scholarly journals Donor Chip Causes Donor-Derived Clonal Hematopoiesis As an Early Complication of Allogeneic Stem Cell Transplantation

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 987-987
Author(s):  
Christopher J. Gibson ◽  
James A. Kennedy ◽  
Sarah Nikiforow ◽  
John E. Dick ◽  
Jerome Ritz ◽  
...  
Keyword(s):  
Stem Cell ◽  
Board Of Directors ◽  
Hematologic Malignancy ◽  
Clonal Evolution ◽  
Donor Cell ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Clonal Hematopoiesis ◽  
Increased Risk ◽  
Rbc Indices

Background Allogeneic stem cell transplantation (HSCT) involves the transfer of healthy donor hematopoietic cells, including hematopoietic stem cells (HSCs) and mature immune effector cells, to recipients with high-risk hematologic malignancies. The success of HSCT is fundamentally dependent on engraftment of normal donor-derived hematopoiesis. Rarely, donor-derived cells undergo transformation to myeloid leukemia as a late complication of HSCT (donor cell leukemia, DCL), a process linked in some cases to pre-existing mutations in donor hematopoietic stem cells (HSCs). In healthy older adults, HSC mutations can cause clonal hematopoiesis of indeterminate potential (CHIP), which is associated with increased risk of hematologic malignancy and an increased risk of all-cause mortality. Among donors over age 40, the frequency of donor CHIP can be estimated to be 5 to 20-fold higher than the frequency of donor cell leukemia, suggesting that non-leukemic endpoints of donor derived clonality may be more prevalent and consequential than previously recognized. Methods We performed targeted next generation sequencing in patients who developed peripheral cytopenias or myeloid neoplasms in the context of 100% donor cell chimerism after allogeneic HSCT. We also prospectively sequenced potential donors who had abnormal CBC parameters, including WBC differential and RBC indices. To determine whether the mutations detected in recipients were of donor derivation, and to assess clonal evolution over time, we performed ultra-deep genotyping at 30,000-100,000X or droplet digital PCR (ddPCR) in the donor stem cell product and serial post-SCT samples. Results We identified four allogeneic SCT recipients with 100% chimerism who met inclusion criteria, two with late-onset hematologic malignancy (latency 23 and 10 years) and two with progressive cytopenias but no evidence of hematologic malignancy on bone marrow examination (latency 18 and 13 months). In each of these patients, sequencing of bone marrow or peripheral blood specimens revealed at least one somatic mutation (SF3B1 K666Q; U2AF1 S34F; DNMT3A T868N; DNMT3A Q356X) that could be used to assess the possibility of donor derivation. In all patients, we identified at least one mutation present in both the diagnostic post-HSCT recipient sample and the pre-HSCT banked donor stem cell product. Figure 1 shows post-HSCT clonal evolution from one case. In another case, we evaluated contemporaneous samples from the donor and recipient obtained at the time of diagnosis of DCL in the recipient (23 years after HSCT). We identified two key findings: 1) a shared SF3B1 K666 mutation in donor and recipient, and 2) divergent clonal evolution, with ASXL1 C789X in the donor, and ASXL1 G642fs, SETBP1 D868N, and SUZ12 D605E in the recipient (Figure 2). In this context, the recipient had a morphologic diagnosis of MDS/MPN overlap, while the donor had abnormal RBC indices but no cytopenias. Since CHIP is associated with subtle abnormalities in hematologic parameters even in the absence of overt cytopenias, we evaluated potential donors with non-exclusionary CBC abnormalities, such as abnormal white blood cell differential or elevated MCV. In two cases, we prospectively identified DNMT3A mutations (R736Cand R882H, variant allele fractions 11.5% and 2%, respectively), consistent with donor CHIP. In one case, the donor with CHIP was used for transplantation. At 90 days after HSCT, donor cell chimerism was 99%; sequencing of recipient peripheral blood revealed the donor-derived DNMT3A mutation and the recipient remained persistently anemic, macrocytic, and thrombocytopenic. Conclusion We identified healthy stem cell donors with clonal hematopoiesis, marked by mutations in canonical genetic drivers of myeloid malignancies. In each instance, the aberrant clone engrafted in the transplant recipient, underwent selective expansion, and caused development of abnormal hematopoietic function. Our findings suggest that donor-derived clonal hematopoiesis may be common, especially in grafts from older donors, and that donor CHIP may confer an unrecognized and increased risk of leukemic and non-leukemic endpoints. We further demonstrate that donor CHIP can be identified prospectively, thus highlighting an emerging challenge in HSCT that may influence donor selection strategies as the clinical significance of donor CHIP is systematically elucidated. Disclosures Ritz: Kiadis: Membership on an entity's Board of Directors or advisory committees. Soiffer:Juno: Membership on an entity's Board of Directors or advisory committees; Kiadis: Membership on an entity's Board of Directors or advisory committees; Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees. Lindsley:MedImmune: Research Funding; Takeda Pharmaceuticals: Consultancy.

scholarly journals Clonal Hematopoiesis and COVID-19 Severity in Cancer Patients

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 37-38
Author(s):  
Kelly L. Bolton ◽  
Michael Foote ◽  
Justin Jee ◽  
Anton Safonov ◽  
Ryan Ptashkin ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Cancer Patients ◽  
Research Funding ◽  
Cox Regression ◽  
Study Cohort ◽  
Private Company ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Clonal Hematopoiesis ◽  
Increased Risk

