Safety and Efficacy of Radioimmunotherapy with Yttrium 90 Ibritumomab Tiuxetan (Zevalin)

Patients with low-grade, follicular non-Hodgkin's lymphoma usually present with advanced disease, which is not considered curable with conventional therapies. New approaches are needed to improve the outcomes in patients with this disease. Yttrium 90 ibritumomab tiuxetan (Zevalin; Biogen Idec Inc, Cambridge, MA), is highly effective, with overall response rates of 73% to 83% and complete response rates of 15% to 51%, with a median duration of response in complete responders of 23 months. The response rates tend to be higher in patients who have been treated with fewer prior therapies, and ⁹⁰Y ibritumomab tiuxetan may be suitable for use early in the course of therapy. Delayed myelosuppression is the most common adverse effect, and it is predictable, reversible, and manageable. Yttrium 90 ibritumomab tiuxetan has less nonhematologic toxicity than chemotherapy, with only minimal alopecia, mucositis, nausea, or vomiting, and a lower incidence of infections. The ibritumomab tiuxetan regimen is routinely and safely given in an outpatient setting and is completed in 7 to 9 days, and is thus more convenient for patients than chemotherapy.