Use of Ibrutinib for Chronic Lymphocytic Leukemia (CLL) in Routine Clinical Practice: Results from the Belgian Ibrutinib Real-World Data (BiRD) Study

Objectives: To assess ibrutinib use for treatment of CLL based on real-world data in Belgium.Methods: BiRD is a multicenter, observational study. This interim analysis assessed demographic and disease-related data of patients with a confirmed diagnosis of CLL who were eligible for ibrutinib reimbursement at treatment start, or participated in a Medical Need Program (MNP) and switched to reimbursed ibrutinib treatment.Results: 140 patients with CLL were included in this analysis. Median age at ibrutinib initiation was 71 (range, 38-90) years; 87 (62.1%) patients were male. Median time between diagnosis and ibrutinib initiation was 6.3 years. Fourteen (10.0%) patients received ibrutinib first-line (all had del17p or TP53 mutation), 41 (29.3%) second-line, 49 (35.0%) third-line; 36 (25.7%) patients had >3 previous lines. Among patients with prior lines (n=126), most widely used regimens just preceding ibrutinib initiation were fludarabine+cyclophosphamide+rituximab (n=42; 33.3%) and bendamustine+rituximab (n=18; 14.3%).Table shows genetic status. Patients without documented del17p and/or TP53 mutation (n=33) were older (median 75.0 vs 70.0 years), more likely to have had u22652 prior lines of therapy (69.7% vs 36.7%) and had a longer time from diagnosis to ibrutinib initiation (8.9 vs 4.3 years) than patients with documented del17p and/or TP53 mutation (n=49). A higher proportion of patients who entered through the MNP had u22652 prior lines than those who did not (77.8% vs 54.8%). Of 140 patients, 23 (16.4%) started ibrutinib while on any antithrombotic therapy; 22/134 (16.4%) had a history of cardiovascular disease. Creatinine clearance was <30 mL/min in 3/130 (2.3%) patients, and u226530-<70 mL/min in 41/130 (31.5%). Ibrutinib dose at initiation was lower (140-280 mg) than recommended (420 mg) in 17/140 (12.1%) patients.Conclusion: BiRD provides information on real-world ibrutinib use, including initiation at recommended dose, cytogenetics and other characteristics of CLL patients in Belgium.