ALBERT

Description: There is increasing evidence that deranged metabolism is an important mechanism of cancer pathogenesis. We conducted multiple genomic analyses of publicly available acute myelogenous leukemia (AML) data sets that revealed a critical role for one carbon and nucleotide metabolism, particularly mitochondrial, in a subset of AML samples. One carbon metabolism is a complex series of pathways involving several amino acids, the synthesis of purines, thymidylate, S-adenosylmethionine, and the support of cellular methylation reactions. SHMT2, MTHFD2, and MTHFD1L are the major enzymes functional in the one carbon folate pathway in the mitochondria. MTHFD2 is a NAD-dependent, mitochondrial methylenetetrahydrofolate dehydrogenase and cyclohydrolase, derived from a similar trifunctional cytoplasmic protein. In the mitochondria, the formyltetrahydrofolate synthetase activity is performed by MTHFD1L. We noted that these enzymes are downregulated with suppression of MYC. Gene set enrichment analysis (GSEA) of cell lines treated with JQ1, a small molecule BET bromodomain inhibitor which suppresses MYC, showed a significant enrichment in genes of the one carbon pool by folate KEGG pathway. We show that treatment of AML cells with JQ1 causes a decrease in MTHFD2 and MTHFD1L levels. This is recapitulated with knockdown of MYC with four shRNAs in multiple AML cell lines. Analysis of ENCODE ChIP-Seq data revealed MYC binding at SHMT2, MTHFD2 and MTHFD1L promoters, which we confirmed with ChIP-qPCR in human AML cell lines. Moreover, Independent component analysis (ICA) of primary AML samples in The Cancer Genome Atlas (TCGA) showed a significant correlation between high MTHFD2 and high MYC expression and a metabolic gene expression signature. MTHFD2 is differentially expressed in transformed and non-differentiated cells, and is thus an attractive drug target given its limited expression in normal tissues. Knockdown of MTHFD2 with four shRNAs in five AML cell lines caused a decrease in cell proliferation as measured by BrdU incorporation and a decrease in colony formation in methylcellulose. MTHFD2 knockdown also induced myeloid differentiation, as measured by Cd11b expression, morphologic changes and induction of a previously validated AML differentiation gene expression signature. AML cells transduced with MTHFD2-directed shRNAs demonstrated attenuated growth in an orthotopic mouse model of AML at day 15 post-injection. We next deployed a doxycycline inducible shRNA system to demonstrate that shRNAs directed against MTHFD2 cause a decrease in AML burden in mice with established disease as measured by bioluminescence with an increase in survival. Metabolite profiling is currently underway to further elucidate the metabolic consequences of MTHFD2 loss in AML. In summary, in silico analyses of primary patient AML data sets revealed a subset of AML samples enriched for a metabolic gene expression signature. We demonstrate that MYC is a regulator of the one carbon folate pathway, modulating expression of SHMT2, MTHFD2 and MTHFD1L. In vitro and in vivo data strongly supports a critical role for MTHFD2 in AML pathogenesis and its potential as a new target for AML therapy. Disclosures: No relevant conflicts of interest to declare.

Description: Background: Detailed population-based clinical characteristics and outcomes of chronic lymphocytic leukemia (CLL) and small lymphocytic leukemia (SLL) are scarce. We have previously demonstrated in the province of Manitoba that by combining population-based sources of a cancer registry and a centralized flow cytometry database, the incidence of CLL/SLL is much higher than previously reported. We have now examined the clinical characteristics of this large and well defined patient group. We hypothesized that the clinical features of these patients (pts) may differ from previous studies where data was obtained from referral centers. Methods: All pts from the Manitoba Cancer Registry with ICD codes 9 & 10 for CLL or SLL from 01/01/1998 to 12/31/2003 were identified. Pts from the flow cytometry database during this time period with a diagnosis of CLL/SLL were also identified. A retrospective electronic chart review was conducted. The two databases were compared and analyzed. Results: 715 pts with CLL were identified. 358 pts were identified from the cancer registry alone, 136 pts by the flow cytometry database, and 221 pts in both datasets. Overall, the age-adjusted annual incidence rate of CLL/SLL in Manitoba was 10.5/105 (95% C.I. 9.4–12.7/105). Median age of all pts was 72yrs (19–101). Only 71 pts (9.9%) were aged

