Rambaldi, Alessandro

Abstract Background and purpose of the study: Several reports have documented that histone deacetylase inhibitors induce neoplastic cells to undergo growth arrest, differentiation and/or apoptotic cell death. Among these agents, Givinostat inhibits proliferation of cells bearing the JAK2V617F mutation and has shown clinical significant activity with good tolerability in patients with chronic myeloproliferative neoplasms, including polycythemia vera (PV). In two phase II studies [Rambaldi et al. Br J Haematol 2010;150:446, Finazzi et al. Br J Haematol 2013;161:688] the maximum administered dose (150 mg/day) was generally well tolerated. Assuming a linear relationship between dose and efficacy, greater clinical efficacy could be expected with increased doses of Givinostat. Methods: This is a two-part, multicenter, open label, non-randomized, phase Ib/II study to assess the safety and tolerability, maximum tolerated dose (MTD) and preliminary efficacy of Givinostat in patients with JAK2V617F positive PV. Part A (i.e. phase Ib) is the dose escalation portion of the study, while Part B assesses the preliminary clinical efficacy of Givinostat at the MTD defined in Part A. Eligible patients for this study include JAK2V617F positive PV patients, who have active and/or uncontrolled disease, defined as: (i) Hematocrit (HCT) ≥ 45% or HCT <45% normalized by phlebotomy, and (ii) PLT > 400 x109/L, and (iii) WBC > 10 x109/L. Study therapy is administered in 28 day cycles (cycle is defined as 4 weeks of treatment). Disease response has been evaluated according to the clinico-haematological European LeukemiaNet (ELN) criteria [Barosi et al. Blood 2009;113:4829] at Cycles 3 and 6. Disease-related symptoms have been reported directly by the patients who completed the MPN-SAF QoL form. The study lasts up to a maximum of 24 weeks of treatment. However, after completion of the trial, all patients achieving clinical benefit are allowed to continue treatment with Givinostat in a long-term study (ClinicalTrials.gov ID: NCT01761968). In Part A, the Cycle 1 has been used to define the MTD of Givinostat. Only dose limiting toxicities (DLTs) experienced during Cycle 1 were considered for dose escalation decisions. Part B is the cohort expansion part of the study to assess the preliminary clinical efficacy of Givinostat at the MTD in evaluable patients Results: In Part A, 12 patients with active and/or uncontrolled disease, were treated with Givinostat, 6 patients at DL1 (100 mg b.i.d.), 3 patient at DL6 (150 mg/die) and 3 patients at DL0 (50 mg b.i.d.). Only one DLT .(grade 3 dyspepsia) was observed in the 6 patients treated at DL1 during the Cycle 1. Givinostat treatment was generally well tolerated: one patient developed grade 4 and two patients grade 3 thrombocytopenias at DL1 after the Cycle 1. Complete/partial response was observed in 100% of evaluable patients at Cycle 3 (Figure). At that time, an important reduction of WBC and PLT count (about 50% in both cases), an HCT control without phlebotomy, a net decrease of MPN-SAF total score and JAK2V617F allele burden (about 50% and 30%, respectively) have been noted and generally maintained at Cycle 6. One out of 3 (33%) patients with splenomegaly at baseline normalized the spleen at Cycle 6. PK/PD evaluations are currently under analysis. Part B started on December 2015 and is currently recruiting patients. At the time of ASH Meeting, a presentation of the preliminary results of the interim analysis (IA) is planned. The objective of this IA is to evaluate the response rate of the first 12 treated and evaluable patients. Conclusions: Taking into account the continuous schedule of the drug as prescribed in this current study, the daily dosage of 200 mg has been identified as the MTD of Givinostat in PV patients. Givinostat treatment is generally well tolerated and shows preliminary clinical efficacy in PV patients with an active/uncontrolled disease. Response rate of patients in Part A C3D28 = Cycle 3 Day 28, or three months of treatment. C6D28 = Cycle 6 Day 28, or six months of treatment. Two patients dropped-out the study Part A, due to Informed Consent Form withdrawal, while 1 patient left the study for AE (i.e. grade 3 dyspepsia, DLT). At C3D28, 1 Complete Response (CR) and 8 Partial Response (PR) have been observed. At C6D28, 1 Complete Response (CR), 7 Partial Response (PR) and 1 No Response (NR) have been observed Figure Figure. Disclosures McMullin: Novartis: Honoraria, Speakers Bureau. Vannucchi:Novartis: Honoraria, Speakers Bureau. Mesa:Ariad: Consultancy; CTI: Research Funding; Galena: Consultancy; Celgene: Research Funding; Promedior: Research Funding; Novartis: Consultancy; Incyte Corporation: Research Funding; Gilead: Research Funding. Tibes:Italfarmaco S.p.A.: Consultancy, Honoraria. Bettica:Italfarmaco S.p.A.: Employment. DI Tollo:Italfarmaco S.p.A.: Employment.