Background: Advanced age, medical co-morbidities and a pro-inflammatory immunologic profile are associated with severe COVID-19. Acquired somatic mutations in hematopoietic stem cells (clonal hematopoiesis or CH) are common in elderly individuals. Previous studies have shown CH is associated with alterations in immunologic repertoire and function. Here, we investigate whether CH predisposes to severe COVID-19 or other infections. Methods: We performed a retrospective cohort study of 39,291 adult cancer patients with non-hematologic malignancies who had their tumor and blood sequenced using a panel of 468 known cancer driver genes. We identified individuals who tested positive for SARS-CoV-2 between March 8, 2020 and June 9, 2020. We determined the association between CH and severe COVID-19 (hypoxic event, hospitalization or death) using multivariable logistic regression models. We used an established aggregation schema for ICD-CM codes to identify distinct infection subtypes. The relationship between CH and risk of incident infections was determined using multivariable Cox regression. Results: In the study cohort, 436 patients were positive for SARS-CoV-2 and 165 developed severe COVID-19. COVID-19 patients with CH were more likely to develop severe disease compared to non-severe (OR=1.8; 95% CI: 1.1-2.9; p=0.01). CH was also more common among patients with severe COVID-19 compared to COVID-19 negative individuals (OR=1.6, 95% CI: 1.2-2.4, p=0.01). In 62,891 person-years of follow-up, 4,059 individuals developed an infection. CH was associated with risk of sepsis (HR=1.13; 95% CI 1.01-1.25, p=0.04) and bacterial enteritis (HR=1.8, 95% CI 1.1-2.8, p=0.01). Conclusions: CH is associated with severe COVID-19 and an increased risk of other infections in cancer patients. Disclosures Bolton: GRAIL: Research Funding. Jee:MDSeq Inc.: Patents & Royalties. Papaemmanuil:Celgene: Consultancy, Honoraria, Research Funding; Prime Oncology: Consultancy, Honoraria; Illumina: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; MSKCC: Patents & Royalties; Kyowa Hakko Kirin: Consultancy, Honoraria; Isabl: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees. Berger:Illumina: Research Funding; Grail: Research Funding; Roche: Consultancy. Levine:Prelude Therapeutics: Research Funding; Qiagen: Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; Loxo: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; Imago: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; C4 Therapeutics: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; Isoplexis: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria, Research Funding; Lilly: Consultancy, Honoraria; Janssen: Consultancy; Astellas: Consultancy; Morphosys: Consultancy; Novartis: Consultancy; Amgen: Honoraria; Gilead: Honoraria. Zehir:Illumina: Honoraria; Memorial Sloan Kettering Cancer Center: Current Employment.

scholarly journals Lower Hematopoietic Progenitor Cell Counts and Yields at Subsequent Donations Is Influenced By a Shorter Inter-Donation Interval between the First and Subsequent Mobilizations

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1962-1962
Author(s):  
Sandhya R. Panch ◽  
Brent R. Logan ◽  
Jennifer A. Sees ◽  
Bipin N. Savani ◽  
Nirali N. Shah ◽  
...  
Keyword(s):  
Stem Cell ◽  
Board Of Directors ◽  
Peripheral Blood ◽  
Research Funding ◽  
Time Interval ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Peripheral Blood Cd34 ◽  
Cell Counts ◽  
Cd34 Cells

Introduction: Approximately 7% of unrelated hematopoietic stem cell (HSC) donors are asked to donate a subsequent time to the same or different recipient. In a recent large CIBMTR study of second time donors, Stroncek et al. incidentally found that second peripheral blood stem cell (PBSC) collections had lower total CD34+ cells, CD34+ cells per liter of whole blood processed, and CD34+ cells per kg donor weight. Based on smaller studies, the time between the two independent PBSC donations (inter-donation interval) as well as donor sex, race and baseline lymphocyte counts appear to influence CD34+ cell yields at subsequent donations. Our objective was to retrospectively evaluate factors contributory to CD34+ cell yields at subsequent PBSC donation amongst NMDP donors. Methods. The study population consisted of filgrastim (G-CSF) mobilized PBSC donors through the NMDP/CIBMTR between 2006 and 2017, with a subsequent donation of the same product. evaluated the impact of inter-donation interval, donor demographics (age, BMI, race, sex, G-CSF dose, year of procedure, need for central line) and changes in complete blood counts (CBC), on the CD34+ cell yields/liter (x106/L) of blood processed at second donation and pre-apheresis (Day 5) peripheral blood CD34+ cell counts/liter (x106/L) at second donation. Linear regression was used to model log cell yields as a function of donor and collection related variables, time between donations, and changes in baseline values from first to second donation. Stepwise model building, along with interactions among significant variables were assessed. The Pearson chi-square test or the Kruskal-Wallis test compared discrete variables or continuous variables, respectively. For multivariate analysis, a significance level of 0.01 was used due to the large number of variables considered. Results: Among 513 PBSC donors who subsequently donated a second PBSC product, clinically relevant decreases in values at the second donation were observed in pre-apheresis CD34+ cells (73.9 vs. 68.6; p=0.03), CD34+cells/L blood processed (32.2 vs. 30.1; p=0.06), and total final CD34+ cell count (x106) (608 vs. 556; p=0.02). Median time interval between first and second PBSC donations was 11.7 months (range: 0.3-128.1). Using the median pre-apheresis peripheral blood CD34+ cell counts from donation 1 as the cut-off for high versus low mobilizers, we found that individuals who were likely to be high or low mobilizers at first donation were also likely to be high or low mobilizers at second donation, respectively (Table 1). This was independent of the inter-donation interval. In multivariate analyses, those with an inter-donation interval of >12 months, demonstrated higher CD34+cells/L blood processed compared to donors donating within a year (mean ratio 1.15, p<0.0001). Change in donor BMI was also a predictor for PBSC yields. If donor BMI decreased at second donation, so did the CD34+cells/L blood processed (0.74, p <0.0001). An average G-CSF dose above 960mcg was also associated with an increase in CD34+cells/L blood processed compared to donors who received less than 960mcg (1.04, p=0.005). (Table 2A). Pre-apheresis peripheral blood CD34+ cells on Day 5 of second donation were also affected by the inter-donation interval, with higher cell counts associated with a longer time interval (>12 months) between donations (1.23, p<0.0001). Further, independent of the inter-donation interval, GCSF doses greater than 960mcg per day associated with higher pre-apheresis CD34+ cells at second donation (1.26, p<0.0001); as was a higher baseline WBC count (>6.9) (1.3, p<0.0001) (Table 2B). Conclusions: In this large retrospective study of second time unrelated PBSC donors, a longer inter-donation interval was confirmed to be associated with better PBSC mobilization and collection. Given hematopoietic stem cell cycling times of 9-12 months in humans, where possible, repeat donors may be chosen based on these intervals to optimize PBSC yields. Changes in BMI are also to be considered while recruiting repeat donors. Some of these parameters may be improved marginally by increasing G-CSF dose within permissible limits. In most instances, however, sub-optimal mobilizers at first donation appear to donate suboptimal numbers of HSC at their subsequent donation. Disclosures Pulsipher: CSL Behring: Membership on an entity's Board of Directors or advisory committees; Miltenyi: Research Funding; Bellicum: Consultancy; Amgen: Other: Lecture; Jazz: Other: Education for employees; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Medac: Honoraria. Shaw:Therakos: Other: Speaker Engagement.

