ALBERT

Description: Introduction: Anemia is the most common hematological abnormality in patients with cancer and hematological malignancies, and is associated with poor prognosis and outcomes that have a detrimental impact on the patient's condition and quality of life (QOL). Erythropoiesis-stimulating agents (ESA) represent a good treatment option in order to increase the hemoglobin level in patients with anemia. Anemia can also be treated by red blood cell transfusion, but this has a transient effect and is associated with risks such as exposure to infectious agents, iron overload, or transfusion-related acute lung injury. ESA also have safety concerns, including the established increased risk of venous thromboembolic events. However, they are currently the only therapeutic alternative to transfusions. We performed a prospective observational study in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) for hematological malignancies, with the primary objective of evaluating the effect of a new ESA biosimilar, epoetin zeta (Hospira) on patient QOL. Secondary objectives included hemoglobin (Hb) and platelet (Pt) recovery, safety, overall survival (OS) and relapse incidence. Results of this study were compared to two reference populations, one receiving epoetin beta (Roche) and one control group not treated with ESA. Here, we present preliminary results for the secondary objectives. Materials and methods: The study included adult patients with Hb level ≤11g/dl occurring after all types of allo-HSCT for any hematological disease (Table 1). Epoetin zeta (30,000 IU) was administered s.c. once per week for up to 6 months, and Hb levels were monitored weekly. Injections were stopped once the Hb level reached 12g/dl without transfusion. If after 4 injections, no improvement was observed, doses were doubled, and if after 8 injections, no improvement was observed, the patient was withdrawn from the study. The QOL was measured at baseline and at 1, 2, 3 and 6 months by the Functional Assessment of Cancer Therapy-Anemia (FACT-An) scale. Epoetin zeta responders were defined as having Hb level ≥12g/dl (complete response, CR) or a ≥2g/dl increase (partial response, PR) compared with baseline value, in the absence of transfusion. Patients receiving epoetin zeta (group 1) were compared to a similar population receiving epoetin beta with the same procedures (group 2) and to a matched population not treated with ESA (group 3), taking into account the following variables: sex, age, diagnosis, disease status at allo-HSCT, conditioning regimen and HSC source. Results: Between December 2011 and September 2014, 58 patients (from 168 screened) were included in group 1, and compared to 59 patients in group 2 and 65 patients in group 3. The main exclusion criteria were ESA contra-indication and patient refusal. Patients in group 1 had lower Hb baseline levels compared to group 2; patient characteristics for each group are summarized in Table 1. The median number of injections/patient was 10 (range: 6-14) in group 1 and 8 (range: 2-28) in group 2. The cumulative incidence of CR was 80% in group 1 and 71% in group 2. The median time to achieve CR was 48 days (range: 35-70) in group 1, and 39 days (range: 14-180) in group 2. Eight patients withdrew due to ESA inefficacy in group 1 and 8 in group 2. Adverse events were all thromboembolic: 2 events in group 1 and 5 events in group 2, compared to 2 events in group 3 (p=0.34). The multivariate analysis studying different confounding factors on the cumulative incidence of CR showed a significant positive impact of younger age (p=0.001), and a negative impact of being female or having major ABO incompatibility. We