Ripretinib (QINLOCK™) is a novel type II tyrosine switch control inhibitor being 
developed by Deciphera Pharmaceuticals for the treatment of KIT proto-oncogene 
receptor tyrosine kinase (KIT)-driven and/or platelet derived growth factor 
receptor A (PDGFRA)-driven cancers, including gastrointestinal stromal tumour 
(GIST). Ripretinib inhibits KIT and PDGFRA kinase, including wild-type, primary 
and secondary mutations, as well as other kinases, such as PDGFRB, TIE2, VEGFR2 
and BRAF. In May 2020, oral ripretinib received its first approval in the USA 
for the treatment of adult patients with advanced GIST who have received prior 
treatment with ≥ 3 kinase inhibitors, including imatinib. The US FDA, Health 
Canada and the Australian Therapeutic Goods Administration collaborated on the 
review of the ripretinib new drug application in this indication as part of 
Project Orbis; regulatory review in Australia and Canada is ongoing. Clinical 
development for GIST, solid tumours and systemic mastocytosis is underway in 
several countries worldwide. This article summarizes the milestones in the 
development of ripretinib leading to this first approval for the treatment of 
advanced GIST.