Abstract Abstract 1731 Background: Symptom burden in primary, post-ET and post-PV myelofibrosis (MF) is frequently severe and correlates with a poor prognosis. However, symptom manifestations are heterogeneous with variable presence of specific symptoms, splenomegaly and cytopenias. We sought to identify the spectrum and features of MF symptomatic phenotypes by cluster analysis of prospectively gathered information on MF symptoms and disease features. Methods: Data was collected among an international cohort of subjects with MF. Data included demographics, disease features and completion of the Brief Fatigue Inventory (BFI) and Myeloproliferative Neoplasm Symptom Assessment Form Total Symptom Score (MPN-SAF TSS) (Blood 2011; 118:401–408). Surveyed symptoms addressed key disease features on a 0 (absent) to 10 (worst-imaginable) scale. Cluster development was based on consideration of r-squared in hierarchical clustering using Ward's linkage. Final cluster assignment was based on the nonhierarchical k-means method. Comparisons between symptom clusters were based on ANOVA and chi-squared tests. Results: Subject Demographic and Disease Characteristics: Data from 329 prospectively enrolled persons with MF was collected (Chinese 102, French 54, German 19, Italian 22, Dutch 45, English 51, Spanish 29, Swedish 7) including 223 PMF, 67 post-ET MF and 39 post-PV MF patients. Participants were of typical age (mean 59) and gender (47% F). Among all participants, four natural symptom clusters were identified (Figure 1). Among clusters, disease features including leukopenia, thrombocytopenia, and enlarged spleen varied significantly between clusters (P<0.05). Cluster 1: The “Fatigue Dominant with Few Lab Abnormalities” Profile (n=150 (46%; 69% PMF, 20% post-ET MF, 11% post-PV MF)). Cluster 1, the largest, is characterized by fatigue-dominant complaints in the setting of the lowest overall MPN-SAF TSS and highest proportion of males (59%). Individuals among this group have the lowest prevalence of laboratory abnormalities (65% total; anemia, 67%; thrombocytopenia, 20%) or clinical deficiencies including enlarged spleen (average 6.0 cm below costal margin), prior thrombosis (9%), prior hemorrhage (5%) or prior RBC-transfusions (20.4%). Interestingly, individuals in this group are most likely to have had prior splenectomy (5.8%). Cluster 2: The “Cognitive Complaints with Enlarged Spleen” Cluster (n=105 (32%; 65% PMF, 20% post-ET MF, 15% post-PV MF)). Cluster 2 is the 2nd largest cluster. Subjects have relatively few abnormal lab values (67% vs 65%–77%) but have high severity of fatigue, sexual difficulties, insomnia, inactivity and reduced QOL. These individuals have the largest spleen size (8.7cm below costal margin). Cluster 3: The “Nighttime and Cognitive Complaints” Group (n=53 (16%; 64% PMF, 25% post-ET MF, 11% post-PV MF)). Cluster 3 is the smallest cluster. Subjects have many cognitive and nighttime-related complaints including sexual difficulties, night sweats, insomnia, and concentration problems. Subjects with post-ET MF are predominant. This cluster also has the 2ndsmallest spleen size (7 cm) or history of prior thrombosis (9.6%), hemorrhage (7.8%) or requirement for transfusions (21.2%). Cluster 4: The “Severe Fatigue with Few End-organ Complaints” Cluster (n=21 (6%; 81% PMF, 14% post-ET MF, 5% post-PV MF)). Cluster 4 is the most symptomatic cohort with the highest proportion of subjects with PM. There is a lower frequency of end-organ complaints including abdominal pain, cough, and headaches. Symptoms including sexual difficulties, sad mood and insomnia are predominant. No subjects had prior splenectomy. Subjects also have the highest prevalence of prior thrombosis (29%), hemorrhage (14%), and transfusions (43%). Additionally, this cohort has the largest prevalence of lab abnormalities (77%) with thrombocytopenia (71%), leukopenia (41%) and anemia (41%). Conclusion: This analysis will allow us to examine a new framework for evaluating persons with MF using symptom profiles and is the 1st cluster evaluation of MF. Lab and physical findings contrast significantly between symptom clusters indicating these phenotypic symptoms likely result from etiological factors present in specific disease phenotypes. Future studies should evaluate whether there is a correlation between cluster profiles, prognosis and genotype. Disclosures: Kiladjian: Celgene: Research Funding; Novartis: Honoraria, Research Funding; Shire: Honoraria. Roy:Novartis, BMS: Speakers Bureau. Harrison:Novartis: Honoraria, Research Funding, Speakers Bureau; YM Bioscience: Consultancy, Honoraria; Sanofi Aventis: Honoraria; Shire: Honoraria, Research Funding. Vannucchi:Novartis: Membership on an entity's Board of Directors or advisory committees. Passamonti:Novartis: 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; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees. Mesa:Incyte: Research Funding; Lilly: Research Funding; Sanofi: Research Funding; NS Pharma: Research Funding; YM Bioscience: Research Funding.

