Results with CTX followed by rituximab.

NOD/SCID mice that received transplants of 10 × 10⁶Namalwa cells intraperitoneally were given 3 courses of CTX (75 mg/kg) on days 3, 5, and 7 after transplantation and randomly assigned to receive 25 mg/kg of rituximab or PBS on days 15, 17, and 19 (first course) and on days 25, 27, and 29 (second course). Rituximab (⧫) delayed tumor growth in comparison with results in PBS-treated controls (▪) but did not prevent tumor growth or induce significant tumor regression after tumor regrowth. The dotted line indicates tumor growth in untreated controls (▴). Results are mean ± SD values for tumor volume (n = 4 per group).