CD19 and acute lymphoblastic leukemia: The indication according to the European Medicines Agency (EMA) limits the use of blinatumomab to pediatric patients aged one year or older with Philadelphia chromosome negative CD19 positive B-precursor ALL, which is refractory or in relapse after receiving at least two prior therapies or in relapse after receiving prior allogeneic hematopoietic stem cell transplantation (HSCT).