Phase II trial of a transplantation regimen of yttrium-90 ibritumomab tiuxetan and high-dose chemotherapy in patients with non-Hodgkin's lymphoma

Purpose: This phase II trial evaluated the safety and efficacy of combining yttrium-90 (⁹⁰Y) ibritumomab tiuxetan with high-dose carmustine, cytarabine, etoposide, and melphalan (BEAM) and autologous stem-cell transplantation in patients with non-Hodgkin's lymphoma who were considered ineligible for total-body irradiation because of older age or prior radiotherapy. Patients and Methods: Between May 2002 and January 2006, 14 days before autologous stem-cell transplantation, 41 patients with non-Hodgkin's lymphoma received standard-dose ⁹⁰Y ibritumomab tiuxetan (14.8 MBq/kg [0.4 mCi/kg]) followed by high-dose BEAM. Results: The median age was 60 years (range, 19 to 78 years), and the median number of previous therapies was two (range, one to six). Disease histologies were diffuse large B-cell (n = 20), mantle cell (n = 13), follicular (n = 4), and transformed lymphoma (n = 4). With a median follow-up of 18.4 months (range, 5.5 to 53.3 months) the estimated 2-year overall and progression-free survival were 88.9% (95% CI, 75.3% to 95.2%) and 69.8% (95% CI, 56.4% to 79.7%). The median time to WBC engraftment was 11 days (range, 9 to 26 days) and time to platelet engraftment was 12 days (range, 3 to 107 days). Adverse events were similar to those seen historically with high-dose BEAM alone, and included grade 3 or 4 pulmonary toxicity in 10 patients. Conclusion: Adding ⁹⁰Y ibritumomab tiuxetan to high-dose BEAM with autologous stem-cell transplantation is feasible and has a toxicity and tolerability profile similar to that observed with BEAM alone. Rates of progression-free survival seen in these patients are promising and warrant additional study.