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Introduction: The NHLBI MDS Natural History Study (NCT02775383) is an ongoing prospective cohort study conducted across 144 sites in the U.S. and Israel intended to establish a data and biospecimen repository to advance the understanding of MDS. In response to the COVID-19 pandemic, the study also collected data on COVID-19 infection and management. Here, we report a summary of COVID-19 outcomes from participants in this study and the impact of the pandemic on study operations. Methods: This prospective cohort study initiated in June, 2016 is enrolling patients (pts) undergoing diagnostic work up for suspected or newly diagnosed MDS or MDS/myeloproliferative neoplasms (MPNs) in the setting of cytopenia. Study enrollment was paused from Mar. 27, 2020 to May 18, 2020 due to COVID-19. Previously untreated pts underwent a bone marrow assessment with a centralized histopathology review at enrollment for assignment to a longitudinal cohort (MDS, MDS/MPN overlap, idiopathic cytopenia of undetermined significance (ICUS), acute myeloid leukemia (AML) with Results : Of 758 eligible pts with available COVID-19 data, 507 (67%) were assigned to the longitudinal cohort and 251 (33%) to the cross-sectional cohort or are pending assignment. Among longitudinal pts, 74 (15%) had ICUS, 240 (47%) MDS, 47 (9%) MDS/MPN overlap, 11 (2%) AML with Among 244 pts (32%) tested for COVID-19 (Table 1), 23 (9%) were positive. Twelve (>50% of the positive pts) were in Wisconsin, California (CA), and Missouri (Figure 1), with 8 identified from Sep. to Dec. 2020, which overlaps with third waves of COVID-19 reported in CA and in the Midwest. Tests from 17 (74%) of the 23 pts were based on a polymerase chain reaction (PCR) assay. The proportion of pts positive were similar between pooled disease (ICUS, MDS, MDS/MPN, AML Among all positive pts, 21 (91%) are recovering or have recovered (16 with sequelae), 1 (4%) died, and 1 outcome is unknown (Table 1). The one participant who died had MDS with excess blasts-1 (MDS-EB1, 5-9% blasts). Eight pts (35% of positive pts) required hospitalization (median duration of 7 days (range=2-17)) or treatment (tx) in response to COVID-19, 7 of whom required both. In the 8 pts who required tx for COVID-19, 4 reported Remdesivir-use, 3 of whom were diagnosed with MDS or MDS/MPN overlap. The study monthly accrual rates were similar when compared pre- vs. post-study pause (23 vs. 22 pts, respectively) but the rate of missed follow-up visits increased from 5% to 11% post-pause. About half (49%) of the 144 COVID-19-related study deviations occurred during the months the study was paused. Conclusions: In this analysis of 758 pts with MDS and related conditions, the largest reported for these diagnoses, the COVID-19 mortality rate (13%) in MDS was lower than has been reported in a smaller (n=61) case study (39%, Feld et al Blood 2020) but is similar to the rates for MDS observed annually each year prior to study pause (range=11-19%) and to the rate reported in a larger (n=2186) observational study of cancer patients (16%, Rivera et al Cancer Discov 2020). Infection rates were similar across disease groups. The pandemic also resulted in substantial study-specific challenges, including increased rate of deviations, the study being paused, and difficulty sourcing material for biospecimen processing. Data on vaccine efficacy and rates of pts with long-haul symptoms post-COVID may be of interest in future work. Figure 1 Figure 1. Disclosures Padron: BMS: Research Funding; Kura: Research Funding; Taiho: Honoraria; Stemline: Honoraria; Blueprint: Honoraria; Incyte: Research Funding. Komrokji: Novartis: Honoraria; Geron: Honoraria; Acceleron: Honoraria; Agios: Honoraria, Speakers Bureau; Abbvie: Honoraria, Speakers Bureau; JAZZ: Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau. Saber: Govt. COI: Other. Al Baghdadi: Bristol-Myers Squibb: Current holder of individual stocks in a privately-held company, Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Current holder of individual stocks in a privately-held company; Epizyme: Current holder of individual stocks in a privately-held company; Heron Therapeutics: Current holder of individual stocks in a privately-held company; Morphosys: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Cardinal Health: Membership on an entity's Board of Directors or advisory committees. DeZern: Taiho: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees. Sekeres: Novartis: Membership on an entity's Board of Directors or advisory committees; Takeda/Millenium: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees.

