Passamonti, Francesco

Abstract Background In the recent International Prognostic Score for Thrombosis in essential thrombocythemia (IPSET-thrombosis), age and history of thrombosis were confirmed as independent risk factors for future thrombosis and the study also identified independent prothrombotic role for cardiovascular (CV) risk factors and JAK2 V617F mutation (Barbui et al. Blood 2012). Methods In the current study, we re-analyzed the original IPSET-thrombosis data in 1019 patients with WHO-defined ET in whom JAK2 mutational status was available, in order to quantify the individual contributions of JAK2 mutations and CV risk factors in conventionally-assigned low and high risk ET, as well as in age- versus thrombosis-defined high risk status. Results After a median follow-up of 6.8 and 5.0 years in conventionally-assigned low- and high-risk patients, respectively, the overall annual rate of total thrombosis (108 events) in conventionally-assigned low- and high-risk patients was 1.11%-pt/y (CI 0.81-1.52) and 2.46%-pt/y (CI 1.94-3.11) respectively (p=0.001), and the difference was mainly due to a higher frequency of arterial thrombosis in high-risk patients (p<0.001).The influence of JAK2 mutational status and CV-risk factors on the rate of thrombosis in conventionally assigned low- and high-risk groups is presented in the table. Table 1. Additional risk factors N (%) Event Rate % pts/yr (95% CI) P-value P-value P-value trend Low risk 506 (50) 39 1.11 (0.81-1.52) None 200 (40) 7 0.44 (0.21-0.92) ref Cardiovascular risk factor 36 (7) 3 1.05 (0.34-3.25) 0.220 0.227 JAK2V617F 213 (43) 21 1.59 (1.04-2.44) 0.001 0.217 Both 52 (10) 8 2.57 (1.29-5.15) <0.001 ref <0.001 High risk 513 (50) 69 2.46 (1.94-3.11) None 111 (22) 10 1.44 (0.78-2.68) ref Cardiovascular risk factor 44 (9) 4 1.64 (0.62-4.37) 0.909 0.067 JAK2V617F 222 (43) 30 2.36 (1.65-3.38) 0.168 0.082 Both 136 (27) 25 4.17 (2.82-6.17) 0.011 ref 0.005 The number of major arterial and venous thrombosis was reported as rates per 100 patient-years and the difference among groups was assessed by Mantel Cox log-rank test i) Conventionally-assigned low-risk group. Amongst 506 patients, 200 (40%) displayed neither JAK2 mutation nor CV risk factors and their annual rate of thrombosis was 0.44%, as opposed to 1.05% in the presence of CV risk factors (P=NS), 1.59% in the presence of JAK2 mutation (p=0.001) and 2.57% in the presence of both CV risk factors and JAK2 mutation (P<0.001). There was no significant difference when low-risk patients with both JAK2 mutation and CV risk factors were compared with either those with CV risk factors only (p=0.227) or those with JAK2 mutation only (p=0.217). ii) Conventionally assigned high-risk group: The absence or presence of one or both of the aforementioned additional risk factors for thrombosis were documented in 111 (22%), 44 (9%), 222 (43%) and 136 (27%) patients, respectively, with corresponding annual rates of thrombosis at 1.44%, 1.64%, 2.36% and 4.17% (Table). High-risk patients with both risk factors had a significantly higher risk of thrombosis compared to their counterparts with the absence of JAK2 mutations and CV risk factors (p=0.011). Additional analysis revealed limited enhancement of thrombosis risk by either JAK2 mutations or CV risk factors or both in patients whose high-risk status was defined by the presence of thrombosis history, regardless of age (P=NS). In contrast, the presence of JAK2 mutations, with or without CV risk factors, might have affected thrombosis risk in patients where high-risk status was defined by age alone (p=0.05). Conclusions The current study suggests the possibility of considering four risk categories in ET: "very low risk" group (age ≤60 years and without thrombosis history, JAK2 mutations or CV risk factors); "low risk" (age ≤60 years and without thrombosis history but with JAK2 mutations or CV risk factors); "intermediate risk" (age>60 years but without thrombosis history or JAK2 mutations); and "high risk" (thrombosis history at any age or JAK2 -mutated patients who are older than 60 years of age). Treatment recommendations for each one of the above-mentioned new risk categories should be examined in the context of prospective controlled studies. Disclosures Barbui: Novartis: Speakers Bureau. Vannucchi:Novartis Pharmaceuticals Corporation: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Shire: Speakers Bureau; Baxalta: Membership on an entity's Board of Directors or advisory committees. Buxhofer-Ausch:AOP Orphan: Research Funding. De Stefano:Novartis: Research Funding, Speakers Bureau; Janssen Cilag: Research Funding; Shire: Speakers Bureau; GlaxoSmithKline: Speakers Bureau; Bruno Farmaceutici: Research Funding; Roche: Research Funding; Amgen: Speakers Bureau; Celgene: Speakers Bureau. Gisslinger:Janssen Cilag: Honoraria, Speakers Bureau; AOP ORPHAN: Consultancy, Honoraria, Research Funding, Speakers Bureau; Geron: Consultancy; Sanofi Aventis: Consultancy; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Novartis: Honoraria, Research Funding, Speakers Bureau.

