Real-world outcomes for 205 patients with chronic lymphocytic leukemia treated with ibrutinib

Ibrutinib has now been approved for treatment of chronic lymphocytic leukemia (CLL) in both front-line setting and as later-line treatment. However, knowledge about the outcomes and adverse events (AE) among patients at a population-based level is still limited. Objectives: To report outcomes and AEs in a population-based cohort treated with ibrutinib outside clinical trials. Methods: We conducted a multicenter, retrospective cohort study including all patients with CLL treated with ibrutinib. Results: In total, 205 patients were included of whom 39 (19%) were treatment-naïve. The median follow-up was 21.4 months (interquartile range (IQR), 11.9,32.8), the estimated overall survival at 12 months was 88.8% (95% confidence interval (CI); 84.3%, 93.3%), and the estimated progression-free survival at 12 months was 86.3% (95% CI; 81.3%, 91.2%). During follow-up, 200 (97.6%) patients had at least one AE and 100 (48.8%) patients had at least one grade ≥3 AE. Eighty-six patients (42.0%) discontinued ibrutinib, hereof 47 (54.7%) due to AEs and 19 (22.1%) had progression of CLL or Richter transformation. Conclusions: In our study, we find comparable, though slightly inferior, overall, and progression-free survival, and discontinuation due to toxicity was higher compared with clinical trials. Patient training and information may improve treatment adherence outside clinical trials.