Mesa, Ruben A.

Abstract Background: Patients diagnosed with cancer experience a significant influx of health care information while continuing to demonstrate understanding deficit regarding their disease and health. This knowledge deficit can negatively impact a patient’s acute and long term health care experience. By identifying patient information deficits and needs, health care providers may be better able to provide targeted education to patients and families. Aims: The aim of this study is to evaluate the impact of a patient centered cancer symposium on knowledge level, reported symptom burden, and desired information from a broad population of cancer patients. Methods: Surveys were distributed to the attendees of the third annual Mayo Clinic “Living with Cancer” patient symposium in January 2014. While 700 individuals registered for the event, only individuals with a past or present cancer diagnosis were asked to participate. Surveys included demographic data in addition to a questionnaire evaluating disease comprehension, symptom burden, desired information and desired role in the health care decision making process. Results: 75 patients completed the pre-intervention and post-intervention survey. There were slightly more female participants (60.2%). Disease types included 40% hematologic malignancies, 27% breast cancer, 20% prostate cancer and 13% other. The majority of patients were greater than 3 years from cancer diagnosis (62%). Baseline Patient Understanding: Most respondents reported understanding their disease quite a bit (54%) or very much (30%). Respondents reported the majority of their knowledge regarding their disease came from their oncologist (56%), oncology nurse (24%), previous symposiums (22%), or the internet (15%). Most respondents reported “quite a bit” or greater comprehension of screening tests (75%), monitoring disease response to treatment (70%), monitoring disease recurrence (70%), treatment options (67%) and treatment side effects (73%). There was no consensus among participants regarding understanding or limiting risk factors, symptoms associated with disease relapse, fatigue and pain management, navigating the health care system, financial considerations, or confidence in their primary care physician’s involvement in their cancer or post-cancer care. A large proportion of attendees reported “quite a bit” or greater desire for increased information/understanding regarding their disease (83%), risk factors (83%), nutrition (80%), screening tests (69%), and management of fatigue (69%) and stress (68%). Knowledge Improvement Durable at 3 months: There was improvement in 18 of 20 areas of self-reported knowledge. This was noted in increased percentage of respondents reporting “quite a bit” or greater comprehension, especially in areas of disease risk factors(55%pre vs 63%post), disease side effects(55%pre vs 63%post), and health care navigation(53%pre vs 69%post). The reported desire for “quite a bit” or more increased understanding on various topics did decrease post symposium regarding their disease(87.9% pre vs 68.9%post), disease risk factors(86.3%pre vs 64.0%post), screening tests(74.7%pre vs 63.3%post), and nutrition(78.4%pre vs 64.9%post)(all p<0.05). There was no significant decrease in the desire for increased understanding managing stress and fatigue. Summary: Demonstrated in this study, individuals choosing to attend a patient-centered cancer symposium, seek to improve an already solid knowledge base. Study participants indicate a significant desire for increased information on all topics, even those with sufficient level of knowledge reported. This indicates that some cancer patients’ thirst for knowledge is difficult to quench, and may benefit from recurrent education opportunities. The improvement in almost all topics assessed indicates a patient centered symposium is an effective method to provide information to patients regarding the spectrum of cancer health management. Disclosures No relevant conflicts of interest to declare.