Abstract Abstract 2849 Background We have previously reported on the natural history of polycythemia vera (PV), focusing primarily on overall and leukemia-free survival (ASH Annual Meeting Abstracts. 2011;118(21):277-). In the current study, we present, on behalf of the International Working Group for Myeloproliferative neoplasms Resarch and Treatment (IWG-MRT), our analysis regarding risk factors for thrombosis. Methods Under the auspices of IWG-MRT, seven international centers of excellence for myeloproliferative neoplasms participated in the current study. The two principle investigators (AT and TB) reviewed all the cases and selected 1,545 patients who met the 2008 WHO criteria for PV, were age 18 years or older, diagnosed after 1970, and whose submitted data included diagnostically essential information. Results I: Presenting Features Median age was 61 years (range, 18–95; 51% females). Arterial and venous thrombosis history before or at diagnosis was documented in 246 (16%) patients and 114 (7.4%) patients, respectively. Major hemorrhage hemorrhage before or at diagnosis was documented in 17 (4.5%) patients. Other features at diagnosis included pruritus (36%), microvascular disturbances (28.5%), palpable splenomegaly (36%), abnormal karyotype (12%), leukoerythroblastosis (6%), increased LDH (50%), thrombocytosis (53%), extreme thrombocytosis (platelets >1 million mm3; 4%) leukocytosis (49%), JAK2 V617F (95%), other JAK2 mutations (3%), subnormal serum erythropoietin (Epo) level (81%), and endogenous erythroid colonies (EEC; 73%). History of hypertension (46%), hyperlipidemia (18.3%), diabetes (8.4%), and tobacco use (16%) was also obtained. Results II: Clinical Course To date, 347 (23%) deaths, 50 (3%) leukemic progressions, and 138 (9%) fibrotic transformations have been recorded. Overall, cytoreductive treatment was not used in 416 (27%) patients and the remaining were exposed to different agents based on physician discretion. Post-diagnosis arterial or venous thrombosis occurred in 184 (12%) and 137 (9%) patients, respectively. Results III: Risk Factors for thrombosis Arterial and venous thrombosis-free survival, from time of diagnosis, were separately analyzed using the occurrence of thrombosis as the endpoint (uncensored variable) and last follow-up or death before thrombosis as the censored variable. In univariate analysis, the following were significantly associated with post-diagnosis arterial thrombosis: advanced age, leukocyte count, presence of a leukoerythroblastic smear (LES), history of hypertension and history of arterial thrombosis before or at diagnosis; multivariable analysis using all these five parameters identified arterial thrombosis history (RR 2.5, 95% CI 1.6–4.0; p<0.0001), LES (RR 2.3, 95% CI 1.3–4.2; p=0.005) and history of hypertension (RR 1.6, 95% CI 1.1–2.4; p=0.02) as independent predictors of post-diagnosis arterial thrombosis. Only two parameters predicted post-diagnosis venous thrombosis, in univariate analysis, and both remained significant during multivariable analysis: abnormal karyotype (RR 3.1, 95% CI 1.7–5.4; p=0.0001) and history of venous thrombosis (RR 2.4, 95% CI 1.2–4.9). Of note, the type of JAK2 mutation or presence of either subnormal Epo or EEC did not influence either arterial or venous thrombosis. Results IV: Risk Stratification for arterial and venous thrombosis The figures below illustrated arterial or venous thrombosis-free survival of patients stratified by the absence of all risk factors or presence of one or ≥2 risk factors. For arterial thrombosis, the presence of ≥2 risk factors clearly delineated a high risk group (RR 3.1, 95% CI 1.9–5.0) whereas the presence of one (RR 2.4, 95% CI 1.4–4.2) or two risk factors (RR 10.1, 95% CI 3.6–28.2) for venous thrombosis delineated an intermediate and high risk group, respectively. Conclusions: History of arterial thrombosis and venous thrombosis are key risk factors, respectively, for recurrent arterial and venous thrombosis in PV. In addition, abnormal karyotype is a strong independent risk factor for venous thrombosis and the presence of leukoerythroblastosis and hypertension, for arterial thrombosis. This information allows for a simple and practical risk stratification and raises interesting pathogenetic implications that require further clarification. Disclosures: Vannucchi: Novartis: Membership on an entity's Board of Directors or advisory committees. Gisslinger:Novartis: Consultancy, Research Funding, Speakers Bureau; Celgene: Consultancy, Research Funding, Speakers Bureau. Passamonti:Novartis: 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; Sanofi-Aventis: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Abstract Abstract 2852 Background: The 18-item Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF, Scherber et al Blood 2011) given in conjunction with the 9-item Brief Fatigue Inventory (BFI, Mendoza et al Cancer 1999) is a patient-completed questionnaire for assessing symptoms in persons with MPNs. The MPN-SAF has been translated and validated in 9 languages to date. The Total Symptom Score (TSS) is computed from 10 of the most pertinent MPN-SAF items to assess symptom burden in MPN patients and to evaluate response to therapy. Psychometric properties of the TSS have been previously reported (Emanuel et al Blood 2012). The purpose of this analysis is to compare MPN-SAF symptoms and psychometric properties of the TSS across 9 languages in an international sample. Methods: Data were collected in an international cohort of subjects with MPNs. Surveyed symptoms included fatigue, early satiety, abdominal pain and discomfort, inactivity, headaches, concentration, dizziness, extremity tingling, insomnia, sexual problems, mood changes, cough, night sweats, pruritus, bone pain and fever on a 0 (absent) to 10 (worst imaginable) scale. TSS was computed using the published scoring algorithm on a 0 (all symptoms absent) to 100 (all symptoms worst imaginable) scale. Demographic and disease-related data including disease type, gender, and age had to be present to be included in analysis. Demographics were compared across languages groups using ANOVA and chi-squared tests. Symptoms and TSS were compared across language groups using a general linear model adjusting for disease type, age, and gender with post-hoc Tukey pairwise comparisons. Internal consistency and factor structure of the TSS were investigated overall and within language groups using Cronbach's alpha and principal-axis factoring analysis. Results: Subject Demographics and Disease Type: 1,851 subjects with polycythemia vera (PV N=655), essential thrombocythemia (ET N=769) and myelofibrosis (MF N=427; 286 primary MF, 61 PV-MF, 80 ET-MF) were prospectively enrolled and administered the MPN-SAF and BFI in 1 of 9 languages: English [UK] 55, English [US] 102, Italian 186, Swedish 114, German 112, French 457, Spanish 192, Dutch 236, and Chinese 397. Age (median 61, range, 15–94) and gender (55% F) were typical. Disease type and age varied across language groups (both p <0.001). MPN-SAF Symptoms and TSS: Symptom frequencies ranged from 19% (fever) to 88% (fatigue) overall with mean severities ranging from 0.4 (SD=1.3, fever) to 4.3 (SD=2.3, fatigue). Fatigue had the