PDGFRB and Ewing sarcoma: Regorafenib, which targets RET, PDGFR-β, KIT and VEGFRs, in adult patients with advanced Ewing sarcoma demonstrated short-term benefit with 56% of patients in the treatment arm vs 7.7% of patients in the placebo arm progression-free at 8 weeks, with a median PFS of 11.4 vs 3.9 weeks when used as monotherapy [187].