bluuebunny/crossref_metadata_2025 huggingface dataset:
PF397 IDENTIFICATION OF PROTEIN‐PROTEIN INTERACTIONS NECESSARY FOR MAINTENANCE OF BCR‐ABL CORE COMPLEX
Authors: Gregor T. , Bosakova M.K. , Rynes J. , Trantirkova S.F. , Mayer J. , Trantirek L. , Krejci P.
Published: June 2019

Background:

Approximately 50% of chronic myeloid leukemia (CML) patients in deep remission experience a return of clinical CML after withdrawal of tyrosine kinase inhibitors (TKIs), suggesting signaling of catalytically inactive BCR‐ABL. This allows for survival of cancer cells responsible for CML relapse after discontinuation of the TKI therapy. Elucidation of protein‐protein interactions within the BCR‐ABL signaling complex is crucial for understanding of the mechanism of residual signaling of TKI‐inhibited BCR‐ABL.

Aims:

This study aims on detailed characterization of BCR‐ABL interactions with members of its core complex, i.e. the signaling mediators Grb2, SOS1, SHC1, cCbl, CrkL, SHIP2, Sts1 and p85a.

Methods:

Peptide microarrays were used to map binding interfaces between BCR‐ABL and its interactors in high resolution. The microarray data were validated by in vivo co‐immunoprecipitation and proximity ligation assays carried out with BCR‐ABL deletion mutants and their respective interactors. Reporter assays were employed to analyze the downstream signaling of BCR‐ABL in cells.

Results:

We demonstrate that TKIs inhibit catalytic activity of BCR‐ABL, but do not completely abrogate its downstream signaling. Further, treatment with TKIs does not entirely dissolve the BCR‐ABL signaling complex consisting of Grb2, SOS1, SHC1, cCbl, CrkL and SHIP2. The interacting interfaces between BCR‐ABL and members of its core complex were mapped in high resolution. The data show that CrkL binds to proline‐rich regions located in C‐terminal, intrinsically disordered region of BCR‐ABL, that deletion of pleckstrin homology (PH) domain of BCR‐ABL diminishes interaction with SHC1, and that SHIP2 associates with the src‐homology (SH)3‐SH2‐tyrosine kinase (TK) domain of BCR‐ABL. We further demonstrate that BCR‐ABL sequence motif located in disordered region around phosphorylated tyrosine 177 mediates binding of at least three core complex members, the Grb2, SOS1 and cCbl. Introduction of Y177F substitution to BCR‐ABL blocks association with Grb2, SOS1 and cCbl, and reduces residual signaling of TKI‐inhibited BCR‐ABL.

Summary/Conclusion:

The protein‐protein interactions within the BCR‐ABL core complex were characterized in detail here. Our findings support the concept of targeting BCR‐ABL signaling in CML by inhibition of Y177 interaction interface.
PF448 EFFECTIVE STABILIZATION OF VIRAL VECTORS IN LIQUID USING AN ALGORITHM‐BASED DEVELOPMENT APPROACH
Authors: Reinauer E. , Kemter K. , Hasler J. , Rodenstein C. , Altrichter J. , Martin S.
Published: June 2019

Background:

With both the approvals of CD19 CAR‐T cell therapies and promising clinical data of gene therapy trials such as in hemophilia or sickle cell disease, recent years have seen significant progress of gene and cell therapy in the field of hematological malignancies as well as rare hematologic genetic disorders. Hence, replication‐deficient recombinant viral vectors such as adenovirus serotype 5, adeno‐associated virus and members of the poxvirus family represent a rapidly growing field of vaccine development and gene therapy.

Viral vectors are known as complex supra‐molecular ensembles of macromolecules produced by living organisms (nucleic acids, proteins, polysaccharides and in the case of lipid enveloped viruses of phospholipids) which are prone to a variety of complex chemical and physical degradation pathways, in particular due to stress induced by manufacturing, storage and distribution. This represents a significant hurdle for the development of stable vector‐based pharmaceuticals such as vaccines or gene therapeutics

Aims:

Here, we studied whether LEUKOCAREs formulation platform may also efficiently protect viral vectors in thermal stress experiments. As a representative example of viral vectors we used adenovirus serotype 5 (Ad5).

Methods:

In an algorithm‐based development approach, we used Design of Experiment (DoE) to select the most effectively stabilizing formulations for Ad5. We stored Ad5 at 37 °C and 25 °C as accelerated aging temperature to identify the most effective stabilizing excipients after short term storage as well as at 5 °C for real time storage. Based on these results, the best selected formulations were further iteratively optimized and used in long term storage at 5 °C.

Results:

By analysis of the infectious virus titers and mathematical combination of these results with the DoE matrix, the linear influence of each amino acid used in the DoE matrix was determined. The accelerated aging conditions were shown to be predictive for real‐time aging. Several of the excipients indicated a neutral influence, whereby we observed the importance of a well‐balanced combination of the components with each other regarding concentration and stabilizing interactions. The predictive potential of this approach was confirmed by two iteratively composed formulations tailored for Ad5 during long‐term storage.

Summary/Conclusion:

The pre‐selection strategy of effectively stabilizing excipients by means of an algorithm‐based development approach and the applied accelerated aging model is highly efficient and enables the generation of best‐in‐class stability formulations for Ad5 viruses and viral vectors in liquid. Moreover, this approach could have beneficial impact when applied early in downstream processing, which could enable significant reduction of viral vectors manufacturing costs for gene therapy.
PF512 NEXT‐GENERATION SEQUENCING‐BASED CLONALITY ASSESSMENT OF IMMUNOGLOBULIN GENE REARRANGEMENTS DISTINGUISHES RELAPSE FROM SECOND PRIMARY CLASSICAL HODGKIN LYMPHOMA
Authors: van Bladel D. , van den Brand M. , Rijntjes J. , Brinkman A. , Reigl T. , Darzentas N. , Hess C. , Hebeda K. , Groenen P. , van Krieken H. , Scheijen B.
Published: June 2019

Background:

Classic Hodgkin's lymphoma (cHL) has a high cure rate with current therapy, however relapse still occurs in 5%>10% of early stage and 15%>30% of advanced cHL. Interestingly, case reports and small series have shown that some of these relapses appear to be a new primary cHL. Assessment of clonal relationship between primary diagnosis and relapsed cHL samples after treatment will distinguish true relapse from second primary lymphoma. Clonality detection in cHL using conventional clonality assays has thus far been severely hampered by the low frequency of Hodgkin and Reed‐Sternberg (HRS) cells and limited DNA quality obtained from formalin‐fixed paraffin‐embedded (FFPE) material. Within the EuroClonality‐NGS Working Group, we have developed a novel approach to detect immunoglobulin (IG) heavy chain (IGH) and k light chain (IGK) gene rearrangements.

