While HSND19 exhibited slightly lower IC50 in cell cultures and comparable efficacy in CCDC6-RET-dependent thyroid PDXs, KIF5B-RET-driven lung tumors in transgenic mice, and in B/KR(G810C)-luc extracranial tumors, only HSN748 displayed significant intracranial efficacy in B/KR(G810C)-luc brain tumors. This evidence concerns the gene RET and brain neoplasm.