Natural history of clonal haematopoiesis seen in real-world haematology settings

Recursive partitioning of healthy consortia led to the development of the Clonal Hematopoiesis Risk Score (CHRS) for clonal haematopoiesis (CH); however, in the practical setting, most cases of CH are diagnosed after patients present with cytopenias or related symptoms. To address this real-world population, we characterize the clinical trajectories of 94 patients with CH and distinguish CH harbouring canonical DNMT3A/TET2/ASXL1 mutations alone ('sole DTA') versus all other groups ('non-sole DTA'). TET2, rather than DNMT3A, was the most prevalent mutation in the real-world setting. Sole DTA patients did not progress to myeloid neoplasm (MN) in the absence of acquisition of other mutations. Contrastingly, 14 (20.1%) of 67 non-sole DTA patients progressed to MN. CHRS assessment showed a higher frequency of high-risk CH in non-sole DTA (vs. sole DTA) patients and in progressors (vs. non-progressors). RUNX1 mutation conferred the strongest risk for progression to MN (odds ratio [OR] 10.27, 95% CI 2.00-52.69, p = 0.0053). The mean variant allele frequency across all genes was higher in progressors than in non-progressors (36.9% ± 4.62% vs. 24.1% ± 1.67%, p = 0.0064). This analysis in the post-CHRS era underscores the natural history of CH, providing insight into patterns of progression to MN.

Outpatient COVID-19 convalescent plasma recipient antibody thresholds correlated to reduced hospitalizations within a randomized trial

BACKGROUNDCOVID-19 convalescent plasma (CCP) virus-specific antibody levels that translate into recipient posttransfusion antibody levels sufficient to prevent disease progression are not defined.METHODSThis secondary analysis correlated donor and recipient antibody levels to hospitalization risk among unvaccinated, seronegative CCP recipients within the outpatient, double-blind, randomized clinical trial that compared CCP to control plasma. The majority of COVID-19 CCP arm hospitalizations (15/17, 88%) occurred in this unvaccinated, seronegative subgroup. A functional cutoff to delineate recipient high versus low posttransfusion antibody levels was established by 2 methods: (i) analyzing virus neutralization-equivalent anti-Spike receptor-binding domain immunoglobulin G (anti-S-RBD IgG) responses in donors or (ii) receiver operating characteristic (ROC) curve analysis.RESULTSSARS-CoV-2 anti-S-RBD IgG antibody was volume diluted 21.3-fold into posttransfusion seronegative recipients from matched donor units. Virus-specific antibody delivered was approximately 1.2 mg. The high-antibody recipients transfused early (symptom onset within 5 days) had no hospitalizations. A CCP-recipient analysis for antibody thresholds correlated to reduced hospitalizations found a statistical significant association between early transfusion and high antibodies versus all other CCP recipients (or control plasma), with antibody cutoffs established by both methods-donor-based virus neutralization cutoffs in posttransfusion recipients (0/85 [0%] versus 15/276 [5.6%]; P = 0.03) or ROC-based cutoff (0/94 [0%] versus 15/267 [5.4%]; P = 0.01).CONCLUSIONIn unvaccinated, seronegative CCP recipients, early transfusion of plasma units in the upper 30% of study donors' antibody levels reduced outpatient hospitalizations. High antibody level plasma units, given early, should be reserved for therapeutic use.TRIAL REGISTRATIONClinicalTrials.gov NCT04373460.FUNDINGDepartment of Defense (W911QY2090012); Defense Health Agency; Bloomberg Philanthropies; the State of Maryland; NIH (3R01AI152078-01S1, U24TR001609-S3, 1K23HL151826NIH); the Mental Wellness Foundation; the Moriah Fund; Octapharma; the Healthnetwork Foundation; the Shear Family Foundation; the NorthShore Research Institute; and the Rice Foundation.

COVID-19 convalescent plasma therapy decreases inflammatory cytokines: a randomized controlled trial

IMPORTANCE

This study examined the role that cytokines may have played in the beneficial outcomes found when outpatient individuals infected with SARS-CoV-2 were transfused with COVID-19 convalescent plasma (CCP) early in their infection. We found that the pro-inflammatory cytokine IL-6 decreased significantly faster in patients treated early with CCP. Participants with COVID-19 treated with CCP later in the infection did not have the same effect. This decrease in IL-6 levels after early CCP treatment suggests a possible role of inflammation in COVID-19 progression. The evidence of IL-6 involvement brings insight into the possible mechanisms involved in CCP treatment mitigating SARS-CoV-2 severity.

Outpatient COVID-19 convalescent plasma recipient antibody thresholds correlated to reduced hospitalizations within a randomized trial

BACKGROUND

The COVID-19 convalescent plasma (CCP) viral specific antibody levels that translate into recipient post-transfusion antibody levels sufficient to prevent disease progression is not defined.

METHODS

This secondary analysis correlated donor and recipient antibody levels to hospitalization risk among unvaccinated, seronegative CCP recipients within the outpatient, double blind, randomized clinical trial that compared CCP to control plasma. The majority of COVID-19 CCP arm hospitalizations (15/17, 88%) occurred in this unvaccinated, seronegative subgroup. A functional cutoff to delineate recipient high versus low post-transfusion antibody levels was established by two methods: 1) analyzing virus neutralization-equivalent anti-S-RBD IgG responses in donors or 2) receiver operating characteristic (ROC) analysis.

RESULTS

SARS-CoV-2 anti-S-RBD IgG antibody was diluted by a factor of 21.3 into post-transfusion seronegative recipients from matched donor units. Viral specific antibody delivered approximated 1.2 mg. The high antibody recipients transfused early (symptom onset within 5 days) had no hospitalizations. A CCP recipient analysis for antibody thresholds correlated to reduced hospitalizations found a significant association with Fisher's exact test between early and high antibodies versus all other CCP recipients (or control plasma) with antibody cutoffs established by both methods-donor virus neutralization-based cutoff: (0/85; 0% versus 15/276; 5.6%) p=0.03 or ROC based cutoff: (0/94; 0% versus 15/267; 5.4%) p=0.01.

