Polycythemia vera (PV) and essential thrombocythemia (ET) are myeloproliferative neoplasms characterized by increased rate of cardiovascular events, a varying burden of symptoms, and an intrinsic ...risk of evolution to secondary forms of myelofibrosis and acute leukemia; however, survival is only modestly reduced in most instances. In the last few years, following the description of driver mutations in JAK2, MPL and CALR, the diagnostic criteria for PV and ET were revised, making the identification of very early stages feasible. Scores for identifying patients at different risk of thrombosis were refined, and they largely guide therapeutic decisions. Treatment is therefore mainly focused on reduction of thrombosis risk, control of myeloproliferation, improvement of symptomatic burden, and management of disease-associated complications. New drugs recently entered the clinical arena, with the promise to improve overall patients' management. However, evidence of a disease-modifying potential is largely missing and represents a still unmet clinical need.
There has been a major revolution in the management of patients with myeloproliferative neoplasms (MPN), and in particular those with myelofibrosis and extensive splenomegaly and symptomatic burden, ...after the introduction of the JAK1 and JAK2 inhibitor ruxolitinib. The drug also has been approved as second-line therapy for polycythemia vera (PV). However, the therapeutic armamentarium for MPN is still largely inadequate for coping with patients' major unmet needs, which include normalization of life span (myelofibrosis and some patients with PV), reduction of cardiovascular complications (mainly PV and essential thrombocythemia), prevention of hematological progression, and improved quality of life (all MPN). In fact, none of the available drugs has shown clear evidence of disease-modifying activity, even if some patients treated with interferon and ruxolitinib showed reduction of mutated allele burden, and ruxolitinib might extend survival of patients with higher-risk myelofibrosis. Raised awareness of the molecular abnormalities and cellular pathways involved in the pathogenesis of MPN is facilitating the development of clinical trials with novel target drugs, either alone or in combination with ruxolitinib. Although for most of these molecules a convincing preclinical rationale was provided, the results of early phase 1 and 2 clinical trials have been quite disappointing to date, and toxicities sometimes have been limiting. In this review, we critically illustrate the current landscape of novel therapies that are under evaluation for patients with MPN on the basis of current guidelines, patient risk stratification criteria, and previous experience, looking ahead to the chance of a cure for these disorders.
As the second leading cause of death and disability worldwide, stroke is mainly caused by atherosclerosis and cardiac embolism, particularly in older individuals. Nevertheless, in young and otherwise ...healthy individuals, the causes of stroke can be more diverse and may include conditions such as patent foramen ovale, vasculitis, coagulopathies, genetic factors, or other undetermined causes. Although these other causes of stroke account for a relatively small proportion compared to ischemic stroke, they are becoming increasingly common in clinical practice and deserve attention. Here, we present a rare female patient with polycythemia vera (PV) who was admitted to the hospital as a stroke patient without any previous medical history.
A 40-year-old young woman felt sudden dizziness and slow response. After 4 days of being admitted, she developed blurry vision on the right.
Cranial magnetic resonance imaging revealed aberrant signals in the left temporal and parietal lobe, as well as multiple small focal signal abnormalities were observed in the left frontal lobe. Magnetic resonance angiography revealed partial stenosis of the left internal carotid artery. The patient's blood routine examination revealed a significant elevation in complete blood counts, particularly the increase in red blood cells, as well as prolonged clotting time. An abdominal ultrasound and abdomen computed tomography showed splenomegaly. The outcome of the genetic testing was positive for the Janus kinase JAK2 exon V617F mutation (JAK2/V617F). The patient was diagnosed with PV-related stroke.
The patient was treated with phlebotomy, cytoreductive therapy, and low-dose aspirin antiplatelet therapy and was regularly followed up in hematology and neurology clinics after discharge.
The patient's red blood cell, leukocyte, and thrombocyte counts had fully normalized, with her hemoglobin level measuring at 146 g/L and hematocrit value at 43%. Furthermore, there had been a significant improvement in neurological symptoms.
PV, a rare hematological disorder, can present with ischemic stroke as the initial performance, and the diagnosis mainly relies on routine blood tests, bone marrow biopsies, and genetic test. Therefore, clinicians should pay attention to PV, a low-prevalence disease, when encountering stroke in youth.
The Food and Drug Administration approval of ruxolitinib for treatment of myelofibrosis and polycythemia vera has changed the management of patients with myeloproliferative neoplasms. Yet the impact ...of this therapy on risk of thrombosis, a major cause of morbidity and mortality among these patients, remains unknown. The aim of this study was to evaluate the impact of ruxolitinib on the risk of thrombosis among patients with polycythemia vera or myelofibrosis. Following identification of randomized controlled trials comparing ruxolitinib to standard care or placebo, rates of thrombosis, including venous and arterial thrombosis, were analyzed using fixed effects models. Rates of thrombosis were significantly lower among patients treated with ruxolitinib risk ratio 0.45, 95% confidence interval (CI) 0.23-0.88. Subgroup analysis of venous and arterial thrombosis demonstrated similar risk ratios, which did not reach statistical significance (risk ratio 0.46, 95% CI 0.14-1.48 and RR 0.42, 95% CI 0.18-1.01, respectively). In conclusion, our analysis suggests that JAK2 inhibition with ruxolitinib decreases the risk of arterial and/or venous thrombosis in patients with polycythemia vera or myelofibrosis. These findings will require confirmation in a prospective study.