did not find any significant difference in terms of OS and relapse rate between the 3 groups. Conclusion: We describe here, for the first time, preliminary data for ESA biosimilar epoetin zeta (Hospira) in allo-HSCT patients showing comparable efficacy and safety to an existing ESA, epoetin beta (Roche) with no impact on OS and relapse incidence, compared to a control group. The QOL and transfusion evaluations as well as a cost-effectiveness study are ongoing and results will be presented. Disclosures Nicolini: Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Ariad Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Description: Introduction The acquisition of ABL1 Kinase Domain (KD) mutations represent the most frequent resistance mechanism in CP-CML patients (pts) treated with tyrosine kinase inhibitors (TKI). Currently, the standard assay relies on a poorly sensitive technique, Sanger Sequencing (SS). Thus, the detection of these mutations using SS might be too late to trigger a timely treatment change. In a national phase III academic trial (PETALs, EudraCT 2013-004974-82), we evaluated prospectively the value of a more sensitive technique, Next Generation Sequencing (NGS) to detect KD ABL1 mutations in newly diagnosed CP-CML patients randomized to get nilotinib 600 mg/d for 6 years ± Pegylated-IFN-α2a (Peg-IFN) 45 μg/wk for 2 years in combination. Methods Newly diagnosed CP CML pts ≤65 years were randomized 1:1 to get NIL 300 mg BID alone (M0 to M48, arm A) vs Peg-IFN alone for 30 days (M-1→M0) 30 mg/wk as priming, prior to NIL 300 mg BID + Peg-IFN 30 μg/wk 2 weeks, upgraded to 45 μg/wk thereafter, for up to 2 y (M0 to M24, arm B) followed by NIL alone for 4 more years unless pts enter a treatment-free remission phase. In addition to KD mutational analysis performed by SS as per protocol, patients also had KD mutational analysis performed by NGS at M3, M6, M12 and 6-monthly thereafter until achievement of a stable MMR, regardless of response. NGS assay was performed as previously described (Kizilors et al. Lancet Haematol 2019). Results Two hundred pts were randomized (99 in A, 101 in B), of which 96 patients (51/99 in A, 45/101 in B, p=0.399) underwent a KD mutational analysis performed by NGS as part of this study. The remaining 104 patients are currently being screened and the full dataset will be presented. Among the 96 patients tested, there was no difference in the distribution between the 2 arms with respect to gender, age [median 45 years (18-66)] or risk factors distribution (p=0.862 and 0.328 for Sokal and ELTS respectively in patients tested at 3 months). The median follow-up of this cohort is 45.0 (33.2-58.7) months. By 12 months, 11 patients [8/51 (11.8%) in A, 3/45 (6.6%) in B] had developed a KD mutation. After only 3 months of TKI therapy, 3 patients were found mutated (Y253H 2 pts, T315I 1 pt), of whom 2 pts were only detected using NGS. At M6, a KD mutation was found in 8 pts [A: 7 patients, B: 1 pt, (p= 0.055), of which 6/8 were not detected by SS, due to either low level Variant Allele frequency (VAF, n=5) or low level BCR-ABL transcript levels (n=1). Y253H mutations were found in 4 pts, T315I in 2 pts and E255K in 1 pt. Consecutively to KD mutation identification, 6/8 patients lost their response and were withdrawn from study (1 pt with a Y253H detected at M3 progressed to advanced phase), while 1 pt lost MMR at last follow-up and another pt with a mutation sensitive to nilotinib achieved MMR. KD mutations were detected while pts were in optimal response at M6 [BCR-ABL