Aims:

The objective or our study is to determine the clonal relationship between HL diagnosis and relapse samples to assess the incidence of second primary malignancies in HL recurrences.

Methods:

We have collected 70 paired primary and relapse cHL cases. In 38/70 cases relapse occurred within three years after diagnosis, in 32/70 cases relapse occurred later than three years after diagnosis. EuroClonality‐NGS gene‐specific IGH‐VJ‐FR3, IGH‐DJ, IGK‐VJ and Intron‐Kde primer sets for small amplicon sizes were used to perform next‐generation sequencing (NGS)‐based clonality analysis with Ion Torrent PGM. Bioinformatic analyses with the interactive web‐based immunoprofiler ARResT/Interrogate allowed run/sample quality control followed by accurate identification of clonotypes.

Results:

We show that NGS‐based clonality assessment is highly suitable for detecting IG rearrangements in FFPE tissue specimens, including HL tissue specimens. Our preliminary data analysis of 7 paired diagnosis and relapse samples demonstrates the presence of identical clonotypes in 2 cases, while distinct clonotypes were observed in 3 other cases suggesting a new primary lymphoma. In the remaining 2 cases no specific clonotype could be identified in either diagnosis and/or relapse. The analysis of additional cHL recurrences by NGS‐based clonality assessment will reveal the true incidence of clonally unrelated lymphoma in relapsed cHL.

Summary/Conclusion:

This study is an important step towards establishment of NGS‐based clonality assessment in clinical practice for cHL, and eventually the improvement of therapeutic management of second primary cHL.
PF545 EASIX FOR PREDICTION OF SURVIVAL IN LOWER RISK MYELODYSPLASTIC SYNDROMES
Authors: Merz A.M. A. , Germing U. , Kobbe G. , Jauch A. , Radujkovic A. , Hummel M. , Benner A. , Merz M. , Müller‐Tidow C. , Dreger P. , Luft T.
Published: June 2019

Background:

Patients with myelodysplastic syndromes (MDS) are at risk of early death from cardiovascular complications due to the link between clonal hematopoiesis and endothelial dysfunction. EASIX (Endothelial Activation and Stress Index) is a novel marker of endothelial dysfunction that is calculated from serum creatinine, lactate dehydrogenase levels, and thrombocyte counts. EASIX has been established to predict endothelial complications after allogeneic transplantation.

Aims:

To analyze the impact of EASIX on the survival of patients with lower risk MDS and correlation with markers of endothelial activation.

Methods:

We investigated the impact of EASIX measured at first diagnosis on survival of lower risk MDS patients who received supportive treatment in two independent institutions: n = 100 (cohort I) and n = 338 (cohort II). Serum Angiopoietin‐2, suppressor of tumorigenicity (ST)‐2, soluble thrombomodulin (sCD141), interleukin (IL)‐18, IL37, S100A9, and HMGB1 were measured as markers of endothelial cell distress and inflammasomal activity and correlated to EASIX.

Results:

Univariate analysis showed that high EASIX was associated with shorter survival in both cohorts (Cohort I: hazard ratio (HR) per log2 increase: 1.50; 95% confidence interval (CI) 1.27–1.79; p‐value < 0.001 / Cohort II: HR 1.31 [1.20–1.42]; p‐value < 0.001). We visualized this continuous effect of EASIX by grouping patients into quartiles according to EASIX (Figure 1 A and B). Multivariate Cox regression analysis confirmed that EASIX remains a significant predictor of survival even after adjustment for age, sex, cytogenetic abnormalities and bone marrow blast counts (Cohort I: HR 1.35 [1.12–1.63]; p‐value = 0.002 / Cohort II HR 1.18 [1.08–1.29]; p‐value <0.001]. Models including EASIX showed lower prediction errors over time. Serum levels of Angiopoietin‐2 correlated significantly with EASIX (Spearman's rank correlation = 0.455, 95%CI 0.264–0.616, n = 74). Due to the lack of correlation between EASIX and S100A9 or IL‐1b, we performed a pathway analysis including serum HMGB1 and IL37. We observed a strong intra‐pathway correlation of S100A9 with IL1b, IL18, IL37, and HMGB1, arguing for the validity of our serum analyses

Summary/Conclusion:

We introduce EASIX as an easily accessible predictor for survival in patients with low‐risk MDS in best supportive care.

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PF574 TARGETED ULTRA‐DEEP NGS ASSESSMENT OF TP53 MUTATIONS IN MULTIPLE MYELOMA FROM WHOLE BONE MARROW
Authors: Petrackova A. , Sedlarikova L. , Minarik J. , Vasinek M. , Dyskova T. , Urbankova H. , Bacovsky J. , Papajik T. , Kriegova E.
Published: June 2019

Background:

Among the most important prognostic genetic aberrations in multiple myeloma (MM) are del(17p) and/or TP53 mutations. The use of the whole bone marrow (BM), when sorted MM cells are not available, may greatly simplify the NGS assessment in MM patients for clinical decisions.

Aims:

Therefore, the objective of our study was to assess applicability of ultra‐deep targeted NGS for analysis of TP53 mutations and other commonly mutated genes NRAS, KRAS and BRAF using the whole BM samples and compare it to results from MM sorted cells.