CONCLUSION

In unvaccinated, seronegative CCP recipients, early transfusion of plasma units corresponding to the upper 30% of all study donors reduced outpatient hospitalizations. These high antibody level plasma units, given early, should be reserved for therapeutic use.Trial registration: NCT04373460.

FUNDING

Defense Health Agency and others.

Prognostic heterogeneity and clonal dynamics within distinct subgroups of myelodysplastic syndrome and acute myeloid leukemia with TP53 disruptions

TP53 aberrations constitute the highest risk subset of myelodysplastic neoplasms (MDS) and acute myeloid leukemia (AML). The International Consensus Classification questions the blast threshold between MDS and AML. In this study, we assess the distinction between MDS and AML for 76 patients with TP53 aberrations. We observed no significant differences between MDS and AML regarding TP53 genomics. Median overall survival (OS) was 223 days for the entire group, but prognostic discrimination within subgroups showed the most inferior OS (46 days) for AML with multihit allelic state plus TP53 variant allele frequency (VAF) > 50%. In multivariate analysis, unadjusted Cox models revealed the following variables as independent risk factors for mortality: AML (vs. MDS) (hazard ratio [HR]: 2.50, confidence interval [CI]: 1.4-4.4, p = 0.001), complex karyotype (HR: 3.00, CI: 1.4-6.1, p = 0.003), multihit status (HR: 2.30, CI 1.3-4.2, p = 0.005), and absence of hematopoietic cell transplant (HCT) (HR: 3.90, CI: 1.8-8.9, p = 0.0009). Clonal dynamic modeling showed a significant reduction in TP53 VAF with front-line hypomethylating agents. These findings clarify the impact of specific covariates on outcomes of TP53-aberrant myeloid neoplasms, irrespective of the diagnosis of MDS versus AML, and may influence HCT decisions.

Harnessing autologous immune effector mechanisms in acute myeloid leukemia: 2023 update of trials and tribulations

Numerous recent advances have been made in therapeutic approaches toward acute myeloid leukemia (AML). Since 2017, we have seen eleven novel Food & Drug Administration (FDA)-approved medications for AML, all of which extend beyond the classical cytarabine-based cytostatic chemotherapy. In the recent two decades, the role of immune surveillance in AML has been intensively investigated. The power of one's own innate and adaptive immunity has been harnessed pharmacologically toward the goal of clearance of AML cells. Specifically, pre-clinical studies have shown great promise for antibodies that disinhibit T cells and macrophages by blocking checkpoint receptors within the immunologic synapse, thereby resulting in the elimination of AML cells. Anti-CD33 CAR-T therapies and anti-CD3/CD123 bispecific antibodies have also exhibited encouraging results in pre-clinical and early clinical studies. However, despite these translational efforts, we currently have no immune-based therapies for AML on the market, with the exception of gemtuzumab ozogamicin. In this focused review, we discuss molecular target validation and the most relevant clinical updates for immune-based experimental therapeutics including anti-CD47 monoclonal antibodies, CAR-T therapies, and bispecific T cell engagers. We highlight barriers to the clinical translation of these therapies in AML, and we propose solutions to optimize the manufacturing and delivery of the most novel immune-based therapies in the pipeline.

Early antibody treatment, inflammation, and risk of post-COVID conditions

IMPORTANCE

Approximately 20% of individuals infected with SARS-CoV-2 experienced long-term health effects, as defined PCC. However, it is unknown if there are any early biomarkers associated with PCC or whether early intervention treatments may decrease the risk of PCC. In a secondary analysis of a randomized clinical trial, this study demonstrates that among outpatients with SARS-CoV-2, increased IL-6 at time of infection is associated with increased odds of PCC. In addition, among individuals treated early, within 5 days of symptom onset, with COVID-19 convalescent plasma, there was a trend for decreased odds of PCC after adjusting for other demographic and clinical characteristics. Future treatment studies should be considered to evaluate the effect of early treatment and anti-IL-6 therapies on PCC development.

Dynamics of inflammatory responses after SARS-CoV-2 infection by vaccination status in the USA: a prospective cohort study

BACKGROUND

Cytokines and chemokines play a critical role in the response to infection and vaccination. We aimed to assess the longitudinal association of COVID-19 vaccination with cytokine and chemokine concentrations and trajectories among people with SARS-CoV-2 infection.

METHODS

In this longitudinal, prospective cohort study, blood samples were used from participants enrolled in a multi-centre randomised trial assessing the efficacy of convalescent plasma therapy for ambulatory COVID-19. The trial was conducted in 23 outpatient sites in the USA. In this study, participants (aged ≥18 years) were restricted to those with COVID-19 before vaccination or with breakthrough infections who had blood samples and symptom data collected at screening (pre-transfusion), day 14, and day 90 visits. Associations between COVID-19 vaccination status and concentrations of 21 cytokines and chemokines (measured using multiplexed sandwich immunoassays) were examined using multivariate linear mixed-effects regression models, adjusted for age, sex, BMI, hypertension, diabetes, trial group, and COVID-19 waves (pre-alpha or alpha and delta).

FINDINGS

Between June 29, 2020, and Sept 30, 2021, 882 participants recently infected with SARS-CoV-2 were enrolled, of whom 506 (57%) were female and 376 (43%) were male. 688 (78%) of 882 participants were unvaccinated, 55 (6%) were partly vaccinated, and 139 (16%) were fully vaccinated at baseline. After adjusting for confounders, geometric mean concentrations of interleukin (IL)-2RA, IL-7, IL-8, IL-15, IL-29 (interferon-λ), inducible protein-10, monocyte chemoattractant protein-1, and tumour necrosis factor-α were significantly lower among the fully vaccinated group than in the unvaccinated group at screening. On day 90, fully vaccinated participants had approximately 20% lower geometric mean concentrations of IL-7, IL-8, and vascular endothelial growth factor-A than unvaccinated participants. Cytokine and chemokine concentrations decreased over time in the fully and partly vaccinated groups and unvaccinated group. Log10 cytokine and chemokine concentrations decreased faster among participants in the unvaccinated group than in other groups, but their geometric mean concentrations were generally higher than fully vaccinated participants at 90 days. Days since full vaccination and type of vaccine received were not correlated with cytokine and chemokine concentrations.

