Because they were excluded from most of the clinical trials of non-recombinant urate oxidase and rasburicase, the safety of rasburicase in this population is not known, though preliminary data indicates that the drug is safe. The primary objective of this study is to estimate the proportion of grade 3 or 4 allergic reactions to rasburicase in patients with a history of asthma or severe allergy (to antigens other than rasburicase or other urate oxidases) treated with rasburicase for the prevention or treatment of malignancy or chemotherapy-induced hyperuricemia. Patients at risk of tumor lysis syndrome with a history of asthma/atopy will be treated with rasburicase according to standard practice and observed for allergic reactions.