scholarly journals Inducible SBDS Deficiency Impairs Bone Marrow Niche Function to Engraft Donor Hematopoietic Stem Cell after Transplantation

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3199-3199
Author(s):  
Ji Zha ◽  
Lori Kunselman ◽  
Hongbo Michael Xie ◽  
Brian Ennis ◽  
Jian-Meng Fan ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Stem Cell ◽  
Mouse Model ◽  
Board Of Directors ◽  
Hematopoietic Stem Cell ◽  
Graft Failure ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Bm Niche ◽  
Deficient Mice

Hematopoietic stem cell (HSC) transplantation (HSCT) is required for curative therapy for patients with high-risk hematologic malignancies, and a number of non-malignant disorders including inherited bone marrow failure syndromes (iBMFS). Strategies to enhance bone marrow (BM) niche capacity to engraft donor HSC have the potential to improve HSCT outcome by decreasing graft failure rates and enabling reduction in conditioning intensity and regimen-associated complications. Several studies in animal models of iBMFS have demonstrated that BM niche dysfunction contributes to both the pathogenesis of iBMFS, as well as impaired graft function after HSCT. We hypothesize that such iBMFS mouse models are useful tools for discovering targetable niche elements critical for donor engraftment after HSCT. Here, we report the development of a novel mouse model of Shwachman-Diamond Syndrome (SDS) driven by conditional Sbds deletion, which demonstrates profound impairment of healthy donor hematopoietic engraftment after HSCT due to pathway-specific dysfunctional signaling within SBDS-deficient recipient niches. We first attempted to delete Sbds specifically in mature osteoblasts by crossing Sbdsfl/flmice with Col1a1Cre+mice. However, the Col1a1CreSbdsExc progenies are embryonic lethal at E12-E15 stage due to developmental musculoskeletal abnormalities. Alternatively, we generated an inducible SDS mouse model by crossing Sbdsfl/flmice with Mx1Cre+ mice, and inducing Sbds deletion in Mx1-inducible BM hematopoietic and osteolineage niche cells by polyinosinic-polycytidilic acid (pIpC) administration. Compared with Sbdsfl/flcontrols, Mx1CreSbdsExc mice develop significantly decreased platelet counts, an inverted peripheral blood myeloid/lymphoid cell ratio, and reduced long-term HSC within BM, consistent with stress hematopoiesis seen in BMF and myelodysplastic syndromes. To assess whether inducible SBDS deficiency impacts niche function to engraft donor HSC, we transplanted GFP+ wildtype donor BM into pIpC-treated Mx1CreSbdsExc mice and Sbdsfl/flcontrols after 1100 cGy of total body irradiation (TBI). Following transplantation, Mx1CreSbdsExc recipient mice exhibit significantly higher mortality than controls (Figure 1). The decreased survival was related to primary graft failure, as Mx1CreSbdsExc mice exhibit persistent BM aplasia after HSCT and decreased GFP+ reconstitution in competitive secondary transplantation assays. We next sought to identify the molecular and cellular defects within BM niche cells that contribute to the engraftment deficits in SBDS-deficient mice. We performed RNA-seq analysis on the BM stromal cells from irradiated Mx1CreSbdsExc mice versus controls, and the results revealed that SBDS deficiency in BM niche cells caused disrupted gene expression within osteoclast differentiation, FcγR-mediated phagocytosis, and VEGF signaling pathways. Multiplex ELISA assays showed that the BM niche of irradiated Mx1CreSbdsExc mice expresses lower levels of CXCL12, P-selectin and IGF-1, along with higher levels of G-CSF, CCL3, osteopontin and CCL9 than controls. Together, these results suggest that poor donor HSC engraftment in SBDS-deficient mice is likely caused by alterations in niche-mediated donor HSC homing/retention, bone metabolism, host monocyte survival, signaling within IGF-1 and VEGF pathways, and an increased inflammatory state within BM niches. Moreover, flow cytometry analysis showed that compared to controls, the BM niche of irradiated Mx1CreSbdsExc mice contained far fewer megakaryocytes, a hematopoietic cell component of BM niches that we previously demonstrated to be critical in promoting osteoblastic niche expansion and donor HSC engraftment. Taken together, our data demonstrated that SBDS deficiency in BM niches results in reduced capacity to engraft donor HSC. We have identified multiple molecular and cellular defects in the SBDS-deficient niche contributing to this phenotype. Such niche signaling pathway-specific deficits implicate these pathways as critical for donor engraftment during HSCT, and suggest their potential role as targets of therapeutic approaches to enhance donor engraftment and improve HSCT outcome in any condition for which HSCT is required for cure. Disclosures Olson: Merck: Membership on an entity's Board of Directors or advisory committees; Bluebird Bio: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Miltenyi: Honoraria.

scholarly journals Clonal hematopoiesis in donors and long-term survivors of related allogeneic hematopoietic stem cell transplantation