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 Background: Donor cell chimerisms are tested at frequent intervals after allogeneic hematopoietic stem cell transplantation (alloHSCT). However, the predictive value of this testing in patients with myelofibrosis (MF) is not well-defined. In this study, our primary objective is to evaluate the correlation of day 30 and day 100 donor cell chimerism and overall survival (OS) in patients (pts) who undergo alloHSCT for MF. Methods: Charts were reviewed for pts who underwent alloHSCT for MF at Mayo Clinic in Arizona, Minnesota and Florida between January 2005 and December 2015. Patients who died within 30 days of alloHSCT were excluded. Chimerism studies were evaluated in the peripheral blood for CD3 and CD33 fractions at day +30 (D30) and day +100 (D100). Cut-off value of 100% and less than 100% was used because of limited variability below 100%. Standard statistical methods were used to compare continuous and categorical variables. The Kaplan-Meier method was used to provide survival curves. Results: Baseline characteristics: Sixty three consecutive patients who underwent alloHSCT for MF since January 2005 until December 2015, and had D30 and/or D100 chimerism studies available were included in the study. Of these, 24 (38%) were female. Median age at diagnosis was 56 years (range, 19 - 73 years) and median age at AHSCT was 58 years (range, 19 - 73 years). Dynamic International Prognostic Scoring System-Plus (DIPSS-Plus) risk category at the time of alloHSCT was high in 31 (49%), intermediate-2 in 30 (48%) and intermediate-1 in 2 (3%) pts. JAK2 V617F mutation status was available in 61 pts and was positive in 35 (57%) pts. Nineteen (30%) pts had been treated with a JAK2 inhibitor prior to alloHSCT. Fifty-two (83%) pts had at least grade-2 fibrosis in bone marrow at the time of HCT. Transplantation: Median time from diagnosis to AHSCT was 12.9 months (range, 2.3 - 248.2 months). Fifty-five (87%) received a reduced intensity conditioning (RIC) regimen while 8 (13%) received myeloablative conditioning regimen. Of these 55 pts, RIC regimens used were busulfan fludarabine based regimen in 15 (27%), fludarabine melphalan based regimen in 18 (33%) and fludarabine melphalan carmustine in 22 (40%) pts. Donor source was matched related in 30 (48 %), matched unrelated in 28 (44%), single-antigen mismatched related in 4 (6%) and mismatched unrelated in 1 (2%). Peripheral blood stem cells were used in all AHSCTs. Outcomes: Median follow-up was 24.4 months (range, 1.5 - 83.6 months). Amongst pts who had <100% donor chimerism at D30 in CD33 fraction, 2 had 90%, 1 had 80% and 2 had zero% donor chimerism. At D100, 1 pt had 95%, 1 had 90%, 1 had 60%, 2 had 5% and 1 had zero% donor chimerism. Eighteen out of 57 (32%) pts who had 100% donor chimerism in CD33 fraction at D30 had died at the time of analysis compared to 4 out of 5 (80%) patients with less than 100% (p=0.03). Eight out of 38 pts (21%) who had 100% donor chimerism in CD33 fraction at D100 died versus 3 out of 6 (50%) with less than 100% (p=0.12). There was no significant survival effect of CD3 chimerism (p values=0.68, 0.59). Of the 23 deaths that had occurred at the time of analysis, cause of death was disease progression or relapse in 8 (35%), graft versus host disease in 6 (26%), transplant related (sepsis / engraftment failure) in 5 (22%) and unrelated causes in 4 (17%). Survival analysis: As depicted in the Kaplan Meier curve (figure 1), median overall survival (OS) for pts with 100% donor chimerism in CD33 fraction at day 30 was not reached while for <100% donor chimerism was 16 months (p=0.04). Survival at 3 years for patients with 100% CD33 donor chimerism at D30 was 65% while it was 40% for pts with less than 100%. Also, survival at 3 years for patients with 100% CD33 donor chimerism at day 100 was 75% compared to 50% for patients with less than 100%. Conclusions: In our study, 100% donor chimerism in CD33 fraction is associated with improved survival after alloHSCT for MF compared to pts with less than 100%. Further understanding regarding the reason for this relationship is critical. Larger studies to replicate these results would be imperative to validate these findings. Disclosures Mesa: Incyte: Research Funding; Ariad: Consultancy; Promedior: Research Funding; Novartis: Consultancy; Celgene: Research Funding; Gilead: Research Funding; CTI Biopharma: Research Funding; Galena: Consultancy.

