In vivo efficacy of IMGN529 in tumor xenograft models. (A) SCID mice (10 mice/group) bearing established SU-DHL-4 xenografts treated with a single intravenous administration on day 15 of PBS (○); 10 mg/kg of K7153A antibody (●); or IMGN529 at doses of 10 mg/kg (■), 5 mg/kg (□), or 2.5 mg/kg (△). (B) SCID mice (10 mice/group) bearing established DOHH-2 xenografts treated starting on day 12 with PBS (○), K7153A antibody (●) at 10 mg/kg × 1, IMGN529 (■) at 10 mg/kg × 1, rituximab (⋄) at 2 mg/kg, 2 qw × 3, or CVP (▽, cyclophosphamide 40 mg/kg × 1 intravenously, vincristine 0.5 mg/kg × 1 intravenously, and prednisone 0.2 mg/kg × 5 pdo). (C) SCID mice bearing established JVM-3 xenografts were treated as indicated starting on day 7 with PBS (○), K7153A antibody (●) at 5 mg/kg × 1), IMGN529 (▪) at 5 mg/kg × 1, ofatumumab (⋄) at 2 mg/kg, 2qw × 3, or bendamustine (▿) at 50 mg/kg. %T/C was calculated as the median tumor volume of each treated (T) group divided by the median tumor volume of the vehicle control (C) group, and activity was determined according to National Cancer Institute standards (%T/C ≤42% = active, %T/C value ≤12% = highly active).