Critical appraisal of the role of rituximab in the treatment of patients with previously untreated or treated chronic lymphocytic leukemia (CLL)

Patients with chronic lymphocytic leukemia (CLL) have benefited from the introduction of targeted therapy for leukemia. Rituximab (a chimeric murine-derived monoclonal antibody that targets CD20 on lymphocytes) was the first monoclonal antibody to affect the natural course of this disease. Several reports have shown modest single-agent activity in patients with CLL. However, the best results come from the combination of this agent with chemotherapy; a significant benefit has been seen with the use of fludarabine, cyclophosphamide, and rituximab (FCR). The addition of rituximab to chemotherapy boosted overall response rates, complete response rates and prolonged progression free survival. Recent data showed an overall survival benefit with FCR. Other combinations including bendamustine and rituximab appear more effective than bendamustine alone, while combining rituximab with other types of agents also appears to improve response rates. This type of relatively nontoxic regimen is being investigated in elderly patients who may not tolerate standard combination chemoimmunotherapies.