Blood ◽  
2020 ◽  
Vol 135 (18) ◽  
pp. 1548-1559 ◽  
Author(s):  
Steffen Boettcher ◽  
C. Matthias Wilk ◽  
Jochen Singer ◽  
Fabian Beier ◽  
Elodie Burcklen ◽  
...  
Keyword(s):  
Stem Cell ◽  
Hematopoietic Stem Cell Transplantation ◽  
Stem Cell Transplantation ◽  
Cell Transplantation ◽  
Hematopoietic Stem Cell ◽  
Hematopoietic Stem ◽  
Clonal Hematopoiesis ◽  
Increased Risk ◽  
Long Term Survivors

Abstract Clonal hematopoiesis (CH) is associated with age and an increased risk of myeloid malignancies, cardiovascular risk, and all-cause mortality. We tested for CH in a setting where hematopoietic stem cells (HSCs) of the same individual are exposed to different degrees of proliferative stress and environments, ie, in long-term survivors of allogeneic hematopoietic stem cell transplantation (allo-HSCT) and their respective related donors (n = 42 donor-recipient pairs). With a median follow-up time since allo-HSCT of 16 years (range, 10-32 years), we found a total of 35 mutations in 23 out of 84 (27.4%) study participants. Ten out of 42 donors (23.8%) and 13 out of 42 recipients (31%) had CH. CH was associated with older donor and recipient age. We identified 5 cases of donor-engrafted CH, with 1 case progressing into myelodysplastic syndrome in both donor and recipient. Four out of 5 cases showed increased clone size in recipients compared with donors. We further characterized the hematopoietic system in individuals with CH as follows: (1) CH was consistently present in myeloid cells but varied in penetrance in B and T cells; (2) colony-forming units (CFUs) revealed clonal evolution or multiple independent clones in individuals with multiple CH mutations; and (3) telomere shortening determined in granulocytes suggested ∼20 years of added proliferative history of HSCs in recipients compared with their donors, with telomere length in CH vs non-CH CFUs showing varying patterns. This study provides insight into the long-term behavior of the same human HSCs and respective CH development under different proliferative conditions.

Plerixafor (Mozobil ®)Plus G-CSF Is Effective in Mobilizing Hematopoietic Stem Cells in Patients with Concurrent Thrombocytopenia Undergoing Autologous Hematopoietic Stem Cell Transplantation.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3229-3229 ◽  
Author(s):  
Ivana N Micallef ◽  
Eric Jacobsen ◽  
Paul Shaughnessy ◽  
Sachin Marulkar ◽  
Purvi Mody ◽  
...  
Keyword(s):  
Stem Cell ◽  
Platelet Count ◽  
Board Of Directors ◽  
Research Funding ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Platelet Counts ◽  
Cd34 Cells ◽  
Low Platelet Count ◽  
Equity Ownership

Abstract Abstract 3229 Poster Board III-166 Introduction Low platelet count prior to mobilization is a significant predictive factor for mobilization failure in patients with non-Hodgkin's lymphoma (NHL) or Hodgkin's disease (HD) undergoing autologous hematopoietic stem cell (HSC) transplantation (auto-HSCT; Hosing C, et al, Am J Hematol. 2009). The purpose of this study is to assess the efficacy of HSC mobilization with plerixafor plus G-CSF in patients with concomitant thrombocytopenia undergoing auto-HSCT. Methods Patients who had failed successful HSC collection with any mobilization regimen were remobilized with plerixafor plus G-CSF as part of a compassionate use program (CUP). Mobilization failure was defined as the inability to collect 2 ×106 CD34+ cells/kg or inability to achieve a peripheral blood count of ≥10 CD34+ cells/μl without having undergone apheresis. As part of the CUP, G-CSF (10μg/kg) was administered subcutaneously (SC) every morning for 4 days. Plerixafor (0.24 mg/kg SC) was administered in the evening on Day 4, approximately 11 hours prior to the initiation of apheresis the following day. On Day 5, G-CSF was administered and apheresis was initiated. Plerixafor, G-CSF and apheresis were repeated daily until patients collected the minimum of 2 × 106 CD34+ cells/kg for auto-HSCT. Patients in the CUP with available data on pre-mobilization platelet counts were included in this analysis. While patients with a platelet count <85 × 109/L were excluded from the CUP, some patients received waivers and were included in this analysis. Efficacy of remobilization with plerixafor + G-CSF was evaluated in patients with platelet counts ≤ 100 × 109/L or ≤ 150 × 109/L. Results Of the 833 patients in the plerixafor CUP database, pre-mobilization platelet counts were available for 219 patients (NHL=115, MM=66, HD=20 and other=18.). Of these, 92 patients (NHL=49, MM=25, HD=8 and other=10) had pre-mobilization platelet counts ≤ 150 × 109/L; the median platelet count was 115 × 109/L (range, 50-150). The median age was 60 years (range 20-76) and 60.4% of the patients were male. Fifty-nine patients (64.1%) collected ≥2 × 109 CD34+ cells/kg and 13 patients (14.1%) achieved ≥5 × 106 CD34+ cells/kg. The median CD34+ cell yield was 2.56 × 106 CD34+ cells/kg. The proportion of patients proceeding to transplant was 68.5%. The median time to neutrophil and platelet engraftment was 12 days and 22 days, respectively. Similar results were obtained when efficacy of plerixafor + G-CSF was evaluated in 29 patients with platelet counts ≤ 100 × 109/L (NHL=12, MM=10, HD=3 and other=4). The median platelet count in these patients was 83 × 109/L (range, 50-100). The median age was 59 years (range 23-73) and 60.4% of the patients were male. The minimal and optimal cell dose was achieved in 19(65.5%) and 3(10.3%) patients, respectively. The median CD34+ cell yield was 2.92 × 106 CD34+ cells/kg. The proportion of patients proceeding to transplant was 62.1%. The median time to neutrophil and platelet engraftment was 12 days and 23 days, respectively. Conclusions For patients mobilized with G-CSF alone or chemotherapy ±G-CSF, a low platelet count prior to mobilization is a significant predictor of mobilization failure. These data demonstrate that in patients with thrombocytopenia who have failed prior mobilization attempts, remobilization with plerixafor plus G-CSF allows ∼65% of the patients to collect the minimal cell dose to proceed to transplantation. Thus, in patients predicted or proven to be poor mobilizers, addition of plerixafor may increase stem cell yields. Future studies should investigate the efficacy of plerixafor + G-CSF in front line mobilization in patients with low platelet counts prior to mobilization. Disclosures Micallef: Genzyme Corporation: Membership on an entity's Board of Directors or advisory committees, Research Funding. Jacobsen:Genzyme Corporation: Research Funding. Shaughnessy:Genzyme Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Marulkar:Genzyme Corporation: Employment, Equity Ownership. Mody:Genzyme Corporation: Employment, Equity Ownership. van Rhee:Genzyme Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