Methods:

BM samples were obtained from MM patients (n = 35, 12 M/23 F). The gDNA was isolated from whole BM (infiltration of plasma cells: median 16.4%, min‐max 1.2 ‐ 65.6%) and paired sorted MM cells. The full coding sequence and 5́and 3́UTR regions of the TP53 gene and hotspots of NRAS, KRAS and BRAF were analysed using ultra‐deep NGS with the MiSeq system (Illumina). The cut‐off for mutation detection was 1% variant allele frequency (VAF), the binomial distribution equation was used to determine a minimum number of mutant alleles.

Results:

Of MM patients, 22.9% (8/35) harboured mutations in TP53 gene, 20.0% (7/35) KRAS, 14.3% (5/35) NRAS and 8.6% (3/35) BRAF in the whole BM. In all patients, the VAF was in accordance with plasma cells infiltration in BM. Regarding TP53, five patients carried only TP53 mutations, two had a co‐occurrence of TP53 mutations and del(17p) and one had TP53 mutation together with 17chr trisomy as assessed by FISH. In TP53, all of the mutations except one case were observed with low frequency (VAF 2–9%). In cases when paired sorted sample was available, the mutations found in the whole BM were confirmed in sorted MM cells.

Summary/Conclusion:

Our results demonstrate the applicability of ultra‐deep targeted NGS in assessment of TP53 mutations in the whole BM samples in MM when sorted population is not available. Moreover, our data highlights the importance of assessment of TP53 mutations in MM patients, as they may occur regardless of del(17p). Our approach may simplify the assessment of mutational landscape in MM patients and thus impacts clinical decision making.

Grant support: MZ ČR VES16–32339A, IGA UP_2019_014, MH CZ–DRO (FNOL, 00098892), NV18–03‐00500
PF598 STEM CELL YIELD AND TRANSPLANTATION IN TRANSPLANT‐ELIGIBLE NEWLY DIAGNOSED MULTIPLE MYELOMA PATIENTS RECEIVING DARATUMUMAB + BORTEZOMIB/THALIDOMIDE/DEXAMETHASONE (D‐VTD): PHASE 3 CASSIOPEIA STUDY
Authors: Hulin C. , Moreau P. , Attal M. , Belhadj K. , Benboubker L. , Caillot D. , Facon T. , Garderet L. , Kuhnowski F. , Stoppa A.‐M. , Kolb B. , Tiab M. , Sonneveld P. , Jie K.‐S. , Westerman M. , Pei L. , Kampfenkel T. , de Boer C. , Vermeulen J. , van de Donk N.W.
Published: June 2019

Background:

High‐dose therapy (HDT) followed by autologous stem‐cell transplantation (ASCT) is the standard of care in transplant‐eligible newly diagnosed multiple myeloma (NDMM). In the phase 3 CASSIOPEIA study, daratumumab + standard‐of‐care regimen VTd (D‐VTd) significantly improved stringent complete response (sCR), complete response or better (≥CR), and minimal residual disease (MRD)‐negative rates and reduced the risk of progression or death versus VTd in NDMM patients who were eligible for transplant.

Aims:

Here, we assessed stem cell yield and transplantation results among patients receiving D‐VTd versus VTd induction prior to HDT and ASCT in Part 1 of the CASSIOPEIA trial.

Methods:

In Part 1, transplant‐eligible NDMM patients ages 18–65 years were randomized 1:1 to 4 pre‐transplant induction and 2 post‐transplant consolidation cycles of D‐VTd or VTd alone. After induction, patients underwent stem cell mobilization with cyclophosphamide 3 g/m2 (recommended dose) and granulocyte colony‐stimulating factor (G‐CSF). Peripheral blood stem cells were harvested based on response to mobilization. Plerixafor was administered if stem cell collection failed at first attempt and in accordance with institutional practice. Melphalan 200 mg/m2 IV was given as HDT prior to ASCT.

Results:

A total of 1,085 patients were randomized to D‐VTd (n = 543) or VTd (n = 542). Among patients who completed mobilization (D‐VTd, 506; VTd, 492), more patients in the D‐VTd arm received plerixafor during mobilization than in the VTd arm (21.7% vs 7.9%). Patients underwent a median (range) of 2 (1–6) versus 1 (1–4) days of apheresis for D‐VTd versus VTd. The median number of CD34+ cells collected was lower in patients receiving D‐VTd versus VTd (6.3 × 106/kg vs 8.9 × 106/kg). Nevertheless, a similar percentage of intention‐to‐treat patients receiving D‐VTd versus VTd underwent ASCT (90.1% vs 89.3%). The median number of CD34+ cells transplanted for D‐VTd versus VTd was 3.3 × 106/kg versus 4.3 × 106/kg. Hematopoietic reconstitution rates were high and similar in transplanted patients receiving D‐VTd versus VTd (99.8% vs 99.6%). For D‐VTd versus VTd, a median (range) of 13.0 (6–54) versus 13.0 (4–43) days was required to achieve sustained absolute neutrophil counts >500 cells/mm3, and a median (range) of 14.0 (2–56) versus 12.0 (1–47) days was required to achieve sustained platelets >20,000 cells/mm3 without transfusion.

Summary/Conclusion:

Stem cell mobilization and collection was feasible with D‐VTd induction. Adding daratumumab to VTd allowed successful transplantation in patients with NDMM who were transplant eligible.
PF654 EPIGENETIC ALTERATION OF CSK BINDING PROTEIN(CBP) IN MYELOPROLIFERATIVE NEOPLASMS COMPLEMENTS THE JAK2V617F MUTATION
Authors: Huang J. , Ye X.
Published: June 2019

Background:

Csk binding protein (CBP), a ubiquitously expressed transmembrane protein, functions as a suppressor of Src‐mediated tumor progression by promoting the inactivation of Src. CBP is widely reported to act as a scaffold in the Csk‐mediated negative regulationof Src family kinases (SFKs). First, CBP is phosphorylated by SFKs, then it associates withC‐terminal Src kinase (Csk) through a specific site (Tyr‐317 in humans) and brings it into proximity with membrane‐associated SFKs. After that, Csk phosphorylates the C‐terminal negative regulatory tyrosine residue of SFKs, which suppresses their activation. SFKs are membrane‐associated non‐receptor protein tyrosine kinases that play pivotal roles in regulating various cellular processes including proliferation, differentiation, adhesion, migration, and survival. Thus, CBP plays the opposite role in various Csk‐mediated cellular processes and might be a significant target for Csk‐mediated tumors.