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 Abstract 1744 Background: MF, ET and PV are BCR ABL negative myeloproliferative neoplasms (MPN). These are a subset of bone marrow disorders characterized by an overproduction of one or more types of blood or fiber cells in the bone marrow. There is disparate published data on the epidemiological estimates for these diseases in the EU. An evidence based synthesis of MPN epidemiology data can effectively inform population health care planning and economic decision support for these disorders. The aim of our study is to synthesize and provide a comprehensive review of epidemiology estimates from available sources including literature, publicly available registries as well as real world data. Methods: We conducted a search of literature published between 1995–2012 using terms related to MF, PV and ET. Elsevier and Medline databases were searched using Embase platform. Orphan disease registries, specific hematological malignancies registries, country specific databases and registries included RARECARE, Orphanet, Registry of hematological malignancies in France, UK Hematologic Malignancy research network. Finnish cancer registry and Sweden National registry were also evaluated. The RARECARE project is responsible for surveillance of rare cancers in Europe based on data from 88 cancer registries in 22 European countries and includes cancer cases diagnosed in 1995–2002. Orphanet provides an estimate of the prevalence of rare diseases in Europe based on a systematic survey of the literature. Calculation of prevalence in Orphanet is done by multiplying incidence with the mean duration of disease. UK THIN (∼5 million enrollees each year) general practitioner database was used to retrospectively identify patients with primary and secondary MF between 1/1/08 and 12/31/10. READ codes were used to identify MF. This database can track patients longitudinally over multiple years, are linked at the patient level by a unique identifier that is consistent across health related services and time and have been shown to be representative of the UK population. Results: Only six articles looking at the European population were retrieved through the literature. These articles as well as international/national reports were used to summarize epidemiological estimates for Myelofibrosis using several different terms. MF terminology varied among registries. Terms included “Primary myelofibrosis”, “myelosclerosis with myeloid metaplasia” and “myelofibrosis”. Annual prevalence of MF ranged from 0.5–9 cases per 100,000 individuals. For PV, even if terminology and coding is consistent, estimates still varied depending on registry used. RARECARE reported prevalence of 5.5 per 100,000 and Orphanet reported a range of 10–50 cases per 100,000. For ET, prevalence was reported only in RARECARE with 4.4 cases per 100,000 individuals. Prevalence estimates in UK were slightly higher compared to RARECARE; 0.9 cases per 100,000 for MF, 6 cases per 100,000 for PV and ET. Incidence for MF, PV and ET ranged from 0.3–1.9, 0.6–2.8, 0.5–2.2 per 100,000 patients respectively. Conclusions: Few publications and registries report epidemiology data for MF, PV or ET. Especially, prevalence data is very rare. There is wide variation in both prevalence and incidence estimates for MPN across EU data sources that can limit informed application of epidemiological research. The differences stem from lack of a unifying term for MF and coding differences coupled with limitations inherent in registry data including potential sources of bias, missing data, and issues with assessment of statistical significance. Additional research using standardized definitions/coding across appropriate real world databases and enhanced tumor registries are needed to add precision to or substantiate these results. Disclosures: Moulard: Sanofi: Employment, Equity Ownership. Mehta:Sanofi: Employment. Olivares:Sanofi: Employment, Equity Ownership. Iqbal:Sanofi: Employment, Equity Ownership. Mesa:Incyte: Research Funding; Lilly: Research Funding; Sanofi: Research Funding; NS Pharma: Research Funding; YM Bioscience: Research Funding.