CML-CP Mouse Model of Genomic Instability.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1210-1210
Author(s):  
Elisabeth Bolton ◽  
Linda Kamp ◽  
Hardik Modi ◽  
Ravi Bhatia ◽  
Steffen Koschmieder ◽  
...  
Keyword(s):  
Stem Cells ◽  
Dna Damage ◽  
Stem Cell ◽  
Mouse Model ◽  
Board Of Directors ◽  
Genomic Instability ◽  
Oxidative Dna Damage ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Dependent Effect

Abstract Abstract 1210 Background: BCR-ABL1 transforms hematopoietic stem cells to induce chronic myeloid leukemia in chronic phase (CML-CP). Although CML is stem cell-derived, it is a progenitor cell-driven disease. In CML-CP, leukemia stem cells (LSCs) are characterized by elevated BCR-ABL1 expression in comparison to leukemia progenitor cells (LPCs). Increased expression of BCR-ABL1 kinase is also associated with progression from CML-CP to CML-blast phase. Previously we showed that BCR-ABL1 kinase stimulates reactive oxygen species (ROS)-dependent DNA damage resulting in genomic instability in vitro, which was responsible for acquired imatinib-resistance and accumulation of chromosomal aberrations (Nowicki et al., Blood, 2005; Koptyra et al., Blood, 2006; Koptyra et al., Leukemia, 2008). Result: To examine the effects of BCR-ABL1 expression on genomic instability during in vivo leukemogenesis we employed an inducible transgenic mouse model of CML-CP with targeted expression of p210BCR-ABL1 in hematopoietic stem and progenitor cells (Koschmieder et al., Blood, 2005). Mice exhibiting CML-CP-like disease resulting from BCR-ABL1 induction demonstrated splenomegaly, leukocytosis, and Gr1+/CD11b+ myeloid expansion in bone marrow, spleen and peripheral blood, as detected by FACS analysis. BCR-ABL1 mRNA expression was higher in Lin-c-Kit+Sca1+ stem-enriched cells than in Lin-c-Kit+Sca1- progenitor-enriched cells, thus reminiscent of CML-CP (LSCs>LPCs). BCR-ABL1 increased levels of ROS (hydrogen peroxide, hydroxyl radical) and oxidative DNA lesions (8-oxoG) in LSC-enriched Lin-c-Kit+Sca1+ cells. Preliminary data also suggested that quiescent (CFSEmax) Lin-c-Kit+Sca1+ cells from BCR-ABL1-induced mice exhibited greater ROS (superoxide) production than non-induced counter parts. Moreover, higher levels of ROS were detected in BCR-ABL1-positive Lin-c-Kit+Sca1+ stem-enriched population in comparison to BCR-ABL1-positive Lin-c-Kit+Sca1- progenitor population, suggesting a dosage-dependent effect of BCR-ABL1. To confirm that BCR-ABL1 exerts a dosage-dependent effect on ROS-induced oxidative DNA damage, we showed that the levels of ROS, 8-oxoG and DNA double-strand breaks were proportional to BCR-ABL1 kinase expression in murine 32Dc13 and human CD34+ cells. Conclusion: In summary, this mouse model recapitulates the BCR-ABL1 expression profile attributed to stem and progenitor populations in human CML-CP. It also shows that the BCR-ABL1-positive, stem cell-enriched Lin-c-Kit+Sca1+ population displays elevated levels of ROS and oxidative DNA damage in comparison to normal counterparts, which makes it suitable to study the mechanisms of genomic instability in LSCs. Single nucleotide polymorphism (SNP) arrays will shed more light on the genomic instability of this BCR-ABL1-induced transgenic model of CML-CP. Disclosures: Koschmieder: Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Membership on an entity's Board of Directors or advisory committees.

A Retrospective Study on Safety, Efficacy and Cost of the Chemo-Mobilization for Patients Planned to Undergo Autologous Hematopoietic Stem Cell Transplant: The Secom Study

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 5903-5903
Author(s):  
Surapol Issaragrilsil ◽  
Yeow-Tee YT Goh ◽  
Anskar Y.H. Leung ◽  
S Fadilah S Abdul Wahid ◽  
Hwai Tzeng Cheng
Keyword(s):  
Stem Cell ◽  
Febrile Neutropenia ◽  
Board Of Directors ◽  
High Dose Chemotherapy ◽  
High Dose ◽  
Asian Countries ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Grade 3 ◽  
The Cost

