Advances in the treatment of relapsed/refractory acute lymphoblastic leukemia: a case study compendium

Abstract

Acute lymphoblastic leukemia (ALL) is a heterogeneous hematologic malignancy characterized by proliferation of immature lymphoid cells throughout the bone marrow and peripheral blood. Most cases are diagnosed before the age of 20 years. Adults have a worse prognosis than children. Approximately half of adult ALL patients relapse after their initial treatment. There is no standard treatment for ALL; strategies vary according to the patient’s age, comorbidities, and Philadelphia chromosome status. Regimens used in pediatric patients are being adapted for use in adults. Frontline management can include hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone alternating with cycles of high-dose methotrexate and cytarabine (hyper-CVAD) and the Berlin-Frankfurt-Münster regimen. Relapsed/refractory patients have several options, including a regimen consisting of fludarabine, high-dose cytarabine, and granulocyte colony–stimulating factor (FLAG); tyrosine kinase inhibitors; and chemotherapy. The US Food and Drug Administration recently approved 3 therapies for these patients: clofarabine, nelarabine, and vincristine sulfate liposome injection, a modified formulation of vincristine that allows the drug to be administered at a higher dosage. Several novel strategies are currently under investigation, including the monoclonal antibody blinatumomab, a bispecific T-cell engager that targets the B-cell–specific antigen CD19 and activates T cells to exert cytotoxic activity against the target B cell. This clinical roundtable monograph features case studies that illustrate important points in the management of adult patients with relapsed/refractory ALL.