Radioiummunotherapy after chemotherapy found safe and effective for follicular non-hodgkin lymphoma patients

Radioimmunotherapy with the radioactive drug yttrium-90 (90Y) ibritumombab tiuxetan, following chemotherapy with fludarabine and mitoxantrone, is feasible, well tolerated, and effective in patients with follicular non-Hodgkin lymphoma (NHL). These are the conclusions of authors of an Article published early online and in the April Edition of The Lancet Oncology.

Follicular lymphoma accounts for around 30% of all newly diagnosed NHLs, and is the most common form of lymphoma in the USA and Europe. The findings of various trials have shown that combination of a chemotherapy regimen with rituximab (a non-radioactive targeted treatment for B-cell lymphomas) significantly increased progression-free-survival compared with the same chemotherapy regimen alone.

The researchers wanted to see if these benefits could be improved if, instead of rituximab, 90Y-ibritumombab tiuxetan was used-which, as with rituximab, is able to target B-cell lymphomas by attaching to a surface protein on those cells. Once attached, β-radiation from the radioactive yttrium-90 attacks and kills these highly-radiation sensitive lymphoma cells.

Professor Pier Luigi Zinzani, at the Institute of Haematology and Oncology 'L & A Seràgnoli', University of Bologna, Italy, and colleagues did a study of 61 patients across 13 Italian institutions. All received six cycles of oral fludarabine and intravenous mitoxantrone; and 57 of these-43 with complete response (CR) and 14 with partial response (PR)-were deemed eligible for subsequent 90Y-ibritumombab tiuxetan. Then of the 14 PR patients, 12 achieved CR after 90Y-ibritumombab tiuxetan treatment; thus overall 55 of the 57 patients achieved complete response after the combined treatment regimen.

Further, with a median follow-up of 30 months, 3-year progression-free survival was estimated at 76%, and 3-year overall survival 100%. 36 of 57 patients had grade 3 or 4 haemotological toxic effects.

The authors conclude: "This study has established the feasibility, tolerability, and efficacy of sequential treatment with six cycles of fludarabine and mitoxantrone chemotherapy followed by 90Y-ibritumombab tiuxetan as a front-line treatment for untreated patients with follicular NHL. In particular, the data represent the first evidence of a role of 90Y-ibritumombab tiuxetan after a fludarabine-containing regimen in the treatment of follicular NHL."