Abstract Abstract 1909 Poster Board I-932 Background: The International Prognostic Scoring System (IPSS) for primary myelofibrosis (PMF) utilizes five independent predictors of inferior survival; of these, a hemoglobin level <10 g/dL has the highest impact on survival (Cervantes et al. Blood 2009;113:2895). In the current study, we examined the additional prognostic impact of transfusion need at diagnosis or becoming transfusion-dependent in the first year of diagnosis. These events were also correlated with JAK2 or TET2 mutational status. Methods: Patients were selected from the Mayo Clinic PMF database based on availability of bone marrow histology and IPSS-relevant information at diagnosis and follow-up transfusion history at one year from diagnosis. WHO criteria were used for PMF diagnosis. Patients who underwent allogeneic hematopoietic cell transplantation were censored at time of transplant. Patient records were updated in July, 2009. Survival curves were constructed using the Kaplan-Meier method and compared by the log-rank test. Multivariable survival was analysed using Cox regression model. Results: A consecutive cohort of 254 patients was studied (median age 59 years; range 28-87; 159 males). IPSS risk category was low, intermediate (int)-1, int-2 and high in 75, 71, 62 and 46 patients, respectively. JAK2V617F was present in 118 (62%) of 192 patients and TET2 mutations in 6 (13%) of 45 patients evaluated. Transfusion need at diagnosis was documented in 62 patients whereas an additional 22 patients became transfusion-dependent during the first year of their diagnosis. The remaining 170 patients remained transfusion-independent for at least one year post-diagnosis. To date, 139 patients have died. In patients who are alive, median follow-up was 5.3 years. Median survivals in IPSS high, Int-2, Int-1 and low risk patients were, 3, 3.9, 6.8 and 12.8 years, respectively (p<0.0001). Median survival for patients requiring transfusions at diagnosis was similar to that of patients who became transfusion-dependent in their first year of diagnosis, and both were significantly shorter than the median survival seen in patients who remained transfusion-free during the first year post-diagnosis: 2.9, 2.2 and 9.7 years, respectively (p<0.0001; figure). Multivariable analysis confirmed the IPSS-independent prognostic value of transfusion status-based risk stratification. Neither JAK2 nor TET2 mutational status correlated with transfusion need. Conclusions: In PMF, becoming transfusion-dependent in the first year of diagnosis is prognostically as detrimental as requiring transfusions at initial presentation. These events are not affected by JAK2 or TET2 mutational status and confer an IPSS-independent adverse prognosis. The ability to identify Int-1 risk patients with shortened survival (Figure) holds major treatment implications. Disclosures: No relevant conflicts of interest to declare.

