Avapritinib (Ayvakit™) improves overall survival and other clinical outcomes, compared to real-world data on prior best available therapies, in patients with advanced systemic mastocytosis (SM), according to new analyses presented at the European Hematology Association (EHA) 2022 Congress.

According to the results of the analyses, patients treated with avapritinib had 41% and 68% reductions in the risk of death compared to patients treated with 2 other common SM treatments, midostaurin and cladribine, respectively.

Moreover, avapritinib treatment reduced the risk of death by 58% compared to the best available therapy in patients with SM with an associated hematological neoplasm, according to a press release from Blueprint Medicines, which developed the treatment.

When administered at a dose of 200 mg or less once a day, avapritinib reduced the risk of treatment discontinuation by 64% compared to the best available therapy in patients with advanced SM. The maximum percent reduction in serum tryptase levels at this dose was 85%, compared to 9% for the best available therapy, Blueprint reported.

Read more about the types of systemic mastocytosis

In the press release, Andreas Reiter, MD, the leader of the Centre of Excellence for Myeloproliferative Neoplasms at University Medical Centre, Heidelberg University in Mannheim, Germany, said, “These results are highly meaningful for this patient population, which has a significant disease burden and limited treatment options.”

SM is characterized by the presence of focal and/or diffuse infiltrates of neoplastic mast cells in the bone marrow, liver, spleen, and gastrointestinal tract.

Avapritinib is a kinase inhibitor approved by the US Food and Drug Administration (FDA) to treat adults with advanced SM, including aggressive SM, SM with an associated hematological neoplasm, and mast cell leukemia. The treatment is also approved by the European Commission (EC) for the same indications after trying at least 1 systemic therapy.


Blueprint Medicines reports continued progress toward goal of transforming treatment of systemic mastocytosis. News release. Blueprint Medicines Corporation; June 9, 2022.