Evaluation of in vivo therapeutic activity of rituximab and milatuzumab in the preclinical MCL model. SCID mice (in groups of 10) were injected intravenously with 40 × 10⁶ Jeko cells and observed daily for signs of tumor burden. The mAbs (trastuzumab 15 mg/kg, rituximab 15 mg/kg, milatuzumab 15 mg/kg, or the combination of rituximab and milatuzumab) were given every 3 days via intraperitoneal.injection, starting at day 15 after engraftment. The mean survival for rituximab- and milatuzumab-treated mice was 44.5 days (95% CI, 39%-51%), compared with 33.5 days for the milatuzumab-treated mice (95% CI, 28%-36%), and 38 days for the rituximab-treated mice (95% CI, 36%-42%).