Rituximab Maintenance Prolongs PFS in Patients with Relapsed Lymphoma
The majority of patients with follicular lymphoma will relapse after initial response to therapy. A high-dose chemotherapy and autologous stem-cell transplantation (HDC-ASCT) strategy has been shown to improve outcomes in patients with recurrent disease. The benefit of rituximab (Rituxan) maintenance has been shown in patients with relapsed follicular lymphoma in the first-line and salvage settings but not in the setting of second-line maintenance after HDC-ASCT. The first randomized study has now investigated the role of rituximab as a purging agent before collecting the stem-cell product and as post-ASCT maintenance therapy (Pettengell R, et al. J Clin Oncol. 2013;31:1624-1630).
Between October 1999 and April 2006, 280 patients with relapsed follicular lymphoma who achieved complete remission (CR) or very good partial remission (VGPR) were enrolled in the European Group for Blood and Marrow Transplantation Lymphoma 1 trial. (The trial was stopped early because of slow recruitment.) Patients were randomized in a 2 × 2 factorial design to rituximab purging versus no rituximab purging, and to rituximab maintenance versus no rituximab maintenance. The randomization was stratified by CR versus VGPR and by number of remissions. The primary end point was progression-free survival (PFS).
After reinduction chemotherapy, 30% of the patients had a CR and 70% had a VGPR. In vivo purging with rituximab had no effect on PFS at 10 years. By contrast, rituximab maintenance had a significant impact on PFS: at 10 years, the PFS rate for rituximab maintenance was 54% versus only 37% without rituximab maintenance. No impact on overall survival (OS) was seen in any of the groups. This study shows for the first time the benefit and safety of rituximab maintenance for up to 8 months after HDC-ASCT in prolonging patients’ PFS.