Introduction: The NHLBI National MDS Study (NCT02775383) is a prospective cohort study conducted at 92 community hospitals and 29 academic centers. It enrolls patients undergoing work up for suspected MDS to understand the genetic, epigenetic, and biological factors associated with the initiation and progression of the disease. Previously untreated, cytopenic participants undergo both local and centralized pathology review and are assigned a diagnosis, including MDS, MDS/MPN, AML with blasts < 30%, and "Other". Emerging data suggests that Next Generation Sequencing (NGS), along with cytogenetics and clinical variables, may improve MDS diagnostic precision. Given that our study relies on central review (with additional tertiary pathology review used to adjudicate disagreements), we examined whether targeted gene sequencing data could be used to increase the agreement between local and central pathologic diagnosis of MDS vs. Other. Methods: Peripheral blood and bone marrow (BM) biopsy specimens from cytopenic patients, along with clinical history, CBC, and other results including karyotyping, FISH and pathology reports from local pathologists were reviewed by central pathologists. The updated 2016 WHO classifications were used to diagnose MDS. Targeted exon sequencing of 96 genes was performed using BM specimens. A subset of 648 individuals that were classified as MDS (n=212) or Other (n=436, including 90 CCUS and 89 individuals with other cancers) by pathology assessments were selected. A mean coverage of 1,317X was achieved and variants had a minimum variant allele frequency (VAF) of 2% (except FLT3). Variants for 596 subjects were manually reviewed to retain likely disease-causing variants to build a binary classifier (MDS vs. Other) using the maximum VAF per gene as input (Figure 1). Subjects diagnosed with MDS or Other by both central and local pathology were used for training, validation, and testing, and were considered "gold standard" (GS) cases (n=546). These subjects were split into 4 random groups with equal proportions of MDS cases. 75% of the GS cases were used to train and validate lasso-regularized logistic regression models using 3-fold cross validation. ROC curve analysis was carried out using the remaining 25% of GS cases (Test Set 1) on the best model to identify an optimal probability cut off point for classifying subjects as MDS. Model performance was then tested on 50 subjects for which the central and local pathology diagnosis disagreed (Test Set 2), as well as on 52 additional subjects irrespective of agreement (Test Set 3). Results : The best performing logistic regression model retained 7 genes as most informative in a discriminating diagnosis of MDS from Other based on their VAFs, in order of impact: TP53, SF3B1, U2AF1, ASXL1, TET2,STAG2, and SRSF2. We used this model to assign probabilities for each of the subjects in Test Set 1 and to estimate the performance using ROC analysis (Figure 1), resulting in a high area under the curve (AUC) of 0.89. We chose a probability cut-off of ≥0.17, being associated with a high percentage of correct classification of MDS with a sensitivity and specificity of 0.90 and 0.81, respectively. Among the cohort of 50 subjects with a discordant local and central pathology diagnosis (Test Set 2), the classifier accurately reassigned 37 subjects (accuracy = 74%) from the local to the central pathology. The blinded tertiary pathology reviewer agreed with central in all Test Set 2 cases. This included 24/34 MDS cases that had been labeled as Other by local pathology (positive predictive value [PPV]=0.89). 