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 Background : Polycythemia vera (PV) is a myeloproliferative neoplasm driven by JAK/STAT activation and is associated with erythrocytosis and a broad symptom burden that may negatively impact patient quality of life (QoL). Hydroxyurea (HU) is often used as first-line therapy for high-risk patients but may not effectively control or reduce symptom burden. RESPONSE is a phase III trial comparing ruxolitinib (RUX) with best available therapy (BAT) in patients with PV who were intolerant of or resistant to HU according to modified European LeukemiaNet (ELN) criteria. The primary study endpoint (a composite of hematocrit control and ≥35% spleen volume reduction at Week 32) was achieved by 21% of patients in the RUX arm vs 1% in the BAT arm (P<0.0001); 77% of patients in the RUX arm achieved at least one component of the primary endpoint. The current analysis was conducted to evaluate the effect of RUX on PV-related symptoms and QoL measures in the RESPONSE trial. Methods : Patients with PV aged ≥18 years, resistant to or intolerant of HU (modified ELN criteria) with splenomegaly, and who required phlebotomy for hematocrit control were randomized 1:1 to receive open-label RUX 10 mg twice daily (BID) or BAT (administered based on investigator judgment). Dose adjustments were permitted (RUX, 5-mg BID increments [25 mg BID max]; BAT was adjusted per investigator judgment). Objectives of this analysis included assessment of improvement in symptom burden as assessed by patient-reported outcomes using the 14-item modified Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF), the Pruritus Symptom Impact Scale (PSIS), the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30), and the Patient Global Impression of Change. The 14-item MPN-SAF (graded from 0 [absent] to 10 [worst imaginable]) comprised symptoms related to cytokines (tiredness, itching, muscle ache, night sweats, and sweats while awake), hyperviscosity (vision problems, dizziness, concentration problems, headache, numbness/tingling, ringing in ears, and skin redness), and splenomegaly (abdominal discomfort and early satiety). Changes in total symptom score (TSS; maximum score = 140) and individual symptom scores from baseline to Week 32 were summarized by treatment group. For the EORTC QLQ-C30 Global Health Status/QOL score, the percentage of patients with a minimally important difference (MID) from baseline (10-point change) at Week 32 was summarized. Results : Overall, 222 patients were randomized (RUX, 110; BAT, 112). Median age (range) was similar between arms (RUX, 62.0 [34.0–90.0]; BAT, 60.0 [33.0–84.0]); the RUX and BAT arms were 60% and 71% male, respectively. At Week 32, a higher proportion of patients in the RUX vs the BAT arms had a ≥50% improvement in MPN-SAF TSS (49% vs 5%, respectively) and MPN-SAF symptom cluster scores (cytokine, 64% vs 11%; hyperviscosity, 37% vs 13%; splenomegaly, 62% vs 17%). Median percentage changes in individual symptom scores are presented in the Table. Mean changes from baseline at Week 32 on the 5 items of the PSIS indicated that the severity of pruritus and its interference on daily life improved with RUX (range, −1.5 to −2.2) and was unchanged/worsened with BAT (range, −0.1 to 0.3). Treatment with RUX vs BAT was associated with improved mean changes from baseline at Week 32 on EORTC QLQ-C30 symptom subscales, functional subscales, and Global Health Status/QOL (Table); 46% of RUX patients versus 10% of BAT patients achieved an MID in Global Health Status/QOL (Figure). At Week 32, RUX patients were more likely to rate their global impression of symptom changes as “very much improved” or “much improved” (67%) vs BAT patients (13%). Conclusion : In patients with PV who were resistant to or intolerant of HU, treatment with RUX was associated with greater and clinically meaningful improvements in PV-related symptom burden and QoL measures compared with BAT. Figure 1 Figure 1. Figure 2 Figure 2. Disclosures Mesa: Incyte Corporation: Research Funding; CTI: Research Funding; Gilead: Research Funding; Genentech: Research Funding; Eli Lilly: Research Funding; Promedior: