Anti–CD20-mIFNα treatment can eradicate established, rituximab-insensitive human CD20⁺ B-cell lymphoma. (A) Early treatment model. Mice (n = 4 per group) were treated with the indicated doses of fusion protein or saline (HBSS) 1, 2, and 3 days after tumor inoculation (arrows). *P = .01. (B) Late treatment model. Mice (n = 8 per group) were treated with 10 μg of fusion protein or equivalent molar concentration of the indicated proteins 5, 6, and 7 days after tumor inoculation (arrows). Mice in the repeat dosing group were given 2 additional 30-μg doses of fusion protein 12 and 19 days after tumor inoculation (thick arrows). *P = .001. **P = .007. The data from 3 independent experiments, each of which included HBSS and fusion protein groups, were combined.