3/16 final pathology-classified Other cases were mis-classified as MDS by the local pathologist (negative predictive value [NPV] = 0.57). Next, we assessed the ability of the model to predict MDS vs. Other for 52 additional independent subjects using the third pathologist's diagnosis to break any ties (Test Set 3). The classifier correctly predicted 15/21 MDS cases (PPV=0.83) and misclassified 6/31 Others as MDS (NPV=0.82). The overall accuracy was 83%. Conclusions: We identified that VAFs for 7 genes can correctly re-classify subjects as either MDS or Other in 74% of cases that were misclassified between local and central pathology review. Further assessment on an independent cohort showed an accuracy of 83% of the model. Taken together, these data suggest that complementing pathology reviews with targeted sequencing of 7 genes could improve MDS diagnosis. Disclosures Lindsley: MedImmune: Research Funding; Jazz Pharmaceuticals: Consultancy, Research Funding; Bluebird Bio: Consultancy; Takeda Pharmaceuticals: Consultancy. Bejar:Aptose Biosciences: Current Employment; AbbVie/Genentech: Honoraria; Astex/Otsuka: Honoraria; Takeda: Honoraria, Research Funding; Celgene/BMS: Honoraria, Research Funding; Daiichi-Sankyo: Honoraria; Forty-Seven/Gilead: Honoraria; Genoptix/NeoGenomics: Honoraria. DeZern:MEI: Consultancy; Astex: Research Funding; Abbvie: Consultancy; Celgene: Consultancy, Honoraria. Foran:H3Biosciences: Research Funding; Aptose: Research Funding; Kura Oncology: Research Funding; Trillium: Research Funding; Takeda: Research Funding; Revolution Medicine: Consultancy; Xencor: Research Funding; Agios: Honoraria, Research Funding; Aprea: Research Funding; Actinium: Research Funding; Servier: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Abbvie: Research Funding; BMS: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; Boehringer Ingelheim: Research Funding. Gore:Abbvie: Consultancy, Honoraria, Research Funding. Komrokji:Acceleron: Honoraria; Incyte: Honoraria; Abbvie: Honoraria; Agios: Speakers Bureau; BMS: Honoraria, Speakers Bureau; Jazz: Honoraria, Speakers Bureau; Geron: Honoraria; Novartis: Honoraria. Maciejewski:Alexion, BMS: Speakers Bureau; Novartis, Roche: Consultancy, Honoraria. Padron:Novartis: Honoraria; BMS: Research Funding; Incyte: Research Funding; Kura: Research Funding. Starczynowski:Captor Therapeutics: Consultancy; Tolero Therapeutics: Research Funding; Kurome Therapeutics: Consultancy, Current equity holder in private company, Research Funding. Sekeres:BMS: Consultancy; Takeda/Millenium: Consultancy; Pfizer: Consultancy.

Introduction: Myelodysplastic syndromes (MDS) are a heterogenous group of blood disorders defined by peripheral cytopenia(s), bone marrow failure, morphological dysplasia, and risk of progression. To understand the genetic, epigenetic and biological factors associated with the initiation and progression of MDS, NHLBI created the National MDS Study (NCT02775383). This is a prospective cohort study conducted at 92 community hospitals and 29 academic centers enrolling patients undergoing diagnostic work up for suspected MDS or MDS/myeloproliferative neoplasm (MPN) overlap syndrome. Eligible patients have yet to receive any therapy directed at their cytopenias. Previously untreated cytopenic participants underwent centralized histopathology and data review at the time of enrollment for assignment into distinct subcategories: MDS, MDS/MPN overlap, AML, and Other. Targeted exon sequencing of 96 genes was performed using marrow specimens from the first 300 consecutive individuals in the study. Here we report the genetic mutations for this cohort. Methods: NovaSeq 6000 was used for deep sequencing at a mean coverage of 1,286X and mean breadth (bases covered at ≥100X) of 99.8%. Reads were aligned against build GRCh38 using BWA-MEM, and VarScan2 was used to detect SNVs and INDELS. Variants were filtered for those with an allele base quality of >25 in combination with rule-based and manual