Comparative efficacy and safety of deferoxamine, deferiprone and deferasirox on severe thalassemia: a meta-analysis of 16 randomized controlled trials

Calcium channel blockers for preventing cardiomyopathy due to iron overload in people with transfusion-dependent beta thalassaemia

BACKGROUND

Beta-thalassaemia is an inherited blood disorder that reduces the production of haemoglobin. The most severe form requires recurrent blood transfusions, which can lead to iron overload. Cardiovascular dysfunction caused by iron overload is the leading cause of morbidity and mortality in people with transfusion-dependent beta-thalassaemia. Iron chelation therapy has reduced the severity of systemic iron overload, but removal of iron from the myocardium requires a very proactive preventive strategy. There is evidence that calcium channel blockers may reduce myocardial iron deposition. This is an update of a Cochrane Review first published in 2018.

OBJECTIVES

To assess the effects of calcium channel blockers plus standard iron chelation therapy, compared with standard iron chelation therapy (alone or with a placebo), on cardiomyopathy due to iron overload in people with transfusion-dependent beta thalassaemia.

SEARCH METHODS

We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books, to 13 January 2022. We also searched ongoing trials databases and the reference lists of relevant articles and reviews.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of calcium channel blockers combined with standard chelation therapy versus standard chelation therapy alone or combined with placebo in people with transfusion-dependent beta thalassaemia.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We used GRADE to assess certainty of evidence.

MAIN RESULTS

We included six RCTs (five parallel-group trials and one cross-over trial) with 253 participants; there were 126 participants in the amlodipine arms and 127 in the control arms. The certainty of the evidence was low for most outcomes at 12 months; the evidence for liver iron concentration was of moderate certainty, and the evidence for adverse events was of very low certainty. Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may have little or no effect on cardiac T2* values at 12 months (mean difference (MD) 1.30 ms, 95% confidence interval (CI) -0.53 to 3.14; 4 trials, 191 participants; low-certainty evidence) and left ventricular ejection fraction (LVEF) at 12 months (MD 0.81%, 95% CI -0.92% to 2.54%; 3 trials, 136 participants; low-certainty evidence). Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may reduce myocardial iron concentration (MIC) after 12 months (MD -0.27 mg/g, 95% CI -0.46 to -0.08; 3 trials, 138 participants; low-certainty evidence). The results of our analysis suggest that amlodipine has little or no effect on heart T2*, MIC, or LVEF after six months, but the evidence is very uncertain. Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may increase liver T2* values after 12 months (MD 1.48 ms, 95% CI 0.27 to 2.69; 3 trials, 127 participants; low-certainty evidence), but may have little or no effect on serum ferritin at 12 months (MD 0.07 μg/mL, 95% CI -0.20 to 0.35; 4 trials, 187 participants; low-certainty evidence), and probably has little or no effect on liver iron concentration (LIC) after 12 months (MD -0.86 mg/g, 95% CI -4.39 to 2.66; 2 trials, 123 participants; moderate-certainty evidence). The results of our analysis suggest that amlodipine has little or no effect on serum ferritin, liver T2* values, or LIC after six months, but the evidence is very uncertain. The included trials did not report any serious adverse events at six or 12 months of intervention. The studies did report mild adverse effects such as oedema, dizziness, mild cutaneous allergy, joint swelling, and mild gastrointestinal symptoms. Amlodipine may be associated with a higher risk of oedema (risk ratio (RR) 5.54, 95% CI 1.24 to 24.76; 4 trials, 167 participants; very low-certainty evidence). We found no difference between the groups in the occurrence of other adverse events, but the evidence was very uncertain. No trials reported mortality, cardiac function assessments other than echocardiographic estimation of LVEF, electrocardiographic abnormalities, quality of life, compliance with treatment, or cost of interventions.

AUTHORS' CONCLUSIONS

The available evidence suggests that calcium channel blockers may reduce MIC and may increase liver T2* values in people with transfusion-dependent beta thalassaemia. Longer-term multicentre RCTs are needed to assess the efficacy and safety of calcium channel blockers for myocardial iron overload, especially in younger children. Future trials should also investigate the role of baseline MIC in the response to calcium channel blockers, and include a cost-effectiveness analysis.

Grape seed extract in combination with deferasirox ameliorates iron overload, oxidative stress, inflammation, and liver dysfunction in beta thalassemia children

BACKGROUND AND PURPOSE

Iron overload in the body is associated with serious and irreversible tissue damage. This study aimed to investigate the iron-chelating, antioxidant, anti-inflammatory, and hepatoprotective activities of grape seed extract (GSE) supplement as well as its safety in β-thalassemia major (β-TM) pediatric patients receiving deferasirox as a standard iron-chelation therapy.

MATERIALS AND METHODS

The children were randomly allocated to either GSE group (n = 30) or control group (n = 30) to receive GSE (100 mg/day) or placebo capsules, respectively, for 4 weeks. The serum levels of iron, ferritin, total iron-binding capacity (TIBC), alanine transaminase (ALT), aspartate aminotransferase (AST), tumor necrosis factor alpha (TNF-α), high-sensitivity C-reactive protein (hs-CRP), malondialdehyde (MDA), and glutathione (GSH) as well as superoxide dismutase (SOD) activity and hemoglobin (Hb) concentration were measured pre-and post-intervention.

RESULTS

GSE supplement significantly attenuated the serum levels of iron (p = 0.030), ferritin (p = 0.017), ALT (p = 0.000), AST (p = 0.000), TNF-α (p = 0.000), and hs-CRP (p = 0.001). The TIBC level (p = 0.020) significantly enhanced in the GSE group compared with the placebo group. Moreover, GSE supplement remarkably improved the oxidative stress markers, MDA (p = 0.000) and GSH (p = 0.001). The changes in the SOD activity (p = 0.590) and Hb concentration (p = 0.670) were not statistically different between the groups.

CONCLUSION

GSE supplement possesses several health beneficial influences on children with β-TM by alleviating iron burden, oxidative stress, inflammation, and liver dysfunction.

Prevalence and Management of Transfusional Iron Overload in Syrian Beta Thalassemia Major Patients Pre and during the Syrian Conflict

Objectives

The primary aim of this study was to evaluate the prevalence of iron overload and the real-world clinical effectiveness of the iron chelation therapies (ICTs) in Syrian patients with transfusion-dependent beta thalassemia major (BTM) prior to and during the ongoing Syrian conflict.

Methods

This single-center, two-stage observational study was conducted at Homs National Thalassemia Center (HNTC) prior to (2009) and during (2019) the armed conflict. The prevalence and the severity of iron overload, as well as the effectiveness of four iron chelation regimens, were assessed using serum ferritin (SF) concentrations as a means of monitoring in two cohorts of BTM patients receiving deferoxamine (DFO), deferiprone (DFP), deferasirox (DFX), or a combination of DFO and DFP therapy in both years. Statistical analyses encompassed one-way ANOVA, Kruskal-Wallis, Mann-Whitney U, and chi-square (χ2) tests for the comparisons of the variables and the frequencies between the two cohorts and subgroups.