highest mean severity among all symptoms within each language group. Overall, mean TSS was 21.5 (SD=16.7) with the Swedish (mean=18.1, SD=15.2) and Dutch (mean=27.6, SD=17.1) cohorts reporting the lowest and highest unadjusted TSS means, respectively. When comparing symptom items across languages (adjusting for disease type, age, and gender), concentration and sexual problems had the most statistically significant pairwise differences (11 and 10, respectively, out of a possible 36) followed by dizziness and overall quality of life (9 each, out of a possible 36). No statistically significant pairwise differences were observed for abdominal discomfort, headache, extremity tingling, or insomnia. For the TSS, the Dutch cohort appeared to statistically significantly differ (all p <0.05) with all other languages except the English cohorts. All other TSS pairwise comparisons were not statistically significant. TSS Internal Consistency and Factor Structure: The TSS had excellent internal consistency overall (Cronbach's alpha 0.83) as well as within language groups (Cronbach's alpha 0.81–0.86). Overall factor analysis identified a single underlying construct among the 10 TSS items. Factor loadings ranged from 0.41 for fever to 0.73 for inactivity. A single factor solution was appropriate for each language group with factor loadings ranging from 0.18 to 0.85. Conclusion: This analysis suggests that the available translations of the MPN-SAF are generally acceptable for use in a broad context. The TSS demonstrated acceptable internal consistency and similar factor structure across all language groups. Most symptom and TSS comparisons between languages were not statistically significant, but for the few which differed, further studies are needed to evaluate whether these variances are due to disease-related factors or due to linguistic or cultural influences present in the cohorts. Disclosures: Kiladjian: Novartis: Honoraria, Research Funding; Celgene: Research Funding; Shire: Honoraria. Griesshammer:Shire: Honoraria. Roy:Novartis, BMS: Speakers Bureau. Harrison:Novartis: Honoraria, Research Funding, Speakers Bureau; YM Bioscience: Consultancy, Honoraria; Sanofi Aventis: Honoraria; Shire: Honoraria, Research Funding. Passamonti:Novartis: 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; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees. Mesa:Incyte: Research Funding; Lilly: Research Funding; Sanofi: Research Funding; NS Pharma: Research Funding; YM Bioscience: Research Funding.

Abstract Abstract 1726 Background: We previously reported that symptom burden among persons with ET and PV can be severe and adversely affect QOL. The presence of severe symptoms is linked to poor prognosis. There is considerable inter-subject heterogeneity regarding which symptoms are present in which subjects. No studies have empirically evaluated whether disease characteristics can be grouped in related symptom clusters. Using our previously validated 18 item Myeloproliferative Neoplasm Assessment Form (MPN-SAF) (Blood 2011;118:401–408) given in conjunction with the 9 item Brief Fatigue Inventory (BFI) (Cancer 1999;85:1186–1196), we sought to evaluate symptom burden by means of cluster analysis. Methods: Data was collected from an international cohort of subjects with MPNs including demographics, disease features and the completed BFI and MPN-SAF instruments. Surveyed symptoms included fatigue, early satiety, abdominal pain and discomfort, inactivity, headaches, concentration, dizziness, extremity tingling, insomnia, sexual difficulties, mood changes, cough, night sweats, pruritus, bone pain and fever on a 0 (absent) to 10 (worst-imaginable) scale. Development of symptom clusters was based on consideration of r-squared in hierarchical clustering using Ward linkage. Final cluster assignment was based on the nonhierarchical k-means method. Comparisons between symptom clusters were based on ANOVA and chi-squared tests. Results: Subject Demographic and Disease Characteristics: Data from 1,141 subjects with PV (N=519) and ET (N=622) was prospectively collected (Chinese 236, French 305, German 45, Italian 114, Dutch 191, English 56, Spanish 109, Swedish 85. Age (mean 59, range, 26–87) and gender (54% F) were typical. Five clusters were selected (Figure 1). Frequencies of prior bleeding, spleen size, anemia, presence of any lab abnormality, language, gender, and MPN type varied significantly between clusters (P<0.05). Cluster 1: The “Reduced Symptom” Profile (n=421 (37%; 60% ET, 40% PV) The largest cluster, subjects had increased complaints of sexual difficulties and fatigue. There was a slightly higher proportion of subjects with ET (60%) versus PV. There were fewer lab abnormalities (28% prevalence) and less prior bleeding (3%) compared to other clusters. Spleen size was smallest of the cluster (1 cm below costal margin). Cluster 2: The “Fatigue-dominant” Group (n=286 (25%; 56% ET, 44% PV)). Subjects in this cluster were predominantly female and had relatively few laboratory abnormalities (19%) than other cohorts. They are characterized by high severity of fatigue compared to end-organ symptoms. Symptom profiles emphasize fatigue, QOL and insomnia with some end-organ complaints. The cohor 63% of the cohort. Cluster 3: The “End-Organ Complaints” Group (n=210 (18%; 49% ET, 51% PV)). Male predominant (56%), subjects had mainly macro-vascular symptom complaints including sexual difficulties, insomnia, and overall QOL, with few microvascular related symptoms (low itching/night sweats). Cluster 4: “Cognitive Complaints” Cluster (n=110 (10%; 53% ET, 47% PV)). The smallest cluster and female predominant (64%), main complaints include fatigue, insomnia, loss of concentration, numbness, and sad mood. Cluster 5: The “Highly Symptomatic” Cluster (n=114 (10%; 44% ET, 56% PV)). Subjects had many cognitive complaints and symptoms correlated with severe micro-vascular abnormalities (pruritus) and or splenomegaly. This cluster had the largest spleen sizes (mean 3 cm), the highest prevalence of prior thrombosis (29%), and highest frequency of lab abnormalities (43%). Cognitive and end-organ complaints were rated as most severe. Conclusion: This analysis offers new means of evaluating persons with PV and ET utilizing symptom clusters. Laboratory and physical abnormalities differed significantly between symptom clusters indicating that our groupings likely result from biological alterations present in specific disease phenotypes. Future studies should investigate correlations between clusters and prognosis and genotype. Disclosures: Kiladjian: Celgene: Research Funding; Novartis: Honoraria, Research Funding; Shire: Honoraria. Roy:Novartis, BMS: Speakers Bureau. Harrison:Novartis: Honoraria, Research Funding, Speakers Bureau; YM Bioscience: Consultancy, Honoraria; Sanofi Aventis: Honoraria; Shire: Honoraria, Research Funding. Vannucchi:Novartis: Membership on an entity's Board of Directors or advisory committees. Passamonti:Novartis: 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; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees. Mesa:Incyte: Research Funding; Lilly: Research Funding; Sanofi: Research Funding; NS Pharma: Research Funding; YM Bioscience: Research Funding.

