(A) KIT secondary mutations did not significantly affect the number of partial responses between treatments arms. Avapritinib efficacy was similar between primary KIT exon 9 and 11 mutations (B), whereas regorafenib trended to be more effective in patients with a primary exon 11 mutation (C). (D) Avapritinib had greater efficacy in patients with a primary PDGFRA exon 18 D842V mutation than regorafenib. CI, confidence interval; mPFS, median progression-free survival; NE, not estimable; PD, progressive disease; PR, partial response; SD, stable disease.