INTERPRETATION

Initially and during recovery from symptomatic COVID-19, fully vaccinated participants had lower concentrations of inflammatory markers than unvaccinated participants suggesting vaccination is associated with short-term and long-term reduction in inflammation, which could in part explain the reduced disease severity and mortality in vaccinated individuals.

FUNDING

US Department of Defense, National Institutes of Health, Bloomberg Philanthropies, State of Maryland, Mental Wellness Foundation, Moriah Fund, Octapharma, HealthNetwork Foundation, and the Shear Family Foundation.

Transfusion reactions associated with COVID-19 convalescent plasma in outpatient clinical trials

BACKGROUND

COVID-19 convalescent plasma (CCP) is an important therapeutic option for outpatients at high risk of hospitalization from SARS-CoV-2 infection. We assessed the safety of outpatient CCP transfusions administered during clinical trials.

STUDY DESIGN AND METHODS

We analyzed data pertaining to transfusion-related reactions from two randomized controlled trials in the U.S. that evaluated the efficacy of CCP versus control plasma in various ambulatory settings. Multivariable logistic regression was used to assess whether CCP was associated with transfusion reactions, after adjusting for potential confounders.

RESULTS

The combined study reported 79/1351 (5.9%) adverse events during the transfusion visit, with the majority 62/1351 (4.6%) characterized by mild, allergic-type findings of urticaria, and/or pruritus consistent with minor allergic transfusion reactions; the other reported events were attributed to the patients' underlying disease, COVID-19, or vasovagal in nature. We found no difference in the likelihood of allergic transfusion reactions between those receiving CCP versus control plasma (adjusted odds ratio [AOR], 0.75; 95% CI, 0.43-1.31). Risk of urticaria and/or pruritus increased with a pre-existing diagnosis of asthma (AOR, 2.33; 95% CI, 1.16-4.67). We did not observe any CCP-attributed antibody disease enhancement in participants with COVID-19 or increased risk of infection. There were no life-threatening severe transfusion reactions and no patients required hospitalization related to transfusion-associated complications.

DISCUSSION

Outpatient plasma administration was safely performed for nearly 1400 participants. CCP is a safe therapeutic option for outpatients at risk of hospitalization from COVID-19.

Early Treatment, Inflammation and Post-COVID Conditions

Background

Post-COVID conditions (PCC) are common and have significant morbidity. Risk factors for PCC include advancing age, female sex, obesity, and diabetes mellitus. Little is known about early treatment, inflammation, and PCC.

Methods

Among 883 individuals with confirmed SARS-CoV-2 infection participating in a randomized trial of CCP vs. control plasma with available biospecimens and symptom data, the association between early COVID treatment, cytokine levels and PCC was evaluated. Cytokine and chemokine levels were assessed at baseline, day 14 and day 90 using a multiplexed sandwich immuosassay (Mesoscale Discovery). Presence of any self-reported PCC symptoms was assessed at day 90. Associations between COVID treatment, cytokine levels and PCC were examined using multivariate logistic regression models.

Results

One-third of the 882 participants had day 90 PCC symptoms, with fatigue (14.5%) and loss of smell (14.5%) being most common. Cytokine levels decreased from baseline to day 90. In a multivariable analysis including diabetes, body mass index, race, and vaccine status, female sex (adjusted odds ratio[AOR]=2.70[1.93-3.81]), older age (AOR=1.32[1.17-1.50]), and elevated baseline levels of IL-6 (AOR=1.59[1.02-2.47]) were associated with development of PCC.There was a trend for decreased PCC in those with early CCP treatment (≤5 days after symptom onset) compared to late CCP treatment.

Conclusion

Increased IL-6 levels were associated with the development of PCC and there was a trend for decreased PCC with early CCP treatment in this predominately unvaccinated population. Future treatment studies should evaluate the effect of early treatment and anti-IL-6 therapies on PCC development.

Convalescent plasma with a high level of virus-specific antibody effectively neutralizes SARS-CoV-2 variants of concern

The ongoing evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants severely limits available effective monoclonal antibody therapies. Effective drugs are also supply limited. COVID-19 convalescent plasma (CCP) qualified for high antibody levels effectively reduces immunocompetent outpatient hospitalization. The Food and Drug Administration currently allows outpatient CCP for the immunosuppressed. Viral-specific antibody levels in CCP can range 10- to 100-fold between donors, unlike the uniform viral-specific monoclonal antibody dosing. Limited data are available on the efficacy of polyclonal CCP to neutralize variants. We examined 108 pre-δ/pre-ο donor units obtained before March 2021, 20 post-δ COVID-19/postvaccination units, and 1 pre-δ/pre-ο hyperimmunoglobulin preparation for variant-specific virus (vaccine-related isolate [WA-1], δ, and ο) neutralization correlated to Euroimmun S1 immunoglobulin G antibody levels. We observed a two- to fourfold and 20- to 40-fold drop in virus neutralization from SARS-CoV-2 WA-1 to δ or ο, respectively. CCP antibody levels in the upper 10% of the 108 donations as well as 100% of the post-δ COVID-19/postvaccination units and the hyperimmunoglobulin effectively neutralized all 3 variants. High-titer CCP neutralizes SARS-CoV-2 variants despite no previous donor exposure to the variants.

Early Outpatient Treatment for Covid-19 with Convalescent Plasma

BACKGROUND

Polyclonal convalescent plasma may be obtained from donors who have recovered from coronavirus disease 2019 (Covid-19). The efficacy of this plasma in preventing serious complications in outpatients with recent-onset Covid-19 is uncertain.

METHODS

In this multicenter, double-blind, randomized, controlled trial, we evaluated the efficacy and safety of Covid-19 convalescent plasma, as compared with control plasma, in symptomatic adults (≥18 years of age) who had tested positive for severe acute respiratory syndrome coronavirus 2, regardless of their risk factors for disease progression or vaccination status. Participants were enrolled within 8 days after symptom onset and received a transfusion within 1 day after randomization. The primary outcome was Covid-19-related hospitalization within 28 days after transfusion.