Research Funding; NS Pharma: Research Funding; Sanofi: Research Funding; Celgene: Research Funding. Off Label Use: Ruxolitinib is a JAK1/JAK2 inhibitor approved for the treatment of patients with intermediate or high-risk myelofibrosis, including primary myelofibrosis, post polycythemia vera myelofibrosis, and post-essential thrombocythemia myelofibrosis. Verstovsek:Incyte Corporation: Research Funding. Kiladjian:Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Masszi:Novartis Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees. Durrant:Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Harrison:Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. He:Incyte Corporation: Employment, Equity Ownership. Jones:Incyte Corporation: Employment, Equity Ownership. Parasuraman:Incyte Corporation: Employment, Equity Ownership. Li:Novartis Pharmaceuticals: Employment, Equity Ownership. Côté:Novartis Pharmaceuticals: Employment, Equity Ownership. Habr:Novartis Pharmaceuticals: Employment, Equity Ownership. Vannucchi:Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, 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 Abstract 1729 Background: Primary myelofibrosis (PMF) is a myeloproliferative neoplasm whose survival at diagnosis is predicted by the International Prognostic Scoring System (IPSS), which is based on the presence of the following five risk factors: age greater than 65 years, presence of constitutional symptoms, hemoglobin level below 10 g/dL, leukocyte count greater than 25 ×109/L, and circulating blast cells 1% or greater (Cervantes et al, Blood 2009). To allow dynamic prognostication at any time during follow up, we further developed the Dynamic International Prognostic Scoring System (DIPSS), based on the same IPSS-factors, but with different score values (one point for each risk factor, two points for acquisition of anemia) and with a distinct score model (low risk, LR, 0 points; intermediate-1 risk, Int-1R, 1–2 points; intermediate-2 risk, Int-2R, 3–4 points; high risk, HR, 5–6 points) (Passamonti et al, Blood 2010). The DIPSS model was also efficient in the prediction of acute myeloid leukemia (AML) evolution (Passamonti et al, Blood 2010) and in the assessment of survival and non-relapse mortality after allogeneic hematopoietic stem cell transplantation (Scott et al, Blood 2012). Aim: The aim of the present study is to update outcome data of PMF patients included in the original series used to generate the DIPSS model and to assess the DIPSS prediction of survival in PMF patients with a longer follow up. The Institutional Review Board approved the study, and the procedures followed were in accordance with the Declaration of Helsinki. Patients and methods: This study was performed on 520 of 525 regularly followed DIPSS-PMF patients, as five patients have been lost to follow up after the original publication. Results: Updated median follow up was of 4.1 years (range, 0.1–30.1). At the time of analysis 326 (63%) patients died, of whom 194 due to known causes: 69 AML, 16 non-AML disease progression, 21 bleeding, 17 thrombosis, 33 infections, 38 other. Median survival was 6 years (95% CI: 5.1–6.7). DIPSS stratification allowed different survivals in PMF patients even with a longer follow-up (Figure 1). Hence, to assess the time to DIPSS-category progression, we evaluated the median time spent within each risk group. This estimate revealed that the median time spent in each risk category was: 4.9 years in LR (range, 0–26.7), 2.1 years in Int-1R (range, 0–18.7), 1.7 years in Int-2R (range, 0–13.4), and 0.74 years in HR (range, 0–13.7). To investigate the prognostic role of the DIPSS score on survival, we analyzed the score as a categorical time-dependent covariate in a Cox survival regression model: the hazard ratio of shifting category from LR to Int-1R was 5.0 (95% CI: 2.4–10.6; P <0.001), it was 3.6 when shifting from Int-1R to Int-2R (95% CI: 2.6–4.9; P <0.001), and 2.7 (95% CI: 2.0–3.6; P <0.001) from Int-2R to HR. Conclusion: The updated analysis shows that the DIPSS model continues to predict survival in patients with PMF. Disclosures: No relevant conflicts of interest to declare.