Aims:

To explore the role of CBP in myeloproliferative neoplasms complements the JAK2V617F mutation.

Methods:

Bone marrow of 78 JAK2/V617F mutation positive MPN patients were collected, including 18 of 78 idiopathic myelofibrosis, 32 of 78 polycythaemia vera and 28 of 78 essential thrombocythaemia. The mononucleated cells separated, RNA extracted and the CBP expression level detected using real‐time quantitative PCR and MSP. SPSS 23.0 used for data analysis.

Results:

We identified CBP as a functional tumor suppressor gene frequently methylated in myeloproliferative neoplasms complements the JAK2V617F mutation. We further uncovered CBP as one of the up regulated genes in JAK2/V617F mutation positive cell lines after pharmacologic demethylation with 5 aza 2’ deoxycytidine (Aza). Methylation of CBP was detected in several JAK2/V617F mutation positive cells. Aberrant methylation was further detected in 60% of various types of JAK2/V617F mutation positive MPN, but not in any normal PBMC sample, and is thus tumor specific. The levels of CBP mRNA were significantly lower in hypermethylated samples than unmethylated samples, suggesting CBP may be epigenetically inactivated in MPN patients. Aza treatment led to CBP promoter demethylation and transcriptional reactivation in silenced cell lines, indicating a methylation mediated silencing. Meanwhile, phosphorylated JAK2 and STAT3 were progressively reduced.

Summary/Conclusion:

Our results indicate that epigenetic inactivation of CBP contributes to the constitutiveactivation of JAK2/STAT signaling. CBP methylation is a frequent event in myeloproliferative neoplasms complements the JAK2V617F mutation. Restoration of CBP expression by HMA may contribute to clinical treatment for MPN patients.
PF657 USE OF A NGS MYELOID PANEL TO FIND CLONALITY IN TRIPLE NEGATIVE ESSENTIAL THROMBOCYTHEMIA. IDENTIFICATION OF NEW MUTATIONS IN DRIVER GENES
Authors: Carreno‐Tarragona G. , López N. , Gutiérrez López de Ocariz X. , Rapado I. , Martínez‐López J. , Ayala R.
Published: June 2019

Background:

Essential Thrombocythemia is a clonal haematopoietic stem cell disorder characterized by hypercellularity of the bone marrow with effective haematopoietic maturation and increased numbers of platelets in the peripheral blood. Although more than 90% of the cases present typical mutations in JAK2, MPL and CALR, the remaining cases can become a diagnostic challenge as it requires the presence of a clonal marker or the absence of evidence for reactive thrombocytosis.

Aims:

To evaluate the use of a Myeloid Panel for the identification of clonal markers in TN ET cases and try to identify new mutations and prognostic determinants in these patients.

Methods:

A cohort of 32 ET negative for JAK2 V617F mutation (RT‐PCR), CALR canonic mutations (GENESCAN) and MPL W515K and W515L mutations (RT‐PCR) was selected. Average age at diagnosis was 49,08 (range 14–88). Male:Female ratio was 11:21. Average Haemoglobin, leukocytes and platelets at diagnosis were 14.14 g/dl 8,93 x109/L and 820x109/L, respectively. We performed targeted gene sequencing by NGS (Ion Torrent S5XL System–Thermofisher Scientific) using a panel of 33 (before March 2018) or 43 genes (after March 2018) implicated in leukemia prognosis.

Results:

With a median follow‐up of 5 years (range 0,02–25,43) 2 patients suffered transformation to acute myeloid leukemia, 1 progression to myelofibrosis and 1 presented with suffered a thrombotic event after diagnosis. We found clonality markers in 19 (59%) out of 32 patients. These presented an average of 1,84 (range 1–3) and 1,68 (range 1–3) mutations and mutated genes, respectively. 6 patients (31,57%) presented mutations in driver genes (JAK2, MPL and CALR). Three of them, family, presented with JAK2 R683G, a mutation previously described in acute lymphoblastic leukemia but not in myeloproliferative neoplasms. Other patient had JAK2 L393 V mutation, of undetermined significance and reported in population databases. Another presented the previously described MPL S505C and W515R mutations. Finally, we identified a new deletion in CALR exon 9 (c.1153_1155delAAG, p.K385del). 17 (89,47%) mutated patients presented mutations in non driver genes. Among those the most frequently mutated ones were TET2 (29%), ETV6 (17,6%), SF3B1 and KMT2A (both 11,7%). We found one mutation in VHL, DNMT3A, WT1, TP53, EPAS, CBL, IDH1, TPHO, KIT, ASXL1, EPOR and KRAS.

Summary/Conclusion:

Triple Negative TE suppose a diagnostic challenge. Here we show that targeted gene sequencing by a myeloid panel is able to identify clonality in up to 59% of the cases. Also, we have described new mutations in driver genes, gaining knowledge on TE molecular basis. Finally, larger cohorts of TN ETs are needed to clearly define the determinants and prognostic factors of this disease.
PF715 THE IMPACT OF CRIZANLIZUMAB ON VOC‐RELATED MEDICAL FACILITY VISITS
Authors: Bailey M. , Thompson M. , Brown S.
Published: June 2019

Background:

A major cause of morbidity among patients with sickle cell disease (SCD) is the intense, recurrent, unpredictable attacks, known as vaso‐occlusive crises (VOCs), which are responsible for >90% of hospital admissions in SCD. An important goal of pharmacological therapy is to prevent the occurrence of these painful episodes, and in turn, reduce the clinical and economic burden of the disease.

In December 2018, the United States Food and Drug Administration granted crizanlizumab (SEG101) Breakthrough Therapy designation for the prevention of VOCs in patients with SCD. This designation was granted based on positive results from the Phase II SUSTAIN trial, in which 5 mg/kg crizanlizumab was associated with a 45.3% reduction in the median annual rate of VOCs leading to healthcare visits compared with placebo.

