Zevalin® (ibritumomab tiuxetan): After more than a decade of treatment experience, what have we learned?

- Ibritumomab tiuxetan is a CD20-directed radiotherapeutic antibody.
- It has demonstrated therapeutic efficacy in treating non-Hodgkin's lymphoma.
- There is uncertainty among clinicians regarding its use.
- Since its approval, its treatment regimen has been simplified.
- Benefits include single agent efficacy and avoidance of many AEs of chemotherapy.

Non-Hodgkin's lymphoma (NHL) comprises a clinically and biologically heterogeneous group of lymphoproliferative disorders originating in B lymphocytes, T lymphocytes, or natural killer (NK) cells. The disease course may range from indolent to aggressive. Zevalin® (ibritumomab tiuxetan) is a radioactive drug product, which is the combination of a β-emitting isotope, 90Y, linked to the anti-CD20 monoclonal antibody (mAb), rituximab. It has demonstrated therapeutic efficacy with durable responses and allows delivery of ionizing radiation directly to the tumor site, while minimizing toxicity to normal tissue. Ibritumomab tiuxetan is indicated for treatment of patients with relapsed or refractory low-grade, follicular NHL, including patients who are refractory to rituximab, and as consolidation therapy in previously untreated follicular NHL in patients who achieve a partial or complete response to first-line chemotherapy. Despite the efficacy and acceptable safety profile of ibritumomab tiuxetan, utilization has not been broadly adopted in practice due to a number of factors. This manuscript will review the literature available for ibritumomab tiuxetan, including several new trials that are currently being studied, and discuss the rationale for use of ibritumomab tiuxetan in NHL.