Yttrium-90 ibritumomab tiuxetan (Zevalin) for patients with aggressive non-Hodgkin`s lymphoma unsuitable for systemic chemotherapy

Abstract

Background:Yttrium-90 (90Y) ibritumomab tiuxetan (Zevalin�) is a radioimmunoconjugate targeting the CD20 antigen and it has been approved for the treatment of relapsed or refractory low-grade lymphoma. However, its efficacy for aggressive B-cell non-Hodgkin`s lymphoma(NHL) has not been determined. We tried 90Y-ibritumomab tiuxetan monotherapy for patients with CD20+ aggressive NHL who were unsuitable for systemic chemotherapy. Methods: Seven patients were included who were diagnosed as diffuse large B-cell lymphoma(DLBL) or mantle cell lymphoma (MCL) without bone marrow involvement. These patients could not receive complete cycles of first-line chemotherapy due to unfavorable host factors; age≥75 or chronic medical illness with organ dysfunction. 90Y-ibritumomab tiuxetan was delivered as a substitute for systemic chemotherapy. A rituximab (250 mg/m2) pretreatment was infused intravenously on Days 1 and 8, to reduce the nonmalignant CD20 binding. 90Y-ibritumomab tiuxetan (0.3 mCi/kg) was administered within 4 hours after the second rituximab infusion on Day 8 via slow intravenous push. Results: Four of seven patients achieved an objective response including two complete response(CR) with CR duration of 19.0 months and 15.3 months, respectively. All patients were well tolerable except one patient who died from neutropenic sepsis on day 39. Five patients experienced grade 3 or 4 thrombocytopenia between day 27 and day 32. Grade 3 or 4 neutropenias were observed in five patients between day 28 and day 37 after treatment. Conclusion: 90Y-ibritumomab tiuxetan seems to be a promising agent for the patients with aggressive NHL who are unable to tolerate systemic chemotherapy.