Diagnostic capabilities, clinical features, and longitudinal UBA1 clonal dynamics of a nationwide VEXAS cohort.

VEXAS is a prototypic hemato-inflammatory disease combining rheumatologic and hematologic disorders in a molecularly defined nosological entity. In this nationwide study, we aimed at screenshotting the current diagnostic capabilities and clinical-genomic features of VEXAS, and tracked UBA1 longitudinal clonal dynamics upon different therapeutics, including allogeneic hematopoietic cell transplant. We leveraged a collaboration between the Italian Society of Experimental Hematology and of Rheumatology and disseminated a national survey to collect clinical and molecular patient information. Overall, 13/29 centers performed UBA1 genomic testing locally, including Sanger sequencing (46%), next-generation sequencing (23%), droplet digital polymerase chain reaction (8%), or combination (23%). A total of 41 male patients were identified, majority (51%) with threonine substitutions at Met41 hotspot, followed by valine and leucine (27% and 8%). Median age at VEXAS diagnosis was 67 years. All patients displayed anemia (median hemoglobin 9.1 g/dL), with macrocytosis. Bone marrow vacuoles were observed in most cases (89%). The most common rheumatologic association was polychondritis (49%). A concomitant myelodysplastic neoplasm/syndrome (MDS) was diagnosed in 71% of patients (n = 28), chiefly exhibiting lower Revised International Prognostic Scoring System risk profiles. Karyotype was normal in all patients, except three MDS cases showing -Y, t(12;16)(q13;q24), and +8. The most frequently mutated gene was DNMT3A (n = 10), followed by TET2 (n = 3). At last follow-up, five patients died and two patients progressed to acute leukemia. Longitudinal UBA1 clonal dynamics demonstrated mutational clearance following transplant. We collected a nationwide interdisciplinary VEXAS patient cohort, characterized by heterogeneous rheumatologic manifestations and treatments used. MDS was diagnosed in 71% of cases. Patients exhibited various longitudinal UBA1 clonal dynamics.

Mitapivat for sickle cell disease and thalassemia.

Mitapivat, an oral first-in-class activator of erythrocyte pyruvate kinase (PKR), was first investigated in patients with pyruvate kinase deficiency (PKD), where it was found to improve hemoglobin (Hb) concentrations in patients who did not regularly receive transfusions and to reduce transfusion burden in patients who receive regular transfusions. It was approved in 2022 for the treatment of PKD and is being explored in other hereditary chronic conditions that are associated with hemolytic mechanisms of anemia, such as sickle cell disease (SCD) and thalassemia. In a proof-of-concept phase I study in SCD, treatment with mitapivat demonstrated efficacy in increasing Hb concentrations, but also restored the thermostability of PKR, increasing its activity and decreasing 2,3-diphosphoglycerate (2,3-DPG) levels in sickle erythrocytes, which decreases Hb polymerization by increasing the affinity of Hb to oxygen. In thalassemia, mitapivat is hypothesized to increase adenosine triphosphate (ATP) production and mitigate harmful effects on red blood cells. This hypothesis is supported by preclinical data showing that mitapivat ameliorated ineffective erythropoiesis, iron overload and anemia in the Hbbth3/+ murine model of ß-thalassemia intermedia. The efficacy and safety of mitapivat were confirmed in an open-label, multicenter, phase II study of patients with non-transfusion-dependent α-thalassemia or ß-thalassemia, where activation of PKR improves anemia, and the drug showed a tolerable safety profile comparable to that in previous studies in other hemolytic anemias. Together, these efficacy and safety results provide rationale for continuing investigation of mitapivat for the treatment of thalassemia and SCD, developing other PK activators and starting investigational studies in other acquired diseases characterized by dyserythropoiesis and hemolytic anemia.

Iron-mediated tissue damage in acquired ineffective erythropoiesis disease: It's more a matter of burden or more of exposure to toxic iron form?

Iron is essential in cellular life, however, when in excess, it favors the production of reactive oxygen species (ROS) that, when overwhelm the physiological cellular antioxidant system, produce an oxidative stress state leading to cellular damages and organ failure. What is not yet completely clear is whether the damage is related more to the amount of iron or to the duration of exposure to ROS. Various cellular pathways are sensitive to the detrimental action of ROS in a non-dose-dependent manner. In addition, different organs have a different capacity to respond to iron-mediated toxicity, suggesting that the toxicity thresholds are disease-specific and patient-dependent. The aim of this article is to review the recent understanding of the concept of exposure to free iron-mediated damage, comprehending the need to design protocols in which reducing organ exposure to ROS is the primary objective in order to prevent or delay the development of organ damage.

Perls Stain Grade in Bone Marrow Aspirate Correlates with Overall Survival in Low-Risk Myelodysplastic Patients.