Results

We included all eligible BTM patients at HNTC in 2009 (n = 205) and 2019 (n = 172). Only 84 patients from the 2009 cohort were accessible in 2019. Our findings revealed that 98% and 89% of the patients had iron overload (SF ≥ 1500 ng/mL) and comparable elevated median SF concentrations (3868 and 3757 ng/mL) in 2009 and 2019, respectively (P = 0.275). Furthermore, patients on DFO demonstrated the poorest control of iron overload and the highest SF concentrations (4319 and 5586 ng/mL), whereas those on DFX achieved superior outcomes and the lowest SF concentrations (3355 and 2152 ng/mL) in both years. Twenty-six patients from the 2019 cohort received no ICT for six years (from 2012 to 2018) and experienced extremely severe iron overload with SF levels ranging between 4481 and 16,000 ng/mL.

Conclusions

Our findings prove a high prevalence of iron overload and suboptimal chelation outcomes in Syrian BTM patients, both prior to and during the ongoing armed conflict, despite the provision of free ICTs at HNTC. Poor adherence and older age of patients may explain the unfavorable outcomes of DFO and (DFO+DFP) regimens, whereas younger age and higher socioeconomic status may have contributed to the lowest SF and superior outcomes in patients on DFX. This study also demonstrates the crucial role of the National Thalassemia Centers, namely HNTC, in providing health services to BTM patients in times of peace and conflict.

The iron chelator deferriferrichrysin induces paraptosis via extracellular signal-related kinase activation in cancer cells

Cancer cells generally exhibit increased iron uptake, which contributes to their abnormal growth and metastatic ability. Iron chelators have thus recently attracted attention as potential anticancer agents. Here, we show that deferriferrichrysin (Dfcy), a natural product from Aspergillus oryzae acts as an iron chelator to induce paraptosis (a programmed cell death pathway characterized by ER dilation) in MCF-7 human breast cancer cells and H1299 human lung cancer cells. We first examined the anticancer efficacy of Dfcy in cancer cells and found that Dfcy induced ER dilation and reduced the number of viable cells. Extracellular signal-related kinase (ERK) was activated by Dfcy treatment, and the MEK inhibitor U0126, a small molecule commonly used to inhibit ERK activity, prevented the increase in ER dilation in Dfcy-treated cells. Concomitantly, the decrease in the number of viable cells upon treatment with Dfcy was attenuated by U0126. Taken together, these results demonstrate that the iron chelator Dfcy exhibits anticancer effects via induction of ERK-dependent paraptosis.

An Indonesian adolescent with Turner syndrome and β-thalassemia in low-resource setting: A case report and literature review article

Background

Turner syndrome and β-thalassemia very rarely occur together in an individual.

Case presentation

An Indonesian adolescent, 18 years old, complained is fatigue a week ago. She has a medical history of β-thalassemia for age 6 months and Turner syndrome identification for age 16 years. Meanwhile, she regular consumes deferasirox 500 mg every day. Physical examination showed pale conjunctiva and pale face. Body view similar children aged 13 years old. Laboratories investigation values included Hb of 7.7 gr/dL, MCV of 79.5 fL, MCH of 25.9 pg, MCHC of 28.6%, WBC of 6780/mm³, PLT of 242,000/mm³, AST of 15 U/L, ALT of 20 U/L, Ferritin of 1692.32 ng/mL, growth hormone of 0.468 ng/mL, Estradiol of <11.80 pg/mL, luteinizing hormone of 53.50 mIU/mL, and follicle-stimulating hormone of 115.19 mIU/mL. Chromosomal analysis showed Turner syndrome. The patient received a packed red cell transfusion of up Hb of 10 gr/dL, deferasirox 500 mg daily, and a contraceptive tablet. Due to financial issue in Indonesia, patient with Turner syndrome does not get proper hormonal therapy such as growth hormone, vitamin D supplementation, and other hormone replacement therapy.

Discussion

Turner syndrome and thalassemia in low-resource settings are challenges in themselves, so in their implementation, only thalassemia can be controlled, but for therapy, it does not show an improvement in prognosis.

Conclusion

Turner syndrome and thalassemia both worsen the patient's condition.

Iron in Alzheimer's Disease: From Physiology to Disease Disabilities

Reactive oxygen species (ROS) play a key role in the neurodegeneration processes. Increased oxidative stress damages lipids, proteins, and nucleic acids in brain tissue, and it is tied to the loss of biometal homeostasis. For this reason, attention has been focused on transition metals involved in several biochemical reactions producing ROS. Even though a bulk of evidence has uncovered the role of metals in the generation of the toxic pathways at the base of Alzheimer's disease (AD), this matter has been sidelined by the advent of the Amyloid Cascade Hypothesis. However, the link between metals and AD has been investigated in the last two decades, focusing on their local accumulation in brain areas known to be critical for AD. Recent evidence revealed a relation between iron and AD, particularly in relation to its capacity to increase the risk of the disease through ferroptosis. In this review, we briefly summarize the major points characterizing the function of iron in our body and highlight why, even though it is essential for our life, we have to monitor its dysfunction, particularly if we want to control our risk of AD.

Orphan Drug Use in Patients With Rare Diseases: A Population-Based Cohort Study

Background: Orphan drugs are used for the diagnosis, prevention and treatment of rare diseases that, in the European Union, are defined as disorders affecting no more than 5 persons in 10,000. So far, a total of around 800 orphan medicinal products have been approved by the European Medicines Agency, however the utilization profile of orphan drugs has yet to be explored. This study aimed at assessing the utilization profile of orphan drugs authorized for marketing by the Italian Medicines Agency using population-based data.

Methods: A total of 21 orphan drugs used in outpatient settings, approved in the European Union before or during the 2008–2018 period and involving 15 rare diseases, were included in the study. The monitored population included patients with one of the conditions surveilled by the population-based Tuscany Registry of Rare Diseases and diagnosed between 2000–2018. A multi-database approach was applied, by linking data from the registry with information collected in drug prescriptions databases. The prevalence and intensity of use were estimated for the selected orphan drugs and other non-orphan medications, used to treat the same rare disease and for which a change in the prevalence of use was hypothesized after authorization of the orphan drug.

Results: For some diseases (acquired aplastic anemia, tuberous sclerosis complex, most metabolic diseases) a low prevalence of orphan drugs use was observed (range between 1.1–12.5%). Conversely, orphan drugs were frequently used in hemophilia B, Wilson disease and idiopathic pulmonary fibrosis (maximum of 78.3, 47.6 and 41.8%, respectively). For hemophilia B and Leber’s hereditary optic neuropathy, there are currently no other medications used in clinical practice in addition to orphan drugs. Six orphan drugs were used for the treatment of pulmonary arterial hypertension, appearing the elective therapy for this disease, albeit with different utilization profiles (range of prevalence 1.7–55.6%).

