Search

Summary Hydroxycarbamide (HC) is the most widely used therapeutic for individuals with sickle cell disease (SCD, including sickle cell anemia and other forms of the disease). HC's clinical benefits are primarily associated with its ability to induce foetal haemoglobin (HbF); this limited view of HC's therapeutic potential may lead to its discontinuation when a modest amount of HbF is induced. A better understanding of the HbF‐independent effects of HC on genes and pathways relevant to SCD pathophysiology is therefore needed. In this study, we performed bulk RNA‐Seq on whole blood samples collected from a cohort of 25 paediatric patients with SCD to identify genes and pathways that are affected by treatment with HC. At the maximum tolerated dose (MTD) of HC, patients showed altered expression levels of several genes and biological pathways. Pathways related to haeme metabolism, interferon‐alpha response, and interferon‐gamma response were significantly downregulated at HC MTD relative to the matched pre‐HC samples. Pathways linked with IL2‐STAT5 signalling and TNFα signalling via NF‐Kβ were observed to be up‐regulated at HC MTD. These results illustrate the range of effects exerted by HC during therapy for SCD and pave the way for an improved understanding of the HbF induction‐independent benefits of HC. [ABSTRACT FROM AUTHOR]

Sickle cell disease (SCD) is the most common monogenic disorder in Saudi Arabia, which associates with an increased risk of organs damage, including the kidney. The aim of this study is to investigate the prevalence and predictors of sickle cell nephropathy (SCN) in the Saudi population. A retrospective study was conducted from April to October 2023, and included 343 adult patients with SCD who were recruited from the hereditary blood diseases center (HBDC), Al-Ahsa, Saudi Arabia. Spot protein-to-creatinine ratio was measured and glomerular filtration rate (GFR) was estimated from serum creatinine using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. As per KIDGO guidelines, CKD was diagnosed in 93 (27.1%) patients. Based on the CKD-EPI equation, 2% of patients had low GFR (eGFR < 60mL/min), 28.3% had high GFR (eGFR > 140 mL/min), and 69.7% had normal GFR. Among SCD patients, proteinuria was observed in 26.5% of the patients. SCD patients with CKD were significantly older than non-CKD patients (p < 0.001) and had higher prevalence of diabetes mellitus (DM) and hypertension (HTN) (p = 0.045 and 0.001 respectively). The multivariate analysis showed that age (P = 0.001; OR 1.035; 95% CI 1.014–1.056) and low hemoglobin level (p = 0.034; OR -0.851; 95% CI 0.721–0.980) were independent risk factors for the development of SCN. Nephropathy is a common complication among patients with SCD as early as the third decade of life, although they remain asymptomatic. Advances in age and low hemoglobin levels are the main predictors of nephropathy. In addition, SCD patients with coexistent comorbidities, particularly DM and HTN, were at increased risk of developing kidney disease. [ABSTRACT FROM AUTHOR]

Despite advancements in treatment of sickle cell disease (SCD), hydroxyurea, a ribonucleotide reductase inhibitor, remains the cornerstone of therapy. While its primary effect is the elevation of fetal hemoglobin (HbF), hydroxyurea's mechanisms of action are multifaceted. Hydroxyurea (HU) reduces leukocyte and platelet counts, decreases the expression of endothelial adhesion molecules CD36 and CD49d, and increases nitric oxide and cyclic nucleotide levels, which may facilitate vascular dilation and further HbF induction. Numerous studies have demonstrated that hydroxyurea therapy reduces the frequency of painful episodes, acute chest syndrome, and the need for erythrocyte transfusions and hospitalizations. Long-term use of hydroxyurea leads to reduced morbidity and mortality. Hydroxyurea should be initiated in children from 9 months of age, including asymptomatic individuals, and is recommended for adults experiencing pain crises that significantly interfere with daily activities or quality of life, as well as those with severe or recurrent vaso-occlusive crises, ACS, or severe symptomatic anemia. Hydroxyurea is not recommended during pregnancy or lactation due to potential teratogenic effects and transfer into breast milk. However, its use may be considered in high-risk patients, particularly during the second and third trimesters. Concerns about secondary tumor development have not been substantiated in long-term follow-up studies. Alternative therapies, including L-glutamine, crizanlizumab, and voxelotor, are not presently approved or available for clinical use in Europe. [ABSTRACT FROM AUTHOR]