RESULTS

Participants were enrolled from June 3, 2020, through October 1, 2021. A total of 1225 participants underwent randomization, and 1181 received a transfusion. In the prespecified modified intention-to-treat analysis that included only participants who received a transfusion, the primary outcome occurred in 17 of 592 participants (2.9%) who received convalescent plasma and 37 of 589 participants (6.3%) who received control plasma (absolute risk reduction, 3.4 percentage points; 95% confidence interval, 1.0 to 5.8; P = 0.005), which corresponded to a relative risk reduction of 54%. Evidence of efficacy in vaccinated participants cannot be inferred from these data because 53 of the 54 participants with Covid-19 who were hospitalized were unvaccinated and 1 participant was partially vaccinated. A total of 16 grade 3 or 4 adverse events (7 in the convalescent-plasma group and 9 in the control-plasma group) occurred in participants who were not hospitalized.

CONCLUSIONS

In participants with Covid-19, most of whom were unvaccinated, the administration of convalescent plasma within 9 days after the onset of symptoms reduced the risk of disease progression leading to hospitalization. (Funded by the Department of Defense and others; CSSC-004 ClinicalTrials.gov number, NCT04373460.).

High Viral Specific Antibody Convalescent Plasma Effectively Neutralizes SARS-CoV-2 Variants of Concern

The ongoing evolution of SARS-Co-V2 variants to omicron severely limits available effective monoclonal antibody therapies. Effective drugs are also supply limited. Covid-19 convalescent plasma (CCP) qualified for high antibody levels effectively reduces immunocompetent outpatient hospitalization. The FDA currently allows outpatient CCP for the immunosuppressed. Viral specific antibody levels in CCP can range ten-to hundred-fold between donors unlike the uniform viral specific monoclonal antibody dosing. Limited data are available on the efficacy of polyclonal CCP to neutralize variants. We examined 108 pre-delta/pre-omicron donor units obtained before March 2021, 20 post-delta COVID-19/post-vaccination units and one pre-delta/pre-omicron hyperimmunoglobulin preparation for variant specific virus (vaccine-related isolate (WA-1), delta and omicron) neutralization correlated to Euroimmun S1 IgG antibody levels. We observed a 2-to 4-fold and 20-to 40-fold drop in virus neutralization from SARS-CoV-2 WA-1 to delta or omicron, respectively. CCP antibody levels in the upper 10% of the 108 donations as well as 100% of the post-delta COVID-19/post-vaccination units and the hyperimmunoglobulin effectively neutralized all three variants. High-titer CCP neutralizes SARS-CoV-2 variants despite no previous donor exposure to the variants.

Key points

All of the post-delta COVID-19/post vaccination convalescent plasma effectively neutralizes the omicron and delta variants.High-titer CCP and hyperimmunoglobulin neutralizes SARS-CoV-2 variants despite no previous donor exposure to the variants.

Randomized Controlled Trial of Early Outpatient COVID-19 Treatment with High-Titer Convalescent Plasma

BACKGROUND

The efficacy of polyclonal high titer convalescent plasma to prevent serious complications of COVID-19 in outpatients with recent onset of illness is uncertain.

METHODS

This multicenter, double-blind randomized controlled trial compared the efficacy and safety of SARS-CoV-2 high titer convalescent plasma to placebo control plasma in symptomatic adults ≥18 years positive for SARS-CoV-2 regardless of risk factors for disease progression or vaccine status. Participants with symptom onset within 8 days were enrolled, then transfused within the subsequent day. The measured primary outcome was COVID-19-related hospitalization within 28 days of plasma transfusion. The enrollment period was June 3, 2020 to October 1, 2021.

RESULTS

A total of 1225 participants were randomized and 1181 transfused. In the pre-specified modified intention-to-treat analysis that excluded those not transfused, the primary endpoint occurred in 37 of 589 (6.3%) who received placebo control plasma and in 17 of 592 (2.9%) participants who received convalescent plasma (relative risk, 0.46; one-sided 95% upper bound confidence interval 0.733; P=0.004) corresponding to a 54% risk reduction. Examination with a model adjusting for covariates related to the outcome did not change the conclusions.

CONCLUSION

Early administration of high titer SARS-CoV-2 convalescent plasma reduced outpatient hospitalizations by more than 50%. High titer convalescent plasma is an effective early outpatient COVID-19 treatment with the advantages of low cost, wide availability, and rapid resilience to variant emergence from viral genetic drift in the face of a changing pandemic.

Trial Registration

ClinicalTrials.gov number, NCT04373460.

Clinico-genomic profiling and clonal dynamic modeling of TP53-aberrant myelodysplastic syndrome and acute myeloid leukemia

TP53-aberrant myelodysplastic syndrome and acute myeloid leukemia have dismal outcomes. Here, we define the clinico-genomic landscape of TP53 disruptions in 40 patients and employ clonal dynamic modeling to map the mutational hierarchy against clinical outcomes. Most TP53 mutations (45.2%) localized to the L3 loop or LSH motif of the DNA-binding domain. TP53 disruptions had high co-occurrence with mutations in epigenetic regulators, spliceosome machinery, and cohesin complex and low co-occurrence with mutations in proliferative signaling genes. Ancestral and descendant TP53 mutations constituted measurable residual disease and fueled relapse. High mutant TP53 gene dosage predicted low durability of remission. The median overall survival (OS) was 280 days. Hypomethylating agent-based therapy served as an effective bridge to transplant, leading to improved median OS compared to patients who did not receive a transplant (14.7 vs. 5.1 months). OS was independent of the genomic location of TP53 disruption, which has implications for rational therapeutic design.

Comanagement Strategy Between Academic Institutions and Community Practices to Reduce Induction Mortality in Acute Promyelocytic Leukemia

Acute promyelocytic leukemia (APL) is a curable leukemia with > 90% survival in clinical trials. Population-based studies from Sweden and US SEER data have shown long-term survival rates of 62% and 65.7%, with the lower rate being from a higher percentage of early deaths.