Conclusion: To the best of our knowledge, this is the first study investigating the utilization profile of orphan drugs prescribed in a defined geographical area, and providing relevant information to monitor over time potential changes in the prevalence of these medications as well as in the health care decision making.

Iron toxicity in intracerebral hemorrhage: Physiopathological and therapeutic implications

Intracerebral hemorrhage (ICH)-induced brain injury is a continuous pathological process that involves the deterioration of neurological functions, such as sensory, cognitive or motor functions. Cytotoxic byproducts of red blood cell lysis, especially free iron, appear to be a significant pathophysiologic mechanism leading to ICH-induced injury. Free iron has a crucial role in secondary brain injury after ICH. Chelating iron may attenuate iron-induced neurotoxicity and may be developed as a therapeutic candidate for ICH treatment. In this review, we focused on the potential role of iron toxicity in ICH-induced injury and iron chelation therapy in the management of ICH. It will hopefully advance our understanding of the pathogenesis of ICH and lead to new approaches for treatment.

Labile iron, ROS, and cell death are prominently induced by haemin, but not by non-transferrin-bound iron

BACKGROUND

In transfusion-related iron overload, haem-derived iron accumulation in monocytes/macrophages is the initial event. When iron loading exceeds the ferritin storage capacity, iron is released into the plasma. When iron loading exceeds transferrin binding capacity, labile, non-transferrin-bound iron (NTBI) appears and causes organ injury. Haemin-induced cell death has already been investigated; however, whether NTBI induces cell death in monocytes/macrophages remains unclear.

MATERIAL AND METHODS

Human monocytic THP-1 cells were treated with haemin or NTBI, particularly ferric ammonium citrate (FAC) or ferrous ammonium sulfate (FAS). The intracellular labile iron pool (LIP) was measured using an iron-sensitive fluorescent probe. Ferritin expression was measured by western blotting.

RESULTS

LIP was elevated after haemin treatment but not after FAC or FAS treatment. Reactive oxygen species (ROS) generation and cell death induction were remarkable after haemin treatment but not after FAC or FAS treatment. Ferritin expression was not different between the FAC and haemin treatments. The combination of an iron chelator and a ferroptosis inhibitor significantly augmented the suppression of haemin cytotoxicity (p = 0.011).

DISCUSSION

The difference in LIP suggests the different iron traffic mechanisms for haem-derived iron and NTBI. The Combination of iron chelators and antioxidants is beneficial for iron overload therapy.

Comparative Efficacy and Safety Between Deferiprone and Deferasirox with Special Reference to Serum Ferritin Level and Cardiac Function in Bengali β-Thalassemia Major Children

Deferiprone (DFP) and deferasirox (DFX) are the most well-known, efficacious and safe chelators to reduce the serum ferritin (SF) level in multi transfused thalassemic children, although there are few reports available for assessing the efficacy between DFP and DFX. We compared the efficacy of DFP vs. DFX as iron chelating drugs in β-thalassemia major (β-TM) patients. Pediatric patients diagnosed to carry β-TM, aged between 2 and 10 years, were recruited. A suitable data collection form and questionnaire were used. Paired and unpaired t-tests were used to compare the safety and efficacy of the chelating drugs DFP and DFX. The mean SF level at the 12th month was found to be 3016.73 ± 670.04 ng/mL (p = 0.002) in the DFX-treated group, which was quite significant in contrast to DFP response, where the value was 3204.06 ± 690.15 ng/mL (p = 0.14). There is no statistically significant (p = 0.15) difference on relative changes of the left ventricular ejection fraction (LVEF), between these two groups. The adverse effects were transient and none of them required stoppage of therapy. Deferasirox is more effective when compared to DFP in reducing chelating drug-related complications and iron overload specially in multiple transfusion dependent β-TM patients.

Metallobiology and therapeutic chelation of biometals (copper, zinc and iron) in Alzheimer's disease: Limitations, and current and future perspectives

BACKGROUND

Alzheimer's disease (AD) is the most prevalent cause of cognitive impairment and dementia worldwide. The pathobiology of the disease has been studied in the form of several hypotheses, ranging from oxidative stress, amyloid-beta (Aβ) aggregation, accumulation of tau forming neurofibrillary tangles (NFT) through metal dysregulation and homeostasis, dysfunction of the cholinergic system, and to inflammatory and autophagic mechanism. However, none of these hypotheses has led to confirmed diagnostics or approved cure for the disease.

OBJECTIVE

This review is aimed as a basic and an encyclopedic short course into metals in AD and discusses the advances in chelation strategies and developments adopted in the treatment of the disease. Since there is accumulating evidence of the role of both biometal dyshomeostasis (iron (Fe), copper (Cu), and zinc (Zn)) and metal-amyloid interactions that lead to the pathogenesis of AD, this review focuses on unraveling therapeutic chelation strategies that have been considered in the treatment of the disease, aiming to sequester free and protein-bound metal ions and reducing cerebral metal burden. Promising compounds possessing chemically modified moieties evolving as multi-target ligands used as anti-AD drug candidates are also covered.

RESULTS AND CONCLUSION

Several multidirectional and multifaceted studies on metal chelation therapeutics show the need for improved synthesis, screening, and analysis of compounds to be able to effectively present chelating anti-AD drugs. Most drug candidates studied have limitations in their physicochemical properties; some enhance redistribution of metal ions, while others indirectly activate signaling pathways in AD. The metal chelation process in vivo still needs to be established and the design of potential anti-AD compounds that bi-functionally sequester metal ions as well as inhibit the Aβ aggregation by competing with the metal ions and reducing metal-induced oxidative damage and neurotoxicity may signal a bright end in chelation-based therapeutics of AD.

Neuro-Behavioral Correlates of Executive Dysfunctions in Dyslexia Over Development From Childhood to Adulthood

Dyslexia is a neurobiological learning disability in the reading domain that has symptoms in early childhood and persists throughout life. Individuals with dyslexia experience difficulties in academia and cognitive and emotional challenges that can affect wellbeing. Early intervention is critical to minimize the long-term difficulties of these individuals. However, the behavioral and neural correlates which predict dyslexia are challenging to depict before reading is acquired. One of the precursors for language and reading acquisition is executive functions (EF). The present review aims to highlight the current atypicality found in individuals with dyslexia in the domain of EF using behavioral measures, brain mapping, functional connectivity, and diffusion tensor imaging along development. Individuals with dyslexia show EF abnormalities in both behavioral and neurobiological domains, starting in early childhood that persist into adulthood. EF impairment precedes reading disability, therefore adding an EF assessment to the neuropsychological testing is recommended for early intervention. EF training should also be considered for the most comprehensive outcomes.