Abstract BACKGROUND: Symptom burden in essential thrombocythemia (ET) and polycythemia vera (PV) is severe even among individuals with low risk disease (Blood 2012. 12;123(24):3803-10). New therapies exist which alleviate the severe symptom burden and reduce splenomegaly in ET and PV patients (N Engl J Med 2015; 372:426-435). This analysis is the first to date to evaluate thresholds at which symptom-based treatment can be considered for ET and PV patients who are intolerant or resistant to hydroxyurea (HU). METHODS: Patient demographics, symptom burden, and disease traits were collected from ET and PV patients at a single time point during therapy. The MPN-10 total symptom score (TSS, JCO 2012;30(33)4098-103) was utilized to assess symptom burden. Symptom criteria models were determined as previously described among a population of MF patients (Scherber et. al. EHA 2016: a2250). Cutoffs were then evaluated in a cohort of ET and PV patients to assess for utility as a symptom model among this population. RESULTS: Demographics and symptom burden: 838 PV and 867 ET patients with previous hydroxyurea therapy were included in this analysis. Patients were of mean age (54.9 years ET, 64.0 years PV) and gender (69.2% female ET, 55.7% female). Mean disease duration was 6.0 years for ET and 7.3 years for PV.Among ET and PV patients, 15.0% and 24.2% had prior thrombosis respectively. In evaluating prognostic risk, ET patients tended to be low (45.5%) or intermediate risk (42.9%) with only a minority of patient meeting criteria forhigh risk disease (11.6%). Laboratory findings: ET patients had a mean platelet value of 598.7x 109/L(SD=283.4). Among PV patients, mean hematocrit was 45.8% (SD=8.1) and 42.6% of patients had a hematocrit of greater than 45%. White blood cell count was normal between the two groups (ET mean 8.3 x 109/L, PV mean 9.0 x 109/L). Symptoms: Mean worst symptom severity was 6.4 out of 10 (SD=2.7). Among ET patients, worst symptom was most frequently fatigue (32.7%, mean 5.0/10, SD=3.1, overall prevalence 88%) followed by night sweats (13.6%, mean 2.0/10, SD=3.0, overall prevalence 53%) and concentration difficulties (8.6%, mean 3.1/10, SD=3.0, overall prevalence 68%). For PV, worst individual symptom items were most frequently fatigue (29.2%, mean 5.2/10, SD=3.0, overall prevalence 91%), pruritus (14.1%, mean 3.2/10, SD=3.2, overall prevalence 69%), and night sweats (12.8%, mean 2.5/10, SD=3.0, overall prevalence 57%). Cutoff Scoring: 47.0% of ET patients fit criteria for TSSgreater than to equal to 20; 59.0%% had a single itemgreater than 5; and 45.7% had both a TSS greater than or equal to 20 and a single item greater than 5. Among PV participants, 54.5% had aTSS greater than to equal to 20; 66.1% had a single itemgreater than 5; and 51.5% had both a TSS greater than or equal to 20 and a single item greater than 5. Each scoring method was significantly associated with individual item scores (Table 1). Prognostic scoring was not significantly associated with any of the symptom cutoffs evaluated. Correlations: Among ET patients, a prior history of thrombosis was significantly associated with having a worst symptom item greater than 5 (p=0.043). ET patients with lower hemoglobin were significantly more likely to meet criteria for a MPN-10 score greater than or equal to 20 or to meet combined criteria for a MPN-10 greater than or equal to 20 and single worst item greater than 5 (for both p=0.01 or less). For PV, lower hematocrit levels were significantly associated with having an individual worst symptom score of greater than 5 (44.9% versus 46.7%, p=0.0376). CONCLUSION: Assessment of ET and PV symptoms, now measurable through standardized and practical instruments such as the MPN-10, is an integral part of determining therapeutic impact of newer therapies in both clinical practice and trial settings. In our modeling, patients with severe symptom burden profiles are well represented by utilizing cutoff criteria including aworst individual symptom item of greater than 5 out of 10, an MPN-10 score of greater than or equal to 20, or combined criteria of both cutoffs. These cutoffs can be considered when determiningwhich HU intolerant or resistant patients would most benefit fromsymptom orientedtreatment. Disclosures Kiladjian: AOP Orphan: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Research Funding. Schouten:Novartis: Consultancy; Sanofi: Consultancy. Etienne:BMS: Speakers Bureau; ARIAD: Speakers Bureau; Pfizer: Speakers Bureau; novartis: Consultancy, Speakers Bureau. Harrison:Incyte Corporation: Honoraria, Speakers Bureau; Shire: Honoraria, Speakers Bureau; Gilead: Honoraria, Speakers Bureau; Baxaltra: Consultancy, Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria, Other: travel, accommodations, expenses, Research Funding, Speakers Bureau. Radia:Pfizer: Honoraria; Novartis: Honoraria. Cervantes:AOP Orphan: Membership on an entity's Board of Directors or advisory committees; Baxalta: 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. 