Description: Introduction: The prognosis of patients (pts) with relapsed or refractory (rel/ref) Chronic Lymphocytic Leukemia (CLL) is poor. AT7519M is a small molecule inhibitor of cyclin-dependent kinases (CDKs) 1, 2, 4, 5 and 9 with lower potency against CDKs 3, 6 and 7. AT7519 has potent anti-proliferative activity against peripheral blood mononuclear cells isolated from CLL patients. Exposure of CLL cells to AT7519 results in cell cycle arrest and, ultimately, cell death by apoptosis. Based on the results of a NCIC CTG phase I study in advanced malignancies, the recommended phase II dose (RP2D) was 27 mg/m2 given as a 1 hour infusion twice weekly for 2 out of every 3 weeks. Using this schedule, Tumor Lysis Syndrome (TLS) and QTc prolongation were not observed. Methods: In a phase II clinical trial, we evaluated the clinical and pharmacodynamic effects of AT7519 using the RP2D schedule in pts with rel/ref CLL. Eligible patients were those with documented CLL with at least one prior systemic treatment regimen and either lymphocyte count 〉 10 x 109/L or at least one measurable lymph node 〉 2 cm x 2 cm. The primary objective was complete or partial remission (CR/PR) as defined by the 2008 International Working Group (IWG) Guidelines. We used a Fleming Phase II design, aiming for a total of 30 subjects, assuming an HA of 〉0.20. Cycle 1, dose 1 was administered as an in-patient with prophylaxis and monitoring for TLS. Results: Seven pts were accrued over 16 months. As a result, the trial was prematurely closed. Reasons for slow accrual included concerns about the risk of TLS, the need for in-patient care during cycle 1, and the relative stringency of eligibility criteria regarding baseline hematopoietic and renal function. All seven pts were male, with median age 70 years (range 47-81). Median number of previous regimens was 3 (range 1-4). Two pts had 11q- and one had 17p-. A total of 21 cycles were administered (median 4 cycles) with 71% of patients receiving 〉 90% of the planned dose intensity. Two pts required a dose reduction due to thrombocytopenia and one of these patients came off study early due to hypoxia and fever. The most common non-hematologic adverse events that were at least possibly related were grade 1 and 3 fatigue, grade 1 nausea (57%), grade 1 diarrhea and grade1/2 anorexia (43%) and grade1/2 fever (29%). Hematologic toxicities were primarily grade 1 and 2. One pt developed grade 4 neutropenia and grade 3 thrombocytopenia on cycle 1 day 2; a second patient developed grade 3 thrombocytopenia on C1D2. Both required dose reductions and counts recovered. Biochemical toxicity was minimal; all grade 1 except one pt with transient grade 2 bilirubin and 2 pts with grade 2 hypophosphatemia. According to the protocol defined 2008 IWG response assessment criteria, there were no responses observed. Four pts had stable disease (SD), two pts had progressive disease (PD) and one pt was inevaluable (came off due to toxicity after 2 doses). However, updated response criteria for CLL recommend that lymphocytosis alone should not be considered evidence of progressive disease in clinical trials testing novel agents that affect cellular migration and adhesion. Based on these new criteria, 1 of 7 patients developed PD, 3 demonstrated tumor shrinkage at time of coming off protocol therapy including 2 with corresponding improvement in blood counts although none achieved objective partial response (see Table). Conclusion: The CDK inhibitor, AT7519M was safely administered to pts with rel/ref CLL. While some patients had tumor shrinkage, there were no objective responses over the course of this study. Unfortunately, the small sample size of this trial precluded any other definitive conclusions. Table: Responses Graded By Traditional and Revised CLL Response Criteria Table:. Responses Graded By Traditional and Revised CLL Response Criteria Disclosures Toguchi: Astex Pharmaceuticals, Ltd: Employment. Lyons:Astex Pharmaceuticals: Employment.