Ruxolitinib, a JAK1/JAK2 inhibitor, has been shown to have lower thromboembolism rates compared to placebo in polycythemia vera (PV) patients. This meta‐analysis evaluates ruxolitinib's efficacy and safety against best available therapy (BAT) in patients with PV and in hydroxyurea‐resistant/intolerant PV patients. A comprehensive literature search was conducted up to November 2023. We compared ruxolitinib and BAT for efficacy and safety endpoints. Six studies involving 1061 patients were analyzed, with 620 on BAT and 441 on ruxolitinib. Ruxolitinib showed higher hematocrit control (p = 0.015) and treatment response (p = 0.04) compared to BAT. It also significantly improved Myeloproliferative Neoplasms‐Symptom Assessment Form scores (MPN‐SAF) (p < 0.01). Additionally, patients with PV treated with ruxolitinib had higher rates of nonmelanoma skin cancer (p < 0.01). In subgroup analyses focusing on patients resistant or intolerant to hydroxyurea, ruxolitinib maintained its efficacy, significantly improving treatment response (p < 0.01) and significant improvements in MPN‐SAF (p = 0.02) score when compared to BAT. The safety profile was consistent with the overall analyses, showing significantly reduced thromboembolism rates (p = 0.04), increased rates of anemia (p = 0.01), and increased herpes zoster infections (p = 0.02). Ruxolitinib outperforms BAT in PV and patients with PV‐resistant or intolerant to hydroxyurea, offering better hematocrit control and reducing symptomatic burden and thromboembolism risk. Yet, it is associated with higher rates of anemia, herpes infection, and skin cancer. [ABSTRACT FROM AUTHOR]

Hydroxyurea is an antimetabolite that inhibits DNA synthesis and is used as a treatment option in chronic myeloproliferative disorders. Rarely, "dermatomyositis (DM)‐like" skin lesions are observed after long‐term therapy. In this case series, five skin biopsies of four patients were evaluated by histology, immunohistochemistry, and next‐generation sequencing of the TP53 gene locus. All biopsies showed focal basal pleomorphic keratinocytes and suprabasal aberrant p53 expression as well as sparse to severe vacuolar interface dermatitis. Histopathologically, "DM‐like" skin lesions can be clearly distinguished from DM by marked subepidermal fibrosis, vascular proliferation, and the absence of dermal mucin deposits. In 75% of the specimens multiple, partly inactivating and/or pathogenic point mutations of TP53 were found in low frequencies. "DM‐like" skin eruptions as a long‐term consequence of hydroxyurea therapy are possibly not chemotherapy‐associated benign toxic changes, but rather inflammatory reactions to complex keratinocyte alterations that clinically mimic the picture of DM. Synergistic mutagenic effects of hydroxyurea and sunlight might be responsible for this unique drug side effect and could provide a pathogenic link to the known increased risk of skin cancer in these patients. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Methods Results Conclusions Access to crizanlizumab, a disease‐modifying therapy for sickle cell disease (SCD), was provided through a managed access program (MAP, NCT03720626). The present analysis evaluated the impact of 12 months of crizanlizumab treatment on vaso‐occlusive crises (VOCs), and on the use of opioids for VOC‐related pain relief, in patients with SCD from the MAP.From June 2018 to January 2023, 112 patients with a history of recurrent VOCs completed 12 months of crizanlizumab (5 mg/kg) treatment and were monitored for adverse events (AEs).Crizanlizumab led to reductions of 18.0% and 36.2% in the proportions of patients having ≥ 1 home‐ and ≥ 1 healthcare‐managed VOCs. Median absolute changes (interquartile range) from baseline in the rates of home‐ and healthcare‐managed VOCs were −3.0 (−6.0, −1.0) and −2.0 (−4.0, 0), respectively. Data stratified by genotype and prior hydroxyurea use showed similar reductions in VOC rates. A 35.5% reduction in the proportion of patients requiring opioids was noted. AEs were consistent with earlier reports, and no new safety concerns were identified.Crizanlizumab demonstrated potential benefits in attenuating VOC episodes, irrespective of SCD genotype and prior hydroxyurea use, and in lowering opioid usage. The safety of crizanlizumab was consistent with earlier reports.Trial Registration: The MAP has been registered at ClinicalTrials.gov with the ID, NCT03720626 [ABSTRACT FROM AUTHOR]

