title: Single 4.5 mg fixed-dose of rasburicase for hyperuricemia associated with tumor lysis syndrome.
abstract: Rasburicase is a recombinant urate oxidase enzyme administered for treatment of hyperuricemia associated with tumor lysis syndrome. Studies demonstrate effectiveness of single fixed-dose rasburicase as compared to the FDA-approved dose of 0.2 mg/kg intravenously daily for up to five days. Doses in these studies range from 1.5 mg to 7.5 mg. Our study evaluated outcomes in patients who received single 4.5 mg fixed-dose rasburicase. This retrospective, IRB-approved chart review evaluated adult oncology subjects who received fixed-dose rasburicase between January 2007 and April 2014. The primary outcome was percentage of patients with normalization of uric acid (level <8 mg/dL within 24 h) after a single 4.5 mg fixed-dose of rasburicase. Secondary objectives were incidence of initial failure of fixed-dose rasburicase and normalization of uric acid in overweight (body mass index ≥25 kg/m2) versus non-overweight patients. Initial failure was defined as need for additional doses or progression to dialysis within one week of the initial fixed-dose. In the 128 patients included, the mean baseline uric acid level was 14.84 mg/dL. Of the 112 patients with a follow-up uric acid level, 68% achieved normalization within 24 h of rasburicase administration. Thirty-eight patients received additional treatment: 10 received additional dose(s) and 28 underwent dialysis. Normalization of uric acid in overweight versus non-overweight patients was 66% and 73%, respectively. Overall, a single 4.5 mg fixed-dose of rasburicase effectively normalized uric acid in 68% of patients within 24 h. Further studies are needed to determine the optimal single fixed-dose necessary for treatment response across all patients.
authors.affiliation: Department of Pharmacy, Cleveland Clinic, OH, USA.
authors.forename: Kajal S
authors.initials: KS
authors.lastname: Patel
authors.affiliation: Department of Pharmacy, Cleveland Clinic, OH, USA.
authors.forename: Jessica E
authors.initials: JE
authors.lastname: Lau
authors.affiliation: Department of Pharmacy, Cleveland Clinic, OH, USA.
authors.forename: Anthony S
authors.initials: AS
authors.lastname: Zembillas
authors.affiliation: Department of Pharmacy, Cleveland Clinic, OH, USA.
authors.forename: Erika M
authors.initials: EM
authors.lastname: Gallagher
mesh_terms: D000368:Aged; D018450:Disease Progression; D005260:Female; D006074:Gout Suppressants / Q000008:administration & dosage*; D006801:Humans; D033461:Hyperuricemia / Q000097:blood / Q000188:drug therapy* / Q000209:etiology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000097:blood / Q000150:complications*; D006435:Renal Dialysis; D019233:Retreatment; D012189:Retrospective Studies; D017211:Treatment Failure; D015275:Tumor Lysis Syndrome / Q000150:complications*; D014503:Urate Oxidase / Q000008:administration & dosage*; D014527:Uric Acid / Q000097:blood
chemical_list: D006074:Gout Suppressants; C469709:rasburicase; D014527:Uric Acid; D014503:Urate Oxidase
keywords: Rasburicase; hyperuricemia; tumor lysis syndrome; uric acid