A Phase 2/3 Study of BLU-263 in Patients with Indolent Systemic Mastocytosis or Monoclonal Mast Cell Activation Syndrome

Abstract

Systemic mastocytosis (SM) is a rare, clonal mast cell neoplasm driven by the KIT D816V mutation in ∼95% of cases. Indolent SM (ISM) is characterized by mast cell aggregates in skin, bone marrow, and multiple internal organs, and is often associated with chronic, debilitating, and potentially life-threatening symptoms. Monoclonal mast cell activation syndrome (mMCAS) is a clonal mast cell expansion, defined by the presence of 1 or 2 minor World Health Organization SM criteria, including D816V KIT mutation.