Therapeutic efficacy of PRIT in athymic mice bearing Raji Burkitt lymphoma xenografts. PRIT mice were injected intravenously via the tail vein with 300 μg of either (A) anti-CD20 1F5-SA, (B) anti–HLA-DR Lym-1-SA, (C) anti-HD22 HD39-SA, (A-C) control HB8181-SA, or (D) a combination of the 1F5-SA and Lym-1-SA conjugates followed 20 hours later with 50 μg CA, and 4 hours later with 800 μCi (29.6 MBq) 90Y-DOTA-biotin. Untreated mice did not receive any therapy. Tumor growth was measured as described in the legend to Figure 1. Error bars represent SD.