[Rituximab]

CHOP has been the standard chemotherapy for aggressive non-Hodgkin's lymphoma (NHL). However, indolent NHL remains largely an incurable diseases, with nearly static overall survival, and only 40% of patients with aggressive NHL are cured by CHOP. Monoclonal antibodies are an exciting advance in the treatment of lymphoma. Rituximab is a mouse/human chimeric monoclonal antibody that targets the CD20 antigen found on the surface of malignant and normal cells of the B-cell lineage, but not on primitive stem cells or mature plasma cells. Rituximab is safe and well-tolerated, and exhibit little cross-resistance with conventional chemotherapeutic agents. Clinical trials with rituximab indicate that the drug has broad application to NHL, although further clarification is needed to determine its optimal use in many of these clinical settings. In indolent NHL, rituximab has shown useful response rates, both as first-line therapy in relapsed disease. In aggressive lymphomas, diffuse large B-cell lymphoma is the most common form, the addition of rituximab to CHOP chemotherapy significantly lengthens disease-free and overall survival compared to CHOP alone as first line therapy, at least in elderly patients. These included combination with chemotherapy, prolonged or increased dosing regimens, and maintenance therapy, in which rituximab is administered to patients in remission to eliminate minimal residual disease and reduce the risk of relapse. Rituximab in vivo purging and maintenance is also being evaluated in autologous transplantation setting. Newer agents, including radiolabelled antibodies, Immunotoxin-linked antibodies and antibodies against novel target antigens are being tested in on-going clinical trial.