Combination chemotherapy and rituximab

Rituximab is a human-mouse chimeric monoclonal antibody that has demonstrat ed efficacy against nonHodgkin's lymphoma (NHL). There is a powerful ration ale for combining rituximab treatment with chemotherapeutic agents that hav e also shown efficacy in NHL, since the mechanisms of action are distinct a nd there is also evidence that rituximab may sensitize chemoresistant tumor cells to the actions of cytotoxic drugs. A study of rituximab plus cycloph osphamide, doxorubicin, vincristine and prednisone (CHOP) chemoimmunotherap y has been carried out in 40 patients with low-grade NHL. In the 35 patient s who completed the study, the overall response rate was 100%, with 63% ach ieving a complete response, Median time to progression has not yet been rea ched at 47.2+ months. Molecular analysis (polymerase chain reaction) showed that CHOP plus rituximab (unlike CHOP alone) could completely clear blood and bone marrow of cells containing the bcl-2 gene translocation, a molecul ar marker of NHL cells. Rituximab can therefore add to the efficacy of CHOP without significantly increasing toxicity. A further study is underway to determine whether similar efficacy with less overall toxicity can be achiev ed using rituximab in combination with fludarabine, [(C) 2001 Lippincott Wi lliams & Wilkins.].