Abstract BACKGROUND: The presence of constitutional symptoms has been associated with increased mortality risk in myelofibrosis (MF) (Blood 2010;115(9):1703-8). New therapies exist which alleviate the severe symptom burden profile observed in MF patients but are only approved for use in those with intermediate-2 or high risk disease (N Engl J Med 2012;366:787-798). However, it has been proposed that there are patients who may benefit from symptom based treatment regardless of prognostic score (Am Soc Hematol Educ Program 2014;2014:277-286). We have recently characterized symptom score cutoffs at which patients would statistically benefit from treatment based on symptom scores alone (Scherber et. al. EHA 2016: a2250). These treatment thresholds included aMyeloproliferative Neoplasm Symptom Assessment Form Total Symptom Score (MPN-SAF TSS or MPN-10) total score of greater than or equal to 20, a worst individual item score of greater than 5, or a combined criteria of those with both an MPN-10 total score of greater than or equal to 20 and a worst individual item score greater than 5. This abstract represents an additional analysis of our MF cohort to better characterize the profile of patients who meet criteria for symptom-based therapy. METHODS: Patient demographics, symptom burden via the MPN-10 score (JCO 2012;30(33)4098-103), and disease traits were collected from MF patients and their physicians at a single time point during therapy. Previously we identified MPN-10 cutoffs via AkaikeÕs Information Criterion (AIC) analysis (Ecology 2014;95: 631-6), which represented the optimal model among all models specified for the data at hand to determine which patients would most benefit from symptom-directed therapy. RESULTS: Demographics. 695 MF patients without previousruxolitinib therapy were included in this analysis. Overall, of 455 patients (65.4%) fit a cutoff of having a single worst symptom item of greater than 5/10. 401 patients (57.7%) had a MPN-10 score of equal to or greater than 20. A total of 381 (54.8%) patients fit both of these criteria. A distribution of worse MPN-10 individual scores is shown in Table 1. Mean TSS score was 26.4 (SD=17.7). Symptom Criteria Associations. Demographics and disease traits: Neither mean age or age greater than 60 was significantly associated with meeting any of the symptom score cutoff criteria. Females were significantly more likely to meet any of the symptom score cutoffs (for all criteria, p=0.0003 or less). Patients with splenomegaly, particularly spleen size of greater than 15cm below the LCM, were significantly more likely than those with a normal sized spleen to meet any of the three criteria (spleen enlargement of any size p=0.014 or less; spleen greater than 15cm p=0.0114 or less). Patients who met any of the three symptom criteria tended to have a longer MPN duration, although this trend did not meet significance. A prior history of thrombosis was not associated with achieving any cutoff criterions. Symptom burden: Individuals who met the any symptom criteria were significantly more likely to have higher DIPSS prognostic risk score (for all p=0.0002 or less). Laboratory values: For those meeting criteria for a worst symptom greater than 5, mean WBC was 11.7 vs 9.1 x 109/L (p=0.025) and platelet count was 238.7 versus 329.1 (p=0.023). For those meeting criteria for a TSS greater than or equal to 20, mean WBC was 11.8 vs 9.5 x 109/L (p=0.04). For individuals meeting both criteria, mean WBC was 11.9 vs 9.5 x 109/L (p=0.034). The presence of peripheral blasts were significantly more common in patients with an individual worst symptom score greater than 5 (p=0.0364). Hemoglobin level was not significantly associated with symptom criteria for any cutoffs. CONCLUSION: Our analysis indicates that patients who would be treated based on symptom criteria are similar to patients who would be treated based on high risk features such as high DIPSS prognostic score, concerning blood count abnormalities (i.e., leukocytosis, thrombocytopenia, presence of peripheral blasts), and splenomegaly (particularly massive splenomegaly). Thrombosis history and age were not associated with criterion cutoff assignment, and it is notable that elderly age nor history of thrombosis alone would likely alter treatment choice other than anticoagulation. This data supports that JAK2 inhibitor treatment be strongly considered in patients meeting symptom based criteria. Disclosures Dueck: Bayer: Honoraria. Kiladjian:Novartis: Honoraria, Research Funding; AOP Orphan: Membership on an entity's Board of Directors or advisory committees, Research Funding. Zweegman:Celgene: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Takeda: Honoraria, Research Funding. Schouten:Sanofi: Consultancy; Novartis: Consultancy. Etienne:ARIAD: Speakers Bureau; Pfizer: Speakers Bureau; novartis: Consultancy, Speakers Bureau; BMS: Speakers Bureau. Harrison:Shire: Honoraria, Speakers Bureau; Gilead: Honoraria, Speakers Bureau; Baxaltra: Consultancy, Honoraria, Speakers Bureau; Incyte Corporation: Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria, Other: travel, accommodations, expenses, Research Funding, Speakers Bureau. Radia:Novartis: Honoraria; Pfizer: Honoraria. Cervantes:Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Baxalta: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AOP Orphan: Membership on an entity's Board of Directors or advisory committees. Vannucchi:Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Mesa:Promedior: Research Funding; Celgene: Research Funding; CTI: Research Funding; Gilead: Research Funding; Incyte: Research Funding; Galena: Consultancy; Ariad: Consultancy; Novartis: Consultancy.