Abstract Abstract 1727 Background: Myelofibrosis (MF) is characterized by cytopenias, splenomegaly, and burdensome symptoms that may worsen over time. Ruxolitinib (RUX) has been shown to reduce splenomegaly and improve MF-associated symptoms in 2 phase III studies, including COMFORT-I, a randomized, double-blind, placebo (PBO)-controlled trial, which also showed prolonged survival in favor of RUX. Purpose: In this post hoc analysis of COMFORT-I, the efficacy of RUX in patients with varying degrees of splenomegaly and symptom severity at baseline was evaluated to assess the potential effects of earlier versus later intervention in this progressive disease. Methods: COMFORT-I participants randomized to RUX (n=155) or PBO (n=154) had MF with an International Prognostic Scoring System (IPSS) score ≥2 and a platelet count of ≥100 × 109/L. Patients with protocol-defined worsening splenomegaly were permitted to cross over from PBO to RUX. The primary endpoint was the percentage of patients with ≥35% reduction in spleen volume (SV) at week (wk) 24. Change in Total Symptom Score (TSS) was a secondary endpoint. TSS was the sum of 6 symptom scores (night sweats, itching, abdominal discomfort, pain under ribs on left side, early satiety, muscle/bone pain) assessed with the modified MF Symptom Assessment Form (MFSAF) v2.0 on a scale of 0 (“absent”) to 10 (“worst imaginable”). Patients were stratified by palpable spleen length (SL) (≤ 10 cm, <10 to 20 cm, >20 cm) and TSS tertile (≤11.1, >11.1 to 22.0, >22.0) at baseline. SV and TSS stratified by baseline values as described were summarized over time. To account for PBO crossover, modeling was performed to predict SV after crossover using a nonlinear mixed model that best predicted individual patient data. Last observation carried forward was used to impute missing TSS data. Results: Mean absolute SV and TSS worsened over time in the PBO group regardless of baseline SL and TSS, demonstrating the progressive nature of MF. In patients treated with RUX, mean absolute SV and TSS at wk 24 were lower for patients with smaller SL and less severe TSS at baseline, respectively (Table); absolute differences with PBO were significant within each subgroup. Therefore, patients who initiated RUX therapy with more advanced MF were less likely to achieve the same clinical status experienced by patients initiating therapy with less advanced MF. Notably, even after 24 wks of RUX treatment, SV and TSS reductions in the cohorts with larger SL or greater TSS at baseline did not achieve levels equivalent to baseline of the next lesser baseline severity group (Table; Figure). Although the severity of splenomegaly and symptoms at baseline influenced the absolute SV and TSS achieved at wk 24, RUX treatment resulted in similar percent reductions in SV and improvements TSS across all subgroups, with the exception of the lower TSS tertile (where there is less room for improvement). In contrast, PBO treatment resulted in increases in SV and worsening of symptoms and patients with less severe SV and TSS at baseline experienced the greatest percent increases in SV and TSS at wk 24. Conclusions: RUX therapy was associated with SV reduction and symptom improvement regardless of spleen size or symptom severity at baseline, whereas patients on PBO experienced disease progression across all subgroups. Patients receiving RUX with less advanced disease achieved an overall better clinical status, as defined by lower absolute SV and symptom scores. This analysis suggests that initiation of RUX in patients with less severe splenomegaly and symptoms may contribute to improved patient outcomes. Disclosures: Mesa: Incyte: Research Funding; Lilly: Research Funding; Sanofi: Research Funding; NS Pharma: Research Funding; YM Bioscience: Research Funding. Gotlib:Incyte: Consultancy. Kantarjian:Incyte: grant support Other. Sun:Incyte: Employment. Verstovsek:Incyte Corporation: Research Funding.

