RN