review criteria. Subjects in the Other category without an identified malignancy were considered clonal cytopenias of undetermined significance (CCUS) when a mutation or a clonal cytogenetic change was present. Fisher's exact and Wilcoxon rank sum tests in combination with Bonferroni correction were applied to compare groups. Results : A total of 350 putative nonsynonymous pathogenic variants in 36 genes with an allele frequency of >.05 were identified across 150 patients (50%). At least one variant was noted in the following proportion of individuals: 61/72 (85%) with MDS, 13/13 (100%) with MDS/MPN, 15/17 (88%) with AML, and 61/198 (31%) in the Other category, of which 48 were CCUS and 13 were other cancers. Two CCUS patients only had a cytogenetic abnormality. Table 1 shows the distribution of variants in each subcategory of patients for the most commonly mutated genes in our cohort of 300 subjects. Mutations in these genes were enriched in specific groups: SF3B1, STAG2,TP53, and ASXL1 in MDS; TET2 in MDS/MPN; and IDH2 and TP53 in AML (one-sided p Pair-wise comparisons of baseline characteristics of subjects between MDS, MDS/MPN, AML, or CCUS groups revealed no significant differences for age or sex. The CCUS group had significantly higher hemoglobins than the MDS group with median hemoglobin levels of 11.35 and 9.40 g/dL, respectively (p 110x109/L , respectively, p There was no difference in the median number of variants per patient between groups or correlation with age (rs=0.11, p=0.18). The maximum variant allele frequency (maxVAF) per patient was highest in the MDS/MPN group (median = 0.42, range = 0.38-0.91) and lowest in the CCUS group (median = 0.37, range =0.06-0.98) with the MDS/MPN group having a significantly higher maxVAF compared to the MDS and the CCUS groups (p Conclusions: Incorporation of gene-panel sequencing in the comprehensive evaluation of 300 adult cytopenic patients identified half of the cohort with potentially pathogenic variants. Ultimately, a diagnosis of CCUS was possible in 48 of 183 subjects (26%) not diagnosed with MDS, MDS/MPN overlap syndrome, AML, other cancers or clonal cytogenetics. This study continues to serially bank samples from patients with CCUS, in addition to MDS, MDS/MPN, and ICUS, with the goal to better understand the natural history of these diseases and their progression. Disclosures Lindsley: Jazz Pharmaceuticals: Research Funding; Takeda Pharmaceuticals: Consultancy; Medlmmune: Research Funding. Bejar:Celgene: Consultancy; Takeda Pharmaceuticals: Research Funding; AbbVie/Genentech: Consultancy, Honoraria; Astex/Otsuka: Consultancy; Modus Outcomes: Consultancy; Daiichi-Sankyo: Consultancy. Al Baghdadi:Celgene: Consultancy, Honoraria; Heron: Consultancy, Honoraria; Tracon: Equity Ownership; Epizyme: Equity Ownership; Bristol Myer Squibb: Consultancy, Honoraria; Sunesis: Equity Ownership; Portola: Equity Ownership; Heron therapeutics: Equity Ownership; Cardinal health: Consultancy, Honoraria; Bristol Myer Squibb: Equity Ownership; Celgene: Equity Ownership; Spectrum pharmaceutical: Equity Ownership; Astrazeneca: Equity Ownership; Seattle genetics: Equity Ownership; Roche: Consultancy, Honoraria. DeZern:Astex Pharmaceuticals, Inc.: Consultancy; Celgene: Consultancy. Foran:Agios: Honoraria, Research Funding. Gore:Celgene Corporation: Consultancy, Research Funding. Komrokji:DSI: Consultancy; Agios: Consultancy; Novartis: Speakers Bureau; JAZZ: Speakers Bureau; pfizer: Consultancy; celgene: Consultancy; Incyte: Consultancy; JAZZ: Consultancy. Maciejewski:Alexion: Consultancy; Novartis: Consultancy. Starczynowski:Kurome Therapeutics: Consultancy. Sekeres:Millenium: Membership on an entity's Board of Directors or advisory committees; Syros: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees.

