To Evaluate the Efficacy and Safety of Naxitamab in Patients With Refractory Ewing's Sarcoma (Butterfly)

Naxitamab will be used only in a hospital setting and must be administered under the supervision of a doctor with experience in the use of oncological therapies. The medicinal product must be administered by a healthcare professional prepared to deal appropriately with severe allergic reactions, including anaphylaxis, in an environment that provides immediate, full access to resuscitation. The patient should have 2 well-functioning IV accesses before any naxitamab treatment is initiated. The solution should be administered through a peripheral or central intravenous catheter. Other concomitant intravenous medicinal products should be administered through separate intravenous access. Before the start of each infusion, premedication will be carried out.