Prolonged progression-free survival and preserved quality of life in the Canadian prospective study of tositumomab and iodine¹³¹-tositumomab for previously treated, rituximab-exposed, indolent non-Hodgkin lymphoma

Abstract

Radioimmunotherapy offers a unique treatment modality for indolent non-Hodgkin lymphoma (iNHL). We report 5-year outcomes and quality of life (QoL) in tositumomab and iodine¹³¹-tositumomab (TST/I¹³¹-TST) treated patients with iNHL previously treated with rituximab. Ninety-three patients with ≥ 2 lines of therapy, responding to last treatment, were enrolled at 12 Canadian centers. Median age, disease duration and number of prior therapies (#PTx) were 59 years, 4.9 years and 5, respectively. Outcomes were response rate (43.0%), median progression-free survival (mPFS) (12.0 months), 5-year PFS (27%) and median overall survival (OS) (59.8 months). In responders, median response duration and mPFS were not reached. Improvements in QoL were seen by week 7. In univariate and multivariate analyses, hemoglobin, disease bulk and body surface area (BSA) predicted OS, whereas lactate dehydrogenase (LDH), bulk, BSA and #PTx predicted PFS. Most common adverse events (AEs) were fatigue and nausea. Two cases of myelodysplastic syndrome (MDS) were reported. TST/I¹³¹-TST was associated with durable responses, and prolonged OS and PFS in heavily pretreated iNHL.

Keywords::

• Indolent NHL
• radioimmunotherapy
• tositumomab
• durable response
• quality of life

Acknowledgements

The authors wish to thank the patients along with their families and the clinical investigators participating in this study. The authors thank Thomas Lin and Thierry Horner (Clinical Development, Oncology R&D, GlaxoSmithKline) for their editorial support and insightful comments, and Tina Haller (Statcon Consulting Services) for analysis and programming support. Special thanks are given to Lisa Toltl (post-doctoral fellow) for her assistance in preparing the preliminary draft of this manuscript.

This study was sponsored by GlaxoSmithKline, Mississauga, ON, Canada (Study Number SB-393229/032) and is registered at ClinicalTrials.gov: NCT00240565.

Potential conflict of interest

Disclosure forms provided by the authors are available with the full text of this article at www.informahealthcare.com/lal.