Rituximab is a monoclonal antibody that targets lymphoma cells by binding to a marker that is found on the surface of lymphoma cells. Rituximab has been widely used in Follicular (low grade) Non-Hodgkin Lymphoma. Current guidelines on treatment support its use both in previously untreated patients and those who have relapsed after treatment with chemotherapy. But how effective is Rituximab in these settings?
Rituximab can be given concurrently with chemotherapy, or after completion of chemotherapy. At least three major trials have shown that the chance of progression is approximately halved with the addition of Rituximab to chemotherapy. The time to progression is also nearly doubled with the addition of Rituximab (from 1.4 to 2.4 years in one study). Two recently reported trials have also reported an improvement in survival of about 6 and 13% at the end of 3 and 4 years respectively.
Rituximab is also endorsed for use in those who have had a relapse after a disease free period, or in those in whom the disease has not completely responded after treatment with chemotherapy. Many studies have been conducted in these settings. About half of the patients show response (that means at least a 50% reduction). About 10-15% have a complete response. And in those who respond, the disease stays controlled for an average of a year or more.
Rituximab is an exciting drug in the arsenal against follicular (low grade) lymphomas. All patients with follicular lymphomas may not require chemotherapy. However, in those who do,adding Rituximab to combination chemotherapy seems to improve results considerably. Rituximab also seems to be highly effective in the setting of relapsed or refractory disease. It may not benefit all patients, but it does reduce disease in many, and can keep the disease from progressing for a year or more.