Description: The combination of 2GTKI+pegylated IFN-α (Peg-IFN) is an attractive approach for first-line treatment of CP CML, inducing high rates of deep molecular responses in phase II trials. Thus, we evaluated nilotinib (NIL) alone versus NIL+Peg-IFN in newly diagnosed CP-CML patients (pts) in a randomised phase III trial (PETALs, EudraCT 2013-004974-82). Newly diagnosed CP CML pts ≤65 y, without prior history of arterial occlusion were randomized 1:1 to get NIL 300 mg BID alone (M0 to M48, arm A) vs Peg-IFN alone for 30 days (M-1→M0) 30 μg/wk as priming, prior to NIL 300 mg BID + Peg-IFN 30 μg/wk 2 wks, upgraded to 45 μg/wk thereafter, for up to 2 y (M0 to M24, arm B) followed by NIL alone for 4 more years unless pts enter treatment-free remission (TFR). The primary endpoint is the rate of MR4.5 by 1 y. As a secondary endpoint, pts reaching MR4.5 ≥2 y are allowed to stop NIL and enter a TFR phase in both arms. The trigger for treatment resumption is loss of MMR. All molecular assessments are centralised, quantifications are expressed as BCR-ABL/ABL1 (IS) in % with ≥32,000 copies of ABL1 as control. Two hundred pts were randomized (99 in A, 101 in B), 130 M and 35 F in each arm, median age of 46 (18-66) y. Median follow-up is 43.8 (34.3-55.9) Mo. Results are analysed in intention-to-treat. Sokal and EUTOS LTS scores were H in 25% and 2.5%, Int. in 33% and 16.5% and L in 42% and 81% pts respectively equally balanced. Median age is 46 (18-66) y, 18 pts (9%) had ACAs, all pts have a "Major" BCR transcript. CHR was obtained in 9.6% of pts at M0 (in B) and 88% of pts in A and 90.4% of pts in B at M1. CCyR rates at M3 were 63% vs 75% in A and B (p=ns), and BCR-ABL1 ≤1% at M6 were 87% in A vs 93% in B (p=ns). By M12, the rates of MMR were 68.1% vs 70.1% (p=0.44), MR4 were 34% vs 47.5% (p=0.041), MR4.5 were 15.9% vs 21.5% (p=0.049), MR5 11.7% vs 23.71% (p=0.023), in A vs B respectively. By M36 the rates of MMR were 83% vs 86.6% (p=0.31), MR4 were 70.2% vs 71.13% (p=0.50), MR4.5 were 37.2% vs 49.5% (p=0.05), MR5 33% vs 42.3% (p=0.12), in A vs B respectively The overall cumulative incidence of MR4.5 is superior in B (54.6 [43.7-65.5]%) vs A (44 [31.5-54]%) close to significance (unilateral Fisher test, p=0.05, see Figure). Seven patients were mutated by Sanger in A (5 Y253, 1 E255K, 1 T315I) vs 2 in B (2 T315I). One pt (A) progressed toward AP and then myeloid BC with a Y253H mutation, is still alive in CMR on Ponatinib. Twenty nine (29%) pts were withdrawn from study in A (toxicity 9, cancer 3, resistance 14, investigator decision 2, lost for FU 1) vs 26 (26%) pts for B (toxicity 13, resistance 8, investigator decision 5), 1 pt died from cervix cancer (A). Median overall doses of NIL delivered by M36 were 600 mg/d in both arms (p=ns). The median overall dose of Peg-IFN delivered in B by M24 was 37.5 mg/wk. The overall rate of grade 3-4 hematologic toxicities was 22%; with 2% and 7% thrombocytopenia, 4% and 6% neutropenia, and 1% and 1% pancytopenia in A vs B respectively. Major grade 3-4 non-hematologic toxicities consisted in 9% of cardiac disorders in A (2 coronaropathies, 1 myocardial infarction, 2 thoracic pains, 2 atrial fibrillation, 1 bradycardia, 1 palpitations, 1 pericarditis) vs 8% in B (2 coronaropathies, 1 myocardial infarction, 3 atrial fibrillation, 1 palpitations, 1 pericarditis), 4% vascular disorders in A (1 thrombophlebitis + PE, 1 transient ischemic attack, 1 PAOD, 1 carotid stenosis) vs 3% in B (1 thrombophlebitis, 1 PAOD, 1 transient ischemic attack). Three % of gastro-intestinal disorders were observed in A (2 pancreatitis, 1 anal fissure) vs 6% in B (2 pancreatitis, 1 anal fissure, 1 abdominal pain, 2 cholecystectomies); 5% auto-immune disorders in B (1 recurrent pericarditis, 2 hemolytic anemia, 1 ITP, 1 thyroiditis); 5 and 8 pregnancies (2 pts + 3 partner Arm 1, 3 pts + 5 partner Arm B), despite recommended contraceptive methods. Secondary tumours were diagnosed in 4% (1 breast, 1 cervix, 1 thyroid, 1 neuroendocrine) in A vs 2% of pts (1 neuroendocrine and 1 testis) in B. Of note 8% psychiatric episodes were reported in B pts (2 unsuccessful suicide attempts), vs 2% in A. We observed 9% lipase elevations in A, 6% in B, 2% cholestatic episodes in A, 6% in B; 3% of transaminase elevations in A vs 2% in B. Infections were detected in 3% A vs 7% in B. The combination of NIL + Peg-IFN seems to provide somewhat higher MR4.5 rates by M36 in newly diagnosed CP CML pts without inducing significant higher toxicities than NIL alone. Whether this will translate in higher TFR rates is under evaluation. Final updated results at M36 will be presented Disclosures Nicolini: Sun Pharma Ltd: Consultancy; Novartis: Research Funding, Speakers Bureau; Incyte Biosciences: Honoraria, Research Funding, Speakers Bureau. Etienne:Novartis: Consultancy, Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau; Incyte Biosciences: Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau. Huguet:Servier: Honoraria; Amgen: Honoraria; Novartis: Honoraria; Incyte Biosciences: Honoraria; Jazz Pharmaceuticals: Honoraria; Pfizer: Honoraria; BMS: Honoraria. Guerci-Bresler:Novartis: Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau; Incyte Biosciences: Honoraria, Speakers Bureau. Charbonnier:Incyte Biosciences: Honoraria, Speakers Bureau; Novartis: Consultancy; Pfizer: Consultancy. Legros:Novartis: Honoraria; Pfizer: Honoraria, Research Funding; Incyte Biosciences: Honoraria, Research Funding; BMS: Honoraria. Coiteux:Pfizer: Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau; Incyte Biosciences: Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau. Cony-Makhoul:BMS: Consultancy, Honoraria, Speakers Bureau; Pfizer: Consultancy; Incyte Biosciences: Honoraria, Speakers Bureau; Novartis: Consultancy. Roy:Incyte Biosciences: Consultancy. Rousselot:Pfizer: Research Funding; Incyte: Research Funding. Quittet:Novartis: Honoraria, Speakers Bureau. Ame:Incyte Biosciences: Honoraria, Speakers Bureau. Rea:Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte Biosciences: Honoraria; BMS: Honoraria. Dulucq:Novartis: Honoraria, Speakers Bureau; Incyte Biosciences: Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau. Mahon:Novartis: Consultancy, Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau; Incyte Biosciences: Honoraria, Speakers Bureau. OffLabel Disclosure: Pegylated Interferon alpha 2 a is not licensed in this setting

Description: Background: Allogeneic SCT is considered standard treatment for patients with advanced phase CML (accelerated phase, blast crisis), de novo Ph+ ALL, or patients in chronic phase (CP) resistant or intolerant to at least 2 tyrosine kinase inhibitors (TKI). Ponatinib is FDA and EMA approved for the treatment of CML or Ph+ ALL in patients with the BCR-ABL1 T315I mutation or for whom no other TKI therapy is indicated. In patients harboring the T315I mutation, ponatinib currently represents a suitable alternative treatment option to allogeneic SCT. However, differences in outcomes between patients treated with ponatinib and allogeneic SCT have not been analyzed. Objective: To compare overall survival (OS) among CML and Ph+ ALL patients with the BCR-ABL1 T315I mutation treated with ponatinib (in PACE) versus allogeneic SCT (in the EBMT database). Methods: Data from a Phase II trial of ponatinib (PACE trial; Cortes et al., New Engl J Med 2013; NCT01207440) and European Bone Marrow Transplant (EBMT) registry were pooled to conduct an indirect comparison of ponatinib with