Abstract Introduction: Failure of hematopoietic stem cell (HSC) mobilization occurs in 5 to 30% patients planning for high dose chemotherapy and autologous HSC transplantation worldwide. It has adverse impact on patient outcomes and significantly increases health care burden. Data regarding HSC mobilization based on chemotherapy + granulocyte colony stimulating factor (G-CSF) in Asia are currently limited. Objective: The primary objective was to determine the safety and efficacy of HSC chemo-mobilization protocols in Asia for patients with non-Hodgkin lymphoma (NHL) or multiple myeloma (MM) planning for autologous HSCT. The secondary objective was to provide an estimate of the cost of chemo-mobilization in Asian countries Study Design: This was a multicenter, multinational retrospective observational study. Patients with NHL or MM undergoing chemo-mobilization for planned autologous HSCT between 1 Jan 2009 to 31 Dec 2012 in five Asian countries including Thailand, Singapore, Malaysia, Hong Kong and Taiwan, were retrospectively included in the study. Patient demographics, disease diagnoses, previous treatment history as well as complete blood counts prior to chemo-mobilization and apheresis, were collected. Results: A total of 526 patients (male/female = 207/219) were analyzed (diagnoses: NHL=257; MM=269). 160 patients were recruited from Thailand, 98 from Malaysia, 161 from Taiwan, 59 from Singapore and 48 from HK. Median age for the overall group was 53 years (range: 15-82). The most common mobilization regimen was cyclophosphamide + G-CSF; 235 (87.4%) in MM and 72 (28%) in NHL patients. 448 (85.2%) patients had reached at least HSC yield of 2 x 106CD 34+ cells/kg in 1 or 2 apheresis days. During chemo-mobilization, 108 (20.5%) patients were without negative clinical events (grade 3/4 neutropenia, febrile neutropenia, prolonged hospitalization, bone pain, fever, gastrointestinal, line infections or others). Grade 3/4 neutropenia and febrile neutropenia occurred in 401 (76.2%) and 72 (13.7%) patients, respectively. Median number of apheresis sessions was 2 (range: 1-5). Median cost of mobilization was 6,200USD (9,000-48,000). The respective median costs in USD (range) was; 3,500 (1,500-28,500) in Thailand, 6,900 (2,300-29,600) in Malaysia, 7,700 (3,400-48,000) in Taiwan and 9,200 (900-45,400) in Singapore. 436 (82.9%) patients proceeded to receive high dose chemotherapy and HSCT but 94 (17.87%) patients did not, due to insufficient HSC yield (n=26, 4.94 %), progression of disease (n=18, 3.42 %), patient not fit/ withdrawal from study (n=19, 3.61 %), patient expiry (n=11, 2.09 %) and other reasons (n=20, 3.80 %). Conclusion: Cyclophosphamide and G-CSF is the most common mobilization regimen used in Asian countries. Current chemo mobilization regimens are associated with a satisfactory rate of successful stem cell collection but with a high rate of significant toxicity. More than three-quarter of patients suffered from grade 3/4 toxicity during chemo-mobilization, however, only 20% of them had febrile neutropenia. Variations exist in the cost of chemo-mobilization in Asia, both among and within countries. Disclosures Goh: Novartis Pte Ltd: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Jannsen Pharmaceuticals Inc: Research Funding; Bristol-Myres Squibb: Membership on an entity's Board of Directors or advisory committees; Gilead Sciences: Honoraria, Membership on an entity's Board of Directors or advisory committees; Hospira Inc: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Mutational Studies Using Next Generation Sequencing in High Risk Myelodysplastic Syndromes and Secondary Acute Myeloid Leukemia Patients Treated with Azacitidine (High risk MDS 2009 protocol from CETLAM Group)

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2905-2905
Author(s):  
Marta Cabezon ◽  
Joan Bargay ◽  
Blanca Xicoy ◽  
Laura Palomo ◽  
Sílvia Marcé ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
High Risk ◽  
Treatment Response ◽  
Board Of Directors ◽  
Myelodysplastic Syndromes ◽  
Myeloid Leukemia ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Increased Risk ◽  
Acute Myeloid

Abstract INTRODUCTION: Myelodysplastic syndromes (MDS) are a group of myeloid neoplasms originated in hematopoietic stem cells, characterized by citopenias, dysplasia in one or more cell lines, ineffective hematopoiesis and an increased risk of progression to acute myeloid leukemia (AML). Treatment of MDS depends on subtype and prognostic category. DNA methyltranferase inhibitors are approved for high risk MDS. Over the past decade, the application of new high-throughput technologies to the study of MDS has led to the identification of several recurrently mutated genes. These include genes producing proteins involved in RNA splicing, DNA methylation, chromatin modification, transcription, DNA repair control, cohesin function, RAS pathway, and DNA replication. There is a significant overlap between the genes mutated commonly in MDS with those found in AML. Mutation status is not widely used to select treatment in MDS. The aim of this study is to define the mutational status of MDS and secondary AML (sAML) patients at diagnosis that have been treated with azacitidine (AZA) to see if it could help to discriminate which patients will respond from those who will not. MATERIAL AND METHODS: A prospective study was performed on 36 patients with MDS and sAML treated with AZA. Genomic DNA was obtained from bone marrow at diagnosis. SeqCap EZ and KAPA Library Preparation Kit (Roche) reagents have been used to enrich DNA of 83 genes implicated in myeloid neoplasm. The customized panel has been analyzed in MiSeq Illumina platform with 150bp paired-end reads. Samples were preliminary analyzed using Illumina MiSeq Reporter and Variant Studio softwares. Data from response to treatment and survival have been collected from all patients. RESULTS:The mean depth of the targeted resequencing per base was 685-fold. After filtering all the variations obtained for quality, biological consequence and discard the known SNPs, we have obtained 162 variations, including 145 single nucleotide variants (SNV) and 17 insertions/deletions. All patients harbored at least 1 alteration with a mean of 4.5 variants per sample. The average of alterations detected in each cytological category can be observed in Table 1.Table 1.Average abnormalities detected by cytological category.Nº patientsAverage of alterations detected for patient (range)sAML104,8 (1-8)RAEB-274,9 (2-8)RAEB-1123,7 (1-6)RCDM54,4 (3-7)RCDM-RS16RARs11The most frequent altered genes have been TP53, TET2 and DNMT3A. The numbers of variations detected for each gene are represented in Table 2.Complete results, including correlation with treatment response will be presented in the meeting.Table 2.Number of variations in each gene.GeneNº of variations foundNº of diferent variationsNº of patients with variationsFrequency of variationsTP5322191952,8%TET214101027,8%DNMT3A88822,2%CREBBP75719,4%SRSF271719,4%ASXL165616,7%U2AF162616,7%EP30053513,9%STAG255513,9%CUX144411,1%ETV643411,1%MLL (KMT2A)43411,1%RUNX14438,3%BCOR3338,3%CDH133338,3%CTNNA13238,3%EZH23338,3%GCAT3338,3%MLL2 (KMT2D)3338,3%NF13338,3%PDGFRB3338,3%SH2B33338,3%TGM23238,3%UMODL13338,3%CEBPA2125,6%CSF3R2225,6%GATA22125,6%PHLPP12225,6%RAD212225,6%SF3B12125,6%SUZ122225,6%TIMM502125,6%Others*1112,8%*ABL1, BCORL1, CALR, CDH3, IDH2, KRAS, LUC7L2, NPM1, NRAS, PHF6, SF3A1, SFPQ, SMC3, TERT, WT1, ZRSR2. CONCLUSIONS: Targeted deep-sequencing technique is a good tool to study mutational profile in MDS and sAML. SNV are the most frequent type of alteration found in our cohort. The patients with sAML and RAEB-2 present more variations than patients with RAEB-1. The rest of groups are less representing to be evaluated. The most affected genes match with those described in the literature, with some exceptions that need to be studied in more detail. We expect to predict in advance which patients are going to respond when we study the correlation of mutational analysis with treatment response. Acknowledgments: Instituto de Salud Carlos III, Ministerio de Sanidad y Consumo, Spain (PI 11/02519); 2014 SGR225 (GRE) Generalitat de Catalunya; Fundació Josep Carreras, Obra Social "La Caixa" and Celgene Spain. Diana Domínguez for her technical assistance Disclosures Valcarcel: Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Allogeneic Hematopoietic Stem Cell Transplant in Advanced Multiple Myeloma: Experience from a Single Center

