Incidence of Neutropenia With Venetoclax and Obinutuzumab in CLL
Posted: Tuesday, August 17, 2021
An increased incidence of grade 3 or 4 neutropenia was reported in patients with chronic lymphocytic leukemia (CLL) who were treated with the BCL2 inhibitor venetoclax and the monoclonal antibody obinutuzumab compared with previous reports, according to a retrospective study published in Cancer Reports. Manali Kamdar, MD, of the Blood Disorders Center at the University of Colorado, Aurora, and colleagues indicated that real-world data regarding neutropenia with this treatment combination is sparse. “Our study cohort had higher rates of comorbidities, high-risk features, concomitant interacting medications, and prior chemotherapy” compared with clinical trials, explained the authors.
In this single-center study, 19 patients with CLL were treated at the University of Colorado Hospital with venetoclax and obinutuzumab. In all, 73% of patients developed grade 3 or 4 neutropenia during therapy—66% of treatment-naive patients and 86% of patients with relapsed or refractory disease—a significantly higher rate of neutropenia than previously reported (52.8% vs. 58%).
High-risk disease features and comorbidities were higher in this patient cohort than in previous studies, such as del17p mutation (26.3%), unmutated IGHV (89.5%), and TP53 mutation (26.3%). The rate of comorbidities was also increased; 94.7% of patients had a cumulative illness rating scale score of 6 or greater. Additionally, 36.8% of the patient cohort had received at least one prior line of therapy.
One-third of patients were unable to tolerate the approved venetoclax dose of 400 mg. However, five of six patients who received growth factor support were able to complete the venetoclax dose escalation. “Further studies are warranted to determine if proactive growth factor support is efficacious to maximize therapy duration,” the authors concluded.
Disclosure: For full disclosures of the study authors, visit onlinelibrary.wiley.com.