Long-term data from the PIONEER study show a sustained effect of avapritinib (Ayvakit) in indolent systemic mastocytosis (ISM).[2][5] These results were presented at the annual meeting of the American Academy of Allergy, Asthma and Immunology (AAAAI).[1] Avapritinib is a KIT inhibitor that is administered at a recommended dose of 25 mg orally once daily on an empty stomach in patients with ISM.[2][3][5] In part 2 of the PIONEER study, 141 patients received this 25 mg dose.[2] Effects on cognitive function occurred in 2.8% of patients with ISM.[2][5] The study supports the durability of treatment response in this type of systemic mastocytosis.[1]