Description: Background:We previously conducted a population-based study on chronic lymphocytic leukemia (CLL) in Manitoba, which showed that second cancers are twice as common and skin cancers eight times as common in this disease, as compared to an age- and sex-matched control population and patients with follicular lymphoma. It is postulated that this is related to immunosuppression, secondary to the disease and chemo-immunotherapy. Here we set out to investigate rates and types of skin cancers in CLL patients and how these influence the outcome of CLL patients. Methods: Newly diagnosed CLL patients attending the CancerCare Manitoba CLL Clinic from the January 1st, 2002 until December 31st, 2012 were selected for this study. Patients were followed until December 31, 2014. Cox Proportional Hazard models were constructed to predict hazard's ratios (HR) and 95% confidence intervals (95% CI) for survival as well as risk of non-cutaneous malignancies. Association between skin cancer and CLL prognostic markers were investigated by Fisher's Exact test, Student's t-test and logistic regression analysis. P-value

Description: Alterations in differentiation pathways contribute to the development of acute myeloid leukemia (AML). Differentiation therapy with all-trans retinoic acid (ATRA) has dramatically altered the treatment of acute promyelocytic leukemia, transforming it from a nearly fatal disease to a curable one. We set out to identify cellular pathways that contribute to AML differentiation, with the goal of identifying new therapeutic targets. We analyzed gene expression data from AML cell lines treated with phorbol 12-myristate 13-acetate (PMA), ATRA, Vitamin D, the BET inhibitor JQ1 and the DOT1L inhibitor EPZ00477, treatments known to induce AML differentiation and impair growth. Folate-mediated one-carbon metabolism was one of only three metabolic pathways altered by these compounds, with expression of MTHFD2 consistently downregulated with each compound. MTHFD2 is an NAD-dependent, bi-functional mitochondrial methylenetetrahydrofolate dehydrogenase and cyclohydrolase. It is differentially expressed in embryonic and transformed tissues and is upregulated in myeloid progenitors. MTHFD2 is the most differentially expressed metabolic enzyme in cancer cells versus normal cells, including normal proliferating cells. We thus investigated the role of MTHFD2 in myeloid malignancy. First, we demonstrated using ChIP-qPCR, MYC knockdown and MYC inhibition with a BET inhibitor, that MYC directly regulates MTHFD2 expression in AML. Knockdown of MTHFD2 with two shRNAs confirmed to have on-target activity, induced myeloid differentiation in AML cell lines, as measured by Cd11b expression, morphologic changes and induction of a previously validated AML differentiation gene expression signature. MTHFD2 knockdown decreased cell growth in AML cell lines, as well as decreased colony formation in methylcellulose in both AML cell lines and primary patient blasts. AML cells transduced with these two MTHFD2-directed shRNAs demonstrated attenuated growth in an orthotopic mouse model of AML. Furthermore, three MTHFD2-directed shRNAs prolonged survival in an MLL-AF9 mouse leukemia model. Additionally, using a doxycycline inducible shRNA system, we demonstrated that two miR30-shRNAs directed against MTHFD2 decreased AML burden in mice with established disease and prolonged survival. To identify biomarkers of response to MTHFD2 suppression, we used single sample Gene Set Enrichment Analysis (ssGSEA) to identify primary patient AML samples enriched for gene expression signatures of folate-mediated one-carbon metabolism and MTHFD2. We found in both independent data sets that the cluster of patients enriched for expression of the one-carbon folate pathway gene signatures was also enriched for patients with FLT3-ITD mutations, a subset of AML with a particularly poor prognosis. In addition, in an shRNA screen targeting 11,194 genes and performed in 216 cancer cell lines, including 17 AML lines, FLT3-ITD was a biomarker of response to MTHFD2 knockdown. We next validated that while MTHFD2 suppression induced measureable differentiation in all six AML cell lines examined, it induced the most robust induction of apoptosis in FLT3-ITD mutant AML. The mitochondrial one-carbon folate pathway is thought to contribute to cellular oxidative balance by providing reducing power in the form of NAD(P)H, and suppression of MTHFD2 was previously shown to increase ROS levels. Indeed, suppression of MTHFD2 led to a marked increase in ROS in the FLT3-ITD positive AML cell lines in which apoptosis was induced. In summary, a decrement in MTHFD2 expression was found at the center of multiple AML perturbations that impair AML growth and induce differentiation. Our data support MTHFD2 as an AML dependency and FLT3-ITD as a potential biomarker of response. We thus provide critical preclinical evidence for targeting of MTHFD2 as a therapeutic strategy in AML. Disclosures Stone: Celgene: Consultancy; Merck: Consultancy. DeAngelo:Celgene: Consultancy; Pfizer: Consultancy; Incyte: Consultancy; Agios: Consultancy; Novartis: Consultancy; Ariad: Consultancy; Bristol Myers Squibb: Consultancy; Amgen: Consultancy. Stegmaier:Novartis Pharmaceuticals: Consultancy.