Low-risk patients with myelodysplastic syndromes (MDS) are inclined to long-term accumulation of iron in the organs due mostly to red blood cell transfusion and ineffective erythropoiesis. The effect of free toxic iron species in the liver and heart sites is well known, but recent knowledge assumes that oxidant-mediated tissue injury is also effective in the bone marrow. We aimed to investigate the predictive value of bone marrow iron accumulation as demonstrated by Perls staining on the overall survival (OS) of MDS patients. We retrospectively analyzed 114 low and intermediate-I IPSS risk MDS patients who were diagnosed at our institution in the last 20 years. The median age was 70 years (range 32-93). Two different experienced hematologists analyzed all samples. Perls Prussian blue stain was used to stain the bone marrow, which was assessed by modified Gale's grading and then correlated with the outcome. Twenty-seven patients had grade 1 (+), 31 grade 2 (++), and 56 grade 3 (+++). The 20-year OS was significantly lower in patients with a higher Perls score (6.8 ± 6.1%, median 80 ± 7 months in grade 3; 18.7 ± 9.4%, median 70 ± 17 months in grade 2; 33.2 ± 16.4%, median 144 ± 18 months in grade 1; p = 0.011); bone marrow iron overload (p = 0.003; HR 1.7) and transfusion dependency (0.001; HR 2.6) negatively impacted on survival. We suggest that a higher grade of iron storage at diagnosis can impact on the outcome in MDS patients. Perls stain, together with ferritin and the blood transfusional burden, could be another marker at diagnosis of iron-related toxicity that predicts survival.

Effects of different doses of erythropoietin in patients with myelodysplastic syndromes: A propensity score-matched analysis.

BACKGROUND: Erythropoiesis-stimulating agents effectively improve the hemoglobin levels in a fraction of anemic patients with myelodysplastic syndromes (MDS). Higher doses (HD) of recombinant human erythropoietin (rhEPO) have been proposed to overcome suboptimal response rates observed in MDS patients treated with lower "standard doses" (SD) of rhEPO. However, a direct comparison between the different doses of rhEPO is lacking. METHODS: A cohort of 104 MDS patients treated with HD was retrospectively compared to 208 patients treated with SD in a propensity score-matched analysis to evaluate hematological improvement-erythroid (HI-E) rate induced by the different doses of rhEPO. The impact of rhEPO doses on survival and progression to leukemia was also investigated. RESULTS: Overall HI-E rate was 52.6%. No difference was observed between different rhEPO doses (P = .28) in matched cohorts; in a subgroup analysis, transfusion-dependent patients and patients with higher IPSS-R score obtained a higher HI-E rate with HD, although without significant impact on overall survival (OS). Achievement of HI-E resulted in superior OS. At univariate analysis, a higher HI-E rate was observed in transfusion-independent patients (P < .001), with a lower IPSS-R score (P < .001) and lower serum EPO levels (P = .027). Multivariate analysis confirmed that rhEPO doses were not significantly related to HI-E (P = .26). There was no significant difference in OS or progression to leukemia in patients treated with HD vs SD. CONCLUSION: SD are substantially equally effective to HD to improve anemia and influencing survival in MDS patients stratified according to similar propensity to be exposed to rhEPO treatment.

Iron Toxicity and Hemopoietic Cell Transplantation: Time to Change the Paradigm.

The issue of iron overload in hemopoietic cell transplantation has been first discussed in the field of transplantation for thalassemia. Thalassemia major is characterized by ineffective erythropoiesis and hemolysis leading to severe anemia. Patients require regular blood transfusion therefore they develop iron overload causing organ damage and hematopoietic cell transplantation (HCT) is a consolidated reliably curative option. In this category of patients an important issue for transplant outcome is the iron burden before transplant and in the long-life post-transplant. Nevertheless today the concept of the impact of iron overload / toxicity on the outcome of HCT has been extended to other diseases characterized by periods of variable duration of transfusion dependence. Recent preclinical data has shown how increased production of reactive oxygen species (ROS) resulting under iron overload condition, could impair the stem cells clonality capacity, proliferation and maturation. Also, microenvironment cells could be affected through this mechanism. For this reason, iron overload is becoming an important issue also in the engraftment period post-transplant. The aim of this review is to update consolidated knowledge about the role of iron overload/iron toxicity in the HCT setting in non-malignant and in malignant diseases introducing the concept of exposition of free toxic iron forms and related cellular damage in the different stage of transplant.

Iron toxicity - Its effect on the bone marrow.