Background Myelodysplastic syndromes (MDS) are a collection of hematopoietic disorders with widely variable prognoses and treatment options. Pathologic diagnosis can be challenging and misdiagnosis can impact patient therapy and outcome. How commonly misdiagnosis occurs, and the severity of diagnostic errors, is not known. Here, we report interim analyses of patients (pts) with cytopenia and suspected MDS from the NHLBI National MDS Natural History Study (https://thenationalmdsstudy.net ClinicalTrials.gov: NCT02775383) assessing MDS occurrence and rates of agreement on classification of MDS/MDS-related disorders by local and centralized review. Methods Pts with cytopenias and clinically suspected MDS were identified between 6/16 and 6/18 from 84 participating centers in this ongoing multi-Institutional Cooperative Group study, with a goal of recruiting 2000 MDS (WHO 2016 subcategories), MDS/MPN or low blast count acute myeloid leukemia (AML, Results Of 375 pts for whom data and samples were submitted with completed classification, 88 (23%) had MDS, 15 (4%) MDS/MPN, 12 (3%) ICUS, 23 (8%) AML, and 237 (63%) other cytopenias (Figure 1). The median age of all pts was 71 years (range, 20-92), 44% were female, and median baseline blood counts and other baseline measures are in Figure 2. MDS pts had single lineage dysplasia (SLD, 0), SLD with ring sideroblasts (RS, 9 (10%)), multi-lineage dysplasia (MLD, 17 (19%)), MLD -RS (18 (20%)), excess blasts I (EB, 14 (16%)), EBII (19 (22%)), del(5q) (6 (7%)), and MDS-U (5(6%)). IPSS-R categories were defined in 51 of 88 MDS cases (58%): Very Low (27%), Low (43%), Intermediate (27%), High (16%), and Very High (14%). Overall site/central agreement on diagnosis occurred in 225 cases (60%) with inconsistency associated with recognized site coding errors resolved in 54 cases (14%) without 3rd party review. Seventy-eight others (21%) were referred to 3rd level review; confirmation of CL/B classification occurred in 49/78 cases (63%), agreement with site in 13/78 (17%), and a different diagnosis in 16/78 (21%). Clinically meaningful changes in diagnoses between local and central review occurred 26% of the time (Figure 1, n=97/375 kappa =.53 95% CI (.45, .61)). Site assigned MDS was changed to ICUS or other cytopenia in 35% (n=34/99); and to AML in 3% (n=3/99). For cases with site assignment to other causes of cytopenias (225 of 375 cases, 60%), central assignment identified ICUS in 3, MDS/MPN overlap in 8, AML in 2 and MDS in 22, totaling a change in diagnosis in 16%. Of note, 60% (15/25) of ICUS diagnosed locally were interpreted as reactive marrow or normal according to central review. Within MDS cases diagnosed locally, the greatest discrepancy was observed in the MDS-U classification, reported 31 times (31/99 31%) but confirmed in only 2 cases (6%), with 22 (71%) found to not have MDS. Across the study when compared to local assignment, central review changed the follow-up cohort assignment for 87 pts (23%). Conclusions In this well-characterized series of pts evaluated for MDS with bone marrow biopsy and paired site/central morphologic assessment, 40% of site diagnoses were changed at central review and site coding errors were common. In 26%, the changes were clinically meaningful, potentially affecting patient treatment and prognosis. In particular, site designation of MDS-U was an unreliable classification category, which could only partially be attributed to miscoding errors at the local site. Incorporating genomics data might help refine MDS diagnoses. Disclosures Bejar: Genoptix: Consultancy; Takeda: Research Funding; Celgene: Consultancy, Honoraria; Modus Outcomes: Consultancy; Astex/Otsuka: Consultancy, Honoraria; AbbVie/Genentech: Consultancy, Honoraria; Foundation Medicine: Consultancy. Komrokji:Novartis: Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Celgene: Honoraria, Research Funding; Novartis: Honoraria, Speakers Bureau; Celgene: Honoraria, Research Funding; Novartis: Honoraria, Speakers Bureau. Scott:Agios: Consultancy; Novartis: Research Funding; Celgene: Consultancy, Research Funding; Alexion: Consultancy. Gore:Celgene: Consultancy, Research Funding. Sekeres:Opsona: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Opsona: Membership on an entity's Board of Directors or advisory committees.

