ALBERT

Description: Introduction: The achievement of a deep and sustained molecular response after treatment with tyrosine kinase inhibitors (TKI) is one of the requirements for therapy discontinuation in chronic myeloid leukemia (CML) patients. Objectives: This study aimed to evaluate the proportion of CML patients treated with imatinib in first-line that achieve MR4.5 (BCR-ABL transcripts ≤ 0.0032% in the international scale) after imatinib treatment and the predictive factors for this response. The secondary objectives were to evaluate the rate of MMR (PCR ≤0.1%), MR4.0 (PCR ≤ 0.01%), time to molecular responses, event-free survival, progression-free and overall survival. Patients and methods: This is a retrospective analysis of CP-CML patients treated in first-line with imatinib in a single center. Patients diagnosed after 2006 were managed according to the European Leukemia Net recommendations. All patients started CML imatinib within six months from diagnosis. The type of BCR-ABL1 transcript was determined by multiplex RT-PCR from cDNA synthesized from total leukocytes RNA at diagnosis. BCR-ABL transcripts by quantitative real-time polymerase chain reaction were assessed at baseline, and then every three months for the first year until reaching a stable major molecular response, then every 3-6 months. The SPSS software was used for the Cox Regression model for univariate and multivariate analysis, using backward Wald. The cumulative incidence was calculated with the R Program, with Gray test for curve comparisons. Event-free, progression-free and overall survivals were calculated with the Kaplan-Meier method, and the curves were compared with the log-rank test. Results: From January 2005 to December 2015 172 patients were treated with imatinib, median age 48 years (18-93), 55.8% male. Sokal score: 31% low-risk, 40% intermediate-risk and 29% high-risk. The median follow-up was 56 months (0-157). The Cumulative Incidence (CI) of MMR was 48% in 24 months and 84% in 5 years, while the CI of MR4.0 and MR4.5 was 63% and 51%, respectively, in 5 years. The median time to MMR, MR4.0 and MR4.5 was 16.7 (2-102), 31 (5-150) and 36 months (7-153), respectively. The univariate regression factors related to MR4.5 achievement were: age 〉48 years (HR 1.79; 95%CI: 1.08-2.98; P=0.023); days between diagnosis and imatinib start (HR=0.99; 95%CI: 0.98-0.99, P=0.020); e14a2 (b3a2) transcript (HR= 3.37; 95%CI: 1.67-6.81; P=0.001), which was the only factor in the multivariate analysis. Imatinib was discontinued in 96/172 (55.8%) patients due to resistance (36.5%), intolerance (20.8%), clinical trials (25%), death (15.6%) and adherence (2.1%). Eighteen out of 67 (26.8%) patients that achieved MR4.5 are currently participating in a discontinuation trial. Overall survival, PFS and EFS were 92%, 87% and 61% in 5 years. Conclusion: Approximately half of the patients that start imatinib in first-line obtain deep molecular responses within five years and could be candidates for treatment discontinuation. B3a2 transcript was an independent factor for MR4.5 achievement in the multivariate analysis, confirming the results of other studies that have reported earlier and deeper molecular responses in patients with b3a2 transcripts. Disclosures De Paula: Hematology and Transfusion Medicine Center, University of Campinas: Employment. Pagnano:Abbvie: Consultancy; EMS: Other: Financial support for participation in congress; Shire: Other: Lecture; Novartis: Consultancy.