allogeneic SCT. Both ponatinib and allogeneic SCT cohorts comprised patients with the T315I mutation age 18 years or older in any phase of CML or with Ph+ ALL. All patients harbored the T315I mutation detected by Sanger sequencing, DHPLC, PCR-RFLP, or other equivalent tests. Allogeneic SCT patients in their second CP phase were excluded, and no patients in the EBMT database were treated with ponatinib prior to receiving allogeneic SCT. The date of intervention (ponatinib or SCT) served as the index date. Baseline demographic and clinical characteristics were compared between the two intervention groups. OS was compared between the two groups using adjusted Kaplan-Meier (KM) survival curves and multivariate Cox proportional hazards models; all comparisons were adjusted for age (as a continuous variable), gender, geographic region (Europe, Asia, and Australia vs. North America), time from CML diagnosis to intervention, and CML phase or Ph+ ALL at intervention to control confounding by these variables. Results were presented overall and stratified by phase of CML or Ph+ ALL. Results: A total of 184 (128 ponatinib, 56 allogeneic SCT) patients were included in the analysis: 90 were in CP-CML, 26 were in accelerated phase (AP-CML), 41 were in blast phase (BP-CML), and 27 had Ph+ ALL. On average, ponatinib patients were older than allogeneic SCT patients on the date of intervention (median age 53 vs. 45 years, p=0.006). In addition, a larger proportion of patients in the ponatinib group were from North America than in the allogeneic SCT group (43.8% vs. 26.8%, p=0.030). Median time from diagnosis to intervention was longer for patients treated with ponatinib compared with those treated with allogeneic SCT in CP-CML (58 vs. 32 months, p=0.029), but not significantly different in AP-CML (80 vs. 49 months, p=0.075) nor Ph+ ALL (17 vs. 10 months, p=0.212). This period was nominally shorter for the ponatinib cohort in BP-CML (26 vs. 43 months, p=0.340). Over 93% of patients in both treatment cohorts in all disease phases reported previous use of imatinib. Adjusted median OS was significantly longer in CP-CML patients treated with ponatinib as opposed to allogeneic SCT patients (KM median: not reached [NR] vs. 103.3 months, p=0.013), with a hazard ratio (HR) of 0.37 (95% CI: 0.16, 0.84, p=0.017). Median OS was not significantly different between the two treatment groups in patients with AP-CML (NR vs. 55.6 months, p=0.889; HR=0.90 [95% CI: 0.20, 4.10, p=0.889]). However, among patients with BP-CML, ponatinib was associated with significantly shorter OS compared with allogeneic SCT: median 7.0 vs. 10.5 months (p=0.026), HR=2.29 (95% CI: 1.08, 4.82, p=0.030). Ph+ ALL patients treated with ponatinib had nominally shorter median OS than allogeneic SCT (6.7 vs. 32.4 months, p=0.119; HR=2.77 [95% CI: 0.73, 10.56, p=0.136]). See Figures 1a-1d for adjusted KM survival curves. Conclusion: AllogeneicSCT remains a potential curative therapy for patients with BP-CML. However, ponatinib was associated with significantly longer OS than allogeneic SCT in patients with CP-CML that harbor the T315I mutation and could represent a promising therapeutic alternative in this setting, although follow-up remains short to date. OS was similar between intervention groups in AP-CML and longer for allogeneic SCT patients in BP-CML and Ph+ ALL. Disclosures Nicolini: Ariad Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Basak:MSD: Consultancy, Honoraria; Astellas: Honoraria; Sanofi: Honoraria; Pierre-Fabre: Honoraria. Kim:Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Il-Yang: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Pinilla-Ibarz:BMS: Consultancy, Speakers