Aims:

The aim of the current analysis was to investigate the impact of crizanlizumab on VOC‐related medical facility visits.

Methods:

sing data from the SUSTAIN trial, analyses were conducted to determine the cumulative number of VOC events across all patients, medical facility visits and by medical facility type in the 5 mg/kg crizanlizumab and placebo arms. The total cumulative number of patient days in the study was considered in determining the event rate per year, which was calculated as follows:

“[Total cumulative number of VOCs across all patients]/[Total number of days observed across all patients]” ∗ 365

Incidence rate ratios (IRR) were derived using a Poisson regression model. Maximum likelihood parameter estimates were generated with standard errors to produce confidence intervals and p‐values. Effect modification over time by group was assessed by maximum likelihood.

Results:

The analyses showed a reduction in the overall rate of VOC events requiring a medical facility visit in the 5 mg/kg crizanlizumab group compared with the placebo group. Further examination of the impact of crizanlizumab on specific sites of care demonstrated a reduction in visits to outpatient care sites, largely driven by reduced visits to emergency care units and SCD crisis centers (Table 1). A trend to reduced inpatient admissions was also observed.

Summary/Conclusion:

Payers aim to reimburse treatments for SCD that reduce both the clinical and economic burden of the disease. In the SUSTAIN trial, patients treated with 5 mg/kg crizanlizumab experienced a 45.3% reduction in the median annual rate of VOCs leading to healthcare visits compared with those receiving placebo. The current analysis demonstrates that this reduction in VOCs leading to a healthcare visit was seen in most medical facility visits, largely driven by reduced visits to emergency care units and specialized SCD crisis centers. These findings suggest that patients treated with crizanlizumab will experience a substantial reduction in health care resource utilization and associated costs.

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PF716 CLINICAL IMPACT OF PROGNOSTIC NUTRITIONAL INDEX IN DIFFUSE LARGE B CELL LYMPHOMA
Authors: Go S.‐I. , Lee G.‐W.
Published: June 2019

Please indicate where the abstract has been published before: Annals of Hematology

Background:

Cachexia is an indicator of tumor progression in patients with malignancy. Cachectic patients exhibit intolerance and a reduced response to antitumor therapy, and have an unfavorable prognosis. An international consensus proposed diagnostic criteria for cancer cachexia including weight loss, low body mass index (BMI), and/or presence of sarcopenia. Other potential biomarkers (e.g., albumin, C‐reactive protein, pro‐inflammatory cytokines, and microRNAs) and scoring systems (e.g., cachexia score [CASCO], Glasgow prognostic score [GPS], prognostic nutritional index [PNI]) have also been studied to diagnose cancer cachexia and assess its severity.

Aims:

In this study, we assessed the associations among PNI, other clinical outcomes, and survival in patients with DLBCL. Then we sought valid cachexia markers with prognostic significance and designed a novel model to improve the prognostic ability of well‐known clinical indices for patients with DLBCL.

Methods:

A total of 228 DLBCL patients treated with first‐line R‐CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) were retrospectively reviewed. PNI was calculated as 10 × serum levels of albumin (g/dL) + 0.005 × absolute lymphocyte count (/mm3). Patients were categorized into low‐ and high‐PNI groups based on a cut‐off value of 40. The nomogram for predicting overall survival (OS) was constructed using a Cox regression model. PNI was positively correlated with skeletal muscle index, body mass index, and serum levels of albumin.

Results:

The low‐PNI group had a lower complete response rate (60.3% vs. 87.6%), increased treatment‐related toxicity, and more frequent treatment discontinuation (43.5% vs. 8.8%) than the high‐PNI group. The median OS was shorter in the low‐PNI group than the high‐PNI group (15.6 months vs. not reached; p < 0.001, Figure.1). Multivariate Cox regression analyses showed that PNI, sarcopenia, and the international prognostic index (IPI) were independent prognostic factors for OS. The nomogram developed using this regression model showed excellent discriminatory ability for predicting OS (c‐index, 0.80) compared to the IPI alone (c‐index, 0.75).

Summary/Conclusion:

This study supports the results of a previous study [29], whereby low PNI is an independent poor prognostic factor in patients with DLBCL treated with first‐line R‐CHOP immunochemotherapy. In addition, we newly found that treatment‐related toxicity and early discontinuation of treatment occurred more frequently in DLBCL patients with low PNI. We anticipate that the new prognostic nomogram developed using PNI, SMI, and IPI may help to realize individualized therapy that considers both the disease characteristics and the patient's tolerance to treatment in patients with DLBCL. This will be validated externally in a future study.

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PF728 COMPARISON OF ALLOPURINOL AND FEBUXOSTAT FOR PREVENTION OF HYPERURICEMIA AND TUMOR LYSIS SYNDROME IN ACUTE LEUKEMIAS
Authors: Mirgh S.P. , Mahapatra M. , Seth T. , Dhawan R. , Aggarwal M. , Saxena R. , Pati H. , tyagi S.
Published: June 2019

Background:

Serum uric acid control is of prime importance in prevention of tumor lysis syndrome. Each mg/dl rise in uric acid increases the risk of tumor lysis syndrome and renal events by 1.75‐fold and 2.25‐fold respectively. We compared two xanthine oxidase inhibitors ‐ allopurinol and febuxostat as hypouricemic agents in patients of acute leukemias.

Aims:

The aims of the study were to assess the change in serum uric acid levels from baseline to day+7 after chemotherapy and to determine the incidence of tumor lysis syndrome in both groups.

Methods:

In this single‐institution prospective cohort study (study period – January2017 – July2018), acute leukemia patients scheduled to receive induction chemotherapy were administered either allopurinol or febuxostat, starting atleast 1 day prior to chemotherapy till 8 days after chemotherapy. Daily dose for Allopurinol was 300 mg/m2 and for febuxostat, it was 80 mg (10 mg daily for children < = 15years). Patients with baseline uric acid level >8 mg/dl, presence of hepatic or renal dysfunction and history of receiving rasburicase were excluded. The primary objective was to compare both the drugs in terms of decrease in serum uric acid levels analysed by area under curve (AUC) for a 7‐day treatment period.