Description: BACKGROUND: The study of rare diseases is limited by the uncommon nature of the conditions as well as the widely dispersed patient populations. Current rare disease registries such as the National Organization of Rare Diseases utilize centralized platforms for data collection; however because of their broad nature, these do not always capture unique, disease specific elements. Hairy Cell Leukemia (HCL) is a rare leukemia globally with approximately 900 new cases diagnosed in the US each year. The HCL Foundation undertook creation of a Patient Data Registry that collects data from multiple HCL Centers of Excellence (COE) around the globe to better understand the complications, treatment outcomes, disease subtypes, comorbid conditions, epidemiology, and quality of life of patients with HCL. METHODS: Investigators at The Ohio State University Department of Biomedical Informatics and Division of Hematology in collaboration with the HCL Foundation developed a Patient Data Registry (PDR) for the longitudinal capture of high quality research data. This system differs from other registries in that it uses a federated( rather than centralized) architecture, wherein data is queried and integrated in an on-demand manner from local registry databases at each participating site. Further, the data collected for use in the registry combines both automated exports from existing electronic health records (EHRs) as well as additional data entered via a set of web-based forms. All manually entered data comes from source documents, and data provenance spanning electronic and manually entered data is maintained via multiple technical measures. Patients may be enrolled at HCL COE, or, if they do not have access to a COE they may enroll via a web-based portal (www.hairycellleukemia.org). At this time due to regulatory requirements the web-based portal is available to US patients only. All data are de-identified (see Figure 1: De-Identification Workflow) which reduces regulatory burden and increases opportunities for data access and re-use. End users have access to data via a project-specific query portal. RESULTS: The Patient Data Registry has been deployed at The Ohio State University, Royal Marsden Hospital, and MD Anderson Cancer Center, and is undergoing deployment at the University of Rochester. Up to 25 international HCL COE may participate. In addition, US patients are actively entering the registry via the web-based portal. To date, 227 patients have been consented to the registry with 119 of these being via the web-based entry point. CONCLUSION: We created an international and web-based patient data registry which will enable researchers to study outcomes in HCL in ways not previously possible given the rarity of the disease. This work was made possible by research funding from the Hairy Cell Leukemia Foundation. Figure De-Identification Workflow Figure. De-Identification Workflow Disclosures Andritsos: Hairy Cell Leukemia Foundation: Research Funding. Anghelina:Hairy Cell Leukemia Foundation: Research Funding. Lele:Hairy Cell Leukemia Foundation: Research Funding. Burger:Pharmacyclics: Research Funding. Delgado:Gilead: Consultancy, Honoraria; Novartis/GSK: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Roche: Consultancy, Honoraria, Research Funding; Infinity: Research Funding. Jones:AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics, LLC, an AbbVie Company: Membership on an entity's Board of Directors or advisory committees, Research Funding. Lozanski:Beckman Coulter: Research Funding; Genentech: Research Funding; Stemline Therapeutics Inc.: Research Funding; Boehringer Ingelheim: Research Funding. Montserrat:Morphosys: Other: Expert Testimony; Vivia Biotech: Equity Ownership; Gilead: Consultancy, Other: Expert Testimony; Pharmacyclics: Consultancy; Janssen: Honoraria, Other: travel, accommodations, expenses. Parikh:Pharmacyclics: Honoraria, Research Funding. Park:Genentech/Roche: Research Funding; Amgen: Consultancy; Juno Therapeutics: Consultancy, Research Funding. Robak:Pharmacyclics, LLC, an AbbVie Company: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; AbbVie: Consultancy, Honoraria, Research Funding. Tam:janssen: Honoraria, Research Funding; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees. Heckler:Hairy Cell Leukemia Foundation: Research Funding. Payne:Hairy Cell Leukemia Foundation: Research Funding.

