Autumn Meeting of the Irish Branch of the Association of Clinical Pathologists

Rituximab (Rituxan) is a genetically engineered chimeric murine/human monoclonal antibody and the first monoclonal antibody to become available to physicians for the treatment of malignant disease. It has recently been licensed for use in the treatment of patients with relapsed or refractory low-grade or follicular, CD20 positive B-cell Non-Hodgkins Lymphoma (NHL). Its mechanism of action is by binding to CD20 antigen on the B-lymphocytes and effecting cell lysis by possible complement activation and/or antibody-dependent cellular cytotoxicity. Several clinical trials have been able to show a moderate to limited response to Rituximab treatment in patients with relapsed follicular NHL with a 69% complete remission (CR) and up to 50% partial remission (PR).