Abstract 1920: Response to hypomethylating agents based on cytidine deaminase expression, genetic polymorphisms, and NPM1 mutation status in acute myeloid leukemia

Response to hypomethylating agents (HMAs) in patients (pts) with acute myeloid leukemia (AML) is variable. Data on biological predictors of response is limited. Cytidine deaminase (CDA) inactivates HMAs. Increased CDA activity may lead to HMA resistance. Using core pathway analysis, we identified nucleophosmin 1 (NPM1) indirectly influences CDA expression. We hypothesized that responses to HMAs occur in the setting of decreased CDA expression regulated by NPM1 and investigated the relationship between NPM1 status, CDA expression, single nucleotide polymorphisms (SNPs) in CDA, and HMA response in pts with AML.

AML pts with banked samples who received HMA-based therapy between 1/2014 to 12/2018 were reviewed. Responses following at least 2 cycles of HMA were categorized as responders (R) or non-responders (NR). Pt, disease, NPM1 status, and treatment characteristics were summarized. CDA gene and protein expression was examined in bone marrow and peripheral blood samples at diagnosis using qRT-PCR and CDA sandwich ELISA, respectively. CDA gene expression levels were normalized to the housekeeping gene, 18s, and the comparative CT method was used to assess expression. Comparisons based on response and NPM1 mutation status were performed using the Mann-Whitney U test. 17 SNPs previously shown to alter CDA activity were selected for analysis. SNPs were determined using real-time PCR with allele specific probes; longer insertions/deletions were identified by sanger sequencing. Univariate logistic regression analysis was performed to discern the association between SNPs in CDA and response to HMAs.

54 pts had available blood, marrow, or buccal samples available for analysis. 33 pts provided blood or marrow samples for gene and protein analysis prior to HMA. 22 pts (67%) were classified as R in this cohort. 35 pts had available buccal swabs for genotyping, and 28 pts (80%) were classified as R. Median OS was 21 months (mo) for all pts, 23 mo among R, and 18 mo in NR. CDA expression was significantly decreased in NPM1 wild type pts compared to NPM1 mutant pts (p=0.02) but did not differ in R compared to NR. No significant differences were identified in CDA protein expression based on NPM1 status or response. No SNPs were significantly associated with response.

Baseline CDA gene expression in bulk tumor cells was significantly lower in NPM1 wild type pts compared to NPM1 mutant pts but no different between pts responding to HMAs compared to NR. There was no clear correlation between CDA protein expression and NPM1 status or response. None of the CDA SNPs were predictive of response to HMAs. This analysis reveals feasibility of assessing CDA activity in this population. Our small sample size limits our ability to determine CDA activity as a biological predictor of response, and ongoing pt accrual will allow for further exploration of the role of CDA in HMA response.

Citation Format: Brittany Knick Ragon, Issam S. Hamadeh, C Greer Vestal, Alicia Hamilton, Mathew L. Smith, Danielle Boselli, Jing Ai, Thomas G. Knight, Michael R. Grunwald, Jonathan M. Gerber, Edward A. Copelan, Lawrence J. Druhan, Belinda R. Avalos, Nury M. Steuerwald, Jai N. Patel. Response to hypomethylating agents based on cytidine deaminase expression, genetic polymorphisms, and NPM1 mutation status in acute myeloid leukemia [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1920.

Elotuzumab-based maintenance therapy following autologous stem cell transplant in multiple myeloma deepens post-transplant responses

BACKGROUND

Post-transplant maintenance provides progression-free survival benefit in multiple myeloma (MM). Here we report our institution's experience with elotuzumab-based maintenance following autologous stem cell transplant.

METHODS

We retrospectively evaluated the outcomes of MM patients who were started on elotuzumab-based maintenance (elotuzumab/lenalidomide/dexamethasone, elotuzumab/bortezomib/dexamethasone, or elotuzumab/bortezomib/methylprednisolone) following transplant (N = 7). Baseline characteristics, treatment response, survival, and adverse events were reviewed.

RESULTS

Median age was 68 (56-81) years at the time of transplant, and median lines of induction therapy was 2 (1-6). Three patients (42.9%) had high-risk cytogenetics and five (71.4%) had stage II or greater disease at diagnosis. At a median follow-up of 24 months (12-50), five patients (71.4%) had improvement of quality of response, with a combined CR or VGPR rate increasing from 57.1% to 100% (CR = 3, VGPR = 4). All patients were alive without relapse or progression at the time of this analysis. Grade 3-4 adverse events were observed in three (42.9%) patients. None of the patients discontinued the treatment due to intolerance.

CONCLUSIONS

Our study demonstrates that elotuzumab-based maintenance may deepen response post-transplant in MM and can be safely administered even in older patients. Given its unique action and rare side effects, further studies of elotuzumab in the post-transplant setting are warranted.

A User's Guide to Novel Therapies for Acute Myeloid Leukemia

Few diseases have been marked by a 40-year period of stagnation with regard to therapeutic advances and United States Food and Drug Administration (FDA) approvals, as has been the case for acute myeloid leukemia (AML). Cytarabine and anthracyclines were introduced for the treatment of AML in the 1970s, and in the ensuing 4 decades, the pharmacologic pipeline has experienced a standstill. The absence of FDA approvals in AML is not a reflection of the lack of understanding of the disease biology. The field has seen major advances from the standpoint of stem cell biology and clonal evolution, and the field has also seen some therapeutic advances, but these therapeutic advances have arisen from optimization of the same traditional cytotoxic chemotherapeutics rather than the development of novel therapies. The year 2017 marked a turning point with regard to FDA approvals. This review summarizes the salient clinical trials that led to the approval of 8 novel agents in AML in the past 2 years. For these agents, the clinical activity is often defined by specific molecular aberrations or metabolic features of AML cells. We also emphasize the principles of management of AML in the current era of genomic medicine, with a focus on considerations for targeting mutation-specific vulnerabilities in select patients. This review also highlights unique challenges to the use of novel agents in 2020, including considerations of curative potential with regards to bridging to allogeneic stem cell transplant, tolerability, financial toxicities, and microenvironmental hurdles. Finally, we discuss prospects on future immunotherapeutic investigational agents in the pharmacologic pipeline.