The iron chelator, PBT434, modulates transcellular iron trafficking in brain microvascular endothelial cells

Iron and other transition metals, such as copper and manganese, are essential for supporting brain function, yet over-accumulation is cytotoxic. This over-accumulation of metals, particularly iron, is common to several neurological disorders; these include Alzheimer’s disease, Parkinson’s disease, Friedrich’s ataxia and other disorders presenting with neurodegeneration and associated brain iron accumulation. The management of iron flux by the blood-brain barrier provides the first line of defense against the over-accumulation of iron in normal physiology and in these pathological conditions. In this study, we determined that the iron chelator PBT434, which is currently being developed for treatment of Parkinson’s disease and multiple system atrophy, modulates the uptake of iron by human brain microvascular endothelial cells (hBMVEC) by chelation of extracellular Fe²⁺. Treatment of hBMVEC with PBT434 results in an increase in the abundance of the transcripts for transferrin receptor (TfR) and ceruloplasmin (Cp). Western blot and ELISA analyses reveal a corresponding increase in the proteins as well. Within the cell, PBT434 increases the detectable level of chelatable, labile Fe²⁺; data indicate that this Fe²⁺ is released from ferritin. In addition, PBT434 potentiates iron efflux likely due to the increase in cytosolic ferrous iron, the substrate for the iron exporter, ferroportin. PBT434 equilibrates rapidly and bi-directionally across an hBMVEC blood-brain barrier. These results indicate that the PBT434-iron complex is not substrate for hBMVEC uptake and thus support a model in which PBT434 would chelate interstitial iron and inhibit re-uptake of iron by endothelial cells of the blood-brain barrier, as well as inhibit its uptake by the other cells of the neurovascular unit. Overall, this presents a novel and promising mechanism for therapeutic iron chelation.

Long-Term Effects of Iron Chelating Agents on Ocular Function in Patients with Thalassemia Major

Background

The aim of this study is to evaluate eye structures and function in patients receiving iron chelating therapy and to assess whether a correlation exists between the onset of ocular alterations and the intake of iron chelating drugs.

Methods

A prospective cohort study was performed. Eighty-eight patients, composed of children and adults with thalassemia major (TM) who are taking or had taken iron chelating drugs (deferoxamine, deferiprone or deferasirox), have been initially enrolled in the study. The final sample featured 80 patients, including 18 children and 62 adults. These subjects received an eye examination to evaluate intraocular pressure (IOP), best corrected visual acuity (BCVA), the presence of refractive defects, cornea, anterior chamber, lens, fundus oculi, visual field and mean retinal nerve fiber layer (RNFL) thickness. Logistic regression model analysis was performed in order to assess any correlation. In addition, a literature search regarding the relation between iron chelating drugs and ocular adverse events was carried out to compare the results obtained with the evidence in the literature.

Results

Logistic regression did not report a significant correlation between the intake of iron chelating drugs and the onset of anterior ocular segment alterations, lens opacities, retinal diseases, optical neuropathies, astigmatism, visual field and RNFL thickness defects. Logistic regression returned a statistically significant correlation between myopia and iron chelation therapy (p-value 0.04; OR 1.05) and also between presbyopia and total duration of therapy with deferoxamine (p-value 0.03; OR 1.21). Although intraocular pressure levels remained within the normal range, a significant correlation with the length of deferoxamine therapy has been found (p-value 0.002; association coefficient -0.12). A negative correlation between deferiprone and presbyopia has also been observed.

Conclusion

Iron chelation therapy is not associated with severe visual function alterations. Limitation of deferoxamine treatment can help prevent ocular complications. Deferiprone and/or deferasirox may be preferable, especially in patients over age 40 years.

The functional role of hemojuvelin in acute ischemic stroke

Our study aimed to establish the role of hemojuvelin (HJV) in acute ischemic stroke (AIS). We performed immunohistochemistry for HJV expression in human brain tissues from 10 AIS and 2 non-stroke autopsy subjects. Plasma HJV was measured in 112 AIS patients within 48 h after stroke. The results showed significantly increased HJV expression in brain tissues from AIS patients compare to non-stroke subjects. After adjusting for clinical variables, plasma levels of HJV within 48 h after stroke were an independent predictor of poor functional outcome three months post-stroke (OR:1.78, 95% CI: 1.03-3.07; P = 0.038). In basic part, Western blotting showed that HJV expression in mice brains was apparent at 3 h after middle cerebral artery occlusion (MCAO), and increased significantly at 72 h. In cultured cortical neurons, expression of HJV protein increased remarkably 24 h after oxygen glucose deprivation (OGD), and small interfering RNAs (siHJV) transfected OGD neurons had a lower apoptotic rate. Importantly, 72 h post-MCAO, HJV knockout mice had significantly smaller infarcts and less expression of cleaved caspase-3 protein compared with wild-type mice. In summary, HJV participates in the mechanisms of post-stroke neuronal injury, and that plasma HJV levels can be a potential early outcome indicator for AIS patients.

Up-regulation of hypoxia-inducible factor antisense as a novel approach to treat ovarian cancer

Ovarian cancer (OC) is estimated to kill ~14,000 women in the United States in 2019. Current chemotherapies to treat OC initially show therapeutic efficacy but frequently drug resistance develops, at which point therapies with alternative targets are needed. Herein, we are describing a novel approach to sensitize these tumors to standard chemotherapies by increasing the transcription of hypoxia-inducible factor antisense.

Methods: Genome-wide Bru-seq analysis was performed to fully capture the nascent transcriptional signature of OC cells treated with the gp130 inhibitor, SC144. In vitro and in vivo analysis, including characterization of hypoxia and select protein expression, combination with standard of care chemotherapy and antitumor efficacy were performed to assess the biological activity of SC144 on induction of hypoxia in OC cells.

Results: Bru-seq analysis of OVCAR8 cells treated with SC144 shows upregulation of hypoxia related genes. In addition, transcription of hypoxia-inducible factor antisense (HIF1A-AS2) was induced that in turn reduced expression of HIF-1α and simultaneously increased expression of NDRG1. Furthermore, we observed decreased protein levels of EGFR, Met, c-Myc, cyclin D1, MMP-2, MMP-9 and TF, and phosphorylation of Src and P130-cas. SC144-induced alterations of HIF-1α and NDRG1 were also confirmed in prostate cancer cells. Ciclopirox olamine (CPX) induces a cellular transcriptional profile comparable to SC144, suggesting a similar cellular mechanism of action between these two compounds. In addition, SC144 sensitized OC cells to olaparib, carboplatin and cisplatin, and shows better in vivo efficacy than CPX.

Conclusion: Induction of hypoxic stress responses through inhibition of gp130 represents a novel approach to design effective anticancer treatments in combination with standard-of-care chemotherapy in OC and the efficacy reported here strongly supports their clinical development.

