[CAS NO. 1442472-39-0]  Ripretinib (DCC-2618)

DCC-2618 is a switch-control type II inhibitor of KIT, which arrests KIT in an inactive state, regardless of activating mutations, such as KIT D816V. In CHO cells transiently transfected with both single and double (primary/secondary) KIT mutants, DCC-2618 robustly inhibits exon 17, exon 9/13, exon 9/14, and exon 9/17 KIT mutants, as well as exon 11/17 KIT mutants, including exon 17 D816V, D816G, D820A, D820E, D820Y, N822K, N822Y, N822H, and Y823D primary or secondary mutations. DCC-2618 inhibits the proliferation and survival of various human mast cell lines (HMC-1, ROSA, MCPV-1) as well as primary neoplastic mast cells obtained from patients with advanced systemic mastocytosis (IC50 <1 μM). DCC-2618 decreases growth and survival of primary neoplastic eosinophils obtained from patients with systemic mastocytosis or eosinophilic leukemia, leukemic monocytes obtained from patients with chronic myelomonocytic leukemia with or without concomitant systemic mastocytosis, and blast cells obtained from patients with acute myeloid leukemia. Furthermore, DCC-2618 suppresses the proliferation of endothelial cells and may have additional drug effects on systemic mastocytosis-related angiogenesis. DCC-2618 downregulates IgE-mediated histamine release from basophils and tryptase release from mast cells.