Microgranular acute promyelocytic leukemia presenting with leukopenia and an unusual immunophenotype

The microgranular variant (M3v) of acute promyelocytic leukemia (APL) is rare, and the diagnosis can be delayed due to variability in how this condition presents. M3v blasts often have folded nuclei, but unlike traditional APL blasts, they often possess faint granules without Auer rods. In addition, microgranular APL often presents with an elevated or normal white blood cell count in contrast with the leukopenia seen in traditional APL. In APL, delayed diagnosis can lead to early death from disseminated intravascular coagulation (DIC), which is the main cause of mortality in an otherwise treatable, and often curable, leukemia. We describe a 19-year-old male with microgranular APL who presented with leukopenia and many blasts resembling non-APL AML blasts with an unexpected immunophenotypic pattern. He was treated for DIC and initiated on all-trans-retinoic acid and arsenic trioxide; he achieved complete molecular remission after induction therapy. Suspicion for APL should always remain high in the presence of clinical manifestations of the disease in order that appropriate treatment can be initiated rapidly to prevent early death.

Leucine Rich α-2 Glycoprotein: A Novel Neutrophil Granule Protein and Modulator of Myelopoiesis

Leucine-rich α2 glycoprotein (LRG1), a serum protein produced by hepatocytes, has been implicated in angiogenesis and tumor promotion. Our laboratory previously reported the expression of LRG1 in murine myeloid cell lines undergoing neutrophilic granulocyte differentiation. However, the presence of LRG1 in primary human neutrophils and a role for LRG1 in regulation of hematopoiesis have not been previously described. Here we show that LRG1 is packaged into the granule compartment of human neutrophils and secreted upon neutrophil activation to modulate the microenvironment. Using immunofluorescence microscopy and direct biochemical measurements, we demonstrate that LRG1 is present in the peroxidase-negative granules of human neutrophils. Exocytosis assays indicate that LRG1 is differentially glycosylated in neutrophils, and co-released with the secondary granule protein lactoferrin. Like LRG1 purified from human serum, LRG1 secreted from activated neutrophils also binds cytochrome c. We also show that LRG1 antagonizes the inhibitory effects of TGFβ1 on colony growth of human CD34⁺ cells and myeloid progenitors. Collectively, these data invoke an additional role for neutrophils in innate immunity that has not previously been reported, and suggest a novel mechanism whereby neutrophils may modulate the microenvironment via extracellular release of LRG1.

Cutaneous manifestations in leukemia patients

Cutaneous complications are common in patients with leukemia. However, the cause is not always immediately clear, as there are often numerous potential etiologies. Thrombocytopenia or coagulopathy can result in ecchymoses or petechiae, whereas extramedullary (EM) involvement by leukemia can present as a rash. Leukemia can also result in skin manifestations via indirect means, including several types of paraneoplastic phenomena. Moreover, various agents routinely used to treat leukemia-most notably cytarabine (cytosine arabinoside)-can precipitate quite profound skin eruptions. Finally, infections, including fungal invasion of the skin, can be responsible for rashes, as can the vast array of antimicrobials that are administered to leukemia patients.

Association of acute myeloid leukemia's most immature phenotype with risk groups and outcomes

The precise phenotype and biology of acute myeloid leukemia stem cells remain controversial, in part because the "gold standard" immunodeficient mouse engraftment assay fails in a significant fraction of patients and identifies multiple cell-types in others. We sought to analyze the clinical utility of a novel assay for putative leukemia stem cells in a large prospective cohort. The leukemic clone's most primitive hematopoietic cellular phenotype was prospectively identified in 109 newly-diagnosed acute myeloid leukemia patients, and analyzed against clinical risk groups and outcomes. Most (80/109) patients harbored CD34(+)CD38(-) leukemia cells. The CD34(+)CD38(-) leukemia cells in 47 of the 80 patients displayed intermediate aldehyde dehydrogenase expression, while normal CD34(+)CD38(-) hematopoietic stem cells expressed high levels of aldehyde dehydrogenase. In the other 33/80 patients, the CD34(+)CD38(-) leukemia cells exhibited high aldehyde dehydrogenase activity, and most (28/33, 85%) harbored poor-risk cytogenetics or FMS-like tyrosine kinase 3 internal tandem translocations. No CD34(+) leukemia cells could be detected in 28/109 patients, including 14/21 patients with nucleophosmin-1 mutations and 6/7 acute promyelocytic leukemia patients. The patients with CD34(+)CD38(-) leukemia cells with high aldehyde dehydrogenase activity manifested a significantly lower complete remission rate, as well as poorer event-free and overall survivals. The leukemic clone's most immature phenotype was heterogeneous with respect to CD34, CD38, and ALDH expression, but correlated with acute myeloid leukemia risk groups and outcomes. The strong clinical correlations suggest that the most immature phenotype detectable in the leukemia might serve as a biomarker for "clinically-relevant" leukemia stem cells. ClinicalTrials.gov: NCT01349972.

Genome-wide comparison of the transcriptomes of highly enriched normal and chronic myeloid leukemia stem and progenitor cell populations

The persistence leukemia stem cells (LSCs) in chronic myeloid leukemia (CML) despite tyrosine kinase inhibition (TKI) may explain relapse after TKI withdrawal. Here we performed genome-wide transcriptome analysis of highly refined CML and normal stem and progenitor cell populations to identify novel targets for the eradication of CML LSCs using exon microarrays. We identified 97 genes that were differentially expressed in CML versus normal stem and progenitor cells. These included cell surface genes significantly upregulated in CML LSCs: DPP4 (CD26), IL2RA (CD25), PTPRD, CACNA1D, IL1RAP, SLC4A4, and KCNK5. Further analyses of the LSCs revealed dysregulation of normal cellular processes, evidenced by alternative splicing of genes in key cancer signaling pathways such as p53 signaling (e.g. PERP, CDKN1A), kinase binding (e.g. DUSP12, MARCKS), and cell proliferation (MYCN, TIMELESS); downregulation of pro-differentiation and TGF-β/BMP signaling pathways; upregulation of oxidative metabolism and DNA repair pathways; and activation of inflammatory cytokines, including CCL2, and multiple oncogenes (e.g., CCND1). These data represent an important resource for understanding the molecular changes in CML LSCs, which may be exploited to develop novel therapies for eradication these cells and achieve cure.

