Bendamustine and Rituximab for the Treatment of Chronic Lymphocytic Leukemia: The Moffitt Cancer Center Experience
Authors: Pound Heather Barnes , Ho Viet Q. , Bello Celeste M. , Cultrera Jennifer L. , Extermann Martine , Lancet Jeffrey E. , Sotomayor Eduardo M. , Pinilla-Ibarz Javier 
Published: October 2019

Abstract
Abstract 4620

Introduction:
Although bendamustine is approved for the treatment of chronic lymphocytic leukemia (CLL), the combination of bendamustine and rituximab (BR) is currently under active investigation in the relapsed/refractory setting as well as for front-line use. Emerging data now suggests BR is acceptable for first-line use and indeed is listed in the NCCN Compendia as a first-line option. Herein, we report the results of a single-center retrospective review of BR use in first-, second- and third-line and beyond and its effects on response rate.

Methods:
We retrospectively reviewed 21 consecutive patients with CLL that received BR at the Moffitt Cancer Center (MCC) between July 2008 and November 2010. Bendamustine was dosed at 70 mg/m2 IV on Days 1 and 2 every 3–4 weeks; rituximab was dosed at 375 mg/m2 IV once with each cycle along with anti-microbial prophylaxis. Data collected included, but was not limited to age, gender, cytogenetic profile, number of previous therapies, Rai stage at time of treatment and response (based on 1996 NCI-WG definition). The primary objective was to assess response rates. The major secondary objective was to assess the effect of cytogenetics on response rates. All analyses were performed using descriptive statistics.

Results:
Twenty-one patients received treatment with BR; 7 patients received BR as first-line therapy, 7 received BR as second line therapy and the remaining 7 received BR as third-line therapy or beyond. The median age at time of treatment was 66; 12 of 21 patients were male (57%); All Rai Stages were represented, Stage 0 (n=1), Stage 1 (n=4), Stage 2 (n= 3), Stage 3 (n=5), Stage 4 (n=6). 38% of patients were positive for Del11q, 33% for Del13q, 9.5% for Del17p, and 9.5% for mutated IgVH. In previously untreated patients, 6/7 had a documented complete remission (CR) (71.4%) or partial (PR) (14.3%) response; one patient progressed (PD) on therapy. In second-line therapy, all patients had a documented CR (28.6%) or PR (71.4%). In patients treated with BR as 3rd or 4th line therapy, 3 patients had a CR, 2 patients had stable disease (SD), and 2 had PD. Of the 8 patients with Del11q, 37.5% achieved a CR, 4 had PR and 1 had PD. Of the 7 patients with Del13q, 4 achieved CR and 3 had a PR. Both patients with Del17p had PD. Of the 2 patients with mutated IgVH, one patient achieved a PR while the other had PD.

Conclusion:
Based on these results, the combination of bendamustine and rituximab in patients with CLL is efficacious and well tolerated in patients with both newly diagnosed and relapsed/refractory disease.

Disclosures:
Off Label Use: Bendamustine and rituximab for CLL. Ho:Genentech: Honoraria; Cephalon: Consultancy. Cultrera:Genentech: Speakers Bureau. Sotomayor:Genentech: Membership on an entity’s Board of Directors or advisory committees. Pinilla-Ibarz:Genentech: Speakers Bureau; Cephalon: Speakers Bureau.