Excess iron can be extremely toxic for the body and may cause organ damage in the absence of iron chelation therapy. Preclinical studies on the role of free iron on bone marrow function have shown that iron toxicity leads to the accumulation of reactive oxygen species, affects the expression of genes coding for proteins that regulate hematopoiesis, and disrupts hematopoiesis. These effects could be partially attenuated by iron-chelation treatment with deferasirox, suggesting iron toxicity may have a negative impact on the hematopoietic microenvironment. Iron toxicity is of concern in transfusion-dependent patients. Importantly, iron chelation with deferasirox can cause the loss of transfusion dependency and may induce hematological responses, although the mechanisms through which deferasirox exerts this action are currently unknown. This review will focus on the possible mechanisms of toxicity of free iron at the bone marrow level and in the bone marrow microenvironment.

A storm in the niche: Iron, oxidative stress and haemopoiesis.

Iron, although essential, is harmful in high amounts. Oxidative stress as a result of excess reactive oxygen species (ROS) and a prooxidative/antioxidative imbalance between ROS production and elimination, play a key role in cellular damage. There is evidence to support the role of ROS in the pathogenesis of a range of diseases including the myelodysplastic syndromes (MDS) and leukaemia. Oxidative stress seems to affect the self-renewal, proliferation and differentiation of haematopoietic stem cells and impair cell growth. Three aspects of these defective haemopoietic mechanisms may be associated with the activities of ROS: clonal evolution, haematological improvement and recovery of haemopoiesis after haematopoietic stem cell transplantation (HSCT). This review aims to provide haematologists with an overview of results from in vitro and murine models and preliminary clinical evidence on the diagnostic, prognostic and therapeutic implications of the complex interactions between the haemopoietic niche, iron, oxidative stress and inadequate haemopoiesis.

Cardiogenic Shock during First Infusion of Anthracycline Chemotherapy in a Patient with Hodgkin Lymphoma: An Unusual Event.

INTRODUCTION: Hodgkin lymphoma (HL) is one of the most common types of cancers of the lymphatic system. The currently available therapies enable a cure in approximately 80-85% of treated patients. However, the cardiotoxicity of HL treatment has become a major cause of morbidity and mortality in survivors mainly related to the use of anthracycline. CASE REPORT: An HL, staged IIIB, was diagnosed in a 60-year-old man with no cardiovascular disease. During the first cycle of ABVD chemotherapy (Adriamycin; bleomycin; vinblastine; dacarbazine), near the end of the dacarbazine infusion, the patient presented a sudden cardiogenic shock characterized by a severe left ventricular systolic dysfunction. Laboratory and instrumental examinations performed did not suggest any specific etiology. After 15 days of medical support, the patient presented a complete cardiac function and clinical recovery. Subsequently bendamustine chemotherapy was started because of its limited extrahematological toxicity, but after 4 cycles the patient had progressive disease and died of septic shock. We concluded that a very rare hyperacute anthracycline cardiotoxicity was the most likely reason for this critical scenario. CONCLUSIONS: This rare event stresses our inability to correctly predict the risk of a patient developing cardiotoxicity and also highlights the need to improve the knowledge of underlying pathophysiological mechanisms; in fact, it suggests a possible genetic predisposition to develop cardiotoxicity due to a relatively limited dosage.

Myelodysplastic Syndromes and Iron Chelation Therapy.

Over recent decades we have been fortunate to witness the advent of new technologies and of an expanded knowledge and application of chelation therapies to the benefit of patients with iron overload. However, extrapolation of learnings from thalassemia to the myelodysplastic syndromes (MDS) has resulted in a fragmented and uncoordinated clinical evidence base. We're therefore forced to change our understanding of MDS, looking with other eyes to observational studies that inform us about the relationship between iron and tissue damage in these subjects. The available evidence suggests that iron accumulation is prognostically significant in MDS, but levels of accumulation historically associated with organ damage (based on data generated in the thalassemias) are infrequent. Emerging experimental data have provided some insight into this paradox, as our understanding of iron-induced tissue damage has evolved from a process of progressive bulking of organs through high-volumes iron deposition, to one of 'toxic' damage inflicted through multiple cellular pathways. Damage from iron may, therefore, occur prior to reaching reference thresholds, and similarly, chelation may be of benefit before overt iron overload is seen. In this review, we revisit the scientific and clinical evidence for iron overload in MDS to better characterize the iron overload phenotype in these patients, which differs from the classical transfusional and non-transfusional iron overload syndrome. We hope this will provide a conceptual framework to better understand the complex associations between anemia, iron and clinical outcomes, to accelerate progress in this area.

Management of iron overload before, during, and after hematopoietic stem cell transplantation for thalassemia major.