Software-automated counting of Ki-67 proliferation index correlates with pathologic grade and disease progression of follicular lymphomas

OBJECTIVES

To examine the accuracy of software-assisted measurement of the Ki-67 proliferation index (PI) and its correlation with the grade and clinical progression of follicular lymphoma (FL).

METHODS

High-power field equivalents were extracted from H&E- and Ki-67-immunostained slides of FL, and a nuclear quantitation algorithm was used to calculate a PI. Representative fields were manually counted for validation with close agreement.

RESULTS

The PI was significantly higher in World Health Organization grade 3 FL than grade 1 to 2 FL. Disease progression, as defined by subsequent treatment with radiation or cytotoxic chemotherapy, was also significantly associated with elevated PI but not pathologic grade.

CONCLUSIONS

These data show that software-automated quantitation of Ki-67 can provide both a useful adjunct to pathologic grade in FL and improved prognostic information for patients.

Characterization of chronic myeloid leukemia stem cells

Although tyrosine kinase inhibitors have redefined the care of chronic myeloid leukemia (CML), these agents have not proved curative, likely due to resistance of the leukemia stem cells (LSC). While a number of potential therapeutic targets have emerged in CML, their expression in the LSC remains largely unknown. We therefore isolated subsets of CD34(+) stem/progenitor cells from normal donors and from patients with chronic phase or blast crisis CML. These cell subsets were then characterized based on ability to engraft immunodeficient mice and expression of candidate therapeutic targets. The CD34(+)CD38(-) CML cell population with high aldehyde dehydrogenase (ALDH) activity was the most enriched for immunodeficient mouse engrafting capacity. The putative targets: PROTEINASE 3, SURVIVIN, and hTERT were expressed only at relatively low levels by the CD34(+)CD38(-)ALDH(high) CML cells, similar to the normal CD34(+)CD38(-)ALDH(high) cells and less than in the total CML CD34(+) cells. In fact, the highest expression of these antigens was in normal, unfractionated CD34(+) cells. In contrast, PRAME and WT1 were more highly expressed by all CML CD34(+) subsets than their normal counterparts. Thus, ALDH activity appears to enrich for CML stem cells, which display an expression profile that is distinct from normal stem/progenitor cells and even the CML progenitors. Indeed, expression of a putative target by the total CD34(+) population in CML does not guarantee expression by the LSC. These expression patterns suggest that PROTEINASE 3, SURVIVIN, and hTERT are not optimal therapeutic targets in CML stem cells; whereas PRAME and WT1 seem promising.

Occupational asthma caused by chloramines in indoor swimming-pool air

The first series of three workers who developed occupational asthma following exposure to airborne chloramines in indoor chlorinated swimming pools is reported. Health problems of swimmers in indoor pools have traditionally been attributed to the chlorine in the water. Chlorine reacts with bodily proteins to form chloramines; the most volatile and prevalent in the air above swimming pools is nitrogen trichloride. Two lifeguards and one swimming teacher with symptoms suggestive of occupational asthma kept 2-hourly measurements of peak expiratory flow at home and at work, analysed using the occupational asthma system (OASYS) plotter, and/or had specific bronchial challenge testing to nitrogen trichloride, or a workplace challenge. Air measurement in one of the pools showed the nitrogen trichloride levels to be 0.1-0.57 mg x m(-3), which was similar to other studies. Two workers had peak expiratory flow measurements showing occupational asthma (OASYS-2 scores 2.88 and 3.8), both had a positive specific challenge to nitrogen trichloride at 0.5 mg x m(-3) with negative challenges to chlorine released from sodium hypochlorite. The third worker had a positive workplace challenge. Swimming-pool asthma due to airborne nitrogen trichloride can occur in workers who do not enter the water because of this chloramine. The air above indoor swimming pools therefore needs to be assessed and managed as carefully as the water.

Measuring the emission rate of an aerosol source placed in a ventilated room using a tracer gas: influence of particle wall deposition

A method to measure the emission rate of an airborne pollutant source using a tracer gas was tested in the case of an aerosol source. The influence of particle deposition on the walls of a test room of 72 m3 was studied. The deposition rate of an aerosol of MgCl2 was determined by means of two methods: one based on measuring the aerosol concentration decay inside the ventilated room, the other based on calculation of the material mass balance. The concentration decay was monitored by optical counting and the aerosol mass concentration determined by means of sampling on a filter and analysis of the mass deposited by atomic absorption spectrometry. Four series of measurements were carried out. The curve giving the deposition rate according to the particle aerodynamic diameter (d(ae)) was established and shows deposition rates higher than those predicted using the model of Corner. The decay method gives the best results. The study carried out has shown that the phenomenon of deposition has little effect on the measurement of the aerosol source emission rate using a tracer gas for particles of aerodynamic diameter < 5 microm (underestimation < 25%). For particles of a greater diameter, wall deposition is an extremely limiting factor for the method, the influence of which can, however, be limited by using a test booth of small volume and keeping the sampling duration as short as possible.

Exposure to chloramines in a green salad processing plant

Acute eye and upper respiratory irritation was reported at an industrial facility that processes green salads in water containing hypochlorite. The irritant agents were chloramines resulting from the reaction of hypochlorite and nitrogen compounds coming from the sap proteins released when the vegetables were cut. Specific sampling and analytical methods were developed in order to assess the workers' exposure. Monochloramine, dichloramine and nitrogen trichloride were found in the atmosphere, which can explain the irritation phenomena of which the workers complained. In the washing room (where salads are processed), the total chloramine concentration ranged from 0.4 to 16 mg.m-3, depending on the day and the location of the area sampling points. The exposure of workers determined by personal sampling ranged from 0.2 to 5 mg.m-3. In a previous study, with swimming pool instructors exposed to the same pollutants, irritation phenomena generally appeared at chloramine values of around 0.5 mg.m-3.