Background and Objectives: Hydroxyurea (HU) is an effective medication used to reduce the frequency of painful crises associated with sickle cell disease (SCD). However, data describing its prevalence among SCD patients in the Eastern Region of Saudi Arabia are scarce. This is a multi-center, retrospective, cross-sectional study that aims to investigate the pattern of prescribing HU in SCD patients and to determine the association between prescribing HU and other co-prescribed medications used to manage SCD complications. Methods: Data were collected from patients who visited the hematology clinics of Al-Qatif Central Hospital (QCH) and King Fahad Hospital in Hofuf (KFHH) between June 2021 to May 2023. The data included demographics, prescribed medications, and recent laboratory test results, all of which were collected from patients' medical records. Descriptive statistics were utilized to assess the difference between HU users vs. non-users. A binary logistic regression model was used to determine the association between prescribing HU and co-prescribed medications used to manage SCD complications. The results are presented as the odds ratio (OR) and 95% confidence interval (95% CI). Results: This study included 2816 SCD patients with a 56% prevalence of HU prescription. HU was prescribed for young age groups more often compared to old age group patients. Young males were more likely to be prescribed with HU compared to females, and it becomes dominant in females after the age of 36. HU users were more likely to have paracetamol (69% vs. 53%, OR = 1.9, 95% CI 1.6–2.2), NSAIDs (50% vs. 35%, OR = 1.7, 95% CI 1.5–2), and opioids (41% vs. 37%, OR = 1.3, 95% CI 1.1–1.6) co-prescribed, and less often to have laxatives (8% vs. 5%, OR = 0.66, 95% CI 0.48–0.9) and anticoagulants (22% vs. 15%, OR = 0.56, 95% CI 0.46–0.68) co-prescribed compared to non-users. Conclusions: The pattern of prescribing HU, supported by the association findings, raises concerns about patients' compliance and adherence to HU therapy. Early health education, specifically to young female SCD patients, is warranted to increase the success rate of HU therapy. [ABSTRACT FROM AUTHOR]

Summary HbSC disease is a common form of sickle cell disease with significant morbidity and early mortality. Whether hydroxyurea is beneficial for HbSC disease is unknown. Prospective Identification of Variables as Outcomes for Treatment (PIVOT, Trial ID PACTR202108893981080) is a double‐blind, randomised, placebo‐controlled phase II trial of hydroxyurea for people with HbSC, age 5–50 years, in Ghana. After screening, participants were randomised to placebo (standard of care) or hydroxyurea. The primary outcome is the cumulative incidence of haematological toxicities during 12 months of blinded treatment; secondary outcomes include multiple laboratory and clinical assessments. Between April 2022 and June 2023, 112 children and 102 adults were randomised, including 44% females and average age 21.6 ± 14.5 years. Participants had substantial morbidity including previous hospitalisations (93%), vaso‐occlusive events (86%), malaria (79%), often received transfusions (20%), with baseline haemoglobin 11.0 ± 1.2 g/dL and foetal haemoglobin 1.8% ± 1.5%. The spleen was palpable in six children and one adult, and ultrasonographic volumes were collected. Proliferative sickle retinopathy was common (30% children, 75% adults), but proteinuria was less common (3% children, 8% adults). Whole blood viscosity, ektacytometry, point‐of‐sickling, transcranial Doppler, near‐infrared spectrometry (NIRS), 6‐minute walk, and quality of life were also measured. Now fully enrolled, PIVOT will document the safety and potential benefits of hydroxyurea on clinical and laboratory outcomes in HbSC disease. [ABSTRACT FROM AUTHOR]

Background: Sickle cell disease (SCD) is among the most frequent hereditary disorders globally and its prevalence in Europe is increasing due to migration movements. Summary: The basic pathophysiological event of SCD is polymerization of deoxygenated sickle hemoglobin, resulting in hemolysis, vasoocclusion, and multiorgan damage. While the pathophysiological cascade offers numerous targets for treatment, currently only two disease-modifying drugs have been approved in Europe and transfusion remains a mainstay of both preventing and treating severe complications of SCD. Allogeneic stem cell transplantation and gene therapy offer a curative option but are restricted to few patients due to costs and limited availability of donors. Key Message: Further efforts are needed to grant patients access to approved treatments, to explore drug combinations and to establish new treatment options. [ABSTRACT FROM AUTHOR]

Hydroxyurea (HU) is the most common drug therapy for sickle cell disease (SCD). The clinical benefits of HU derive from its upregulation of fetal hemoglobin (HbF), which reduces aggregation of the mutated sickle hemoglobin protein (HbS) and reduces SCD symptoms and complications. However, some individuals do not respond to HU, or stop responding over time. Unfortunately, current understanding of the mechanism of action of HU is limited, hindering the ability of clinicians to identify those patients who will respond to HU and to optimize treatment for those receiving HU. Given that epigenetic modifications are essential to erythropoiesis and HbF expression, we hypothesize that some effects of HU may be mediated by epigenetic modifications, specifically DNA methylation. However, few studies have investigated this possibility and the effects of HU on DNA methylation remain relatively understudied. In this review, we discuss the evidence linking HU treatment to DNA methylation changes and associated gene expression changes, with an emphasis on studies that were performed in individuals with SCD. Overall, although HU can affect DNA methylation, research on these changes and their clinical effects remains limited. Further study is likely to contribute to our understanding of hematopoiesis and benefit patients suffering from SCD. [ABSTRACT FROM AUTHOR]