Solid evidence has established the negative impact of high iron burden and related tissue damage on the outcome of hemopoietic stem cell transplantation for thalassemia major. Recent improvements in our knowledge of iron metabolism have been focused on elevated non-transferrin-bound iron and labile plasma iron levels in the peritransplantation period as potential contributors to tissue toxicity and subsequent adverse transplant outcome. As mouse models have shown, iron overload can injure bone marrow hematopoiesis by increasing reactive oxygen species. The Pesaro experience, conducted in the deferoxamine-only era, clearly defined three iron-related factors (liver fibrosis, hepatomegaly, and quality of lifelong chelation) as significantly affecting transplant outcome. The detrimental effect of iron has only been clarified in recent years. Active interventional strategies are ongoing. Although successful hematopoietic stem cell transplantation clinically resolves the thalassemia marrow defect, patients still remain carriers of iron overload and of all the clinical complications acquired during prior years of transfusion therapy. Therefore, adequate "iron diagnosis" and management is mandatory after hemopoietic stem cell transplantation. In transplanted thalassemia patients, body iron should be returned to within the normal range. Phlebotomy is the gold standard to reduce iron burden; though deferoxamine is a proven, acceptable alternative, clinical investigations on deferasirox are ongoing.

The evolving clinical scenario of myelodysplastic syndrome: the need for a complete and up to date upfront diagnostic assessment.

Until the beginning of the current millennium, few concrete therapeutic possibilities were available for myelodysplastic syndrome (MDS) patients. This situation has dramatically changed in the last decade when new knowledge, new drugs and new opportunities have become available for physicians and their MDS patients. A correct diagnostic and prognostic assessment of all MDS patients wherever they are first seen in a hematology or internal medicine department is mandatory to identify the best therapeutic option and the most appropriate resources allocation. This article will review modern diagnostic criteria and classification together with correlated new therapeutic opportunities.

Hematopietic stem cell transplantation in thalassemia and related disorders.

The basis of allogeneic hemopoietic stem cell (HSC) transplantation in thalassemia consists in substituting the ineffective thalassemic erythropoiesis with and allogeneic effective one. This cellular replacement therapy is an efficient way to obtain a long lasting, probably permanent, clinical effective correction of the anaemia avoiding transfusion requirement and subsequent complications like iron overload. The first HSC transplant for thalassemia was performed in Seattle on Dec 2, 1981. In the early eighties transplantation procedure was limited to very few centres worldwide. Between 17 December 1981 and 31 January 2003, over 1000 consecutive patients, aged from 1 to 35 years, underwent transplantation in Pesaro. After the pioneering work by the Seattle and Pesaro groups, this therapeutic approach is now widely applied worldwide. Medical therapy of thalassemia is one of the most spectacular successes of the medical practice in the last decades. In recent years advances in knowledge of iron overload patho-physiopathology, improvement and diffusion of diagnostic capability together with the development of new effective and safe oral chelators promise to further increase success of medical therapy. Nevertheless situation is dramatically different in non-industrialized countries were the very large majority of patients live today. Transplantation technologies have improved substantially during the last years and transplantation outcome is likely to be much better today than in the '80s. Recent data indicated a probability of overall survival and thalassemia free survival of 97% and 89% for patients with no advanced disease and of 87% and 80% for patients with advanced disease. Thus the central role of HSC in thalassemia has now been fully established. HSC remains the only definitive curative therapy for thalassemia and other hemoblobinopathies. The development of oral chelators has not changed this position. However this has not settled the controversy on how this curative but potentially lethal treatment stands in front of medical therapy for adults and advanced disease patients. In sickle cell disease HSC transplantation currently is reserved almost exclusively for patients with clinical features that indicate a poor outcome or significant sickle-related morbidity.

Treosulfan/fludarabine as an allogeneic hematopoietic stem cell transplant conditioning regimen for high-risk patients.

In recent years, new conditioning regimens have been explored in patients not eligible for conventional transplant with the aim to reduce transplant-related mortality. In a phase II multicentric prospective trial, we investigated the safety and feasibility of the treosulfan-fludarabine combination prior to allogeneic hematopoietic stem cell transplant in patients with various hematological malignancies not eligible for conventional regimens because of previous intensive treatment, older age, and comorbidities. Forty-six consecutive patients, median age 48 years (range 17-69), were enrolled. Sixteen of them were in complete remission, and 20 had a HSCT comorbidity index > or = 1. Forty-four patients had regular and sustained engraftment, and 39 out of 40 evaluable patients developed complete chimerism. Nonhematological toxicity was limited. Risk of transplant-related mortality was 9% (95% CI, 2-17%) at day +100 and plotted at 15% (95% CI, 7-22%) after 7 months. The estimated overall survival and progression-free survival with a median follow-up of 20 months were 51% and 38%, respectively. The estimated 30 months progression-free survival for patients transplanted in remission was 56%. The treosulfan-fludarabine combination is a reduced-toxicity but myeloablative regimen that can be proposed to patients not fitting criteria for conventional transplant regimens. Longer follow-up and further prospective studies are necessary to evaluate this regimen.