Impact of adherence to ibrutinib on clinical outcomes in real-world patients with chronic lymphocytic leukemia

Abstract

Ibrutinib is an oral Bruton’s tyrosine kinase inhibitor approved for treatment of chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL). Clinical trial data suggest that strict adherence is directly related to clinical outcomes. This retrospective, multicenter study aimed to evaluate ibrutinib adherence and its impact on clinical outcomes in patients with CLL/SLL treated in the real-world setting. The primary outcome was to quantify ibrutinib adherence rates in the real-world setting using the proportion of days covered (PDC) calculation. Secondary outcomes included the association of ibrutinib adherence with progression-free survival (PFS) and overall survival (OS). For the 100 patients in the primary analysis, the mean PDC was 95% (range: 65–100%). Patients who maintained PDC > 95% for each of the first 6 months experienced fewer PFS events (n = 1) compared to those with PDC ≤ 95% (n = 5; p=.03). The correlation between adherence and OS was not assessed due to a low number of events.

Keywords:

• Ibrutinib
• adherence
• real-world

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Disclosure statement

C.C.C. has served as a consultant for AbbVie, LOXO/Lilly, has received honoraria from AbbVie, AstraZeneca, Beigene, Genentech, LOXO/Lilly, MEI Pharma, Novartis, has served on the speaker’s bureau for AbbVie, and has received institutional funding for research from LOXO/Lilly and H3 Biomedicine. BM’s spouse is an employee and stockholder of Novartis Pharmaceuticals. A.R.M. receives research support from TG Therapeutics, Pharmacyclics, AbbVie, Adaptive Biotechnologies, Johnson and Johnson, Acerta/AstraZeneca, DTRM BioPharma, Sunesis, BeiGene, Genentech, Genmab, Janssen, Loxo Oncology, Nurix, and does advisory/consultancy/DSMB work with TG Therapeutics, Pharmacyclics, Adaptive Biotechnologies, AbbVie, Johnson and Johnson, Acerta/AstraZeneca, DTRM BioPharma, Sunesis, AstraZeneca, BeiGene, Genentech, Janssen, Loxo Oncology.