Outcome of Patients with Relapsed/Refractory (R/R) Chronic Lymphocytic Leukemia (CLL) Treated with Ibrutinib within a Named Patient Program (NPP) in Italy. a Real-Life Retrospective Study

Introduction. Observational, real-life studies are relevant to understand whether data derived from prospective controlled trials (CTs) are reproducible in the day-to-day clinical practice. Within a named patient program (NPP), free and early access to ibrutinib was made available for the treatment of relapsed/refractory (R/R) patients with chronic lymphocytic leukemia (CLL) until this agent was approved in Italy. To define the efficacy and toxicity profile of patients treated with ibrutinib in this real-life setting, the GIMEMA (Gruppo Italiano Malattie EMatologiche dell'Adulto) group carried out a retrospective analysis on the outcome of R/R patients with CLL who received ibrutinib in the NPP. Methods. Between April 2014 and January 2015, 216 R/R patients with CLL managed at 20 centers in Italy were included in the NPP. Patients were required to have R/R disease with disease progression within 24 months after prior chemo-immunotherapy. All patients received ibrutinib at the standard dose of 420 mg daily, continuously until disease progression or unacceptable toxicity. The period of observation included the duration of the NPP and was extended up to January 2016 for patients still on treatment with the commercial drug. Clinical data were reported retrospectively by the treating physicians using the Research Electronic Data Capture (REDCap) system. Results. The median age of patients was 58.3 years (range 27.5-81); 89% of patients were in Binet stage B-C. The median number of prior treatments was 3 (range 1-14). Thirty-seven % of patients was refractory to prior treatment. Deletion 17p and/or TP53 mutations were found in 54% of patients and deletion 11q in 11.6%. Seventy-eight % of patients had an unmutated IGHV gene profile. Prior atrial fibrillation (AF) was reported in 13 cases (6%), while 7 patients with AF (3.3%) were on anti-arrythmic treatment. Hypertension was recorded in 76 cases (35.2%). The median follow-up of patients was 24 months (range, 1-24 months. A response to ibrutinib was observed in 172 patients (79.6%) with a clinical CR/CRi in 34 (15.7%) and a PR/PR-L in 138 (63.9%). Similar response rates were observed in patients with an unmutated IGHV gene status (82.1%) and in those with deletion 17p/TP53 mutations (79.6%). The progression-free survival (PFS) and overall survival (OS) at 24 months were 64.6% (95%CI: 58.0-71.9) and 72.7% (95%CI: 66.5-79.4), respectively. No differences in PFS and OS were observed according to the IGHV mutational status (IGHV unmutated vs mutated: PFS, 65.2% vs 61.0%; p=0.7; OS, 65.2% vs 72.0%, p=0.6) and the presence of TP53 aberrations (TP53 aberrations, present vs absent: PFS, 64.8% vs 64.1%; p=0.6; OS, 69.8% vs 72.7%; p=0.8). Forty-eight patients (22.2%) discontinued ibrutinib within 12 months and 22 (10.2%) within 12-24 months from the start of ibrutinib. Progressive disease and Richter syndrome were the most common reasons for discontinuation that accounted for 16.2% (35 patients) and 1.8% (4 patients) of cases, respectively, and occurred after a median of 17 months from the start of ibrutinib. Treatment discontinuations due to adverse events (AEs) were recorded in 25 patients (11.6%) after a median time of 6 months from the start of treatment and included infections/febrile events in 7 cases, bleeding events in 3 (intracranial hemorrhage 1), sudden death in 3, acute myocardial infarction in 1, ischemic stroke in 2, second malignancy in 3, diarrhea in 1. AF occurred during treatment in 14 (6.5%) patients and was the reason of ibrutinib discontinuation in 2. AEs leading to discontinuation was not specified in 3 cases. Other reasons for ibrutinib discontinuation in 6 (2.8%) patients were ASCT in 4, unplanned surgery in 1, unknown in 1. Survival probability at 12 months from treatment discontinuation due to AEs or DP/RS was 38.2 and 37.2 months respectively (p= 0.6). Conclusions. The results of this real-life study show that in unselected patients with R/R CLL the clinical activity of ibrutinib was comparable to that reported in CTs. However, a third of patients discontinued ibrutinib within 24 months from the start of treatment. An earlier introduction of ibrutinib in the treatment approach of R/R patients, a careful surveillance and management of toxicities will optimise the clinical benefits of ibrutinib in CLL patients treated in the clinical practice. Disclosures Mauro: Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Shire: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Zinzani:TG Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Astra Zeneca: Speakers Bureau; MSD: Honoraria, Speakers Bureau; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; PFIZER: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celltrion: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; SERVIER: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bayer: Membership on an entity's Board of Directors or advisory committees; PFIZER: Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Verastem: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; TG Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Bayer: Membership on an entity's Board of Directors or advisory committees. Cortelezzi:novartis: Consultancy; roche: Consultancy; abbvie: Consultancy; janssen: Consultancy. Carlo-Stella:AstraZeneca: Speakers Bureau; Bristol-Myers Squibb: Speakers Bureau; Janssen: Speakers Bureau; Sanofi: Consultancy; ADC Therapeutics: Research Funding, Speakers Bureau; Boehringher Ingelheim Italia: Consultancy; Genenta Science: Speakers Bureau; Rhizen Pharmaceuticals: Research Funding; Amgen: Speakers Bureau; MSD Italia: Speakers Bureau. Molica:Roche: Other: Advisory board; Gilead: Other: Advisory board; Jansen: Other: Advisory board; AbbVie: Other: Advisory board. Coscia:Janssen, Karyopharm: Research Funding; Abbvie, Gilead, Shire: Honoraria, Membership on an entity's Board of Directors or advisory committees. Zaja:Janssen: Honoraria; Novartis: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Amgen: Honoraria; Takeda: Honoraria; Sandoz: Honoraria; Abbvie: Honoraria. Gaidano:Roche: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Morphosys: Honoraria; AbbVie: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; Janssen: Consultancy, Honoraria. Gobbi:Ariad: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy; Amgen: Consultancy; Celgene: Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy; Pfister: Membership on an entity's Board of Directors or advisory committees. Cuneo:janssen: Other: advisory board, Speakers Bureau; Gilead: Other: advisory board, Speakers Bureau; Abbvie: Other: advisory board, Speakers Bureau; Roche: Other: advisory board, Speakers Bureau. Foà:JANSSEN: Other: ADVISORY BOARD, Speakers Bureau; NOVARTIS: Speakers Bureau; ROCHE: Other: ADVISORY BOARD, Speakers Bureau; ABBVIE: Other: ADVISORY BOARD, Speakers Bureau; AMGEN: Other: ADVISORY BOARD; CELTRION: Other: ADVISORY BOARD; GILEAD: Speakers Bureau; CELGENE: Other: ADVISORY BOARD, Speakers Bureau; INCYTE: Other: ADVISORY BOARD.