A retrospective observational study of a low fixed-dose rasburicase protocol for the treatment of tumor lysis syndrome in adults

Abstract

Introduction Tumor lysis syndrome is an oncologic emergency characterized by hyperuricemia. Previous studies have demonstrated that a fixed-dose strategy of rasburicase is as effective as the FDA approved weight-based dose. Albany Medical Center employs rasburicase 1.5 mg in patients with a uric acid (UA) between 8 and 12 mg/dL and 3 mg for UA above12 mg/dL.We aimed to evaluate the UA lowering effectiveness and provider adherence to the institutional protocol, as well as the cost-efficiency of this dosing strategy. Methods This is a single center, retrospective, cohort study. The electronic medical record was used to identify patients receiving rasburicase and to collect baseline demographic and laboratory data. The fixed-dose strategies of rasburicase 1.5 mg and 3 mg were compared in their degree of UA reduction and clinical outcomes. Cost-savings of fixed-dosing was compared to the FDA-approved weight-based dose. Results Mean UA reduction in the 1.5 mg group (n = 49) from baseline to 24 hours was 2.88 ± 0.88 mg/dL (p < 0.0001) and 4.83 ± 1.39 mg/dL (p < 0.0001) in the 3 mg group (n = 105). A subgroup analysis of patients who received per protocol initial doses of rasburicase showed a mean reduction in UA from baseline to 24 hours of 2.83 ± 0.62 mg/dL in the 1.5 mg group (n = 42) and 6.12 ± 1.87 mg/dL in the 3 mg group (n = 42). Using a low fixed-dose approach resulted in a cost-savings of $138,077.30 annually. Conclusion Low fixed-dose rasburicase was an effective treatment, with a dose of 1.5 mg being sufficient to reach a goal UA of less than 8 mg/dL for serum UA levels below 12 mg/dL, while a 3 mg dose is appropriate for levels above 12 mg/dL. Cost analysis indicates this strategy is more cost-efficient than the FDA-approved weight-based dose.