Rasburicase is a recombinant uricase used for the prevention and treatment of tumor lysis syndrome. It metabolizes uric acid into the more water-soluble allantoin, helping get rid of the excess uric acid that is released during tumor lysis syndrome. Tumor lysis syndrome is a dangerous condition that may occur during the treatment of leukemia and lymphoma, where there is massive cell death. This leads to the release of nucleic acids that are turned into uric acid, which may cause hyperuricemia and acute kidney injury.