Rituximab maintenance therapy prolongs progression-free survival in patients with chronic lymphocytic leukemia (CLL) achieving at least a partial response to induction therapy with rituximab plus chemotherapy, a study published in The Lancet Haematology has shown.1
Induction therapy with rituximab plus chemotherapy improves outcomes compared with chemotherapy alone in many patients with CLL. Therefore, researchers sought to investigate the potential of rituximab maintenance therapy to prolong disease control in those who respond to rituximab-containing induction regimens.
For the international, open-label, phase 3 trial, investigators enrolled 263 patients who had achieved a complete response, a complete response with incomplete bone marrow recovery, or a partial response to first- or second-line rituximab containing chemoimmunotherapy. Participants were randomly assigned 1:1 to receive maintenance therapy with rituximab 375 mg/m2 IV every 3 months or observation for 2 years.
Results showed after a median observation time of 33.4 months for the rituximab group and 34.0 months for the observation group, median progression-free survival was significantly longer with rituximab (47.0 months vs 35.5 months; HR, 0.50; 95% CI, 0.33-0.75; P = .00077).
In terms of safety, researchers found that the incidence of grade 3 to 4 hematologic toxicities other than neutropenia was similar between the 2 treatment arms. A total of 21% of patients in the rituximab group and 11% of those in the observation arm experienced grade 3 to 4 neutropenia.
Further, the overall incidence of all grade infections was higher among patients who received rituximab compared with those in the observation arm (66% vs 50%).
“Although it is associated with an increase in infections, there is no excess in infection mortality, suggesting that remission maintenance with rituximab is an effective and safe option in the management of chronic lymphocytic leukemia in early treatment phases,” the authors concluded.
Greil R, Obrtlikova P, Smolej L, Kozak T, Steurer M, Andel J, Burgstaller S, et al. Rituximab maintenance versus observation alone in patients with chronic lymphocytic leukaemia who respond to first-line or second-line rituximab-containing chemoimmunotherapy: final results of the AGMT CLL-8a Mabtenance randomised trial [published online ahead of print June 15, 2016]. Lancet Haematol. doi: 10.1016/S2352-3026(16)30045-X.