Results:

A total of 120 patients (60 patients in each group) were recruited. Both groups were comparable in terms of gender, age, diagnosis and baseline uric acid levels. Mean AUC of serum uric acid day1–8 was 457.68 ± 27.55 mg‐h/dL versus 532.32 ± 34.39 mg‐h/dL, in favour of febuxostat [P = 0.09].The difference between the two study drugs was statistically significant for febuxostat on day+3 [P < 0.05] (Figure 1).10% (n = 6) patients on allopurinol developed TLS compared to 3.33% (n = 2) patients on febuxostat. The Odds ratio for tumor lysis syndrome in patients receiving febuxostat relative to those receiving allopurinol was 0.33. Drug related adverse events were 38.33% (n = 23) in allopurinol group, in contrast to 11.66% (n = 7) in the febuxostat group. Most common adverse event in allopurinol arm was gastrointestinal, whereas in febuxostat arm, it was asymptomatic transaminitis. Cutaneous reactions (6.6%;n = 4) were noticed only in allopurinol group.

Summary/Conclusion:

Irrespective of type of leukemia, lactate dehydrogenase levels, leukocyte counts and baseline uric acid levels, febuxostat in comparison to allopurinol, performed non‐inferior with respect to its uric acid lowering efficacy. It had relatively lesser risk of tumor lysis syndrome with a trend towards significance and a better safety profile.

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PF730 CHRONIC RENAL FAILURE IN CHILDHOOD CANCER: AN INSIGHT FROM KIDS INPATIENT DATABASE
Authors: Elsabbagh E.M. , Almasri M.
Published: June 2019

Background:

Chronic Renal Failure (CRF) is prevelant in oncology patients. CRF may pre‐exist cancer diagnosis, occur secondry to cancer infiltration, complicate chemotherapy and other toxic drugs or follow hematopoietic stem‐cell transplantation. CRF is associated with prolonged hospital stay, high healthcare cost and increased mortality. Despite the increased prevelance and these associations, the national rate and clinical outcome of CRF among pediatric oncology patients is not well described.

Aims:

Define CRF incidence and its health outcomes among pediatric oncology patients in the United States (U.S.).

Methods:

We performed a retrospective cohort analysis of the Health Cost and Utilization Project (HCUP) Kids’ Inpatient 2000–2012 Database (KID) for patient ≤ 20 years of age. Patients with principal diagnosis of acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic myeloid leukemia (CML), lymphomas (Hodgkin and non‐Hodgkin), brain tumor, neuroblastoma, bone tumors (Ewing's Sarcoma and Osteosarcoma) and hepatoblastoma were reviewed. Encounters for chemotherapy were excluded. Patients with medical diagnosis of CRF were identified using ICD‐9‐CM codes. We performed descriptive statistics to characterize the cohort in terms of demographic factors (age, race, sex, insurance type), hospital characteristics and comorbidities. Data weights were applied to sampled patients to provide national estimates. The in‐hospital mortality rate, total charges, and hospital length of stay (LOS) were compared between cancer patients with and without CRF using bivariable analyses.

Results:

A total of 266,113 admissions were included for analysis. The cohort was comprised of 1,035 patients with CRF, with an overall incidence 4 per 1,000 admissions. The median age was 15 years.51.5% of CKD patients were among the age group above 12‐year‐old. Males (57%), and whites (52.3%) were more commonly affected. South and Midwest regions (59.5%) of the U.S. had higher frequency of CRF. 15% of CRF complicated acute kidney injury (AKI). Lymphoma was the most common diagnosis associated with CRF (1.3%). Patients with CRF had significantly higher mortality rates (5.5% vs. 1.36%, p < 0.0001), longer median LOS (15 days vs. 4 days, p < 0.0001) in CRF patients complicated AKI and higher median total charges per hospitalization ($36,600 vs $18,856) when compared to patients without CRF.

Summary/Conclusion:

CRF in pediatric oncology patients is significantly associated with increased in‐hospital mortality and higher healthcare cost in pediatric oncology patients. Attention should be directed towards strategies to minimize risk of CRF in those population.
PF733 COMBINED ORAL ANALGESIA AND ANXIOLYSIS FOR PAIN ASSOCIATED WITH BONE MARROW ASPIRATION AND BIOPSY
Authors: Cerchione C. , Martinelli G. , Catalano L. , Pugliese N. , Pepa R. Della , Gravetti A. , Nappi D. , Pane F. , Martinelli V.
Published: June 2019

Background:

Bone marrow aspiration and biopsy (BMAB) is a painful procedure, and the commonly adopted local infiltration anesthesia (LIA) with lidocaine is unable to relieve the pain during the most uncomfortable phases, or the anticipatory anxiety related to pain recalling thereafter. As there are no formal guidelines for adding a sedoanalgesic premedication before beginning the BMAB, many combinations have been adopted by several authors.

Aims:

Our randomized and patient blinded trial aimed to evaluate, as primary end point, the efficacy and safety of opioid and benzodiazepine agent combination plus LIA in patients who underwent BMAB for hematological malignancies. Two secondary end points were: 1) to define if patients who already underwent to BMAB without LIA prefer sedoanalgesia; 2) to demonstrate if sedoanalgesia can influence the quality of the biological specimen harvested.

Methods:

Patients were randomly assigned into two arms for receiving either placebo plus LIA (standard group, 48,6%) or oral fentanyl citrate 200 mcg + oral midazolam 5 mg in addition to LIA (combo‐group, 51,4%) during BMAB. Pre‐procedural anxiety and procedural pain were assessed according to the Numered Rating Scale (NRS: 0–10), dividing the time of the procedure into five intervals (T0, T1, T2a, T2b, and T3) and evaluating discomfort grade during each moment of procedure in both groups. Cognitive function was measured before and 30 minutes after the procedure. Possible side effects were recorded, as well as the adequacy of tissue samples harvested. A total number 116 patients were enrolled in the study. 9 patients did not meet inclusion criteria and were excluded. 52 patients were randomized and assigned to standard group and 55 to combo group.