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 Background : Polycythemia vera (PV) is a myeloproliferative neoplasm characterized by erythrocytosis, and in many cases leukocytosis and thrombocytosis. PV is driven by activating mutations in the JAK/STAT pathway, primarily JAK2V617F. For high-risk patients, a commonly used first-line therapy is hydroxyurea (HU); however, a subgroup of patients become intolerant of or resistant to HU. The phase 3 RESPONSE trial compared ruxolitinib (RUX) and best available therapy (BAT) in patients with PV who were intolerant of or resistant to HU (modified European LeukemiaNet criteria). Patients randomized in the BAT arm were permitted to cross over to receive RUX from Week 32 of the study. The results of the primary analysis comparing RUX to BAT prior to crossover have been reported, in which RUX was superior to BAT in achieving hematocrit control, reductions in spleen volume, and improvements in PV-related symptoms. This current analysis was conducted to evaluate the efficacy of RUX treatment in patients who crossed over from BAT relative to their original BAT treatment and relative to those originally randomized to RUX. Methods : Enrollment criteria included PV diagnosis, age ≥18 years, resistance to or intolerance of HU, splenomegaly, and phlebotomy requirement to control hematocrit. Patients were randomized 1:1 to receive open-label RUX 10 mg BID or BAT administered based on investigator judgment. BAT may have included HU, interferon/pegylated interferon, pipobroman, anagrelide, immunomodulators (eg, lenalidomide or thalidomide), or no medication. The protocol allowed for dose modifications (RUX, 5-mg BID increments [25 mg BID max]; BAT was adjusted per investigator judgment). Patients in the BAT group could cross over to RUX from Week 32 if they had not met the primary endpoint, or after Week 32 due to protocol-defined disease progression. The primary study endpoint was a composite of hematocrit control and a ≥35% reduction in spleen size at Week 32. Hematocrit was assessed at screening, every 2 weeks from Day 1 to Week 12, followed by every 4 weeks until Week 32, and 2, 4, 6, 8, 16, 24, and 32 weeks following crossover. Spleen volume was assessed by magnetic resonance imaging at screening and study Weeks 16, 32, 48, 64, 80 and every 32 weeks thereafter. The number of phlebotomy procedures was evaluated over time in each group. Results : A total of 110 patients were randomized to RUX and 112 to BAT; study discontinuation by Week 32 (before crossover was permitted) was 11% in both groups. However, most patients in the BAT arm crossed over to receive RUX treatment immediately after the Week 32 visit (84% between Weeks 32 and 48); only 3% of patients remained in the BAT arm compared with 85% in the RUX arm at the time of the data analysis (median 81-week follow-up). With up to 32 weeks on BAT therapy, 25% of patients in this group did not require a phlebotomy; in contrast, with up to 32 weeks on RUX, 79% of patients after crossover and 74% of patients initially randomized to RUX did not require phlebotomy. The number of phlebotomy procedures adjusted for 100 patient-years during BAT therapy was 196.8 vs 38.5 after crossover to RUX and 34.1 on randomized RUX treatment. Reduction in spleen volume from baseline at any visit occurred in 49% of patients receiving BAT, vs 73% of patients after crossover to RUX and 88% of patients initially randomized to RUX. The proportion of patients achieving at least a 35% reduction in spleen volume (best percentage change) was 1.8% during BAT treatment vs 38.5% after crossover to RUX and 60.0% during randomized RUX treatment. Conclusion : Treatment with RUX after crossover from BAT resulted in improved clinical outcomes compared with original BAT treatment. These findings support the primary RESPONSE results and further validate the efficacy of RUX in this patient population. Disclosures Kiladjian: Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Off Label Use: Ruxolitinib is a JAK1/JAK2 inhibitor approved for the treatment of patients with intermediate or high-risk myelofibrosis, including primary myelofibrosis, post polycythemia vera myelofibrosis, and post-essential thrombocythemia myelofibrosis. Vannucchi:Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Masszi:Novartis Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees. Durrant:Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Harrison:Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Mesa:Incyte Corporation: Research Funding; CTI: Research Funding; Gilead: Research Funding; Genentech: Research Funding; Eli Lilly: Research Funding; Promedior: Research Funding; NS Pharma: Research Funding; Sanofi: Research Funding; Celgene: Research Funding. Jones:Incyte Corporation: Employment, Equity Ownership. He:Incyte Corporation: Employment, Equity Ownership. Li:Novartis Pharmaceuticals : Employment, Equity Ownership. Habr:Novartis Pharmaceuticals: Employment, Equity Ownership. Verstovsek:Incyte Corporation: Research Funding.