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 5536-5536
Author(s):  
Yizel Elena Paz Nuñez ◽  
Beatriz Aguado Bueno ◽  
Isabel vicuña Andrés ◽  
Ángela Figuera Álvarez ◽  
Miriam González-Pardo ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Stem Cell ◽  
Board Of Directors ◽  
Hematopoietic Stem Cell ◽  
Hematopoietic Stem Cell Transplant ◽  
Stem Cell Transplant ◽  
Cell Transplant ◽  
Advisory Committees ◽  
Hematopoietic Stem

Abstract Introduction The prognosis of patients with multiple myeloma (MM) has improved in the last years due to the important advances in the knowledge of the biology of the disease, the implementation of new drugs and the incorporation of autologous hematopoietic stem cell transplant (autoHSCT). The allogenic hematopoietic stem cell transplant (alloHSCT) continues to be controversial: it offers a curative potential but with the cost of high toxicity, limiting the procedure to those young patients with a high-risk disease. This procedure shall be performed in expert centers and, whenever possible, in the context of a clinical trial. In the following we describe the experience of our center with alloHSCT in advance multiple myeloma patients. Patients and methods A total of 18 patients were diagnosed with multiple myeloma received an alloHSCT during a 13 year period (1996-2013), with a median age of 46 ± 5.9 years. All of our patients received an allogenic HLA matched sibling donor with reduced-intensity conditioning. The majority of patients were transplanted because of advanced disease, relapse after an autologous transplant or as part of a sequential transplant in patient with a high risk disease. One patient received, in two occasions, an alloHSCT. Around 70% of patients had received more than 3 previous lines of treatment including, in nearly 95%, an autoHSCT. Patient's characteristics can be found on table 1, characteristics of the procedure can be found in table 2.Table 1.Patient«s CharacteristicsN (%)GenderMale Female10 (55,5%) 9 (44,4%)Secreted ProteinIgGκ IgG λ IgA κ BJ Plasmocitoma8 (44,4%) 4 (22,2%) 2 (11,1%) 3 (16,7%) 1 (5,6%)Debut DS stageII-A II-B III-A III-B Plasmocitoma5 (27,8%) 1 (5,6%) 8 (44,4%) 3 (16,7%) 1 (5,6%)Cytogentics at diagnosisMissing Unfavorable Favorable10 (55,5%) 6 (33,3%) 2 (11,1%)Previous lines of treatment²2 3-4 ³56 (33,3%) 10 (55,5%) 2 (11,1%)Previous autoHSCTYes No17 (94,5%) 1 (5,6%)Previous radiotherapyYes No8 (44,4%) 10 (55,6%)Disease status at transplantComplete remission Partial remission Relapse9 (50,0%) 3 (16,7%) 6 (33,3%)Table 2.Treatment characteristicsN (%)Conditioning regimenMyeloablative Reduced-intensity6 (33,3%) 12 (66.7%)Stem cell sourceBone marrow Peripheral blood4 (22.2%) 14 (77.8%)GVHD prophylaxisCsA+MTXCsA+CSCsA+MMF10 (55.6%) 3 (16.7%) 5 (27.8%)InfectionsYes No16 (88.9%) 2 (11.1%)MucositisYes No12 (66.7%) 6 (33.3%)Acute GVHDYes II-IV III-IV No4 (22.3%) 3 (16.7%) 1 (5.6%) 14 (77.8%)Chronic GVHDNo Limited Extensive8 (44.3%) 5 (27.8%) 5 (27.8%) Results: Transplant related mortality (TRM) before day 100th was one case due to a thromboembolic event. Global TRM was 16.6% (3 cases). The incidence of acute graft versus host disease (aGVHD) was 22%, controlled on most cases when corticosteroids were initiated. More than half of the patients developed chronic graft versus host disease (cGVHD), with an equal distribution on either presentation as limited or extensive. (Table 2) The total number of patients eligible for analysis was 17 (one patient was lost on follow-up). With a median follow up of 11 years, the overall survival (OS) was of 8.06 years [IC 95% 4,33-11,78] (figure 1.) and the estimated progression free survival (PFS) was of 25.83 months [IC 95% 8.87-42.79](figure 2). A total of 5 (29,4%) patients are still alive and 2 (11,7%) of them are in complete remission, of these 1 patient did not have a previous autoHSCT with a follow up of almost 15 years. Conclusions: Our results are similar to those reflected on the literature1-2. However we have to point out that our population is homogenous with advanced MM with more than 3 previous lines of treatment including in most cases auto-HSCT. In spite of this, morbility and mortality in our cohort was acceptable with the limitation of a high rate of cGVHD. There is a need of more studies including more patients to evaluate the role of alloHSCT in the era of new drugs for MM. References 1. Rosi-ol L et al. Allogeneic hematopoietic SCT in multiple myeloma: long-term results from a single institution. Bone Marrow Transplant. 2015. 2. Beaussant Y et al. Hematopoietic Stem Cell Transplantation in Multiple Myeloma: A Retrospective Study of the Société Française de Greffe de Moelle et de Thérapie Cellulaire (SFGM-TC). Biol Blood Marrow Transplant. 2015 Disclosures Alegre: Celgene Corporation: 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.

