OBJECTIVES: To analyze the effectiveness of ibrutinib in patients with Chronic Lymphocytic Leukemia (CLL) in a tertiary hospital, in order to have real-life effectiveness data to confirm the high efficacy found in the pivotal RESONATE-2 trial.

METHODS: Single-center retrospective observational study of all CLL patients treated with ibrutinib from July/2016-June/2022. Variables collected: age, sex, mutations, Binet stage at baseline, B symptoms at baseline, baseline ECOG, line of treatment, starting dose/dose reduction, overall survival(OS), progression-free survival(PFS), and sustained improvement in hematological parameters in patients with cytopenias at baseline. The presence of high-risk cytogenetics was determined: 17p deletion, TP53 mutation, 11q deletion, immunoglobulin heavy chain mutational status(IGHV). The Kaplan-Meier method was used to calculate OS and PFS using SPSS®.

RESULTS: Forty-seven patients were included(68% men); mean age 69(±11) years.

19.2% patients had TP53 alteration, 59.5% unmutated IGHV, 8.5% 11q deletion, and 8.5% 17p deletion. The classification according to Binet staging was: A(42.6%), B(19.1%), C(21.3%) and not determined in 17%. 42.6% of patients had B symptoms at baseline.

51% patients had ECOG-1 at baseline and 40.4% ECOG-0.

65.9% patients initiated ibrutinib as first-line treatment.

All patients started with a dose of 420mg (4 patients had dose reduction due to toxicity).

Regarding effectiveness, the mean follow-up until progression was 55.8+/-3.8 months (17% of patients progressed), and the mean follow-up until death was 63.6+/-3.6 months (14.9% died). Median PFS was not reached while OS was 73 months(95%CI-NA-NA).

For patients with cytopenias at baseline(40.4%=thrombocytopenia, 42.5%=anemia, 12.8%=neutropenia), sustained improvement in hematological parameters was observed in 63.2% for platelets, 80% for hemoglobin and 100% for neutrophils.

CONCLUSIONS: Ibrutinib presents effectiveness data in CLL in line with those presented in RESONATE-2. The OS is highly influenced by the number of patients censored over 36 months. The improvement of the hematological parameters in patients who presented cytopenias at the beginning of treatment is high.