Tumor lysis syndrome (TLS), including
hyperuricemia, is a frequent serious complication in patients with
hematologic malignancies. This study in Japanese patients evaluated the efficacy, safety, and pharmacokinetic profile of
rasburicase in pediatric patients with
hematologic malignancies. Patients aged <18 years at high risk for TLS, with newly diagnosed
hematologic malignancies, were randomized to intravenous
rasburicase 0.15 mg/kg/day (n = 15) or 0.20 mg/kg/day (n = 15) for 5 days.
Chemotherapy was started 4-24 h after the first
rasburicase dose. Response was defined as a reduction in plasma
uric acid to < or = 6.5 mg/dL (patients <13 years) or < or = 7.5 mg/dL (patients > or = 13 years) by 48 h after the first administration, lasting until 24 h after the final administration. Response rates were 93.3 and 100% with
rasburicase 0.15 and 0.20 mg/kg/day, respectively.
Uric acid levels declined rapidly within 4 h of starting
rasburicase administration in both groups. Most adverse events were related to the underlying
chemotherapy regimens. Two
hypersensitivity reactions, including grade 1/2
pruritus, were considered to be related to
rasburicase.
Rasburicase is effective and well tolerated for the management of
hyperuricemia in Japanese pediatric patients at high risk of developing TLS.