Abstract Abstract 1736 Background: Histone deacetylase inhibition (HDACi) has shown a potent inhibitory activity on the autonomous proliferation of hematopoietic cells of PV and ET patients carrying the JAK2V617F mutation (Leukemia. 2008;22(4):740–7). Hematological responses have been recorded during treatment with the HDACi givinostat in patients with PV and myelofibrosis (Blood. 2011; 118:a1748). Additionally, combinational use of givinostat and hydroxyurea (HU) have shown encouraging clinical response in PV (Br J Haematol. 2010;150:446–55). Recent laboratory studies of vorinstat-treated JAK2V617F knock-in mice have observed normalization of peripheral blood counts, markedly reduced splenomegaly and decreased mutant allele burden (Blood 2012; 119, 3779–89). Despite this evidence of hematologic response, to date no studies have evaluated specific changes in symptom burden among PV and ET patients treated with HDACi. METHODS ET and PV patients from the UK were enrolled in a non-randomized, open-label phase II multicenter study of the HDACi vorinostat (Haematologica 2011;96(s2):a1023). Patients were asked to complete the 18 item Myeloproliferative Neoplasm Assessment Form (MPN-SAF) (Blood 2011;118:401–408), 9 item Brief Fatigue Inventory (BFI) (Cancer 1999;85:1186–1196) and 30 item EORTC QLQ-C30 (J Natl Cancer Inst 1993; 85(5):365-76) at enrollment, week 12, week 24, and week 36. From weeks 1 through 24, participants were given 400mg of vorinostat daily and were observed from weeks 24 to 36. RESULTS Participant Demographics and Mutational Status: 15 PV and 10 ET patients were enrolled in the study. Median age of participants was 65 and 48% of participants were female. JAK2 mutations were present in 5/10 (50%) of ET and 14/15 (93%) of PV patients. Change in Symptom Severity with Vorinostat: Although most symptom severity changes did not reach statistical significance likely due to the small sample size, individual symptoms of headache (mean 1.6 baseline to 0.5 wk 36, mean maximum improvement 0.5 from baseline), dizziness (mean 1.6 baseline to 0.9 wk 36, mean maximum improvement 0.6 from baseline), sad mood (mean 2.6 baseline to 1.9 wk 36, mean max improvement 0.2 from baseline), and bone pain (mean 2.7 baseline to 0.8 wk 36, mean max improvement 0.7 from baseline) indicated consistent reductions in severity. Change in Symptom Incidence with Vorinostat: Non-sustained reductions in symptom incidence were seen with initiation of therapy for items of dizziness (50% baseline, 43% wk12, 55% wk 24, and 38% wk 36), numbness (65% baseline, 38% wk 12, 36% wk 24, 63% wk 36), sad mood (55% baseline, 47% wk 12, 40% wk 24, 50% wk 36), and itching (65% baseline, 50% wk 12, 40% wk 24, 75% wk 36). Change in MPN-SAF TSS Score with Vorinostat: Overall, MPN-SAF TSS did not vary significantly for the cohort over the course of the study (score change −.4 week 12, −0.5 week 24, −1.2 week 36, Figure 1). However, 9/17 participants who had a TSS of at least 6 at baseline had an overall improvement of at least 6 points (a moderate improvement) on at least one assessment after baseline. Of these, 5 of those 9 participants had an improvement of at least 10 points, which constitutes a large improvement in symptom burden based on a distributional definition of clinical significance using the standard deviation from a previous cohort. CONCLUSION This study represents the first analysis of symptom burden among PV and ET patients receiving vorinostat to date. In addition to previously identified changes in clinical and hematologic response, reductions in symptom burden including QOL and fatigue were observed in patients receiving vorinostat therapy which was most noticeable in patients with high baseline burden. The toxicity profile of vorinostat also suggests that better results might have observed if individualized assessment of clinicohematological responses including an integrated a marker for response into daily clinical practice and tailoring pharmacotherapy based on side effect profile (Leukemia. 2012;26(5):1148–9). Although further investigation among larger cohorts is needed, preliminary data is encouraging for successful therapeutic use of vorinostat in a clinical setting and with possible combinational therapy to reduce symptom burden among PV and ET patients. Disclosures: Harrison: Novartis: Honoraria, Research Funding, Speakers Bureau; YM Bioscience: Consultancy, Honoraria; Sanofi Aventis: Honoraria; Shire: Honoraria, Research Funding. Mesa:Incyte: Research Funding; Lilly: Research Funding; Sanofi: Research Funding; NS Pharma: Research Funding; YM Bioscience: Research Funding.

