API

Mechanism of Action

Protein kinases play important roles in cellular function, and their dysregulation can lead to carcinogenesis. Ripretinib inhibits protein kinases including wild type and mutant platelet-derived growth factor receptor A (PDGFRA) and KIT that cause the majority of gastrointestinal stromal tumor (GIST). In vitro, ripretinib has been shown to inhibit PDGFRB, BRAF, VEGF, and TIE2 genes.

Ripretinib binds to KIT and PDGFRA receptors with mutations on the exons 9, 11, 13, 14, 17 and 18 (for KIT mutations), and exons 12, 14 and 18 (for PDGFRA mutations). The “switch pocket” of a protein kinase is normally bound to the activation loop, acting as an “on-off switch” of a kinase. Ripretinib boasts a unique dual mechanism of action of binding to the kinase switch pocket as well as the activation loop, thereby turning off the kinase and its ability to cause dysregulated cell growth.

Indication

Ripretinib is indicated to treat adults diagnosed with advanced gastrointestinal stromal tumor (GIST) who have had prior therapy with at least 3 kinase inhibitors, including with imatinib