Single-Agent Ibrutinib Vs Standard of Care for Patients with Relapsed/Refractory (R/R) and Treatment-Naive (TN) Chronic Lymphocytic Leukemia (CLL): An Adjusted Comparison of RESONATETM and RESONATE-2TM with the French Lyon-Sud Database

Abstract

INTRODUCTION: The benefits of ibrutinib (ibr) have been demonstrated by the phase 3 RESONATE and RESONATE-2 trials for patients (pts) with R/R and TN (≥ 65 years) CLL, respectively. In these studies, ibr showed significantly improved progression-free survival (PFS) and overall survival (OS) vs approved comparators (ofatumumab [ofa] in RESONATE and chlorambucil [clb] in RESONATE-2). However, a number of other treatment regimens are widely used in clinical practice for CLL based on individual patient and disease characteristics; it is currently unknown if ibr results in better survival outcomes when compared directly with each of these other treatments. AIM: In the absence of a head-to-head comparison, we investigated the relative efficacy of ibr vs physician9s choice (PC) in pts with R/R or TN CLL by comparing pt-level data from RESONATE and RESONATE-2 with data from pts in a real-world setting (the Lyon-Sud database). This database holds electronic medical records for 390 pts with CLL from the academic Lyon-Sud Hospital in France; nearly all patients were diagnosed between 1990 and 2014. This is the first analysis of ibr vs PC in a real-world setting for pts with TN CLL. METHODS: Pt-level data from RESONATE (ibr, n = 195; ofa, n = 196) were compared with data on pts with CLL from Lyon-Sud who received 2nd(n = 107) or later-line treatment (3rd [n = 62], 4th [n = 43], and subsequent [n = 51] lines). Similarly, RESONATE-2 (ibr, n = 136; clb, n = 133) pt-level data were compared with those of pts aged ≥ 65 years who received 1st-line treatment (n = 131). In order to account for non-comparability due to lack of randomization, a multivariate Cox proportional hazards model was used to compare PFS and OS between treatments, including line of therapy, age, sex, disease stage (based on Binet/Rai), and deletion 17p or 11q mutations as covariates. For the definition of PFS, missing data for date of disease progression for pts in Lyon-Sud who initiated subsequent therapy were replaced by the conservative proxy of date of initiation of next treatment. Predicted PFS and OS curves for the Lyon-Sud cohort were derived from the multivariate model. RESULTS: For R/R pts in Lyon-Sud, across all treatment lines the most frequent regimens used were rituximab (R) + chemotherapy (n = 46), bendamustine + R (BR; n = 28), fludarabine + cyclophosphamide + R (FCR) (n = 27), clb + R (n = 19), R monotherapy (n = 21), and R-CHOP-based (n = 19); the remaining percentages comprised various other therapies, each used in CONCLUSIONS: Investigation of survival outcomes suggests that ibr administered to pts in RESONATE and RESONATE-2 was more effective than PC used in a real-world cohort of French pts with R/R or TN CLL, suggesting a 4.8-fold improvement in PFS and a 3.4-fold improvement in OS in R/R pts and 4-fold and 2.4-fold improvements in TN pts, respectively. These results further support the growing evidence that ibr significantly improves both PFS and OS vs commonly used regimens in the R/R and TN settings, and could have important implications for improving treatment of CLL in clinical practice. Disclosures Salles:Janssen: Consultancy, Honoraria; Gilead: Honoraria, Research Funding; Mundipharma: Honoraria; Amgen: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Roche/Genentech: Consultancy, Honoraria, Research Funding. Sarkozy:Sandoz: Research Funding; Janssen Research & Development: Honoraria; Gilead: Honoraria; Takeda: Research Funding. Ghesquieres:Mundipharma: Consultancy; Celgene: Consultancy, Membership on an entity9s Board of Directors or advisory committees; Roche France: Research Funding. Diels:Johnson & Johnson: Employment, Equity Ownership. Besson:Janssen: Employment. MacDougall:Janssen Research & Development: Research Funding; IMS Health: Employment. Hermans:Janssen Research & Development: Research Funding; IMS Health: Employment. Healy:Janssen Research & Development: Employment. Garside:Janssen Research & Development: Employment. Iraqi:Janssen Research & Development: Employment.