Bureau; Novartis: Consultancy; ARIAD: Consultancy; Pfizer: Consultancy, Speakers Bureau. Apperley:ARIAD: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Hughes:Novartis: Honoraria, Research Funding; BMS: Honoraria, Research Funding; ARIAD: Honoraria, Research Funding. Niederwieser:Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Mauro:Ariad: Consultancy; Pfizer: Consultancy; Novartis Pharmaceutical Corporation: Consultancy, Research Funding; Bristol-Myers Squibb: Consultancy. Chuah:Bristol-Myers Squibb: Honoraria; Novartis: Honoraria; Chiltern International: Honoraria. Hochhaus:Pfizer: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; ARIAD: Honoraria, Research Funding. Martinelli:Novartis: Consultancy, Speakers Bureau; MSD: Consultancy; Pfizer: Consultancy; Ariad: Consultancy; ROCHE: Consultancy; BMS: Consultancy, Speakers Bureau; AMGEN: Consultancy. DerSarkissian:ARIAD: Research Funding. Kageleiry:ARIAD: Research Funding. Yang:ARIAD: Employment. Huang:ARIAD: Employment, Equity Ownership. McGarry:ARIAD: Employment, Equity Ownership. Cortes:Pfizer: Consultancy, Research Funding; BMS: Consultancy, Research Funding; BerGenBio AS: Research Funding; Teva: Research Funding; Novartis: Consultancy, Research Funding; Ariad: Consultancy, Research Funding; Astellas: Consultancy, Research Funding; Ambit: Consultancy, Research Funding; Arog: Research Funding; Celator: Research Funding; Jenssen: Consultancy.

Description: ATP binding cassette (ABC) transporters are a superfamily of highly conserved membrane proteins that transport a wide variety of substrates across cell membranes and confer drug resistance against a wide range of chemotherapeutic agents. We recently found that WT1, which is regularly overexpressed in AML and interact with the splicing machinery, modifies the splicing of ABC transporters A2, A3, A5, and C2. For ABCA3, WT1 knock-down in three AML cell line coupled with Affymetrix HTA2 exon arrays analysis confirmed by exon-specific PCR revealed that WT1 influences the skipping of exon 19. ABCA3 belongs in the ABC subclass and induces a significant reduction in cytotoxicity observed following exposure to DNR, mitoxantrone, etoposide, Ara-C and vincristine. The ABCA3 domain encoded by exon 19 (amino acid 805-847) is localized at the junction of the first nucleotide-binding domain and the second transmembrane domain, and is involved in ATP hydrolysis. In silico, skipping of exon 19 deletes a sequence of 32 amino acids rich in positively charged residues and is thereby assumed to increase drug efflux through increased ATP hydrolysis. The effects of the skipping of exon 19 on chemoresistance and DNR efflux are currently investigated while for the present study, we hypothesized that skipping of exon 19 of ABCA3 might negatively influence outcome in AML patients. Analyzing 132 bone marrow AML samples harvested at diagnostic confirmed the statistically significant correlation between WT1 expression and ABCA3 splicing in vivo (p

Description: Introduction Deep molecular response (DMR) are now highly desirable goals in the treatment of CP-CML, especially in the front-line setting, because it can lead to a definitive treatment-free remission (TFR). However, such a goal is difficult to attain and does not concern the majority of patients (pts), but currently the precise number of pts able to access to TFR is unknown. Aims We aim to determine the number or newly diagnosed CP-CML pts reaching DMR, stable DMR, and access to TFR, on Imatinib (IM, Glivec®) first-line. Methods We retrospectively analyzed in an observational study, a cohort of newly diagnosed CP-CML pts treated with IM first-line 400 mg daily alone in our 3 