Phase II study of ⁹⁰Y Ibritumomab tiuxetan (Zevalin) in patients with previously untreated marginal zone lymphoma

Abstract

The best upfront therapy for patients with non-gastric extranodal marginal zone lymphomas (MZLs) is not defined. We assessed the safety and efficacy of radioimmunotherapy with ⁹⁰yttrium (⁹⁰Y) ibritumomab tiuxetan as upfront therapy in MZL (NCT00453102). A total of 16 patients were enrolled, 81% with advanced-stage disease and 44% with bulky disease. The overall response rate (ORR) at 12 weeks post-therapy was 87.5% (90% confidence interval [CI]: 65.6–97.7%), including a complete response in eight (50%), complete response unconfirmed in one (6%) and partial response in five (31%) patients. With a median follow-up of 65.6 months (range 4.0–96.5), the median progression-free survival (PFS) was 47.6 months (range 4.0–93.3) and median overall survival (OS) was not reached. The 5-year PFS was 40% (90% CI: 19.9–59.5%) and 5-year OS was 71.8% (90% CI: 46.8–86.5%). Overall, ⁹⁰Y ibritumomab tiuxetan was well tolerated and led to long-term responses and PFS rates.

Keywords::

• Marginal zone lymphoma
• radioimmunotherapy
• ⁹⁰Y ibritumomab tiuxetan

Acknowledgements

I.S.L. is supported by National Institutes of Health (NIH) grant NIH CA109335, the Lymphoma Research Foundation and the Dwoskin Family, Recio Family and Anthony Rizzo Family Foundations. We thank all patients who participated in this study, and the University of Miami Miller School of Medicine and Sylvester Comprehensive Cancer Center for their research support.

Potential conflict of interest

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