Background: Adolescent and young adults (AYA) with acute lymphoblastic leukemia (ALL) represent a unique complex group, particularly, with respect to the therapeutic approach. The current trend is to treat AYAs with pediatric ALL treatment regimens, which has been associated with higher survival rates. Blinatumomab is a bispecific monoclonal antibody that binds to CD19 antigen on B-lymphoblasts and CD3 on T cells. Favorable outcomes regarding the utilization of blinatumomab have been obtained in both children and adults, for the treatment of relapsed/refractory (r/r) and minimal residual disease (MRD)-positive B-cell precursor ALL (B-ALL). Nevertheless, the safety and efficacy of blinatumomab in early stages of the disease as frontline therapy is not fully elucidated. Case Description: A 20-year-old male was referred to our hospital in critical condition for untreated newly diagnosed Phi...