Abstract Introduction: Guadecitabine (SGI-110) is a novel next-generation HMA administered as a small volume subcutaneous (SC) injection which results in extended decitabine exposure. Phase 2 studies have been conducted in TN-AML patients who were not candidates for intensive chemotherapy using two different doses and schedules of guadecitabine. We report here a comparative efficacy and safety analysis of the 5-day and 10-day regimens. Methods: TN-AML patients who were not candidates for intensive chemotherapy based on age (≥ 65 y), poor performance status (PS 2), comorbidities, or poor risk cytogenetics were enrolled in 2 separate treatment cohorts in the Phase 2 study. In the first cohort, patients were randomized (1:1) to either 60 mg/m2/d or 90 mg/m2/d on Days 1-5 (5-day regimen). In the second cohort, patients were treated with 60 mg/m2/d on Days 1-5 and Days 8-12 (10-day regimen) for up to 4 cycles, followed by 60 mg/m2/d Days 1-5 in subsequent cycles. Cycles were scheduled every 28 days for both regimes with dose reductions/delays allowed based on response and tolerability. Patients remained on treatment as long as they continued to benefit with no unacceptable toxicity. The primary endpoint was the composite Complete Response (CRc): Complete Response (CR) + CR with incomplete platelet recovery (CRp) + CR with incomplete neutrophil recovery (CRi) using modified International Working Group (IWG) criteria (Cheson et al, 2003). Secondary endpoints included overall survival (OS), and safety. Results: There was no difference in efficacy or safety between 60 and 90 mg/m2/d on the 5-day regimen (Yee et al, European Hematology Association meeting 2014, S647), so data are reported here for the two doses combined on the 5-day cohort. There were 51 patients treated in the 5-day regimen cohort and 52 treated with the 10-day regimen. There was no statistically significant difference in patient characteristics between the 2 regimens; median age 77.9 vs. 77.3 years ; male 59% vs. 65%; PS 2 or higher 35% vs. 40%; median BM blasts 40.0% vs. 49.5%; poor risk cytogenetics 46% vs. 43% for the 5-day and 10-day cohorts, respectively. Follow up of the 10-day cohort patients was shorter as it started after completion of enrolment of the 5-day cohort. The median follow up was 25.7 and 12.4 months and median number of cycles was 5 (range 1-26) and 3 (range 1-13) for the 5-day and 10-day cohorts, respectively. There was no significant difference in the primary efficacy endpoint, CRc, between the 2 regimens (p=0.43). CRc was achieved in 29/51 patients (57%) on the 5-day regimen (19 CR, 3 CRp, and 7 CRi) and in 25/52 patients (48%) on the 10-day regimen (16 CR, 5 CRp, and 4 CRi). Median OS was 10.5 and 8.7 months for the 5-day and 10-day cohorts, respectively (p=0.89). The 30, 60, and 90-day all-cause mortality rates were not statistically significant between the two cohorts: 5.9%, 15.7%, and 21.6% on the 5-day regimen and 1.9%, 17.3%, and 28.8% on the 10-day regimen. The most common Grade ≥3 AEs regardless of relationship to guadecitabine were: febrile neutropenia 59% vs. 60%, thrombocytopenia 47% vs. 38%, neutropenia 39% vs. 33%, anemia 27% vs. 19%, pneumonia 24% vs. 27%; and sepsis 12% vs. 19%, for the 5-day and 10-day cohorts respectively, none of which was statistically significant. Fifteen patients remain on treatment (5 from the 5-day cohort and 10 from the 10-day cohort). Conclusions: Guadecitabine is clinically active with a good safety profile in TN-AML patients not candidates for intensive chemotherapy. Unlike in relapsed/refractory AML, where the 10-day regimen of guadecitabine showed a trend toward improved efficacy (Roboz et al, Annals of Oncology 25 Supplement 4, 2014), there was no significant difference in either efficacy or safety between the 5-day and 10-day regimens in newly diagnosed AML patients. Guadecitabine 60 mg/m2/d SC Days 1-5 is currently being investigated in an 800-patient multicenter randomized phase 3 study in TN-AML patients unfit to receive intensive chemotherapy (ASTRAL-1 Phase 3 clinical trial: ClinicalTrials.gov reference NCT02348489). Disclosures Kropf: Teva Pharmaceuticals: Consultancy. O'Connell:Celgene: Speakers Bureau; Incyte: Membership on an entity's Board of Directors or advisory committees. Griffiths:Astex: Research Funding; Alexion Pharmaceuticals: Honoraria; Celgene: Honoraria. Rizzieri:Teva: Other: ad board, Speakers Bureau; Celgene: Other: ad board, Speakers Bureau. Stock:Gilead: Membership on an entity's Board of Directors or advisory committees. Savona:Karyopharm: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees. Rosenblat:Astex Pharmaceuticals, Inc.: Research Funding. Berdeja:Celgene: Research Funding; Onyx: Research Funding; BMS: Research Funding; Abbvie: Research Funding; Array: Research Funding; Curis: Research Funding; Acetylon: Research Funding; MEI: Research Funding; Janssen: Research Funding; Novartis: Research Funding; Takeda: Research Funding. Wilson:Astex Pharmaceuticals, Inc.: Employment. Lowder:Astex Pharmaceuticals, Inc.: Employment. Taverna:Astex Pharmaceuticals, Inc.: Employment. Hao:Astex Pharmaceuticals, Inc.: Employment. Azab:Astex Pharmaceuticals, Inc.: Employment. Issa:Janssen: Consultancy; Astex Pharmaceuticals, Inc.: Consultancy.

