Background

EWS is a bone tumor that occurs most often in adolescents. It can also arise outside of the bone (in soft tissue), is often aggressive, and can spread to distant sites. EWS is the second most common primary bone tumor in children and accounts for approximately 2% of all childhood cancer diagnoses; 200-250 children and adolescents are diagnosed in the United States annually.

Current treatment of patients with EWS consists of systemic chemotherapy often with surgery and/or radiation therapy for local tumor control. However, clinical outcomes for EWS have not significantly improved over the last few decades and current therapies are associated with considerable toxicities. mAb-based anti-cancers have rapidly emerged as a preferred anti-cancer approach. A mAbs’ ability to