The Abundance of Certain Bacteria in the Intestinal Flora Is Associated with Relapse after Allogeneic Hematopoietic Stem Cell Transplantation

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 744-744 ◽  
Author(s):  
Jonathan Peled ◽  
Eric R. Littman ◽  
Lilan Ling ◽  
Satyajit Kosuri ◽  
Molly Maloy ◽  
...  
Keyword(s):  
Overall Survival ◽  
Stem Cell ◽  
Board Of Directors ◽  
Research Funding ◽  
Intestinal Flora ◽  
Advisory Board ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Streptococcus Anginosus ◽  
Conditioning Intensity

Abstract The major causes of mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT) are relapse, graft-versus-host disease (GVHD), and infection. We have previously reported that changes in the intestinal flora can affect GVHD, bacteremia, and overall survival. As intestinal bacteria are potent modulators of systemic immune responses, and since GVHD is correlated with graft-versus-tumor activity, we hypothesized that components of the intestinal flora could be associated with relapse after allo-HSCT. We applied a biomarker-discovery approach and performed a retrospective observational analysis of 160 adults who received an unmodified (T-cell-replete) allograft. Patients were prospectively enrolled in a fecal biospecimen-collection protocol. For this analysis, we selected patients who had at least one specimen during the first 3 weeks following allo-HSCT. The primary diseases in this cohort were AML (37%), Non-Hodgkin's Lymphoma (33%), ALL (8%), MDS (7%), CLL (6%), Hodgkin's Lymphoma (6%), CML (2%), and myeloproliferative neoplasm (2%). The mean age of the patients was 52 years (range 21-75). They were conditioned with ablative (17%), reduced-intensity (64%), and nonmyeloablative (19%) regimens. They received grafts from cord blood (46%), unrelated adults (33%), or related adults (22%). Among adult grafts, 92% were from peripheral blood and 8% were from bone marrow. A census of the bacterial species in each stool sample was generated by 16S rRNA deep-sequencing as previously described (Jenq et al., BiolBone Marrow Transplant 2015). The area under the curve of bacterial abundance over time was used as a measure of each patient's cumulative exposure to each bacterial taxon. Bacterial taxa of each patient present at a frequency >1% were evaluated for association with the outcome of relapse or progression of disease within the first year after allo-HSCT using linear discriminant analysis of effect size (LEfSe), a common approach in microbiota studies (Segata et al., Genome Biology, 2011). Among the taxons most significantly associated with freedom from relapse were members of the human oral flora including Streptococcus anginosus. After stratifying the patients by median abundance, we found that those with higher abundance of this bacterium had less relapse after transplantation (Left figure, p = 0.0014). We also identified bacteria associated with increased risk of relapse, such as Enterococcus faecium (Right figure, p = 0.0103). We evaluated these bacteria as biomarkers in multivariate Cox models adjusted for three factors that were associated with relapse in this cohort: Refined Disease Risk Index (RDRI, Armand et al., Blood 2014), conditioning intensity, and graft source (cord blood vs. adult donor). Streptococcus anginosus predicted relapse in a multivariate model adjusted for all three factors (HR 0.39, 95% CI 0.16-0.96, p = 0.041). Enterococcus faecium predicted relapse in a model adjusted for RDRI and conditioning intensity but failed to do so in a model additionally adjusted for graft source. In this analysis there was no formal adjustment for multiple comparisons; these data are now being validated in an additional cohort of patients whose samples are being sequenced. Finally, although we have previously reported that low bacterial diversity is associated with decreased overall survival after allo-HSCT (Taur et al., Blood 2014), we did not find an association between bacterial diversity and relapse as assessed by reciprocal Simpson diversity index (p > 0.1). Thus, the results of this retrospective analysis have identified an association between relapse after allo-HSCT and the abundance of two bacteria in the intestinal flora. These might serve as potential novel diagnostics or therapeutic targets to prevent relapse and improve overall survival after allo-HSCT. Figure 1. Figure 1. Disclosures Peled: Merck: Research Funding. Giralt:SANOFI: Consultancy, Honoraria, Research Funding; TAKEDA: Consultancy, Honoraria, Research Funding; AMGEN: Consultancy, Research Funding; JAZZ: Consultancy, Honoraria, Research Funding, Speakers Bureau; CELGENE: Consultancy, Honoraria, Research Funding. Perales:Merck: Honoraria; Takeda: Honoraria; Amgen: Honoraria; Astellas: Honoraria; NMDP: Membership on an entity's Board of Directors or advisory committees. van den Brink:Boehringer Ingelheim: Consultancy, Other: Advisory board attendee; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Tobira Therapeutics: Other: Advisory board attendee; Regeneron: Honoraria; Merck: Honoraria.

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