Abstract Abstract 1737 Background: The somatic JAK2 V617F (V617F) mutation is found in approximately 95% of polycythemia vera (PV) and 50–60% of essential thrombocythemia (ET) and primary myelofibrosis (PMF) patients. Detection of this mutation occurs primarily through genomic analysis of peripheral blood samples of myeloproliferative neoplasm (MPN) patients. This study demonstrates a novel broad screening mechanism for detection of V617F from myeloid cells in saliva samples from an online cohort of MPN patients and from a broader database of genotyped individuals. Methods: MPN patients were recruited primarily through social media and patient-mediated outreach efforts. Patients gave IRB-approved consent and completed surveys through an online 23andMe account. Participation in the MPN research initiative was free. In collaboration with an uncompensated panel of academic experts, online surveys were developed to collect patient-reported data on diagnosis and results of genetic testing for the V617F mutation. Participants were genotyped on SNP arrays based on the Illumina Omni Express, with additional custom content, including four probes for the V617F mutation. We estimated V617F mutation burden as the median across the four probes of B/(A+B) where A and B were normalized intensities for the reference and mutated alleles, respectively. We estimated sensitivity and specificity of our estimated V617F allele ratio, using the self-reported V617F-positive individuals to approximate the distribution of true positives, and 23andMe members from the broad database (outside of the MPN research cohort) and younger than 40 as likely true negatives. Results: Web-based recruitment efforts led to the accrual of over 900 MPN patients of different subtypes over 12 months. Of these participants, 745 patients have been genotyped and provided MPN-related health history and outcomes through online surveys. The cohort is disproportionately female (71%), with an average age of 53.1 ± 14.9 years. More than 57% of patients indicated a classic MPN diagnosis (PV, ET, PMF, or post PV/ET MF), 19.2% reported an atypical MPN diagnosis (systemic mastocytosis or hypereosinophilic syndrome), 14.5% indicated chronic myelogenous leukemia, and 9.3% of the cohort reported other diagnoses. From this MPN cohort, a total of 345 participants reported mutation test results. Consistent with expectations, the V617F variant was reported by patients in nearly all PV cases (105 of 110 patients with a self-reported diagnosis of PV), and at a lower rate in ET and MF cases (59 of 95 patients and 48 of 61 patients, respectively). In addition to self-reported data, we were specifically able to detect the V617F mutation using SNP array data. We determined a detection threshold for the V617F variant at which 86% of self-reported V617F carriers were scored as positive (i.e. test sensitivity), and 99.975% of young 23andMe customers were scored as negative (i.e. test specificity). Participants with a classic diagnosis in the MPN cohort who carry the V617F variant tended to be older (mean age=59.5 versus 54.6 years) and were less likely to be female (62.5% versus 72.0%) than non-carriers. At this threshold, we detected 133 individuals who likely carry the V617F mutation among a broader set of 23andMe participants (n= 99,700) who were not specifically recruited for the MPN study, corresponding to a prevalence of 0.14%. We estimated the positive predictive value of the test in this cohort, or the expected proportion of positive test results that are true, as 81%. Within the general 23andMe cohort, the frequency of the V617F variant increases with participant age, from a rate of 0.017% for age 20 to 30, to 1.1% for age 80 to 90. We also observed that patients with a high allele burden of V617F frequently had acquired uniparental disomy of chromosome 9p, as determined from calculated heterozygosity scores and no-call rates for this chromosomal arm. Conclusion: We can detect V617F with high specificity and sensitivity from myeloid cells in saliva. This non-invasive source for DNA extraction offers new possibilities for detecting genomic alterations and for finding novel genetic associations in MPN patients as well as the general population. This study demonstrates the feasibility of online technology to significantly accelerate recruitment and research progress in MPNs and other rare diseases. Disclosures: Barnholt: 23andMe, Inc.: Employment. Hinds:23andMe: Employment, Equity Ownership, Patents & Royalties. Kiefer:23andMe, Inc.: Employment. Do:23andMe, Inc.: Employment, Equity Ownership, Patents & Royalties. Eriksson:23andMe, Inc.: Employment, Equity Ownership, Patents & Royalties. Mountain:23andMe, Inc.: Consultancy, Employment, Honoraria, Patents & Royalties. Francke:23andMe, Inc.: Employment, Honoraria, Research Funding; Locus Development: Consultancy, Membership on an entity's Board of Directors or advisory committees. Tung:23andMe, Inc.: Employment. Mesa:23andMe, Inc.: Unpaid advisor and collaborator Other. Gotlib:23andMe, Inc.: Unpaid advisor and collaborator Other. Zehnder:23andMe, Inc.: Unpaid advisor and collaborator Other.