reference centers between 2000→2018. All pts were followed according to the ELN recommendations 2006, 2010 and 2013. Clinical data were extracted from medical files, and responses (hematologic, cytogenetic, molecular) were analysed according to standard methods. Molecular results were standardised according to the ELN/Eutos programs since 2003, and were all expressed as BCR-ABLIS in %. DMR have been defined according to the ELN (NCP. Cross et al., Leukemia 2015). Stability of DMR has been defined as a stable if ≥2 years at least on 4 datapoints. TFR has been proposed to pts presenting the only current recommended criteria: MR4.5 ≥2 years at least on 4 datapoints [(Rea et al., Cancer 2018)], in the 3 centers involved, within clinical trials, pioneered in our country, or now as a clinical routine recommendation. Loss of MMR was the trigger for TKI resumption after IM cessation for TFR. Overall survival (OS), progression-free survival (PFS), failure-free survival (FFS, defined as progression to advanced phases death, loss of CHR, CCyR, or MMR, discontinuation of IM for toxicity, primary cytogenetic resistance) were analysed since IM initiation in intention-to-treat. Results Four hundred and eighteen pts have been included in this study, with a median age of 60.7 (48-70) years at diagnosis, with 57% males and 43% females. Sokal score (n=401) was low in 32%, intermediate in 51% and high in 17%. ACA were present at diagnosis in 5.5% of the pts (NA in 1.44%). Major BCR transcripts were found in 98% of pts, and atypical transcripts in 1.9%. CHR was reached in a median of 1 (0.85 to 1.64) month of IM,

Description: Background The efficacy and safety of subsequent TKIs in pts who have experienced failure of dasatinib is not fully known. Ponatinib, a pan-BCR-ABL inhibitor, was evaluated in a phase 2, international, open-label clinical trial (PACE). This post-hoc analysis explored the efficacy and safety of ponatinib following failure of dasatinib in CP-CML pts in the PACE trial. Methods The PACE trial enrolled 449 pts, including 270 with CP-CML. Pts had to be resistant or intolerant to dasatinib or nilotinib, or they had to have the T315I mutation at baseline. The primary endpoint in CP-CML was major cytogenetic response (MCyR) at any time within 12 months after treatment initiation. The trial is ongoing. Data as of 1 April 2013 are reported, with a minimum follow-up of 18 months for pts remaining on study. The efficacy and safety of ponatinib (45 mg QD) in 107 CP-CML pts following failure of dasatinib as the most recent prior therapy, irrespective of other TKI therapy, is presented (Group D). Eighteen pts who experienced failure of dasatinib but received ≥1 anticancer therapy, other than hydroxyurea or anagrelide, prior to ponatinib treatment were excluded from the analyses. Data are also presented for 2 subsets of Group D: 52 pts whose only TKI therapy was imatinib followed by dasatinib (Group I-D), and 46 pts whose only TKI therapy was imatinib, then nilotinib, and then dasatinib (Group I-N-D). An analysis of cross-intolerance was also conducted in 69 pts with prior dasatinib treatment at any time who discontinued dasatinib due to intolerance. Results Baseline characteristics are shown in the table. Group I-D tended to be younger, with less time since diagnosis versus Group I-N-D. At the time of analysis, 60%, 65%, and 54% of pts in Groups D, I-D, and I-N-D remained on study. The most common reasons for discontinuation were adverse events (AEs; 16%, 15%, 17%) and progressive disease (9%, 6%, 11%) in Groups D, I-D, and I-N-D. Efficacy end points are shown in the table. In Group D, MCyR was seen in pts with the following dasatinib-resistant