Cardiomyopathy in Thalassemia: Quick Review from Cellular Aspects to Diagnosis and Current Treatments

BACKGROUND

Cardiomyopathic manifestations induced by continuous blood transfusion are the leading cause of death among patients with thalassemia major (TM). Despite introduction of chelation therapy, heart failure after cardiomyopathic manifestations is still a major threat to patients.

METHODS

We performed a search of relevant English-language literature, retrieving publications from the PubMed database and the Google Scholar search engine (2005-2018). We used "thalassemia major", "cardiomyopathy", "iron overload", "cardiac magnetic resonance T2" "chelation therapy", and "iron burden" as keywords.

RESULTS

The results of the studies we found suggest that cardiac hepcidin is a major regulator of iron homeostasis in cardiac tissue. Unlike previous assumptions, the heart appears to have a limited regeneration capability, originating from a small population of hypoxic cardiomyocytes.

CONCLUSIONS

Oxygen levels determine cardiomyocyte gene-expression patterns. Upregulation of cardiac hepcidin in hypoxia preserves cardiomyocytes from forming out of reactive oxygen species catalyzed by free cellular iron in cardiomyocytes. Using the limited regeneration capacity of cardiac cells and gaining further understanding of the cellular aspects of cardiomyopathic manifestations may help health care professionals to develop new therapeutic strategies.

Recent insight on improving the iron chelation efficacy of deferasirox by adjuvant therapy in transfusion dependent beta thalassemia children with sluggish response

Background: Deferasirox is the first line of treatment in iron overload. In spite of the many studies concerning the efficacy of deferasirox, some patients remain unresponsive to deferasirox.Methods: One hundred and sixty patients were enrolled in stratified-randomized controlled study. Patients were randomly divided into four regimens, group I (n = 40) received 30 mg/kg deferasirox, group II (n = 40) received 20 mg omeprazole and 30 mg/kg deferasirox, group III (n = 40) received 400 mg vitamin E and 30 mg/kg deferasirox and group IV (n = 40) received 420 mg silymarin and 30 mg/kg deferasirox. Blood specimens were collected from each patient for up to 24 h, and then plasma deferasirox concentrations were inspected.Results: Silymarin, Vitamin E, and omeprazole significantly increased the peak plasma concentration of deferasirox (P < 0.001) by 27.9, 14.9 and 2.4 fold, respectively, as compared to deferasirox alone. The bioavailability of deferasirox was improved up to 3.03, 3.57, and 4.98-fold, respectively, following administration of omeprazole, vitamin E, and silymarin compared to deferasirox alone.Conclusion: Silymarin, vitamin E, and omeprazole represent promising adjuvant therapy to improve the chelation efficacy of deferasirox that might also be further applied to enhance the pharmacokinetics of deferasirox to overcome the lack of response.

Economic Evaluation of Chelation Regimens for β-Thalassemia Major: a Systematic Review

Background

Deferoxamine (DFO) or Deferiprone (DFP) or Deferasirox (DFX) monotherapy and DFO and DFP combination therapy (DFO+DFP) were four commonly implemented now chelation regimens for the iron overloaded of β-thalassemia major. This systematic review aims to determine the cost-effectiveness of four chelation regimens and provide evidence for the rational use of chelation regimens for β-thalassemia major therapy in the clinic.

Methods

A systematic literature search in MEDLINE, EMBASE, the Cochrane Library, China Biology Medicine, China National Knowledge Infrastructure, VIP Data, and WanFang Data was conducted in April 2018. In addition, a manual search was performed. Two researchers, working independently, selected the papers, extracted the data, and assessed the methodological quality of the included documents. Each included paper was evaluated using a checklist developed by Drummond et al.

Results

The number of records was initially 968, and eight papers met the final eligibility criteria. All the included eight papers were cost-utility analyses, and their methodological quality was fair. In these eight papers, nineteen studies were present. Nine studies of DFX versus DFO had contradictory results. Out of the nineteen studies, three studies of DFX versus DFP established that using DFP was cost-effective. Three studies of DFP versus DFO proved that using DFP was cost-effective. One survey of DFO+DFP versus DFO found that using DFO was cost-effective. One study of DFO+DFP versus DFP found that using DFP was cost-effective. Moreover, there were two studies of DFO+DFP versus DFX, but we cannot be sure which one of two chelation regimens was cost-effective.

Conclusion

In brief, DFP is cost-effective, followed by DFO or DFX, when an iron chelator is to be used alone for β-thalassemia iron overload treatment. All studies that compared DFO+DFP with DFO (or DFP) monotherapy established that the DFO+DFP was not cost-effective. Existing studies about DFO+DFP versus DFX could not prove which one of two chelation regimens was cost-effective. However, due to the low number of DFO+DFP versus DFO (or DFP or DFX) monotherapy studies, more extensive, high-quality research is required for further analysis and confirmation of our findings. Moreover, the cost-effectiveness is not an absolute issue when in different countries (regions) the results are opposite for other countries (regions). As a result, the local/national context had a substantial influence on the results of the pharmacoeconomic evaluation.

Deferiprone exerts a dose-dependent reduction of liver iron in adults with iron overload

OBJECTIVE

While doses of deferiprone up to 75 mg/kg/d have been demonstrated to be effective in cardiac iron removal, their efficacy in the reduction of liver iron has been equivocal. The aim of this study was to evaluate the effect of deferiprone dose on liver iron concentrations in adult iron overload patients.

METHODS

A single-centered, retrospective, cohort observational study was conducted involving 71 patients exposed to deferiprone doses up to 113 mg/kg/d between January 2009 and June 2015 for a median of 33 months.

RESULTS

At the end of the study period, liver iron measured by R2 MRI was reduced by a mean 1.7 mg/g dw. A dose effect was observed, with incremental reductions of 2.8 mg/g dw in end of study LIC for every 10 mg/kg/d higher dose of deferiprone (P < 0.001). A dose effect was also observed in end of study ferritin and cardiac iron concentration measured by T2* MRI (P < 0.0001 and P = 0.048, respectively). No associations between adverse effects and deferiprone dose were observed, but there was a trend toward higher rates of agranulocytosis at higher doses and two of three hereditary hemochromatosis patients developed this complication.

CONCLUSION

The present study failed to demonstrate that the use of deferiprone at >90 mg/kg/d was associated with increased risk of agranulocytosis or neutropenia, but did demonstrate more effective liver iron control in iron overload patients.