Abstract Background:Patients with polycythemia vera (PV) often present with a broad range of clinical characteristics that may contribute to increased risks of cardiovascular (CV) morbidity and mortality, including thrombotic events (TE). Limited contemporary real-world data have been reported about the clinical burden of PV and treatment patterns in the United States. The ongoing REVEAL study collects data on disease burden, clinical management, patient-reported outcomes, and healthcare resource utilization for patients with PV in the United States. This analysis reports clinical characteristics, including underlying CV risk factors, for patients enrolled in the REVEAL study as of April 28, 2016. Methods: REVEAL is a multicenter, nonrandomized, prospective, observational study enrolling patients ≥18 years of age with a PV diagnosis who are actively managed in an academic or community setting. For this analysis, data regarding PV disease and diagnosis, clinical characteristics, and treatment patterns were collected at enrollment during usual-care visits and were based on physician assessment, electronic medical records, and local laboratory values. Ten-year CV risk factors selected for this analysis were adapted from the Framingham Heart Study for CV diseases. Results: At data cutoff, 2307 patients were available for this analysis. Mean (SD) age was 66.3 (12.2) years, 54.4% were male, 89.9% were white, 62.7% had at least some college education, and 51.1% were retired. Approximately 6% of patients had a family history of PV, primarily in parents (35.1%) and siblings (33.8%). A history of second malignancies was reported for 344 patients (14.9%). The majority of patients (84.6%) were diagnosed with PV based on an abnormal blood test alone or in combination with a bone marrow test. Among patients who were diagnosed with a mutational test (n=1078), 95.2% were diagnosed via an abnormal JAK2V617F test result. Abnormal hemoglobin (57.3%), hematocrit (55.4%), or both (47.5%) were among the most common blood values assessed for PV diagnosis. At diagnosis, 58.5% of patients were classified with high-risk PV (age ≥60 years or history of a TE); this percentage increased to 77.3% at REVEAL enrollment. The average (SD) disease duration from diagnosis to enrollment was 5.8 (6.1) years. At enrollment, 91.5% of patients were under active management for PV (phlebotomy ± aspirin, 34.0%; hydroxyurea ± aspirin, 27.0%; and phlebotomy + hydroxyurea ± aspirin, 23.2%). Underlying CV risk factors that were either diagnosed or treated in 86.0% of enrolled patients included hypertension (66.5%), history of smoking (46.2%), current smoking at enrollment (10.9%), obesity (34.2%), hyperlipidemia (27.4%), and diabetes (14.8%). At enrollment, 431 (18.7%) patients reported having ≥1 TE, including 181 patients who had a TE between PV diagnosis and enrollment. Venous and arterial TEs were reported in 11.1% and 8.6% of patients, respectively. Most commonly reported venous TEs were deep vein thrombosis (5.9%) and pulmonary embolism (2.5%); most common arterial TEs were cerebrovascular arterial thrombosis including transient ischemic attack (5.1%) and acute myocardial infarction (1.7%). Increased rates of TEs were observed among patients with hyperlipidemia (23.6%) and hypertension (21.0%; Table 1), compared with patients who did not have any risk factors (10.5%). Conclusion: A large proportion of patients in the REVEAL study had 1 or more underlying CV risks, including age, hypertension, smoking, obesity, hyperlipidemia, and diabetes, which may contribute to the risk of thrombosis. Longitudinal data from REVEAL will provide a better understanding of how these factors affect CV outcomes over time. Disclosures Stein: Incyte Corporation: Membership on an entity's Board of Directors or advisory committees, Research Funding. Naim:Incyte Corporation: Employment, Equity Ownership. Grunwald:Janssen: Research Funding; Forma Therapeutics: Research Funding; Medtronic: Equity Ownership; Alexion: Membership on an entity's Board of Directors or advisory committees; Ariad: Membership on an entity's Board of Directors or advisory committees; Amgen: Research Funding; Incyte Corporation: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Oh:Incyte Corporation: Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Research Funding; CTI: Research Funding. Paranagama:Incyte Corporation: Employment, Equity Ownership. Cordaro:Incyte Corporation: Employment, Equity Ownership. Sun:Incyte Corporation: Employment, Equity Ownership. Parasuraman:Incyte Corporation: Employment, Equity Ownership. Boccia:Celgene: Consultancy, Honoraria, Speakers Bureau; Amgen/Onyx: Consultancy, Honoraria, Speakers Bureau; Gilead: Speakers Bureau; Genentech: Consultancy, Honoraria, Speakers Bureau; Eisai: Consultancy, Honoraria, Speakers Bureau. Mesa:Ariad: Consultancy; CTI: Research Funding; Gilead: Research Funding; Galena: Consultancy; Novartis: Consultancy; Promedior: Research Funding; Celgene: Research Funding; Incyte Corporation: Research Funding.