Severe infusion-related reactions are uncommon in rituximab-treated CLL patients in clinical practice: Results from a Swedish national observational study

• There have been concerns about infusion-related reactions with rituximab in CLL.
• We conducted an observational trial to study infusion-related adverse events.
• Severe events occurred in 5%, which in line with published randomized trials.
• Rituximab-containing CLL regimens can be considered safe in general practice.

There have been concerns about serious infusion-related adverse drug reactions (ADR) with rituximab in chronic lymphocytic leukemia (CLL). We therefore conducted an observational trial in which CLL patients planned for rituximab-containing therapy were eligible. Ninety-six patients from 19 centers were enrolled. The most common regimen was rituximab, fludarabine and cyclophosphamide. Fifty-six patients experienced ADR during rituximab infusion. Reactions ≥ grade 3 occurred in five patients and no cases of tumor lysis syndrome were recorded.Despite a high number of circulating tumor cells few severe ADR were noted. Thus, rituximab-containing regimens can be considered safe for CLL patients in general practice.