Abstract Background: Cytoreductive therapy with hydroxyurea (HU) has been considered first line therapy for patients with high risk polycythemia vera (PV) and essential thrombocythemia (ET) since the results of the PVSG-08 trial demonstrated thrombotic risk reduction (Fruchtman SM et al 1997) for PV and PT1 for ET (Harrison CN et al 2005). Although HU is well tolerated by most patients and has been shown to reduce thrombotic risk in this setting, concern regarding the leukemogenic potential of this oral ribonucleotide reductase inhibitor balanced by the observation of molecular responses with interferon-α (IFN-α) led us to compare the clinical response and tolerability of pegIFN-α (PEG) and HU in a global, randomized, phase III trial. Methods : MPD-RC 112 trial (NCT01258856) enrolled patients with high risk (age >60 years, history of thrombosis, extreme thrombocytosis, symptomatic splenomegaly, uncontrolled cardiovascular risk factors), newly diagnosed (<5 years), WHO defined ET/PV that were treatment naïve (HU <3 months) and randomized (1:1) to PEG or HU. The primary endpoint was complete hematologic response (CHR) rate by European LeukemiaNet (ELN) criteria between the arms after 12 months of therapy. A planned interim analysis based on intent-to-treat with testing boundaries for efficacy and futility was conducted after 75 patients were on study for 12 months. Response assessment by ELN criteria were conducted by blinded review by 4 investigators (JM, RAM, AY, RH). Intent-to-treat analysis was conducted for efficacy endpoints (HU n=39; PEG n=36). Safety analysis included all patients who received treatment (HU n=36; PEG n=36). Results: Patients: The MPD-RC 112 trial involved 24 centers in 6 countries; enrollment began 09/2011 and concluded 7/2016 prior to full accrual due to study drug availability with 168 patients enrolled (Table 1 for 75 patients in the interim analysis). There was no imbalance between arms with respect to history of thrombosis, erythromelalgia, diabetes, hypertension, but age was significantly older on HU. This remained true when analyzing by ET/PV disease strata with the exception of diabetes which was slightly imbalanced within the PV cohort (HU 5/23, 22%; PEG 0/21, 0%; p<0.05). Response: CHR and PHR were observed in 13 (33%) and 14 (36%) patients for an overall response rate (ORR) of 69% (27/39) for HU, and 10 (28%) and 19 (53%) for an ORR of 81% (29/36) for PEG (CHR comparison p=0.60 based on z-test which did not cross either testing boundary). 10 patients randomized to HU were not evaluable for 12-month response due to never initiating treatment (n=3) or early study discontinuation for AEs (n=1), patient withdrawal (n=5), or treatment non-compliance (n=1). 3 patients were not evaluable for response on PEG due to early study discontinuation for AEs (n=1), physician decision (n=1), or patient withdrawal (n=1). Excluding patients who never initiated treatment did not impact the primary endpoint comparison (HU 13/36, 36%; PEG 10/36, 28%; p=0.45). For ET, CHR and PHR were observed in 7 (44%) and 4 (25%) patient on HU, and 6 (40%) and 6 (40%) for PEG (CHR comparison p=0.83). For PV, CHR and PHR were observed in 6 (26%) and 10 (44%) patients on HU, and 4 (19%) and 13 (62%) for PEG (CHR comparison p=0.58). Normalization of spleen by palpation at 12 months was seen in 2/7 (29%) and 5/7 (71%) of the HU and PEG treated patients with palpable spleen at baseline, respectively. Among 38 PV patients, rate of phlebotomy use at 12 months was 0/18 (0%) vs 5/20 (20%) on HU and PEG (p=0.02). From baseline to best score through 12 months, 9/28 (32%) and 12/34 (35%) patients with data on HU and PEG, respectively, had a ≥50% reduction in MPN-SAF Total Symptom Score (p=0.79). Toxicity: No Grade 4 AEs occurred in either treatment arm. Overall, Grade 3 AEs occurred in 5/36 (14%) HU patients and 16/36 (44%) PEG patients (Grade 3 hematologic: 4/36 [11%] HU vs 8/36 [22%] PEG; Grade 3 non-hematologic: 5/36 [14%] HU vs 16/36 [44%] PEG). See Table 2 for Grade 3 AEs regardless of attribution occurring in >10% of patients in either arm. Conclusions: This interim analysis does not show a clear difference in primary endpoint of CHR between HU and PEG. A comparative analysis of the quality of life and symptom burden will provide further insight into the tolerability of these agents (Mesa et al ASH 2016). The final results of this pivotal trial will provide necessary data required to firmly establish the optimal first line therapy for patients with high risk ET/PV. Disclosures Mascarenhas: CTI Biopharma: Research Funding; Janssen: Research Funding; Promedior: Research Funding; Roche: Research Funding; Novartis: Other: DSMB , Research Funding; Incyte: Other: Clinical Trial Steereing Committee, Research Funding. Mesa:Celgene: Research Funding; Promedior: Research Funding; CTI: Research Funding; Gilead: Research Funding; Incyte: Research Funding; Galena: Consultancy; Ariad: Consultancy; Novartis: Consultancy. Yacoub:Alexion: Honoraria; Seattle Genetics: Consultancy, Honoraria, Speakers Bureau; Incyte: Consultancy, Honoraria, Speakers Bureau. Harrison:Baxaltra: Consultancy, Honoraria, Speakers Bureau; Incyte Corporation: Honoraria, Speakers Bureau; Gilead: Honoraria, Speakers Bureau; Shire: Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria, Other: travel, accommodations, expenses, Research Funding, Speakers Bureau. McMullin:Novartis: Honoraria, Speakers Bureau. Vannucchi:Novartis: Honoraria, Speakers Bureau. Kiladjian:Novartis: Honoraria, Research Funding; AOP Orphan: Membership on an entity's Board of Directors or advisory committees, Research Funding. Mead:Novartis: Honoraria, Research Funding, Speakers Bureau. Kessler:Incyte: Honoraria. Ritchie:Celgene: Consultancy, Other: Travel, Accomodations, Expenses, Speakers Bureau; Incyte: Consultancy, Speakers Bureau; Novartis: Consultancy, Other: Travel, Accommodations, Expenses, Research Funding, Speakers Bureau; Ariad: Speakers Bureau; Pfizer: Consultancy, Research Funding; Astellas Pharma: Research Funding; Bristol-Meyers Squibb: Research Funding; NS Pharma: Research Funding. Schlenk:Amgen: Research Funding; Pfizer: Honoraria, Research Funding.

