Blueprint Medicines, the developers of avapritinib (Ayvakit™), announced they plan to report topline data from a clinical trial of the therapy in patients with nonadvanced systemic mastocytosis called PIONEER this month.

The company also reported that the primary endpoint of the second part of that trial was modified upon request by the US Food and Drug Administration (FDA) and is now the mean change in total symptom score. 

“We are now one year into the Ayvakit launch in advanced systemic mastocytosis (SM) and continue to see a significant expansion of our prescriber base as well as strong patient demand, reinforcing our conviction in the growth opportunity in SM,” Kate Haviland, the chief executive officer of Blueprint Medicines, said in a press release.

“We are on track to announce topline data from our registration-enabling PIONEER trial in August, which will catalyze our ability to bring Ayvakit’s transformative potential to patients living with non-advanced SM.”

Read more about systemic mastocytosis

Blueprint plans to submit a supplemental New Drug Application to the FDA for avapritinib for the treatment of nonadvanced systemic mastocytosis later this year.

Avapritinib significantly improves overall survival in patients with advanced systemic mastocytosis compared to prior best available therapies including midostaurin and cladribine, according to data presented at the European Hematology Association (EHA) 2022 Congress.

Systemic mastocytosis is characterized by the proliferation and accumulation of excessive amounts of pathologic mast cells in different tissues and organs, causing damage.

Avapritinib is a receptor tyrosine kinase inhibitor. It works by blocking the activity of platelet-derived growth factor receptor A, which is found on the surface of mast cells, thereby controlling their growth. It is already approved by the FDA to treat adults with advanced systemic mastocytosis. It can also be used to treat some patients with gastrointestinal stromal tumors.


Blueprint Medicines reports second quarter 2022 results. News release. Blueprint Medicines; August 2, 2022.