INTRODUCTION
aggressive malignancy, EWS, toxicity, Ewing sarcoma
EWING SARCOMA
Ewing sarcoma (EWS) is a rare, aggressive malignancy of bone and soft tissue affecting adolescents and young adults.Several lines of evidence have suggested that IGF‐1R signaling is important in EWS. EWS cells are known to have high IGF‐1R expression and multiple early Cyclin‐dependent kinase 4 (CDK4) has been implicated as a genomic vulnerability in EWS. EWS harbors a superenhancer at the cyclin D1 (Given these preclinical findings, we designed a phase 2 clinical trial of the novel–novel combination of palbociclib (CDK4/6 inhibitor) and ganitumab (IGF‐1R inhibitor) for patients with relapsed or refractory EWS. The primary objectives were to assess the overall response rate to this combination and to assess toxicity in this patient population.