Results:

At T2b and T3 (corresponding to the biopsy time and time after the biopsy, respectively) there was a significantly lower (p <  0.05) perception of pain in the patients who received sedoanalgesia (combo‐group) compared to those who did not (standard group). Moreover, 100 % of the patients in combo group who had previously undergone this procedure without premedication reported that they would prefer sedoanalgesia for the subsequent procedures.

Summary/Conclusion:

Administration of oral analgesia and anxiolysis is a safe and feasible option to be used in outpatient setting; sedoanalgesia is very effective in reducing pain during the biopsy and it diminishes the anticipatory anxiety related to a painful procedure. Patients should have the possibility to choose between local anesthesia alone or sedoanalgesia plus local anesthesia.
PF758 MULTI‐CENTER, PHASE II STUDY ON HAPLOIDENTICAL BONE MARROW TRANSPLANTATION USING A RIC REGIMEN AND POST‐TRANSPLANT CYCLOPHOSPHAMIDE IN PATIENTS WITH POOR PROGNOSIS LYMPHOMAS
Authors: Castagna L. , Dodero A. , Patriarca F. , Onida F. , Olivieri A. , Russo D. , Majolino I. , Sarina B. , Mariotti J. , Bramanti S. , De Philippis C. , Tagliaferri E. , Carlo‐Stella C. , Fanin R. , Corradini P. , Santoro A.
Published: June 2019

Background:

Allogeneic stem cell transplantation from haploidentical donor using unmanipulated bone marrow and post‐transplantation cyclophosphamide (PT CY) has been largely used to cure high‐risk lymphomas. Using nonmyeloablative conditioning regimen, the relapse incidence is considered a concerning issue.

Aims:

The aim of our study was to prospectively evaluate the efficacy and the feasibility of thiotepa‐based RIC regimen in high risk lymphoma patients.

Methods:

We enrolled 49 patients, and of these 47 were evaluable. The conditioning regimen consisted of thiotepa 10 mg/kg in 2 days, fludarabine 90 mg/m2 in 3 days, CY 60 mg/kg in 2 days, and TBI 2 Gy or TMI‐TLI 2 Gy. Unmanipulated bone marrow stem cells from a haploidentical family donor was infused at day 0. Graft versus host disease (GVHD) prophylaxis consisted of cyclophosphamide 50 mg/kg/day on days 3 and 4, mycophenolate mofetil and cyclosporine from day 5. The primary end point was the 1‐year progression free survival (PFS).

Results:

Patient characteristics are reported in the Table. Median age was 43 years (19–68). 49% of patients was affected by HL and 51% was in CR. The median time to absolute neutrophil count (ANC) and platelet recovery were 22 days (14–44) and 27 (17–151), respectively. The cumulative incidence (CI) of ANC engraftment at 30 days and platelet count at 60 days were 89% (75–95) and 84% (66–92). 2 patients (DSA negative) had a primary graft failure. The cumulative incidence at 6‐month of grade 2–4 acute GVHD and 2‐year moderate‐severe chronic GVHD was 26% (14–39) and 23% (13–37), respectively. After a median follow‐up of 35 months (12–64), the 1‐year and 3‐year PFS were 67% (51–79) and 67% (51–79), respectively. The 1‐year and 3‐year OS were 77% (62–86) and 67% (51–79), the 3‐year relapse incidence was 26% (14–39), and the 1‐year NRM was 15% (7–27). The 1‐year GRFS was 58% (43–71). The cause of death in 7 patients was: bilateral not documented pneumonia, acute GVHD, transplant‐associated microangiopathy, graft failure, CNS hemorrhage and other toxicities (2).

Summary/Conclusion:

In a prospective multicenter study in poor risk lymphoma patients, a thiotepa‐based RIC was well tolerated with an encouraging 1‐year PFS. Both relapse incidence and NRM were acceptable. A comparison with similar patients conditioned with a nonmyeloablative conditioning regimen has been planned.

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PF762 EFFECTS OF TWO DOSES OF ANTITHYMOCYTE GLOBULIN IN CONDITIONING REGIMENS FOR HAPLOIDENTICAL PERIPHERAL BLOOD STEM CELL TRANSPLANTATION
Authors: wang M. , fang X. , jiang Y. , sui X. , li Y. , liu X. , wang X. , xu H. , wang X.
Published: June 2019

Background:

Antithymocyte globulin (ATG), an important in vivo T‐cell depletion strategy, has been used for graft‐versus‐host disease (GVHD) prophylaxis and shown significant clinical benefit. However, the optimal ATG dose remains unclear.

Aims:

To assess the effectiveness of ATG at a total dose of 10.0 mg/kg and 7.5 mg/kg for haploidentical peripheral blood stem cell transplantation (PBSCT).

Methods:

We retrospectively analyzed patients who underwent haploidentical PBSCT, receiving myeloablative conditioning and standard GVHD prophylaxis. ATG (rabbit thymoglobulin) at a total dose of 10.0 mg/kg (2.5 mg/kg on days −5 to −2) and 7.5 mg/kg (2.5 mg/kg on days −4 to −2) were used in the two groups.

Results:

40 and 35 patients were enrolled in the ATG‐10 and ATG‐7.5 groups, respectively. No significant difference was observed regarding the cumulative incidence of 100‐day grade II‐IV acute GVHD (20.0% vs 14.3%; p = 0.53) and 3‐year chronic GVHD (13.7% vs 15.7%; p = 0.83). The 3‐year probability of overall survival (OS) was 72.6% vs 74.4% (p = 0.81) and the 3‐year probability of GVHD‐free/relapse‐free survival (GRFS) was 69.0% vs 53.0% (p = 0.16). The incidence of relapse in the ATG‐7.5 group (30.9%) was higher compared with the ATG‐10.0 group (17.1%), but this difference was not statistically significant (p = 0.20). In multivariate analysis, the ATG dose was not associated with relapse, while no further respond to therapy (NR) before PBSCT predicted relapse (HR 1.19, p = 0.04). There were 5 patients (12.5%) and 8 patients (22.9%) in NR in the ATG‐10 and ATG‐7.5 groups, respectively (p = 0.19). Additionally, the ATG‐7.5 group had a trend for lower 300‐day incidence of EBV reactivation (92.5% vs 80.0%; p = 0.14) and CMV reactivation (90.5% vs 80.0%; p = 0.16), and lower 100‐day incidence of hemorrhagic cystitis (42.5% vs 28.6%; p = 0.15).

