Efficacy and safety of monoclonal anti-CD20 antibody (rituximab) for the treatment of patients with recurrent low-grade non-Hodgkin's lymphoma after high-dose chemotherapy and autologous hematopoietic cell transplantation.

The major cause of treatment failure following high-dose therapy with autologous hematopoietic cell transplantation (AHCT) for low-grade lymphomas (non-Hodgkin's lymphoma [NHL]) is persistent disease or recurrence. Most patients whose disease progresses following AHCT have resistant disease and limited bone marrow reserve. In this setting, treatment options are limited and responses to conventional chemotherapy are generally poor. Rituximab is a chimeric immunoglobulin G1 kappa monoclonal antibody that recognizes the CD20 antigen on B-cells. Published data on the use of rituximab for the treatment of recurrent NHL after autologous transplantation are limited. We present a detailed report of anti-CD20 antibody treatment for 8 patients with recurrent follicular low-grade NHL after high-dose therapy and autologous transplantation. Rituximab was administered at 375 mg/m2 intravenously once weekly for a total of 4 infusions. Median follow-up for this study was 23.4 months. Six (75%) of 8 patients responded to rituximab (2 complete response, 4 partial response). The Kaplan-Meier estimated median time to progression was 17.8 months. Rituximab was generally well tolerated. One patient developed delayed neutropenia. Other side effects were infusion related and transient. Two patients were re-treated with rituximab for progressive disease and achieved partial response. In summary, this retrospective study suggests that anti-CD20 antibody treatment is feasible in the treatment of patients who relapse or progress with low-grade NHL after autologous transplantation. There appears to be a high proportion of patients who benefit and have durable responses. Anti-CD20 antibody should be considered as a first-line salvage treatment for patients with CD20+ recurrent low-grade NBL in whom high-dose therapy has failed.