mutations at baseline: V299L, 3/4 (75%); T315I, 17/23 (74%); F317L, 3/10 (30%). The most common treatment-related AEs were thrombocytopenia (44%, 37%, 57%), rash (39%, 39%, 39%), and dry skin (39%, 29%, 52%) in Groups D, I-D, and I-N-D. Serious cardiovascular, cerebrovascular, and peripheral vascular AEs occurred in 6%, 3%, and 3% of pts in Group D (treatment-related: 3%, 1%, 0%). Seventy-three of 217 pts receiving prior dasatinib at any time discontinued dasatinib due to intolerance. Of these 73 pts, 27 experienced the same AE(s) with ponatinib that led to dasatinib intolerance; 12 pts had grade 3/4 thrombocytopenia, 6 pts had other grade 3/4 AEs (3 with neutropenia, 1 each with pleural effusion, dyspnea, pulmonary hypertension), 8 pts had grade 1/2 AEs. Six of these 27 pts discontinued ponatinib due to the same AE that led to dasatinib intolerance. Thrombocytopenia was the primary AE involved in cross-intolerance (4 pts); congestive cardiac failure (grade 5) and pleural effusion each occurred once. Conclusions Ponatinib has substantial activity in pts with CP-CML following failure of dasatinib, with a safety profile reflective of this heavily pretreated population. Cross-intolerance between dasatinib and ponatinib was infrequent. Disclosures: Hochhaus: Ariad, Novartis, BMS, MSD, Pfizer: Research Funding; Novartis, BMS, Pfizer: Honoraria. Cortes:Ariad, Pfizer, Teva: Consultancy; Ariad, BMS, Novartis, Pfizer, Teva: Research Funding. Kim:BMS, Novartis,IL-Yang: Consultancy; BMS, Novartis, Pfizer,ARIAD,IL-Yang: Research Funding; BMS, Novartis,Pfizer,IL-Yang: Honoraria; BMS, Novartis,Pfizer: Speakers Bureau; BMS, Pfizer: Membership on an entity’s Board of Directors or advisory committees. Pinilla-Ibarz:Novartis, Ariad: Research Funding; Novartis, Ariad, BMS and Pfizer: Speakers Bureau. le Coutre:Novartis: Research Funding; Novatis, BMS, Pfizer: Honoraria. Paquette:ARIAD, BMS, Novartis: Consultancy, Honoraria, Speakers Bureau. Chuah:Novartis, Bristol-Myers Squibb: Honoraria. Nicolini:Novartis, Ariad and Teva: Consultancy; Novartis & Bristol Myers Squibb: Research Funding; Novartis, BMS, Teva, Pfizer, Ariad: Honoraria; Novartis, BMS, Teva: Speakers Bureau; Novartis, Ariad, Teva, Pfizer: Membership on an entity’s Board of Directors or advisory committees. Apperley:Novartis: Research Funding; Ariad, Bristol Myers Squibb, Novartis, Pfizer, Teva: Honoraria. Talpaz:Ariad, BMS, Sanofi, INCYTE: Research Funding; Ariad, Novartis: Speakers Bureau; Ariad, Sanofi, Novartis: Membership on an entity’s Board of Directors or advisory committees. DeAngelo:Araid, Novartis, BMS: Consultancy. Abruzzese:BMS, Novartis: Consultancy. Rea:BMS, Novartis, Pfizer, Ariad, Teva: Honoraria. Baccarani:Ariad, Novartis, BMS: Consultancy; Ariad, Novartis, BMS, Pfizer, Teva: Honoraria, Speakers Bureau. Müller:Novartis, BMS, Ariad: Consultancy, Honoraria; Novartis, BMS: Research Funding. Gambacorti-Passerini:Pfizer: Research Funding; Pfizer, BMS: Honoraria. Lustgarten:ARIAD: employees of and own stock/stock options in ARIAD Pharmaceuticals, Inc Other, Employment. Rivera:ARIAD: Employment. Clackson:ARIAD: employees of and own stock/stock options in ARIAD Pharmaceuticals, Inc Other, Employment. Turner:ARIAD: Employment. Haluska:ARIAD: employees of and own stock/stock options in ARIAD Pharmaceuticals, Inc Other, Employment. Deininger:BMS, ARIAD, NOVARTIS: Consultancy; BMS, NOVARTIS, CELGENE, GILEAD: Research Funding; ARIAD, NOVARTIS: Advisory Boards, Advisory Boards Other. Hughes:Novartis, BMS, ARIAD: Honoraria, Research Funding. Goldman:Ariad: Honoraria. Shah:Ariad, Bristol-Myers Squibb: Consultancy, Research Funding. Kantarjian:RIAD, Novartis, BMS, Pfizer: Research Funding.