A systematic literature review of disease burden and clinical efficacy for patients with relapsed or refractory acute myeloid leukemia

Abstract

Acute myeloid leukemia (AML) is a rapidly progressive hematological malignancy that is difficult to cure. The prognosis is poor and treatment options are limited in case of relapse. A comprehensive assessment of current disease burden and the clinical efficacy of non-intensive therapies in this population are lacking. We conducted two systematic literature reviews (SLRs). The first SLR (disease burden) included observational studies reporting the incidence and economic and humanistic burden of relapsed/refractory (RR) AML. The second SLR (clinical efficacy) included clinical trials (phase II or later) reporting remission rates (complete remission [CR] or CR with incomplete hematologic recovery [CRi]) and median overall survival (mOS) in patients with RR AML or patients with de novo AML who are ineligible for intensive chemotherapy. For both SLRs, MEDLINE^®/Embase^® were searched from January 1, 2008 to January 31, 2020. Clinical trial registries were also searched for the clinical efficacy SLR. After screening, two independent reviewers determined the eligibility for inclusion in the SLRs based on full-text articles. The disease burden SLR identified 130 observational studies. The median cumulative incidence of relapse was 29.4% after stem cell transplant and 46.8% after induction chemotherapy. Total per-patient-per-month costs were $28,148-$29,322; costs and health care resource use were typically higher for RR versus non-RR patients. Patients with RR AML had worse health-related quality of life (HRQoL) scores than patients with de novo AML across multiple instruments, and lower health utility values versus other AML health states (i.e. newly diagnosed, remission, consolidation, and maintenance therapy). The clinical efficacy SLR identified 50 trials (66 total trial arms). CR/CRi rates and mOS have remained relatively stable and low over the last 2 decades. Across all arms, the median rate of CR/CRi was 18.3% and mOS was 6.2 months. In conclusion, a substantial proportion of patients with AML will develop RR AML, which is associated with significant humanistic and economic burden. Existing treatments offer limited efficacy, highlighting the need for more effective non-intensive treatment options.