Despite its popularity along with many proposed therapeutic applications, the safety profile of Aloe vera gel beverages remains unsettled. The putative toxicology concern has focused on the ...hydroxyanthraquinone derivatives (HADs) found in the latex portion of the Aloe leaf. Despite harvesting and processing designed to eliminate or significantly reduce these compounds, certain HADs, such as aloin, may be present and have been associated with carcinogenicity in non-decolorized whole leaf extract containing approximately 6400 ppm aloin A and 71 ppm aloin-emodin. Sprague Dawley rats had free access to drinking water or a commercially and widely available Aloe vera gel beverage (Forever Living Products) prepared from the inner leaves of Aloe barbadensis Miller containing 3.43 ppm total aloin for 90 days. Under the conditions of the study and based on the toxicological endpoints evaluated, there were no adverse test substance-related findings, including altered thyroid hormones. No histologic differences or histopathological changes were detected in the multiple tissues and organs examined. The Ki-67 proliferation assay demonstrated no increased cell proliferation in the liver, lungs, kidneys, or urinary bladder, which might have been attributed to the dietary administration of the Aloe vera gel beverage via drinking water for 90 days. These data lend increasing confidence regarding the safety of appropriately processed Aloe vera gel beverages, such as the beverage tested in this study.
Hepcidin agonists are a new class of compounds that regulate blood iron levels, limit iron absorption, and could improve the treatment of hemochromatosis, β-thalassemia, polycythemia vera, and other ...disorders in which disrupted iron homeostasis causes or contributes to disease. Hepcidin agonists also have the potential to prevent severe complications of siderophilic infections in patients with iron overload or chronic liver disease. This review highlights the preclinical studies that support the development of hepcidin agonists for the treatment of these disorders.
Polycythemia vera is a chronic myeloproliferative neoplasm characterized by erythrocytosis. Rusfertide, an injectable peptide mimetic of the master iron regulatory hormone hepcidin, restricts the ...availability of iron for erythropoiesis. The safety and efficacy of rusfertide in patients with phlebotomy-dependent polycythemia vera are unknown.
In part 1 of the international, phase 2 REVIVE trial, we enrolled patients in a 28-week dose-finding assessment of rusfertide. Part 2 was a double-blind, randomized withdrawal period in which we assigned patients, in a 1:1 ratio, to receive rusfertide or placebo for 12 weeks. The primary efficacy end point was a response, defined by hematocrit control, absence of phlebotomy, and completion of the trial regimen during part 2. Patient-reported outcomes were assessed by means of the modified Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF) patient diary (scores range from 0 to 10, with higher scores indicating greater severity of symptoms).
Seventy patients were enrolled in part 1 of the trial, and 59 were assigned to receive rusfertide (30 patients) or placebo (29 patients) in part 2. The estimated mean (±SD) number of phlebotomies per year was 8.7±2.9 during the 28 weeks before the first dose of rusfertide and 0.6±1.0 during part 1 (estimated difference, 8.1 phlebotomies per year). The mean maximum hematocrit was 44.5±2.2% during part 1 as compared with 50.0±5.8% during the 28 weeks before the first dose of rusfertide. During part 2, a response was observed in 60% of the patients who received rusfertide as compared with 17% of those who received placebo (P = 0.002). Between baseline and the end of part 1, rusfertide treatment was associated with a decrease in individual symptom scores on the MPN-SAF in patients with moderate or severe symptoms at baseline. During parts 1 and 2, grade 3 adverse events occurred in 13% of the patients, and none of the patients had a grade 4 or 5 event. Injection-site reactions of grade 1 or 2 in severity were common.
In patients with polycythemia vera, rusfertide treatment was associated with a mean hematocrit of less than 45% during the 28-week dose-finding period, and the percentage of patients with a response during the 12-week randomized withdrawal period was greater with rusfertide than with placebo. (Funded by Protagonist Therapeutics; REVIVE ClinicalTrials.gov number, NCT04057040.).
In polycythemia vera, vascular risk assessment is based on age and thrombotic history, while the role of other potential predictors of this risk is still uncertain. Thus, we exploited the large ...database collected by the observational study of the European Collaboration on Low-Dose Aspirin in Polycythemia Vera (ECLAP) to investigate the association of hematologic variables and cardiovascular risk factors with the thrombotic risk. Among 1638 polycythemic patients followed for 2.7 ± 1.3 years, there were 205 thromboses. Subjects with hypertension had a mild nonsignificant increase in the risk of arterial thrombosis, while this risk was significantly increased by smoking (hazard ratio HR, 1.90; 95% confidence interval CI, 1.15-3.14; P = .012). The time-dependent analysis adjusted for potential confounders showed that patients with a white blood cell count above 15 × 109/L, compared with those with a white blood cell count below 10 × 109/L, had a significant increase in the risk of thrombosis (HR, 1.71; 95% CI, 1.10-2.65; P = .017), mainly deriving from an increased risk of myocardial infarction (HR, 2.84; 95% CI, 1.25-6.46; P = .013). Thus, leukocyte count may help in defining the vascular risk of polycythemic subjects.
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