The effect of various immunosuppressive agents on mouse peritoneal macrophages and on the in vitro phagocytosis of Escherichia coli O4:K3:H5 and degradation of 125I-labelled HSA-antibody complexes by these cells.

Large doses of hydrocortisone, cyclophosphamide, and methotrexate injected subcutaneously, and whole-body irradiation (500 rads) caused a reduction in the number of peritoneal cells (PE cells) obtained after intraperitoneal injection of the treated mice with proteose-peptone. The same dose of cyclophosphamide and irradiation induced morphological changes in PE macrophages. There were more giant cells in the peritoneal exudates from treated mice as compared to control mice. 'Pharmacological' and larger doses of hydrocortisone, methotrexate and azathioprine or anti-lymphocyte globulin had no effect on the in vitro phagocytic capacity of proteose-peptone-stimulated mouse PE macrophages. This also applied to doses of up to 50 mg/kg of cyclophosphamide. In contrast, whole-body irradiation (500 rad) and 100 mg/kg of cyclophosphamide decreased the phagocytic capacity of mouse macrophages in vitro and reduced the ability of PE cells to degrade 125I-labelled HSA-antibody complexes in vitro. The greatest effect was noted 4-5 days after whole-body irradiation or four to five subcutaneous injections of cyclophosphamide

Safety and efficacy of ofatumumab, a fully human monoclonal anti-CD20 antibody, in patients with relapsed or refractory B-cell chronic lymphocytic leukemia: a phase 1-2 study

Safety and efficacy of the fully human anti-CD20 monoclonal antibody, ofatumumab, was analyzed in a multicenter dose-escalating study including 33 patients with relapsed or refractory chronic lymphocytic leukemia. Three cohorts of 3 (A), 3 (B), and 27 (C) patients received 4, once weekly, infusions of ofatumumab at the following doses: (A) one 100 mg and three 500 mg; (B) one 300 mg and three 1000 mg; (C) one 500 mg and three 2000 mg. Sixty-seven percent of the patients were Binet stage B, and the median number of previous treatments was 3. The maximum tolerated dose was not reached. The majority of related adverse events occurred at first infusion, and the number of adverse events decreased at each subsequent infusion. Seventeen (51%) of 33 patients experienced infections, 88% of them of grade 1-2. One event of interstitial pneumonia was fatal; all other cases resolved within one month. The response rate of cohort C was 50% (13/26), one patient having a nodular partial remission and 12 patients partial remission. In conclusion, ofatumumab was found to be well tolerated in patients with chronic lymphocytic leukemia (CLL) in doses up to 2000 mg. Preliminary data on safety and objective response are encouraging and support further studies on the role of ofatumumab in CLL patients. This trial was registered at www.clinicaltrials.gov as no. NCT0009331