Rituximab Utilization Evaluation with Focused on Available Evidence for Off-Labeled Indications

Abstract

Background: To investigate the on-labeled and off-labeled indications of rituximab according to available evidence and the cost benefit of using this expensive drug.

Methods: This retrospective cross-sectional study was conducted between August 2016 and August 2017 at a teaching hospital affiliated to Iran University of Medical Sciences, Tehran, Iran. Patients’ demographic data and disease, indication for rituximab use, its dosage and treatment regimen and previous and concurrent treatments was assessed. The collected data were compared with the current criteria for the pattern of rituximab use. The last version of Lexicomp® acquired by Wolters Kluwer was used as the reference for on-labeled and off-labeled indications of the prescribed drug and its dosage. Level of evidences for applied indications and cost has also been evaluated.

Results: A total of 85 patients received rituximab during the study period. The most frequent reasons for rituximab prescription were: multiple sclerosis (50.58%), systemic sclerosis (10.58%), rheumatoid arthritis (7.05%) and Idiopathic inflammatory myopathies (4.70%).Rituximab was used in 8 (9.4%) cases according to on-labeled indications. There was level C evidence for rituximab use in off-labeled indications in 47 (55.29%) cases according to available evidences which accounts for the highest calculated cost.

Conclusion:Based on our results, rituximab was frequently administrated for off-labeled indications most of which are not supported by established levels of evidence. The total cost was higher for level C evidence indications of off labeled rituximab than for indications with a higher level of evidence (A and B). So, strong evidence is necessary for decision making regarding its effectiveness and its cost benefit.

J Pharm Care 2019; 7(1-2): 14-20.