Description: Introduction: Patients with lower-risk (LR) MDS, defined as very low-, low-, and intermediate-risk by the Revised International Prognostic Scoring System (IPSS-R), have a reduced risk of progressing to acute myeloid leukemia compared with higher-risk patients, but a shortened overall survival (OS) compared with age-matched controls. MDS patients with RS have a better prognosis than those without RS, but may experience extended periods of RBC transfusion dependence. RBC transfusion dependence is associated with reduced OS in patients with LR-MDS, but studies focusing on RBC transfusion dependence and OS in RS+ MDS patients are lacking. To address this gap, data from the Canadian MDS Registry were used to assess the relationship between RBC transfusion dependence patterns and OS in this patient population. Methods: Patients with a diagnosis of RS+ MDS who were identified as transfusion dependent (TD) in the Canadian MDS Registry from 2008 to 2019 were included. Patients were considered TD if they received ≥ 1 RBC transfusion in at least one 8-week cycle. A sensitivity analysis was conducted wherein patients were considered TD if they received ≥ 1 RBC transfusion for 2 consecutive 8-week cycles. Patients were considered persistently TD (PTD) if they were TD throughout follow-up, or intermittently TD (ITD) if they were transfusion independent for periods of ≥ 8 weeks after an initial onset of TD. Covariates that were assessed included age, sex, IPSS-R risk score at enrollment, Eastern Cooperative Oncology Group performance status score at enrollment, ferritin level at first TD onset, Charlson Comorbidity Index at first TD onset, and receipt of iron chelation and anemia-treating therapies at first TD onset. Cox proportional hazards regression was used to test the association between PTD and mortality risk. Treatment patterns during follow-up were also examined. Results: Between 2008 and 2019, 191 patients had a diagnosis of RS+ MDS, of which 107 required ≥ 1 RBC transfusion over at least one 8-week cycle during follow-up. Of the 107 patients who received ≥ 1 RBC transfusion, 71 had ≥ 2 assessments for transfusion dependence and complete data on all outcomes and covariates, 36 (50.7%) of whom were classified as PTD (Table 1). Compared with ITD patients, PTD patients were older (mean age ± standard deviation [SD]: 75.11 ± 8.34 vs 69.59 ± 13.33 years) and had higher IPSS-R risk (17% of PTD patients were intermediate- or higher-risk compared with 3% of ITD patients). Median OS from first TD onset was 18.7 months (95% confidence interval [CI] 11.3-46.9) for PTD patients, compared with 48.7 months (95% CI 39.0-not evaluable) for ITD patients (Figure). After adjusting for baseline covariates, being PTD was associated with significantly greater mortality risk than being ITD (hazard ratio [HR] 2.24, 95% CI 1.18-4.25). Similar results were observed for the sensitivity analysis requiring ≥ 1 RBC transfusion for 2 consecutive 8-week cycles prior to the onset of TD (HR 2.18, 95% CI 1.13-4.21). Compared with ITD patients, PTD patients were less likely to receive iron chelation therapies (42% vs 54%), erythropoiesis-stimulating agents (25% vs 40%), and lenalidomide (14% vs 20%) during follow-up (Table 2). Conclusions: In this study, we extracted Canadian MDS Registry data on RBC transfusions and OS for MDS patients with RS+ MDS. More than half (50.7%) of the identified cohort became TD during follow-up. Among those who received RBC transfusions, PTD patients had significantly shorter OS and increased mortality risk compared with ITD patients, and RBC transfusion dependence independently predicted inferior outcomes. These conclusions are consistent with previous findings on the relationship between RBC transfusions and OS in all patients with LR-MDS. Disclosures Buckstein: Takeda: Research Funding; Celgene: Consultancy, Honoraria, Research Funding. Keating:Celgene: Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria; Seattle Genetics: Consultancy; Janssen: Membership on an entity's Board of Directors or advisory committees; Shire: Membership on an entity's Board of Directors or advisory committees; Hoffman La Roche: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees. Leber:Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Astellas: Honoraria, Membership on an entity's Board of Directors or advisory committees; Jazz: Honoraria, Membership on an entity's Board of Directors or advisory committees; Alexion: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Sabloff:Pfizer Canada:: Honoraria, Membership on an entity's Board of Directors or advisory committees; Jazz Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi Canada: Research Funding; Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees; ASTX: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Astellas Pharma Canada: Honoraria, Membership on an entity's Board of Directors or advisory committees; Actinium Pharmaceuticals, Inc: Membership on an entity's Board of Directors or advisory committees. Leitch:Novartis: Honoraria, Research Funding, Speakers Bureau; Otsuka: Honoraria; Alexion: Research Funding; AbbVie: Research Funding; Celgene Corporation: Honoraria, Research Funding. St. Hilaire:Celgene: Honoraria, Research Funding; Novartis: Honoraria, Research Funding. Finn:Takeda: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Ipsen: Membership on an entity's Board of Directors or advisory committees; Lundbeck: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Boehringer Ingelheim: Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck: Research Funding; Alexion: Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees. Yee:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Astex: Research Funding; Hoffman La Roche: Research Funding; MedImmune: Research Funding; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck: Research Funding; Millennium: Research Funding; Astellas: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees. Banerji:Janssen: Consultancy, Honoraria, Research Funding; Research Manitoba: Research Funding; CAPhO: Honoraria; BIOGEN: Other: Licensing fee; CancerCare Manitoba/University of Manitoba: Employment; CIHR: Research Funding; Dana-Farber Cancer Institute: Other: Licencing fee; CCMF: Research Funding; Abbvie: Consultancy, Honoraria; Gilead: Consultancy, Honoraria, Research Funding; Astra-Zeneca: Consultancy, Honoraria; LLSC: Research Funding; Roche: Honoraria, Licensing fee, Research Funding. Liu:Celgene Corporation: Employment. Tang:Celgene Corporation: Employment, Equity Ownership. Westcott:Celgene Corporation: Employment, Equity Ownership. Huang:Celgene Corporation: Employment. Wang:Cornerstone Research Group: Employment. Cameron:Cornerstone Research Group: Employment, Equity Ownership. Morison:Celgene Corporation: Employment. Spin:Cornerstone Research Group: Employment.

