Abstract: 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.

Abstract: Hairy cell leukemia (HCL) is a rare lymphoproliferative disease with an excellent prognosis after treatment with cladribine (2CDA), although relapse may occur during follow-up. The aim of the study is to review the efficacy, safety, long-term remission rate, and overall survival (OS) in those patients who received 2CDA as first-line treatment. We retrospectively reviewed data of HCL patients treated with 2CDA between March 1991 and May 2019 at 18 Italian Hematological centers: 513 patients were evaluable for study purpose. The median age was 54 years (range 24–88) and ECOG was 0 in 84.9% of cases. A total of 330 (64.3%) patients received 2CDA intravenously and 183 (35.7%) subcutaneously. ORR was 91.8%: CR was obtained in 335 patients (65.3%), PR in 96 (18.7%), and hematological response in 40 (7.8%) patients; in 42 (8.2%) no response was observed. Hemoglobin value ( p  = 0.044), frequency of circulating hairy cells ( p  = 0.039), recovery of absolute neutrophil count ( p  = 0.006), and normalization of spleen ( p  ≤ 0.001) were associated with CR compared to PR in univariable analysis. At a median follow-up of 6.83 years (range 0.04–28.52), the median time to relapse was 12.2 years. A significant difference in duration of response was identified between patients that obtained a CR and PR (19.4 years versus 4.8 years, p   〈  0.0001). Non-hematological grade 3 or higher early toxicity was reported in 103 (20.1%) patients. Median OS was not reached: 95.3%, 92.4%, and 81.8% of patients were estimated to be alive at 5, 10, and 15 years, respectively. Forty-nine patients died (9.5%), following an infection in 14 cases (2.7%), natural causes in 14 (2.7%), cardiovascular events in 13 (2.5%), a second neoplasm in 6 (1.2%), and progression of HCL in 2 cases (0.4%). Following treatment of HCL with 2CDA, 80% of patients are estimated to be alive 15 years after diagnosis.

Abstract: Hairy cell leukemia (HCL) is a rare lymphoproliferative disease with specific morphologic and molecular features and excellent prognosis. Although high rate of complete response (CR) has been reported after treatment with purine analogs, expecially cladribine (2CDA), relapse may occur during follow-up. The aim of the study is to review the efficacy, safety, long term remission rate and overall survival (OS) in those patients (pts) that received 2CDA as first line treatment. We retrospectively reviewed data of all HCL pts treated with 2CDA between March 1991 and May 2019 at 18 Italian Hematological centers. Among 553 pts reported, only 513 were evaluable because treated with 2CDA alone. Considering the clinical carachteristics, M/F ratio was 4.5 with a median age of 54 years (range 24-88) and ECOG 0 in 85% of cases. Splenomegaly and presence of circulating hairy cells recorded by morphology were reported in 241 (47%) and 138 (27%) pts, respectively. Thirty-seven (7%) pts presented with an infection. Other comorbidities were cardiovascular in 29 (6%) pts, a previous cancer or diabetes in 27 (5%) each, chronic hepatic disorders in 18 (3%), obstructive pulmonary disease in 16 (3%), chronic kidney disease in 3 (1%). Three hundred-thirty (64%) pts received 2CDA intravenously (253 as daily continuous infusion for 5-7 consecutive days and 77 as weekly infusion for 5-7 consecutive weeks) and 183 (36%) subcutaneously. Response criteria were defined as per recent consensus guidelines (Grever MR et al. Blood 2017). The overall response rate (ORR) was 83%: CR in 335 pts (65%) and partial response (PR) in 96 (19%); 40 (8%) pts obtained hematological improvement (HI) and in 42 (8%) no response was observed. Nine of 11 (82%) pts with HI and 18/25 (72%) non responders who received salvage therapy obtained a major response (fig. 1). A slightly higher hemoglobin value (12.4 vs 11.4 g/dl, p=0.044), a reduced frequency of circulating hairy cells (28.7% vs 31.8%, p=0.039), absence of palpable splenomegaly (p= & lt;0.001) and a faster recovery of ANC (28 days vs 41 days, p= 0.006) were associated with CR compared to PR in univariable analysis. No differences in terms of quality and duration of response, infection rate and time to blood counts recovery were reported according to the 2 routes of administration. Among pts receiving intravenous 2CDA, ORR was 85% for continuous infusion and 78% for weekly infusion: no statistically significant difference could be observed. Median duration of response was 12.2 years: 75.1%, 53.6% and 45.5% of responding pts are expected to be free from relapse at 5, 10 and 15 years, respectively. A statistically significant difference in duration of response was identified between pts that obtained a CR compared to pts in PR (19.4 years versus 4.7 years, p & lt;0.0001) (fig. 2). No other differences in relapse free survival (RFS) were identified. Non-hematological grade-3 or higher early toxicity was reported in 108 (21%) pts, due to infections in 102 cases (20%), mainly fever of unknown origin and pneumonia. In 6 cases infection due to invasive aspergillosis, bacteric pneumonia and bacteric sepsis caused the death of pts. Other non-hematological adverse events were almost all grade-1 allergy (47 pts, 9%). No late toxicity was reported, but 19 (4%) second cancers were observed. Among 118 pts relapsed after a median of 4.4 years (fig. 1), 85 (72%) were retreated with 2CDA, alone (65 cases) or associated with rituximab (20 cases); 11 (9%) with pentostatin, alone (7 cases) or associated with rituximab (4 cases), 8 (7%) with interferon α, 8 (7%) with rituximab alone, 1 (1%) with vemurafenib and zanubrutinib each; 2 were lost at follow-up and 2 died before retreatment. Overall, 58 (51%) retreated pts obtained a CR (42 after 2CDA), 37 (32%) a PR (32 after 2CDA), 7 (6%) a HI (4 after 2CDA) and 12 (11%) did not show any response (6 after 2CDA). Median OS was not reached; 95.7%, 92.8% and 82.3% of pts are expected to be alive at 5, 10 and 15 years, respectively (fig. 2). Overall 51 pts died (10%), during the induction phase in 6 cases and during follow-up in 45: overall, mortality was HCL-related in 14 patients (2 progression of disease and 12 infections) and HCL-unrelated in 37 patients (cardiovascular events in 16, natural causes in 15, a second cancer in 6). 2CDA is greatly effective in treating HCL, with an ORR of 83%. Early and long term adverse events were rare and easily managed: although HCL-related mortality is still possible, OS at 15 years is higher than 80% Disclosures Motta: Roche: Honoraria; Janssen: Honoraria. Offidani:Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; BMS: Consultancy, Honoraria. Tedeschi:Abbvie: Honoraria, Speakers Bureau; Sunesis: Honoraria, Speakers Bureau; Acerta: Honoraria, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Beigene: Honoraria, Speakers Bureau. Trentin:Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Octapharma: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Shire: Honoraria. Varettoni:Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees; AbbVie: Other: Travel/accommodations/expenses; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel/accommodations/expenses. Visentin:Janssen: Honoraria; Gilead: Honoraria; Abbvie: Honoraria. Falini:Roche: Research Funding. Pulsoni:Sandoz: Consultancy; Pfizer: Consultancy; Takeda: Consultancy; Gilead: Speakers Bureau; Bristol Myers Squibb: Speakers Bureau; roche: Consultancy, Speakers Bureau; Merk: Consultancy. Tiacci:Roche: Research Funding; Abbvie: Other: Travel and meeting expenses. Zinzani:Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Portola: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Servier: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; ADC Therapeutics: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Kirin Kyowa: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen-Cilag: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Verastem: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Immune Design: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; TG Therapeutics, Inc.: Honoraria, Speakers Bureau; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sandoz: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; MSD: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celltrion: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Eusapharma: Consultancy, Speakers Bureau; Kyowa Kirin: Consultancy, Speakers Bureau; Immune Design: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; EUSA Pharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Abstract: One of the major changes suggested by the World Health Organization (WHO) classification with respect to the French-American-British (FAB) proposal for myelodysplastic syndromes (MDS) was to lower the bone marrow (BM) blast count from 30 to 20%, thus eliminating the refractory anaemia with excess of blasts in transformation (RAEB-t) category. However, a general consensus has not been reached, and several authors still retain RAEB-t as an MDS sub-entity. We re-evaluated our series of 74 patients classified as RAEB-t according to the FAB criteria by stratifying them into two subsets: patients with at least 5% peripheral blast (PB) cells but with BM blasts 〈 20% (group I) and patients with BM blastosis between 20 and 30% and PBs 〈 5% (group II). We found differences among the two groups regarding sex, haematological parameters at presentation (white blood cell and neutrophil counts, haemoglobin level) and frequency of infectious episodes during the course of disease. We did not find differences as to the frequency of acute myeloid leukaemia transformation, but a significant difference was evidenced as to survival (9.3 vs. 16 months in group I vs. group II, respectively; p = 0.02). Furthermore, at our institution, we compared the RAEB-t group I patients who, based on 〉 5% PBs, should be included in the RAEB-II category according to the WHO criteria, with a group of 98 patients who were diagnosed as RAEB-II according to the WHO criteria. The findings showed that the aggregation of these two subsets appeared inappropriate, because patients of the two groups showed different clinical features and rates of acute transformation. In conclusion, the RAEB-t entity according to the FAB criteria, although including heterogeneous clinical patient subsets, should more likely be considered as an advanced stage of MDS, rather than a true acute myeloid leukaemia.