Abstract 1660 GSEA (gene-set enrichment array) analysis for expression levels in acute myeloid leukemia (AML) blasts of hoxA9/meis1, has afforded additional prognostic capacity to cytogenetically-defined subtypes. Signaling pathway (KEGG, GO, Ingenuity) analysis of Affymetrix gene expression data has also been used to predict prognosis of AML patients, identifying an adverse high MAPK gene signature. Genome-wide epigenetic (DNA methylation) profiling has added to AML prognostication. We analyzed patient prognosis and in vitro sensitivity for blasts by pathway-targeting agents, in relation to expression clusters defined by the results of GSEA profiling. Blast cell sensitivity was assayed using the agents: (Tyrosine kinase inhibitors for: Flt3: Sorafenib (Onyx/Bayer) and Syk/Flt3: R406 (AstraZeneca); Bortezomib (Millenium), a proteasome- and NFkB- inhibitor, inducer of endoplasmic reticulum (ER) stress; or the pan-histone deacetylase (HDAC) inhibitor, SBHA, Vorinostat analogue). A group of 70 AML cases was studied. GSEA's (Taqman/RQ-PCR, ABI) were performed on two different 31-gene platforms interrogating the interaction of tyrosine kinase survival pathways (eg. Flt3) with downstream epigenetic targets: tumor suppressor genes DAPK1, p16INK4a/CDKN2A, and RUNX3. Expression levels of these are responsive to input from c-jun/AP-1, non-canonical NFkB isoforms/HDAC's, polycomb genes, and ets/ERG, which were monitored. Analysis of overall patient survival (OS) by Kaplan-Meier plots revealed conformity with established outcomes for conventional cytogenetic categories. Also, poor-risk categories defined by normal karyotype Flt3ITD mutation, as well as high hoxA9 and meis1 expressions were recognized. Classification categories involving NKFlt3ITD/high hoxA9/meis1 or complex cytogenetics/high MAPK were most strictly separated by Kaplan-Meier curves, and by representation on the GSEA heatmaps, vs. CBF/PML-RAR translocations. Specific association, between repression of the tumor suppressor DAPK1 (normalized to c-jun, a transcriptional activator) with high expressions of hoxA9 and DAPK1-repressive, non-canonical NFkB/relB, was apparent in most NKFlt3ITD and tMLL cases. Also, a known functional interaction implicating high Id1 expression with its repression of p16INK4a(CDKN2A) was linked by their expression levels on GSEA. The DAPK1/CDKN2A clusters demonstrated significant overlap, often with additional RUNX3 repression. The DAPK1-repressed(R) clusters demonstrated independent prognostic importance. There was median OS for DAPK1-R cluster #1(lower MAPK signature) of 17 months vs. for DAPK1-R cluster #2 of 6 months. This latter cluster was described by higher MAPK signature evidenced by heightened transcript levels of BRCA1 [Bullinger et al. Blood, 2007], FoxM1, bcl-2, IL-1b. The dominant cytogenetic/molecularly-defined phenotypes represented in these DAPK1-R clusters were NKFlt3ITD+ve and tMLL. A very-high MAPK/complex cluster, evidenced median OS 4.5 months vs. good prognosis (low MAPK/DAPK1, and low hoxA9/meis1) group: median OS> 3 years. Interestingly, in vitro activity for the dual inhibitor R406 on blasts was greatest in the category with strongest repression of both p16INK4a/CDKN2A and DAPK1, and with lowest expression of syk transcripts (10-fold compared with high patient values), with a median IC50 of between 10 nM (tMLL)-100nM (Flt3ITD). By contrast, Sorafenib demonstrated its greatest activity in a high MAPK phenotype, including but not restricted to Flt3ITD+ve status. Bortezomib demonstrated median IC50 40 nM. However, high expression levels of FoxM1, putative Bortezomib target, were negatively-associated with its activity. SBHA, the HDAC inhibitor, demonstrated lower activity on a molar basis, but had important synergy with tyrosine kinase inhibitors, a property that was optimal in the context of Id1 hyperexpression. Bortezomib was strongly synergistic with Flt3/syk inhibitors, particularly on FltITD+ve blasts. Indeed, both Bortezomib and the HDAC inhibitor demonstrated by correlation analysis (coefficients=63.3 and 13.4, respectively) optimal activities with Id1 hyperexpression. In conclusion, a pathway-focused genetic and epigenetic prognostic classification that also reports targeting agent sensitivity was established and further validated in a phase I (Sorafenib/Vorinostat) trial in AML (H Sayar, these abstracts). Disclosures: Sayar: Onyx/Bayer: Research Funding.