Description: Background: Health-Related Quality of life (HRQoL) is diminished in patients with myelodysplastic syndrome (MDS). We have previously shown that HRQoL remains stable over time and low hemoglobin, transfusion dependence (TD) and age 〉 65 years impact QoL1. Here, we present an updated larger data set with longer follow up and consider the impact of baseline characteristics and treatments received on patient-related outcomes. Methods: MDS-CAN is a prospective database active in 15 centers across Canada, enrolling patients since April 2012. In addition to disease and patient-related characteristics, we measure HRQoL at baseline and every 6 months using the EORTC-QLQ-C30, EQ-5D, and a global fatigue scale (GFS). We examined the impact of disease related factors (IPSS, IPSS-R, karyotype, TD), patient factors (ECOG, age, gender, co-morbidity (Charlson index), frailty (Rockwood scale), disability (Lawton-Brody Independent Activities of Daily Living), and treatments received at any time (azacitidine (AZA), lenalidomide, erythropoietin-stimulating agents (ESA), iron chelation) on QoL scores. AZA-treated patients were divided into responders (where documented) or deriving benefit (if 〉 6 cycles) vs. non-responders. Wilcoxon rank-sum or Kruskal-Wallis nonparametric tests were used to compare scores among subgroups. Changes in QoL were assessed with a linear mixed model to account for time- dependent covariates such as TD, risk scores and treatment. Results: 594 patients were enrolled a median of 2.2 months post diagnosis (IQR: 0.8, 4.8) with a median age of 73 years , 63% male gender and performance status (ECOG) of 0-1 in 90%. IPSS scores were low/int-1 in 73% and IPSS-R scores were very low (9%), low (30%), intermediate (27%), high (20%) and very high (14% of patients). 31% were transfusion dependent at enrolment. Treatments received at any time included AZA (38%), lenalidomide (9.8%), ESA (35%) and iron chelation (12%). At a median follow up of 17 months, 329 patients (55%) died with cause of death reported as AML in 22%. Baseline assessment: Mean EQ-5D global score for the cohort was 0.75 ± 0.25 and did not significantly change over time (Figure 1). Patients with high IPSS, high/very high IPSS-R, TD, lower hemoglobin, higher ECOG, increased comorbidity, frailty and disability were more likely to have lower EQ-5D/QLQ C30 scores (inferior QoL) and higher fatigue (GFS). Age was not significantly related to QoL. Interestingly, female gender was associated with inferior QoL by EQ-5D and GFS (Figure 2). Patients scoring in the lowest quartiles for physical performance tests (grip, 4 metre walk and 10x chair sit-stand tests) also had inferior QoL scores. QoL over time: By linear mixed modelling, we did not find significant differences in QoL over time in patients treated with or without AZA, lenalidomide, or ESAs measured by the EQ-5D instrument. Iron chelation was associated with lower scores (p=0.003) although this may simply be a surrogate for transfusion dependence which is associated with inferior QoL. AZA responding/deriving benefit patients had higher QoL scores from baseline and decreased fatigue compared with those not responding or not deriving benefit (Figure 3) measured by the QLQ-C30 and GFS instruments. Patients with the highest IPSS/IPSS-R risk groups had significantly inferior QoL over time. In conclusion, this study demonstrates that HRQoL remains fairly stable over time in MDS and implementation of treatment is not at the detriment of patient related outcomes. Patients treated with AZA who respond or remain on drug for 〉 6 months maintain higher QoL scores over time. Disease (IPSS, IPSS-R, hemoglobin, transfusion dependence) and patient-related factors (ECOG, gender, comorbidities, disability, frailty) are associated with reduced HRQoL. The prospective assessment of QoL using a validated MDS-specific QoL instrument (QUALMS) and disease course is underway. 1 Buckstein, R., Alibhai, S.M., Lam, A., et al. The health-related quality of life of MDS patients is impaired and most predicted by transfusion dependence, hemoglobin and age. Leukemia Research. May 2011 Vol 35, Supplement 1, Pages S55-56. Disclosures Wells: Alexion Pharmaceuticals, Inc.: Honoraria, Other: Travel Support , Research Funding; Novartis: Honoraria; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees. Geddes:Alexion: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding. Zhu:Janssen: Consultancy; Novartis: Consultancy; Celgene: Consultancy, Research Funding. Sabloff:Celgene: Membership on an entity's Board of Directors or advisory committees. Keating:Bayer: Honoraria, Membership on an entity's Board of