Neuroinflammation, oxidative stress, and blood-brain barrier (BBB) disruption in acute Utah electrode array implants and the effect of deferoxamine as an iron chelator on acute foreign body response

The use of intracortical microelectrode arrays has gained significant attention in being able to help restore function in paralysis patients and study the brain in various neurological disorders. Electrode implantation in the cortex causes vasculature or blood-brain barrier (BBB) disruption and thus elicits a foreign body response (FBR) that results in chronic inflammation and may lead to poor electrode performance. In this study, a comprehensive insight into the acute molecular mechanisms occurring at the Utah electrode array-tissue interface is provided to understand the oxidative stress, neuroinflammation, and neurovascular unit (astrocytes, pericytes, and endothelial cells) disruption that occurs following microelectrode implantation. Quantitative real time polymerase chain reaction (qRT-PCR) was used to quantify the gene expression at acute time-points of 48-hr, 72-hr, and 7-days for factors mediating oxidative stress, inflammation, and BBB disruption in rats implanted with a non-functional 4 × 4 Utah array in the somatosensory cortex. During vascular disruption, free iron released into the brain parenchyma can exacerbate the FBR, leading to oxidative stress and thus further contributing to BBB degradation. To reduce the free iron released into the brain tissue, the effects of an iron chelator, deferoxamine mesylate (DFX), was also evaluated.

Effectiveness and Safety of Deferasirox in Thalassemia with Iron Overload: A Meta-Analysis

Deferasirox (DFX) has recently been used to treat thalassemia with iron overload; however, its long-term effectiveness and safety await multi-year studies. In this study, a systematic meta-analysis was performed to assess the effectiveness and safety of DFX in the treatment of thalassemia with iron overload. We performed a systematic electronic literature search for randomized controlled studies of DFX in the Embase, Medline, Cochrane, and Chinese Biomedical Literature (CBM) databases from January 1990 to May 2018. Particular attention was paid to mortality, serum ferritin (SF), liver iron concentration (LIC), myocardial iron concentration, and adverse events (AEs). Six studies comparing DFX with deferoxamine (DFO) and placebo were enrolled. DFX was not better than DFO in lowering SF and LIC, with an exception that high DFX dose (> 30 mg/kg/day) was superior to DFO in LIC. Otherwise, AEs such as gastrointestinal problems appeared to be more common with DFX. DFX does not seem to be superior to DFO at low dose. Similar efficacy seems to be achievable depending on dose. However, the convenient oral administration of DFX has a higher compliance rate.

Myocardial reperfusion injury and oxidative stress: Therapeutic opportunities

Acute myocardial infarction (AMI) is the leading cause of death worldwide. Its associated mortality, morbidity and complications have significantly decreased with the development of interventional cardiology and percutaneous coronary angioplasty (PCA) treatment, which quickly and effectively restore the blood flow to the area previously subjected to ischemia. Paradoxically, the restoration of blood flow to the ischemic zone leads to a massive production of reactive oxygen species (ROS) which generate rapid and severe damage to biomolecules, generating a phenomenon called myocardial reperfusion injury (MRI). In the clinical setting, MRI is associated with multiple complications such as lethal reperfusion, no-reflow, myocardial stunning, and reperfusion arrhythmias. Despite significant advances in the understanding of the mechanisms accounting for the myocardial ischemia reperfusion injury, it remains an unsolved problem. Although promising results have been obtained in experimental studies (mainly in animal models), these benefits have not been translated into clinical settings. Thus, clinical trials have failed to find benefits from any therapy to prevent MRI. There is major evidence with respect to the contribution of oxidative stress to MRI in cardiovascular diseases. The lack of consistency between basic studies and clinical trials is not solely based on the diversity inherent in epidemiology but is also a result of the methodological weaknesses of some studies. It is quite possible that pharmacological issues, such as doses, active ingredients, bioavailability, routes of administration, co-therapies, startup time of the drug intervention, and its continuity may also have some responsibility for the lack of consistency between different studies. Furthermore, the administration of high ascorbate doses prior to reperfusion appears to be a safe and rational therapy against the development of oxidative damage associated with myocardial reperfusion. In addition, the association with N-acetylcysteine (a glutathione donor) and deferoxamine (an iron chelator) could improve the antioxidant cardioprotection by ascorbate, making it even more effective in preventing myocardial reperfusion damage associated with PCA following AMI.

Calcium channel blockers for preventing cardiomyopathy due to iron overload in people with transfusion-dependent beta thalassaemia

BACKGROUND

Beta thalassaemia is a common inherited blood disorder. The need for frequent blood transfusions in this condition poses a difficult problem to healthcare systems. The most common cause of morbidity and mortality is cardiac dysfunction from iron overload. The use of iron chelation therapy has reduced the severity of systemic iron overload but specific, non-toxic treatment is required for removal of iron from the myocardium.

OBJECTIVES

To assess the effects of calcium channel blockers combined with standard iron chelation therapy in people with transfusion-dependent beta thalassaemia on the amount of iron deposited in the myocardium, on parameters of heart function, and on the incidence of severe heart failure or arrhythmias and related morbidity and mortality.

SEARCH METHODS

We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched ongoing trials databases, and the reference lists of relevant articles and reviews.Date of last search: 24 February 2018.

SELECTION CRITERIA

We included randomised controlled trials of calcium channel blockers combined with standard chelation therapy compared with standard chelation therapy alone or combined with placebo in people with transfusion-dependent beta thalassaemia.

DATA COLLECTION AND ANALYSIS

Two authors independently applied the inclusion criteria for the selection of trials. Two authors assessed the risk of bias of trials and extracted data and a third author verified these assessments. The authors used the GRADE system to assess the quality of the evidence.

MAIN RESULTS

Two randomised controlled trials (n = 74) were included in the review; there were 35 participants in the amlodipine arms and 39 in the control arms. The mean age of participants was 24.4 years with a standard deviation of 8.5 years. There was comparable participation from both genders. Overall, the risk of bias in included trials was low. The quality of the evidence ranged across outcomes from low to high, but the evidence for most outcomes was judged to be low quality.Cardiac iron assessment, as measured by heart T2*, did not significantly improve in the amlodipine groups compared to the control groups at six or 12 months (low-quality evidence). However, myocardial iron concentration decreased significantly in the amlodipine groups compared to the control groups at both six months, mean difference -0.23 mg/g (95% confidence interval -0.07 to -0.39), and 12 months, mean difference -0.25 mg/g (95% confidence interval -0.44 to -0.05) (low-quality evidence). There were no significant differences between treatment and control groups in serum ferritin (low-quality evidence), liver T2* (low-quality evidence), liver iron content (low-quality evidence) and left ventricular ejection fraction (low-quality evidence). There were no serious adverse events reported in either trial; however, one trial (n = 59) reported mild adverse events, with no statistically significant difference between groups (low-quality evidence).

AUTHORS' CONCLUSIONS

The available evidence does not clearly suggest that the use of calcium channel blockers is associated with a reduction in myocardial iron in people with transfusion-dependent beta thalassaemia, although a potential for this was seen. There is a need for more long-term, multicentre trials to assess the efficacy and safety of calcium channel blockers for myocardial iron overload, especially in younger children. Future trials should be designed to compare commonly used iron chelation drugs with the addition of calcium channel blockers to investigate the potential interplay of these treatments. In addition, the role of baseline myocardial iron content in affecting the response to calcium channel blockers should be investigated. An analysis of the cost-effectiveness of the treatment is also required.