Summary/Conclusion:

7.5 mg/kg ATG led to lower incidence of EBV reactivation, CMV reactivation and hemorrhagic cystitis without compromising control of grade II‐IV acute GVHD, chronic GVHD and OS when compared with 10.0 mg/kg ATG. Therefore, ATG at a dose of 7.5 mg/kg could be considered for further study.
PF771 CHIMERISM MONITORING BY QPCR, A ROBUST PERFORMANCE FROM 0.05% TO 100%
Authors: Bouwmans E.E. , van Deutekom H.W. M. , Malestein R. , Luiken B. , Rozemuller E.H. , Penning M.T.
Published: June 2019

Background:

Investigating the chimeric status after stem cell transplantation is required for the detection of adverse transplant events. In comparison to STR analysis, qPCR allows for a quick and easy measurement with better sensitivity that can be as low as 0.05% for the recipient chimeric status. In comparison to STR analysis this is a substantial improvement.

Aims:

The presumption is that qPCR is most accurate in its detection of percentages below 20–30% and less accurate for higher percentages. Here however, we provide evidence that qPCR data can be trusted regardless the level of measured percentage.

Methods:

We have collected the data of 19 studies, spanning 6 years, from the UK NEQAS ‘Post‐Stem Cell Transplant Chimerism Monitoring’ trial. Each study consisted of four samples; one from the recipient, one from the donor and two samples with a chimeric status representing two time points after transplantation. The recipient and donor samples were genotyped applying the KMRtype workflow (GenDx) and the chimeric mixtures were then examined with all found informative assays applying the KMRtrack workflow (GenDx). Tests were performed on either a Viia7 or QuantStudio 6 qPCR system (Thermo Fisher).

Collected data was compared with the results reported by UK NEQAS, which are based on the results from all participating labs. From this comparison the standard deviation and relative error of the qPCR assay were calculated and plotted in an overview.

Results:

The chimerism percentages obtained covered a full range of chimeric status from 0 to 100%. When comparing the qPCR data with the data provided by UK NEQAS it indeed shows a higher absolute deviation with higher percentages in the qPCR data. However, in the qPCR data the relative error is the same throughout the whole range of chimeric status.

Summary/Conclusion:

From these results we can conclude that the qPCR technique is able to accurately detect genetic material in a chimeric mixture, not only in the lower levels but confidently from 0.05% to 100%.
PF796 THE EFFECT OF ANTI‐BETA2‐GLYCOPROTEIN I ANTIBODY UPON THROMBIN GENERATION IN NORMAL, LEIDEN HETEROZYGOUS AND FACTOR DEFICIENT PLASMAS
Authors: Szabó G. , Tarr T. , Soltész P. , Kappelmayer J.
Published: June 2019

Background:

The antiphospholipid syndrome (APS) is an acquired hypercoagulable condition, in which venous or arterial thromboses are caused by the presence of antiphospholipid antibodies (aPL). Anti‐β2glycoprotein I (anti‐β2GPI), highly correlating with the clinical manifestation of the syndrome, is the most significant aPL. Much evidence has uncovered insights into its molecular mechanisms, the exact molecular or cellular events are still not delineated.

Aims:

Our aim was to examine the effect of anti‐β2GPI antibodies from APS patients on pooled normal plasma (NP), Leiden heterozygous plasma (LP) and factor deficient plasmas (DP).

Methods:

Serum samples were collected form triple positive (anti‐β2GPI, anticardiolipin, lupus anticoagulant) APS patients with thrombosis in their history. Anti‐β2GPI IgG was purified in a two‐step affinity chromatography by Protein G and β2GPI affinity columns. Purified anti‐β2GPI IgG was added to NP, LP, or DP in thrombin generation test (TGT) up to 125 U/mL concentration in the presence of 1 pM tissue factor and 4 μM phospholipid.

Results:

In TGT, time (Lag Time) and quantity parameters (Peak and Endogenous Thrombin Potential [ETP]) were assessed. Having lupus anticoagulant effect, anti‐β2GPI showed significant prolongation in Lag Time in pooled NP (n = 9) by 24% (p < 0.001). Despite the fact that anti‐β2GPI delayed thrombin generation in time, it significantly increased ETP by 11% (p < 0.001). We assessed thrombin generation in LP samples without antibodies. Thrombin generation in LP began at the same time as that of the NP, there was no difference in Lag Time, but surprisingly Peak and ETP values were significantly lower than in NP (ETPNP: 1467 nM∗min, ETPLP: 920 nM∗min, p < 0.001), less thrombin was generated in LP. Anti‐β2GPI was able to exert similar effects on LP as in NP. Lag Time was delayed by 36% (p < 0.001), there was a non‐significant increase in ETP, but the Peak thrombin value was elevated by 32% (p < 0.05, n = 6). The effect of anti‐β2GPI was investigated on FVII, FIX, FXI and FXII deficient plasmas. Similar tendency was seen in intrinsic factor deficient plasmas, Lag Time was prolonged, Peak and ETP was elevated, but anti‐β2GPI could not exert significant effect on any of the deficient plasmas. However, the lack of FVII completely prevented the effect of anti‐β2GPI on thrombin generation.

Summary/Conclusion:

Anti‐β2GPI delayed thrombin generation in time, while it enhanced the amount of thrombin generated, which may in part explain the lupus anticoagulant paradox. In plasma from Leiden heterozygous patients, thrombin generation was also enhanced by anti‐β2GPI. In intrinsic factor (FIX, FXI, FXII) deficient plasmas, similar tendency was seen as in normal or Leiden plasmas, which was non‐significant, but FVII seems a crucial mediator in the prothrombotic effect of anti‐β2GPI antibodies.