PDGFRA and gastrointestinal stromal tumor: Ripretinib, a tyrosine switch-control inhibitor stabilizing the switch pocket in an inactive conformation, has been approved in the fourth-line setting and exhibited a broad activity against secondary KIT mutations resistant to IM (i.e., exon 13 (V654A), exon 14 (T670I), and exon 17/18 (D816V, A829P) [12,13], whereas avapritinib exhibited activity against PDGFRA D842V and was approved for tumors with PDGFRA exon 18 mutations in any line of GIST treatment [14,15,16].