Abstract Background Polycythemia vera (PV) is a clonal myeloproliferative disorder characterized by erythrocytosis, splenomegaly and a frequently burdensome symptom profile. Despite current guidelines of aspirin, phlebotomy, and selective cytoreduction, many patients have inadequately controlled PV-related symptoms and/or disease features. We performed a comparison of PV symptom burden/disease feature phenotypes to understand unmet needs in current medical management. Methods Data was collected prospectively amongst an international cohort of PV patients including symptom burden, demographics, and disease features. Subgroups were identified who had previously failed hydroxyurea (PV-HU), required ongoing phlebotomy (PV-P), had palpable splenomegaly (PV-S), or had all 3 features (PV-HUPS). Control groups were derived from the remaining PV patients lacking the specified subgroup trait; patients in whom the trait status was unknown were excluded from each respective control group. All participants completed the MPN specific symptom burden questionnaire (MPN-SAF TSS (MPN-10 – Table 1)) and had no prior history of splenectomy. Surveyed symptoms on the MPN-10 included the patient's perceptions of common MPN-related symptoms and overall quality of life (QOL) on a 0 (absent) to 10 (worst imaginable) scale. PV risk scores were calculated using the 2013 criteria (Leukemia 2013). Comparison of symptoms between groups employed t-tests. Results Patient Demographics and Disease Features Between Phenotypic Groups A total of 1334 PV patients completed the MPN-10, and were assigned to categories of PV-HU (499 [37%]), PV-P (646 [48%]), PV-S (369, [28%]), and PV-HUPS (148 [12%]). The demographics between these groups were similar (comparable age (median range 60-63), PV risk scores (mean risk range: Low 16.4-23.7%; Intermediate 31.4%-36.6%; High 42.8%-47%). Mean hemoglobin was similar among PV subgroups (range 14.4-14.9); PV-HUPS had a higher mean WBC count (20.3 g/dL vs. 8.8-11.8 g/dL) and platelet count (703.5 x 10(9)/L vs. 327.5-462.8 x 10(9)/L), and disease duration (11.5 years vs. 6.4-8.8 years). Prior thrombosis was most common in PV-S patients (28.5% vs. 21.8-25.2%) and prior hemorrhage was most common in PV-HUPS patients (23.8% vs. 13.7-15.8%). Symptom Burden The MPN-10 scores of each problematic PV phenotype (HU, P, S, HUPS) were compared to the remainder of the PV cohort lacking the trait (PV-control; Table 1). Both individual symptom scores and TSS were highest for PV-HUPS patients (mean TSS 32.5 vs. 27.7-29.2). All problematic PV subgroups demonstrated significant differences for individual symptoms and TSS compared to PV-control. Comparing "problematic" subgroup responses, PV-HU patients described more inactivity whereas PV-S patients described more early satiety and pruritus. No statistical differences were noted in PV-HU, PV-P and PV-HUPS patient responses to MPN-10 items of "fever" and "weight loss". Discussion PV patients who have either failed HU, are undergoing phlebotomy and/or have splenomegaly exhibit moderate to severe symptomatology and demonstrate unmet medical need for management. As evidenced in this study, considerable overlap in symptomatology exists in PV-HU, PV-P, PV-S and PV-HUPS. Current randomized trials of JAK inhibitors have demonstrated benefits in a PV-HUPS phenotype. This data suggests that PV patients with any evidence of inadequate control (PV-HU, P, or S) have similarly unmet needs and may be candidates for clinical trials, intensification of medical therapy or perhaps JAK inhibitor therapy. Disclosures Kiladjian: Shire Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees. Zweegman:Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Millennium: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen-Cilag: Membership on an entity's Board of Directors or advisory committees, Research Funding. Besses:Shire Pharmaceuticals: honoraria for educational lectures Other. Birgegard:Shire Pharmaceuticals: Consultancy, Honoraria, Research Funding. Etienne:Novartis, BMS, Pfizer, Ariad: Honoraria. Roy:Merck: Peg-Interferon provided for academic clinical trial in CML Other. te Boekhorst:Novartis: Consultancy. Griesshammer:Novartis: Honoraria; Shire: Honoraria; Sanofi: Honoraria; Amgen: Honoraria; Roche: Honoraria. Mesa:Incyte Corporation, CTI, NPS Pharma, Inc., Gilead Science Inc., Celgene: Research Funding.

Yacoub et al report excellent responses to pegylated interferon alfa-2a in patients with hydroxyurea-resistant/intolerant polycythemia vera or essential thrombocythemia.