Gonadal dysfunction in adult male patients with thalassemia major: an update for clinicians caring for thalassemia

INTRODUCTION

Hypogonadism is the most frequently reported endocrine complication, affecting 40%-80% of thalassemia major (TM) patients. The prevalence and severity of hypogonadism in TM varies among studies, depending on patients' age, genotype, transfusion frequency and starting age and efficiency of iron chelation. Areas covered: The diagnosis requires careful clinical assessment and appropriate laboratory testing. Its management is more complex compared to other 'classical' causes of hypogonadism because of multiple associated disorders (cardiac, hepatic and endocrine) and other contributing factors basically iron overload and iron toxicity. Expert commentary: Early recognition and treatment of hypogonadism in TM patients is most important to prevent late complications and to enhance the chances of parenthood. The goal of management is to restore deficient glandular function. If fertility is the issue and the testis is under-stimulated because of gonadotropin deficiency, it is possible to induce or restore spermatogenesis with exogenous gonadotropins in some patients. Assisted reproductive techniques may supplementary help to overcome previously untreatable causes of male infertility. These positive achievements should encourage health care providers to pay closer attention to the reproductive health of TM patients. This would involve the collaboration of clinicians caring for thalassemia with endocrinologists and specialists in assisted reproductive technologies.

Cost-Utility Analysis of Three Iron Chelators Used in Monotherapy for the Treatment of Chronic Iron Overload in β-Thalassaemia Major Patients: An Italian Perspective

PURPOSE

Deferiprone (DFP), deferasirox (DFX) and deferoxamine (DFO) are used in thalassaemia major (TM) patients to treat chronic iron overload. We evaluated the cost-effectiveness of DFP, compared with DFX and DFO monotherapy, from an Italian healthcare system perspective.

METHODS

A Markov model was used over a time horizon of 5 years. Italian-specific cost data were combined with Italian efficacy data. Costs and quality-adjusted life years (QALYs) were calculated for each treatment, with cost-effectiveness expressed as cost per QALY.

RESULTS

In all scenarios modelled, DFP was the dominant treatment strategy. Sensitivity analyses showed that DFP dominated the other treatments with a >99% likelihood of being cost-effective against DFX and DFO at a willingness to pay threshold of €20,000 per QALY.

CONCLUSIONS

DFP was the dominant and most cost-effective treatment for managing chronic iron overload in TM patients. Its use can result in substantial cost savings for the Italian healthcare system.

Safety profiles of iron chelators in young patients with haemoglobinopathies

BACKGROUND

This review describes the safety of deferoxamine (DFO), deferiprone (DFP), deferasirox (DFX) and combined therapy in young patients less than 25 yr of age with haemoglobinopathies.

METHODS

Searches in electronic literature databases were performed. Studies reporting adverse events associated with iron chelation therapy were included. Study and reporting quality was assessed using AHRQ Risk of Bias Assessment Tool and McMaster Quality Assessment Scale of Harms. Prospective clinical studies were pooled in a random-effects meta-analysis of proportions.

RESULTS

Safety data of 2040 patients from 34 studies were included. Ninety-two case reports of 246 patients were identified. DFX (937 patients) and DFP (667 patients) possess the largest published safety evidence. Fewer studies on combination regimens are available. Increased transaminases were seen in all regimens (3.9-31.3%) and gastrointestinal disorders with DFP and DFX (3.7-18.4% and 5.8-18.8%, respectively). Therapy discontinuations due to adverse events were low (0-4.1%). Reporting quality was selective and poor in most of the studies.

CONCLUSION

Iron chelation therapy is generally safe in young patients, and published data correspond to summary of product characteristics. Each iron chelation regimen has its specific safety risks. DFO seems not to be associated with serious adverse effects in recommended doses. In DFP and DFX, rare, but serious, adverse reactions can occur. Data on combined therapy are scarce, but it seems equally safe compared to monotherapy.

Combination Iron Chelation Therapy with Deferiprone and Deferasirox in Iron-Overloaded Patients with Transfusion-Dependent β-Thalassemia Major

There are few papers on the combination therapy of deferiprone (DFP) and deferasirox (DFX) in iron-overloaded patients with transfusion-dependent β-thalassemia major (β-TM). A total of 6 patients with β-TM (5 males and 1 female) with a mean age of 23.8±5.8 years (ranging from 17 to 31) used this treatment regimen. The mean doses of DFP and DFX were 53.9±22.2 and 29.3±6.8 mg/kg/day, respectively. The duration of treatment was 11.5±4.6 months. Their serum ferritin levels were measured to be 2800±1900 and 3400±1600 ng/mL before and after treatment, respectively (p<0.6). Their cardiac magnetic resonance imaging (MRI) T2* values were 16.69±15.35 vs 17.38±5.74 millisecond (ms) before and after treatment, respectively (p < 0.9). Although there was no significant difference between their cardiac MRI T2* values before and after treatment statistically, the values improved after combination therapy with DFP and DFX in most of the patients. Liver MRI T2 * values were changed from 2.12±0.98 to 3.03±1.51 ms after treatment (p < 0.01); Further, their liver T2* values and liver iron concentration (LIC) were improved after treatment. Our study found that cardiac MRI T2* values, liver MRI T2* values, and LIC were improved after combination therapy with DFP and DFX in β-TM patients and that DFP and DFX combination therapy could be used to alleviate cardiac and liver iron loading.

Hydroxypyridinone Chelators: From Iron Scavenging to Radiopharmaceuticals for PET Imaging with Gallium-68

Derivatives of 3,4-hydroxypyridinones have been extensively studied for in vivo Fe3+ sequestration. Deferiprone, a 1,2-dimethyl-3,4-hydroxypyridinone, is now routinely used for clinical treatment of iron overload disease. Hexadentate tris(3,4-hydroxypyridinone) ligands (THP) complex Fe3+ at very low iron concentrations, and their high affinities for oxophilic trivalent metal ions have led to their development for new applications as bifunctional chelators for the positron emitting radiometal, 68Ga3+, which is clinically used for molecular imaging in positron emission tomography (PET). THP-peptide bioconjugates rapidly and quantitatively complex 68Ga3+ at ambient temperature, neutral pH and micromolar concentrations of ligand, making them amenable to kit-based radiosynthesis of 68Ga PET radiopharmaceuticals. 68Ga-labelled THP-peptides accumulate at target tissue in vivo, and are excreted largely via a renal pathway, providing high quality PET images.

