Initiated Phase 1 trial of next-generation KIT inhibitor BLU-263 in healthy volunteers
Blueprint Medicines Corporation (NASDAQ: BPMC), a precision therapy company focused on genomically defined cancers, rare diseases and cancer immunotherapy, today announced updated clinical data from part 1 of the PIONEER trial showing robust and consistent clinical activity for avapritinib across multiple qualitative and quantitative measures of cutaneous disease in patients with indolent systemic mastocytosis (SM). Additional data showed avapritinib treatment resulted in deepening improvements in overall disease symptoms, as measured by the Indolent SM Symptom Assessment Form (ISM-SAF) total symptom score (TSS), and was well-tolerated through 24 weeks of follow-up. These data were presented today during the European Academy of Allergy and Clinical Immunology (EAACI) Digital Congress 2020.
SM is a rare disease driven by the KIT D816V mutation in nearly all patients and characterized by uncontrolled mast cell proliferation and activation. The disorder can lead to debilitating systemic, gastrointestinal and neurocognitive symptoms, including life-threatening anaphylaxis. Additional skin manifestations such as itching, flushing and pigmented skin lesions are common and can significantly impact quality of life. Avapritinib is a potent and highly selective inhibitor of D816V mutant KIT.
“Patients with indolent systemic mastocytosis often suffer from extensive skin lesions and severe mediator symptoms that can be life-threatening,” said Karin Hartmann, M.D., Professor of Medicine and Head of the Division of Allergy at the University of Basel and an investigator on the PIONEER trial. “The updated PIONEER trial data showed that patients treated with avapritinib had clinically meaningful reductions in mediator symptoms, patient-reported quality of life and mast cell burden across multiple measures. With further evidence that these reductions deepen over time, avapritinib has the potential to provide important clinical benefits to patients with this debilitating disease.”
“These promising data reinforce our commitment to rapidly advance development of avapritinib to meet persistent medical needs in indolent systemic mastocytosis, which are poorly addressed by a patchwork of available symptomatic therapies,” said Andy Boral, M.D., Ph.D., Chief Medical Officer at Blueprint Medicines. “Avapritinib was specifically designed to potently target the underlying disease driver of systemic mastocytosis and has the potential to fundamentally change the treatment of this disease.”
The presentation is available on-demand via the EAACI Digital Congress 2020 website at www.eaaci.org/eaaci-congresses/eaaci-2020.
Highlights from the EAACI Presentation of PIONEER Trial Data
Previously reported data from part 1 of the PIONEER trial showed that treatment with avapritinib was well-tolerated and resulted in robust and clinically meaningful improvements on measures of mast cell burden, disease symptoms and patient-reported quality of life through 16 weeks. Based on these data, avapritinib 25 mg once daily (QD) was selected as the recommended part 2 dose. Updated data on disease symptoms through 24 weeks and new skin assessment results were reported in the EAACI presentation.