Introduction
The recommended dose of rasburicase for the prevention and treatment of tumour lysis syndrome (TLS) is 0.20 mg/kg/day for 5 to 7 days. Although growing evidence supports low fixed-dose regimens (3–6 mg), uncertainty remains regarding their ability to prevent progression to clinical TLS (CTLS), particularly in high-risk populations. To optimise safe, effective, and economical use, some institutions implement medicine governance strategies with specific criteria, risk stratification, and dosing stipulations. A single 3mg rasburicase dose costs AUD$400, versus AUD$14,935 for 7 days treatment for an 80 kg adult.
Aims
To evaluate laboratory TLS (LTLS) and CTLS outcomes following low fixed-dose rasburicase and characterise institutional prescribing criteria compliance.
Methods
A retrospective, single-centre, observational study was conducted of adults with haematological malignancies who received at least one dose of rasburicase between March 2017 and March 2025. Rasburicase indication, dosing, TLS outcomes, and prescribing criteria compliance were analysed using descriptive statistics.
Results
Among 144 patients, 114 (79%) were classified as high-risk for TLS and 99 (69%) received rasburicase prophylactically. Single low fixed-dose strategies predominated, with 61% receiving one dose (3 mg or 6 mg). Urate normalisation within 24 hours occurred in 92% of all patients and 97% of prophylaxis patients. Despite rapid biochemical response, 47/99 (47%) of prophylaxis patients demonstrated evidence of LTLS and 14/99 (14%) developed CTLS, of whom 9/14 (64%) had pre-existing kidney impairment. Prescribing criteria compliance was 85%, with non-compliance primarily attributed to early biochemical changes or urgent need for anti-cancer therapy.
Conclusions
Low fixed-dose rasburicase demonstrated clinical effectiveness and supports economic optimisation of TLS prophylaxis in high- and intermediate-risk patients and TLS treatment, with high compliance of institutional prescribing criteria. These findings support low fixed-dose rasburicase as a cost-effective strategy for optimising the use of a high-cost medicine, improving affordability and expanding access without compromising clinical outcomes.