CONIFER - Non-Interventional Study to Evaluate Therapy Monitoring During Deferasirox Treatment of Iron Toxicity in Myelodysplastic Syndrome Patients with Transfusional Iron Overload

BACKGROUND

The non-interventional study CONIFER was designed to assess the safety and clinical practicability of deferasirox for the treatment of transfusional iron overload in myelodysplastic syndrome (MDS) patients.

METHODS

Patients included in the study were diagnosed with MDS and received at least 1 treatment with deferasirox. The observation period covered the time from the initial visit until the last follow-up.

RESULTS

The data of 99 patients with MDS scored mainly as International Prognostic Scoring System (IPSS) low and intermediate 1 were evaluated. The mean age of the participants was 75 years and 58% of the patients were male. Iron overload was assessed by serum ferritin level (mean baseline serum ferritin 2,080 ± 1,244 µg/l). Patients were treated for a mean duration of 16 months (mean daily dose at baseline 11.8 ± 7.0 mg/kg). Stratification of serum ferritin levels by deferasirox dose showed a reduction at the higher but no reduction at the lower dose (< 15 mg/kg vs. ≥ 15 mg/kg and < 20 mg/kg vs. ≥ 20 mg/kg). The majority of patients (81%) were affected by at least 1 adverse event, with decreased renal creatinine clearance being the most frequent.

CONCLUSION

Higher doses (≥ 15 mg/kg) of deferasirox effectively and safely reduced serum ferritin levels in MDS patients with transfusional iron overload.

Current and future directions in the treatment and prevention of drug-induced liver injury: a systematic review

While the pace of discovery of new agents, mechanisms and risk factors involved in drug-induced liver injury (DILI) remains brisk, advances in the treatment of acute DILI seems slow by comparison. In general, the key to treating suspected DILI is to stop using the drug prior to developing irreversible liver failure. However, predicting when to stop is an inexact science, and commonly used ALT monitoring is an ineffective strategy outside of clinical trials. The only specific antidote for acute DILI remains N-acetylcysteine (NAC) for acetaminophen poisoning, although NAC is proving to be beneficial in some cases of non-acetaminophen DILI in adults. Corticosteroids can be effective for DILI associated with autoimmune or systemic hypersensitivity features. Ursodeoxycholic acid, silymarin and glycyrrhizin have been used to treat DILI for decades, but success remains anecdotal. Bile acid washout regimens using cholestyramine appear to be more evidenced based, in particular for leflunomide toxicity. For drug-induced acute liver failure, the use of liver support systems is still investigational in the United States and emergency liver transplant remains limited by its availability. Primary prevention appears to be the key to avoiding DILI and the need for acute treatment. Pharmacogenomics, including human leukocyte antigen genotyping and the discovery of specific DILI biomarkers offers significant promise for the future. This article describes and summarizes the numerous and diverse treatment and prevention modalities that are currently available to manage DILI.

Role of vitamin C as an adjuvant therapy to different iron chelators in young β-thalassemia major patients: efficacy and safety in relation to tissue iron overload

BACKGROUND

Vitamin C, as antioxidant, increases the efficacy of deferoxamine (DFO).

AIM

To investigate the effects of vitamin C as an adjuvant therapy to the three used iron chelators in moderately iron-overloaded young vitamin C-deficient patients with β-thalassemia major (β-TM) in relation to tissue iron overload.

METHODS

This randomized prospective trial that included 180 β-TM vitamin C-deficient patients were equally divided into three groups (n = 60) and received DFO, deferiprone (DFP), and deferasirox (DFX). Patients in each group were further randomized either to receive vitamin C supplementation (100 mg daily) or not (n = 30). All patients received vitamin C (group A) or no vitamin C (group B) were followed up for 1 yr with assessment of transfusion index, hemoglobin, iron profile, liver iron concentration (LIC) and cardiac magnetic resonance imaging (MRI) T2*.

RESULTS

Baseline vitamin C was negatively correlated with transfusion index, serum ferritin (SF), and LIC. After vitamin C therapy, transfusion index, serum iron, SF, transferrin saturation (Tsat), and LIC were significantly decreased in group A patients, while hemoglobin and cardiac MRI T2* were elevated compared with baseline levels or those in group B without vitamin C. The same improvement was found among DFO-treated patients post-vitamin C compared with baseline data. DFO-treated patients had the highest hemoglobin with the lowest iron, SF, and Tsat compared with DFP or DFX subgroups.

CONCLUSIONS

Vitamin C as an adjuvant therapy possibly potentiates the efficacy of DFO more than DFP and DFX in reducing iron burden in the moderately iron-overloaded vitamin C-deficient patients with β-TM, with no adverse events.

Chelation in metal intoxication--Principles and paradigms

The present review provides an update of the general principles for the investigation and use of chelating agents in the treatment of intoxications by metals. The clinical use of the old chelators EDTA (ethylenediamine tetraacetate) and BAL (2,3-dimercaptopropanol) is now limited due to the inconvenience of parenteral administration, their own toxicity and tendency to increase the neurotoxicity of several metals. The hydrophilic dithiol chelators DMSA (meso-2,3-dimercaptosuccinic acid) and DMPS (2,3-dimercapto-propanesulphonate) are less toxic and more efficient than BAL in the clinical treatment of heavy metal poisoning, and available as capsules for oral use. In copper overload, DMSA appears to be a potent antidote, although d-penicillamine is still widely used. In the chelation of iron, the thiols are inefficient, since iron has higher affinity for ligands with nitrogen and oxygen, but the new oral iron antidotes deferiprone and desferasirox have entered into the clinical arena. Comparisons of these agents and deferoxamine infusions are in progress. General principles for research and development of new chelators are briefly outlined in this review.

Overview of Chelation Recommendations for Thalassaemia and Sickle Cell Disease

The long term consequences of iron toxicity are mostly reversible with effective iron chelation therapy. Recommendations for use of chelation therapy in transfusion dependent thalassaemia (TDT), sickle cell disease (SCD) and non transfusion dependent thalassaemia (NTDT) continue to evolve as our knowledge and clinical experience increases. Improved chelation options including drug combinations and a better understanding of condition specific factors may help to improve efficiency of chelation regimens and meet the needs of patients more effectively.

Randomized controlled trials of iron chelators for the treatment of cardiac siderosis in thalassaemia major

In conditions requiring repeated blood transfusion or where iron metabolism is abnormal, heart failure may result from accumulation of iron in the heart (cardiac siderosis). Death due to heart failure from cardiac iron overload has accounted for considerable early mortality in β-thalassemia major. The ability to detect iron loading in the heart by cardiovascular magnetic resonance using T2* sequences has created an opportunity to intervene in the natural history of such conditions. However, effective and well tolerated therapy is required to remove iron from the heart. There are currently three approved commercially available iron chelators: deferoxamine, deferiprone and deferasirox. We review the high quality randomized controlled trials in this area for iron chelation therapy in the management of cardiac siderosis.