Directors or advisory committees. Leber:Novartis Canada: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis Canada: Honoraria, Membership on an entity's Board of Directors or advisory committees. Leitch:Novartis: Honoraria, Research Funding, Speakers Bureau; Celgene: Honoraria, Research Funding; Alexion: Honoraria, Research Funding; AbbVie: Research Funding. Yee:Celgene, Novartis, Otsuka: Membership on an entity's Board of Directors or advisory committees; Agensys, Astex, GSK, Onconova, Genentech/Roche: Research Funding. St-Hilaire:Novartis: Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees. Shamy:Amgen: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Elemary:Roche: Membership on an entity's Board of Directors or advisory committees; Lundbeck: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding. Delage:Celgene: Membership on an entity's Board of Directors or advisory committees; AbbVie: Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Research Funding; BMS: Membership on an entity's Board of Directors or advisory committees, Research Funding. Rockwood:Pfizer: Research Funding; Lundbeck: Membership on an entity's Board of Directors or advisory committees; CHIR: Research Funding; Nova Scotia Health research foundation: Research Funding; Sanofi: Research Funding; Capital Health research support: Research Funding; Canadian consortium on neurodegeneration in aging and nutricia: Membership on an entity's Board of Directors or advisory committees; Alzheimer Society of Canada: Research Funding; Foundation Family Fund: Research Funding. Banerji:Teva: Other: Unrestricted grant received in the past; Gilead: Other: Unrestricted grant received in the past; Abbvie: Other: Unrestricted grant received in the past; Roche: Other: Unrestricted grant received in the past; Janssen: Other: Unrestricted grant received in the past. Buckstein:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Description: Background:Chronic lymphocytic leukemia (CLL) is the most prevalent leukemia in North America with the majority of patients being over the age of 70 (Goede et al, 2014). CLL is a heterogeneous disease with some patients undergoing treatment at time of diagnosis, while others follow along a more indolent, asymptomatic course. When indicated, the choice of treatment is based on the patient's functional status, renal function and other comorbidities (Shanafelt, 2013). Previous studies have shown that unfit patients treated with Obinutuzumab plus Chlorambucil have shown prolongation of progression free survival and higher rates of complete response compared to other monoclonal based regimens (Goede et al, 2014). The aim of this study is to investigate the clinical use and uptake of Obinutuzumab in combination with Chlorambucil in a Canadian based population. Methods:All patients receiving Obinutuzumab were identified using the CLL CAISIS database. Then a retrospective chart review was conducted for patients approved for first-line antibody treatment with Obinutuzumab from January 1, 2014 to December 31, 2017. Data including patient characteristics, patterns of treatment, reported toxicities, response rates and survival data were collected and analyzed. This data was used to determine the overall safety and efficacy of this treatment regimen. Results: There were a total of 66 patients that met the inclusion criteria for this study. This cohort consisted of 54.5% males and 45.5% females, with a median age at diagnosis of 68 years (range: 46-94). Within this population 47 patients underwent florescence in situ hybridization testing, which identified 32 patients with chromosomal abnormalities. The immunoglobulin heavy chain variable region gene mutation was also tested in 41 patients, and identified 22 patients that were unmutated. At the time of treatment the median age was 73 (range: 55-98) with a median Cumulative Illness Rating Scale (CIRS) score of 8 (range: 3-15). Of the 66 patients who started treatment with Obinutuzumab, 50 patients (76%) achieved a partial response and 5 patients (8%) had no response. Of note, 21 patients (31.8%) discontinued treatment prior to completion of all six cycles due to cytopenias (4), other comorbidities (4), progression of CLL (2), decline in functional/mental status (2), patient request (2) and other (7). In regards to their treatment there was a high incidence of infusion related reactions (IRRs) on the first day of treatment, with 30 patients (45.5%) requiring intervention. There was a subset of 15 patients that had received low dose Chlorambucil prior to treatment with Obinutuzumab which resulted in a lower average lymphocyte count (38.1) and lower rate of IRRs (33%) compared to those with no prior Chlorambucil (average lymphocyte count: 66.5, rate of IRR: 42%). Due to toxicity and tolerability of Chlorambucil, dose reduction was observed in 37 patients (56%) throughout all six cycles of treatment. In the end, only 18 patients (27.3%) received all doses of Obinutuzumab and Chlorambucil while 37 patients (56%) received all doses of Obinutuzumab. Within the entire cohort, 12 patients have relapsed and 9 of these patients have required additional therapy. This relapse rate can be attributed to lack of response to Obinutuzumab (3), a 17p del (1), poor prognostic markers (5), and inadequate Obinutuzumab (1). Conclusion:In this current study, our results demonstrate that the majority of patients in this cohort were able to complete treatment with Obinutuzumab. Although our demographics were similar to previous studies, we found higher partial response rates (76%) likely due to differences in standards of practice, such as imaging studies after treatment. Disclosures Whiteside: Roche: Membership on an entity's Board of Directors or advisory committees, Other: teaching sessions. Dawe:AstraZeneca: Membership on an entity's Board of Directors or advisory committees; Merck: Membership on an entity's Board of Directors or advisory committees. Johnston:Roche: Other: unrestricted grant received in the past; Abbvie: Other: unrestricted grant received in the past; Teva: Other: unrestricted grant received in the past; Gilead: Other: unrestricted grant received in the past; Janssen: Other: unrestricted grant received in the past. Banerji:Roche: Other: Unrestricted grant received in the past; Janssen: Other: Unrestricted grant received in the past; Abbvie: Other: Unrestricted grant received in the past; Gilead: Other: Unrestricted grant received in the past; Teva: Other: Unrestricted grant received in the past.

Description: Hereditary xerocytosis (HX) is a rare form of hemolytic anemia with autosomal dominant inheritance in which iron loading is a prominent feature. The mutated gene causing HX has been identified as FAM38A, which codes for the PIEZO1 protein, a mechanosensitive ion channel [1].The phenotype and genotype of HX has been characterized in a large Canadian family with members spanning three generations and seven decades[2]. Affected family members demonstrate fully-compensated hemolytic anemia (average reticulocyte count 9.9%, hemoglobin 135g/L) and their red cells exhibit decreased levels of osmotic fragility. Despite elevated reticulocyte counts and elevated unconjugated bilirubin levels, serum lactate dehydrogenase levels are normal, suggesting that little if any of the erythropoiesis is ‘ineffective’. Affected family members accumulate iron with age, with average ferritin levels for adults of 478 μg/L. The mechanism behind the iron loading in HX is not known. It is now recognized that in these forms of anemia, hepcidin levels are inappropriately low for the degree of iron store, implying the presence of a mediator produced by the hematopoietic progenitors that acts on the liver to suppress hepcidin production. One pathway that appears important in regulating hepcidin synthesis is the bone morphogenetic protein (BMP)-SMAD signaling cascade. The importance of BMP6 is evident from studies using gene knockout mice. Likewise, liver-targeted knockdown of SMAD4 impairs production of hepcidin and resulted in iron overload in the mice [3]. BMP6 may act in an autocrine fashion, and its secretion by hepatocytes is upregulated in the presence of elevated iron levels. Another proposed pathway for hepcidin regulation – speculated to be involved in the erythropoietic regulation of iron – involves another cytokine also from the TGF-β superfamily. Growth differentiation factor 15 (GDF15) is expressed in high levels in placenta tissue and in smaller quantities in the liver, lungs and kidneys. It is also secreted by erythroblasts, at least in culture. Plasma levels of GDF15 are greatly increased in thalassemia and correlate with markers of erythroid mass such as the soluble transferrin receptor. Serum from thalassemic patients suppresses hepcidin mRNA expression by cultured hepatocytes, an effect partially recapitulated by recombinant GDF15, suggesting that the cytokine requires a co-factor for full hepcidin inhibition [4]. We evaluated the level of hepcidin, EPOand ferritin along with GDF15 in 29 affected individuals from a single kindred with HX, and a similar number of age matched unaffected family members to explore the putative erythropoietic regulator of iron absorption in a homogeneous genetic context. We find that ferritin level positively predicts hepcidin level (p