Low fixed-dose rasburicase achieves target UA levels in treatment of tumour lysis syndrome

Treatment with rasburicase at low fixed dose is effective in adults with tumour lysis syndrome, results of a study have shown.

Specifically, a 1.5-mg dose is enough to reach a goal uric acid (UA) level of <8 mg/dL for patients with serum UA levels of <12 mg/dL, while a 3-mg dose is sufficient for those with UA levels of >12 mg/dL.

“Cost analysis indicates this strategy is more cost-efficient than the FDA-approved weight-based dose,” the researchers noted.

In this single-centre, retrospective, cohort study, patients receiving rasburicase were identified and their baseline demographic and laboratory data were collated using the electronic medical record.

The researchers compared the fixed-dose strategies of rasburicase 1.5 and 3 mg in their degree of UA reduction and clinical outcomes. They also compared the cost-savings of fixed dosing with the FDA-approved weight-based dose.

Mean UA reduction from baseline to 24 hours was 2.88 mg/dL (p<0.0001) in the 1.5-mg group (n=49) and 4.83 mg/dL (p<0.0001) in the 3-mg group (n=105).

In the subgroup analysis of patients who received per protocol initial doses of rasburicase, the mean reduction in UA from baseline to 24 hours was 2.83 mg/dL in the 1.5-mg group (n=42) and 6.12 mg/dL in the 3-mg group (n=42).

Of note, use of a low fixed-dose approach led to cost-savings amounting to $138,077.30 annually.

“Tumour lysis syndrome is an oncologic emergency characterized by hyperuricaemia,” the researchers said. “Previous studies have demonstrated that a fixed-dose strategy of rasburicase is as effective as the FDA-approved weight-based dose.”