BACKGROUND: Rituximab is a chimeric, anti-CD20 monoclonal antibody registered 
for the treatment of B-cell malignancies and refractory rheumatoid arthritis in 
Australia. In addition to these approved indications, there has been growing 
interest in the use of off-label rituximab in the management of a variety of 
diseases.
AIMS: To determine the current usage of off-label rituximab in Australia, we 
collected nationwide data.
METHODS: Information regarding patients receiving rituximab for off-label 
indications was prospectively collected for a 6-month period from Australian 
public hospitals. Data recorded included clinical indication, dosing schedule, 
previous therapy and efficacy assessment. The level of evidence for the use of 
rituximab was determined for each off-label indication.
RESULTS: During the 6-month period, a total of 364 instances of off-label 
rituximab use was recorded in the national database. A total of 63 underlying 
diagnoses was identified. These were subclassified into haematological disorders 
(19%), autoimmune connective tissue diseases (12%), vasculitis (12%), 
neurological disorders (12%), transplant-related uses (12%), haematological 
malignancies (11%), muscle disorders (8%), renal diseases (6%), dermatological 
conditions (5%), other conditions (2%) and ocular diseases (1%). Forty percent 
of these requests were supported only by level 4 evidence of benefit. Data 
highlighted the non-standardised approaches to drug approval mechanisms, dosing 
schedules and monitoring for efficacy.
CONCLUSIONS: Off-label rituximab is prescribed for a diverse range of clinical 
conditions. Determining a safe and effective means of regulating this use within 
an evidence-based framework remains an ongoing challenge.