Monoclonal Antibody I F5 (Anti-CD2O) Serotherapy of Human B Cell Lymphomas

Four patients with refractory malignant B cell lymphomas were treated with continuous intravenous (IV) infusions of murine monoclonal antibody (MoAb) 1 F5 (anti-CD2O) over five to ten days. Dose-dependent levels of free serum 1 F5 were detected in all patients. Two patients had circulating tumor cells and in both cases 90% of malignant cells were eliminated from the blood stream within four hours of initiation of serotherapy. Antigenic modulation did not occur. and sustained reduction of circulating tumor cells was observed throughout the duration of the infusions. Serial bone marrow aspirations and lymph node biopsies were examined by immunoperoxidase and immunofluorescence techniques to ascertain MoAb penetration into extravascular sites. High doses (100 to 800 mg/m2/d and high serum 1F5 levels (13 to 190 g/mL) were required to