Description: The prognostic significance of BCR-ABL1 transcripts in chronic myeloid leukemia (CML) is controversial. A recent report demonstrated that patients with e13a2 transcripts have inferior outcomes with imatinib 400 mg and those patients with e14a2 or that express both transcripts have more chance of an optimal response and longer event-free and transformation-free survival, while others do not confirm this data.The aim of this study was to evaluate the impact of BCR-ABL transcript type in CML patients outcome.Patients and methods: all consecutive CML patients in chronic phase treated with imatinib 400 mg/day from February 2004 to January 2016 were enrolled. Patients' responses were monitored with cytogenetic analysis at 3, 6 and 12 months, then every six months until a complete cytogenetic response (CCR). Real-time polymerase chain reaction was assessed at baseline, then every 3 months for the first year until reaching a stable major molecular response, then every 3-6 months. Demographic and baseline disease characteristics were collected at diagnosis. The type of BCR-ABL1 transcript was evaluated by multiplex RT-PCR from cDNA synthesized from total leukocytes RNA at diagnosis. We included patients with BCR-ABL transcripts e13a2, e14a2, and with coexpression of e13a2 and e14a2. Statistical analysis: Event-free survival (EFS) was measured from the start of treatment until loss of complete hematologic response, loss of major cytogenetic response, progression to accelerated (AP) or blast phase (BC) or death from any cause at any time while on initial therapy. Overall survival (OS) was measured from the start of imatinib until to the date of death from any cause at any time or last follow-up. Transformation-free survival (TFS) was measured from the start of imatinib to transformation to AP or BC or deaths while on therapy. The differences between variables were analyzed by the χ2 and the Kruskal-Wallis tests for categorical and continuous variables. Survival probabilities were calculated using the Kaplan-Meier method and compared by the log-rank test. The Cox regression estimated the hazard ratio values. All analysis considering p-value 〈 0.05 and using SPSS 21.0 software. Results: A total of 190 patients were treated with imatinib 400 mg/day. Median age was 48 years (18-87) and Sokal risk was high in 47/151 patients (31%), intermediate in 55/151 (36%) and low in 49/151 (33%). Twenty patients were excluded from the analysis: 14 patients due to Interferon treatment before Imatinib; two patients that started imatinib after six months from diagnosis; two patients with e1a2 transcripts and two patients with no RT-PCR test available at diagnosis. The remaining 170 patients presented typical BCR-ABL1 transcripts: e13a2 (n=56; 33%), e14a2 (n=94; 55%) and both transcripts (n=20; 12%). A total of 44 (26%) patients discontinued imatinib and 24 (14%) switched to second-line tyrosine kinase inhibitor. No differences were observed in sex, age, leukocytes, hemoglobin and platelets count at diagnosis, Sokal or EUTOS score according to transcript type. The proportion of patients with e13a2, e14a2 and both achieving complete cytogenetic response at 6 months was 19/44 (43%); 42/60 (70%) and 9/14 (64%) (P=0.02); and at 12 months was 28/45 (62%); 47/60 (78%) and 11/14 (78%) (P=0.16). However, the proportion of patients with major or lower molecular responses at 18 months was 13/24 (54%), 25/36 (69%) and 6/9 (66%), which was not significantly different. There were no statistical difference in EFS, PFS, and OS among the e13a2, e14a2 and e14a2+e13a2 groups. However, there was a superior 10-year overall survival in patients with transcripts e13a2 compared to e14a2 (alone or coexpressed with e13a2) (93% vs. 73%, P=0.03), although the 5-year overall survival was 96% vs. 88%, respectively (P=NS). In the multivariate analysis, high/intermediate Sokal score and e14a3/e14a3+e14a2 were independent factors for poor OS (P=0.023 and 0.041, respectively).Conclusion: The type of BCR-ABL transcripts did not affect molecular responses. Although patients with e14a2 transcripts presented higher rates of CCR at 6 months, compared to e13a2 or both transcripts, at long term, there was a superior overall survival among patients with transcripts e13a2 compared to e14a2 (alone or coexpressed with e13a2). The biological mechanism responsible for that difference is not known and should be investigated in larger trials. Disclosures Pagnano: Novartis: Consultancy, Honoraria; Bristol-Meyers Squibb: Consultancy, Honoraria.

Description: Introduction : Treatment with tyrosine kinase inhibitors (TKIs) has dramatically increased the overall survival of patients with chronic myeloid leukemia (CML) but second generation TKI has been associated with an increased risk of cardiovascular events. Objectives: The aim of this study was to evaluate the incidence of cardiovascular adverse events (CVE) in CML patients treated with TKIs and to correlate with the cardiovascular (CV) risk of the patients. Methods: this is a retrospective analysis of consecutive CML patients treated with TKIs between 2005 and 2013at our Institution. Baseline risk factors for CV diseases were collected at baseline and included age, arterial hypertension (AH), dyslipidemia, obesity, hypothireoidism, smoking, diabetes mellitus (DM), coronary artery disease and chronic renal failure. Cardiovascular events during TKI treatment were collected and included: myocardial infarction, unstable angina, peripheral arterial disease, stroke, arrythmia,hypertension and cardiac failure. Cardiovascular risk was calculated using the SCORE chart of the European Society of Cardiology and patients were classified in low, moderate, high and very high risk. Results: We analyzed CML patients treated with imatinib (n=117), dasatinib (n=91) and nilotinib (n=60). The median time of follow-up was 748, 519 and 851 days, respectively. Baseline risk factors: 90 patients (38,5%) had hypertension, 34 (14,5%) DM, 67 (28,6%) dyslipidemia, 51 (21,8%) obesity, 22 (9,4%) hypothyroidism, 14 (6%) coronary arterial disease, 21 (9%) systolic cardiac dysfunction, 4 (1,7%) stroke, 20 (8,5%) chronic kidney failure and 36 (15,4%) were smokers. SCORE chart classification: 106 patients (39,5%) were in the low-risk category, 70 (26%) in the moderate risk, 46 (17,2%) in the high risk, 46 (17,2%) in the very high risk group. Overall, the cumulative incidence of CVE was 4.1%. Five (5.5%) events occurred during dasatinib treatment (P=0.015), 6 (10%) events during nilotinib and no events during imatinib treatment (P=0.001). The incidence of CVE was 10.8% in the high and very high-risk groups and 0.52% in moderate and low risk group (P≤0.001). The incidence of arterial ischemic events (AIE) was 10% (n=6) in patients treated with nilotinib, 2.2% (n=2) with dasatinib and 0% with imatinib (P≤0.001). Arterial events were exclusively observed in high and very high-risk groups (8 events, 8.7%) (P≤0.001). The risk factors associated with a higher risk of CVE were hypertension (P≤0.001), dyslipidemia (P≤0.001), coronary arterial disease (P=0.003), congestive heart failure (P=0.002) and chronic renal failure (P=0.011). Disease progression was the main cause of death in all groups. Conclusions: CVE were more frequent in patients treated with second generation TKIs. AIE were more frequent in patients treated with nilotinib, in those having a high or very high risk SCORE. The CV risk stratification of CML patients before and during TKI therapy can help in TKI selection and to identify patients at high risk, in order to reduce the morbidity and mortality associated with CVE. Disclosures Pagnano: Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol Miers-Squibb: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.