Stress affects corticosteroid and immunoglobulin concentrations in male house mice (Mus musculus) and prairie voles (Microtus ochrogaster)

Glucocorticoids, secreted in response to perceived stress, can suppress immunoglobulin (Ig) levels and compromise immune function in mice and rats. Prairie voles (Microtus ochrogaster) have been reported to exhibit basal corticosterone concentrations that would cause pathological changes in the immune function of most other rodents. The goals of the present study were to verify that serum corticosterone concentrations are high in prairie voles, as compared with house mice (Mus musculus), by measuring serum corticosterone with the same RIA; to examine the effects of mild stressors on corticosterone response in both species and to examine the effects of elevated corticosterone levels on IgM and IgG levels in prairie voles and house mice. After 2 weeks of randomly timed 15-min daily restraint or cold-water swim sessions, animals were injected with sheep red blood cells. The data confirmed that basal blood concentrations of corticosterone were higher in prairie voles than house mice, but these high levels doubled after the first swim session in prairie voles, indicating that the adrenals can respond to stressors by producing increased corticosterone. After stress, antibody production (both IgM and IgG) was reduced in house mice but not in prairie voles, despite higher blood concentrations of glucocorticoids in prairie voles. Although body mass was statistically equivalent between species, prairie voles and mice differed dramatically in adrenal and splenic masses. Average adrenal mass of prairie voles was approximately three times the average mass of these organs in house mice; in contrast, the average splenic mass of house mice was approximately three times that of prairie voles. These data may be relevant to seasonal changes in immune function and survival.

Photoperiodic effects on steroid negative feedback in female prairie voles (Microtus ochrogaster)

Breeding in prairie voles is mainly restricted to the autumn and winter of most years. The organization of estrus in female prairie voles is unusual because behavioral estrus is induced by chemosensory stimuli from the urine of adult conspecific males. Isolated females exhibit undetectable levels of estradiol and never display estrous behavior, yet exposure to male urine causes a cascade of endocrine changes that evoke estrogen secretion from the ovaries and estrous behavior within 24 hr. In the prairie vole, the extreme dependence of estrus on chemosensory stimuli raises the possibility that their ovaries may be less prominent in the regulation of gonadotropin secretion than in species with more endogenously organized estrous cycles. The present study examined the contribution of the ovaries in luteinizing hormone (LH) regulation in prairie voles. Females were maintained for 9 weeks in either long (LD 16:8) or short (LD 8:16) photoperiodic conditions, a blood sample was obtained, and then animals were either ovariectomized or received a sham procedure. Another blood sample was obtained a week later and assayed for serum LH. Blood serum LH levels were significantly reduced in short-day voles, compared to long-day animals. After ovariectomy both long-day and short-day voles exhibited equivalent elevations in LH levels. This study provides evidence that photoperiod is measured in female voles and the ovaries appear to produce sufficient steroids to suppress LH release.

Day length affects immune cell numbers in deer mice: interactions with age, sex, and prenatal photoperiod

The extent to which day length affects immune function was examined in the present study. Three goals were pursued: 1) to confirm and extend the observation that the immune systems of adult deer mice (Peromyscus maniculatus) are responsive to changes in photoperiod, 2) to examine the development of the photoperiod-associated changes in immune function, and 3) to discover whether photoperiodic information transmitted to the young during gestation influences immune function. In experiment 1, adult mice housed in short days had higher white blood cell and lymphocyte numbers than their long-day cohorts. Red blood cell and differential cell counts did not differ between long- and short-day animals. No sex differences were observed in the pattern of immune responses to photoperiod. The effect of photoperiod on immune cells in prepubertal animals was examined in experiment 2; a similar pattern of results was obtained as that for experiment 1, suggesting that the photoperiodic effect on the immune system is not mediated by sex steroid hormones. Prenatal and postnatal photoperiodic effects on immune cells were examined in experiment 3; pups gestated in one day length were cross-fostered to mothers in the same day length conditions or to mothers maintained in the alternative day length. The results of experiment 3 suggested that photoperiodic information transmitted from the mother to the young in utero subsequently affected immune systems of the pups. Animals gestated in short day lengths displayed higher immune status throughout life than mice gestated in long days. These results are discussed from an adaptive functional perspective.

Conservative treatment of calcific trochanteric bursitis

OBJECTIVE

To present a case of conservatively managed calcific trochanteric bursitis and discuss differential diagnosis and treatment alternatives.

CLINICAL FEATURES

A 53-yr-old obese female presented with acute severe lateral hip and posterolateral thigh pain. Examination findings were consistent with trochanteric bursitis and radiographs demonstrated calcific infiltration of the trochanteric bursa.

INTERVENTION AND OUTCOME

An intensive 2-wk course of pulsed ultrasound, ice massage, interferential current and chiropractic lumbopelvic manipulation resulted in symptomatic relief, abolishment of palpatory tenderness and return of pain-free passive and resisted range of motion of the hip.

CONCLUSIONS

Trochanteric bursitis is a common cause of hip pain. A trial of conservative measures is warranted for this condition, even when calcinosis is present, before more invasive therapies are considered.

Exposure to metallic catalyst dust: manufacturing and handling of catalysts in the chemical industry

The exposure of workers to metallic catalyst dust was assessed in manufacturing and reprocessing industries, and during catalyst handling in the chemical industry. The level of exposure was found to be generally low during the manufacturing and reprocessing activities taking place in permanent installations, and extremely variable during catalyst handling performed by workers of sub-contracting specialized firms. The difficulties in treating the occupational hygiene problems of these workers are pointed out.

Exposure to sulphuric acid and sulphur dioxide in the manufacturing of titanium dioxide

An assessment of exposure to sulphuric acid and sulphur dioxide was performed in the French titanium dioxide manufacturing industry. The three plants use the sulphuric acid process, with potential exposure mainly to sulphur dioxide and sulphuric acid. The exposures found were below the French limit values, except for some employees using the Moore filtration process in one plant. For sulphuric acid sampling, a comparison was made between thoracic particulate mass and inhalable particulate mass, from samples taken with a Marple cascade impactor. This comparison shows that the suggested new limit value (0.1 mg m-3 in thoracic particulate mass) would be much more severe than the present one (1.0 mg m-3 with no restriction as to the droplet size).

Calcification of vas deferens associated with diabetes mellitus

Calcification of the vas deferens may be associated with diabetes mellitus. This paper discusses the case of a patient in which this occurred. In clinical practice, this radiological finding may indicate further diagnostic workup for diabetes or other causative conditions which are described here.