Rituximab monotherapy improves time-to-next treatment (TTNT) compared with observation in patients with advanced stage follicular lymphoma (FL), according to an abstract presented at the 62nd American Society of Hematology (ASH) Annual Meeting and Exposition.
This study was presented by Sarah Perry, MD, MSc, BC Cancer Centre for Lymphoid Cancer, Vancouver, BC, Canada.
“Many patients with advanced stage FL present with low burden asymptomatic disease and are suitable for observation. Previous studies have shown that rituximab can delay the need for definitive therapy in these patients, and that rituximab maintenance does not offer a long-term advantage,” explained Dr Perry during her presentation.
Patients aged >16 years with newly diagnosed, advanced stage, asymptomatic, grades 1-3a FL, treated with rituximab monotherapy were identified using the BC Cancer Lymphoid Cancer and Provincial Pharmacy Database. Results were compared with 2 observation cohorts: patients who received observation before the availability of rituximab (observation 1) and patients who received observation since the availability of rituximab (observation 2).
The primary end point of the study was TNTT.
A total of 843 patients were identified and classified into 3 cohorts: rituximab monotherapy (n = 301), observation 1 (n = 302), observation 2 (n = 240). Median follow-up was longer for observation 1 (12 years) compared with rituximab monotherapy (4.5 years) and observation 2 (4.3 years).
The 3- and 5-year TNTT estimates were improved in the rituximab monotherapy cohort compared with the observation cohorts. The 3-year TTNT estimates for rituximab, observation 1, and observation 2 were: 73% (95% CI 67-79), 52% (47-58), 57% (51-65), respectively. The 5-year estimates were 61% (54-68), 40% (35-46), 44% (37-52), respectively (P < .001). Overall rate of transformation and OS were not significantly different between groups.
“While the overall rate of transformation and OS were not altered, patients receiving R-mono were approximately 50% less likely to require definitive therapy at 5-years, enabling some patients to avoid treatment toxicity and providing time for novel therapies to emerge,” concluded Dr Perry.—Lisa Kuhns
Perry SE, Lee DG, Freeman CL, et al. Rituximab Monotherapy Compared to Observation in Patients with Newly Diagnosed Asymptomatic Advanced Stage Follicular Lymphoma: A Retrospective Population-Based Analysis. Presented at: the 62nd ASH Annual Meeting and Exposition; Dec 5-8, 2020. Abstract 1122.
