The iodine I-131 tositumomab therapeutic regimen: Summary of safety in 995 patients with relapsed/refractory low grade (LG) and transformed LG non-Hodgkin's lymphoma (NHL)

6732 Background: The Bexxar (tositumomab and iodine I 131 tositumomab [B]) therapeutic regimen yields high rates of complete and durable responses in pts with relapsed/refractory LG NHL. Methods: The safety of B therapy was reviewed for 995 pts with relapsed/refractory LG NHL, including 230 pts in 5 clinical trials and 765 pts in an expanded access program (EAP). Demographics and risk factors were similar for both groups except that pts from EAP were less heavily pretreated (median, 2 vs 4 prior therapies) and more frequently received Rituximab (56% vs 17%). All adverse events (AEs) occurring within 13 wks of treatment were reported, regardless of relationship to study drug. Median follow-up was 24 mo (range, 0.1 - 118 mo). Results: Most frequent hematologic (heme) AEs were grade (gr) 3/4 neutropenia (41%), thrombocytopenia (37%), and anemia (12%), requiring supportive care in 27% of pts (G-CSF, 12%; erythropoietin, 10%; platelet transfusions 12%; packed RBCs, 16%). Bleeding events occurred in 7% of pts (...