Oral Ferric Maltol for the Treatment of Iron-Deficiency Anemia in Patients With CKD: A Randomized Trial and Open-Label Extension

Update on iron supplementation in patients with cancer-related anemia

INTRODUCTION

Numerous clinical trials affirm the efficacy and safety of IV iron to treat cancer-related anemia (CRA). Nonetheless, evaluation and treatment of CRA remains suboptimal.

AREAS COVERED

This review summarizes CRA therapy with a focus on iron deficiency and its treatment. The literature search was conducted using the National Library of Medicine (PubMed) database from 2004 to 2024. Topics reviewed include CRA pathophysiology, laboratory diagnosis of iron deficiency, a summary of clinical trial results using IV iron to treat CRA, and safety aspects.

EXPERT OPINION

Despite overwhelming positive efficacy and safety data, IV iron remains underutilized to treat CRA. This is likely due to persistent (unfounded) concerns about IV iron safety and lack of physician awareness of newer clinical trial data. This leads to poor patient quality of life and patient exposure to anemia treatments that have greater safety risks than IV iron. Solutions to this problem include increased educational efforts and considering alternative treatment models in which other providers separately manage CRA. The recent availability of new oral iron therapy products that are effective in treating anemia of inflammation has the potential to dramatically simplify the treatment of CRA.

Anemia of Chronic Kidney Disease-A Narrative Review of Its Pathophysiology, Diagnosis, and Management

Anemia is one of the most common chronic kidney disease (CKD) complications. It negatively affects patients' quality of life and clinical outcomes. The pathophysiology of anemia in CKD involves the interplay of various factors such as erythropoietin (EPO) deficiency, iron dysregulation, chronic inflammation, bone marrow dysfunction, and nutritional deficiencies. Despite recent advances in understanding this condition, anemia still remains a serious clinical challenge in population of patients with CKD. Several guidelines have been published with the aim to systematize the diagnostic approach and treatment of anemia; however, due to emerging data, many recommendations vary between publications. Recent studies indicate a potential of novel biomarkers to evaluate anemia and related conditions such as iron deficiency, which is often present in CKD patients. Our article aims to summarize the pathophysiology of anemia in CKD, as well as the diagnosis and management of this condition, including novel therapeutic approaches such as hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHI). Understanding these complex subjects is crucial for a targeted approach to diagnose and treat patients with anemia in CKD effectively.

Appropriateness of inpatient intravenous iron therapy in a Swiss tertiary care hospital

INTRODUCTION

Intravenous (IV) iron replacement is an established treatment for iron deficiency and is recommended in various medical guidelines, but cheaper oral iron formulations remain first-line therapy in several instances. Data on adherence to current prescription standards are lacking in Switzerland.

METHODS

Retrospective single center quality control study evaluating the appropriateness of IV iron replacement in 400 inpatients during 2019 and 2021 at a Swiss tertiary care hospital. Appropriateness of IV iron was assessed by expert chart review according to national and international guidelines.

RESULTS

IV iron prescriptions were assessed as inappropriate in 147 (37%) of cases (indication lacking in 13%, oral route preferred in 24%). Inappropriate prescribing was more common (p < .001) in surgical wards (66%) compared to medical units (48%) and the gynecologic ward (19%). Iron studies were lacking in 29% of inappropriate IV administrations. Insufficient replacement dosages were chosen in 38% of patients with appropriate prescription.

CONCLUSION

Based on current guidelines, inappropriate in-hospital prescription of IV iron was frequently observed. Considerable differences exist between hospital units, which are consistent with conflicting recommendations of professional societies. We recommend increased attention toward the prescription quality to avoid unnecessary, expensive, and potentially harmful use of IV iron.

Precision Medicine in Erythropoietin Deficiency and Treatment Resistance: A Novel Approach to Management of Anaemia in Chronic Kidney Disease

The study of anaemia is a well-developed discipline where the concepts of precision medicine have, in part, been researched extensively. This review discusses the treatment of erythropoietin (EPO) deficiency anaemia and resistance in cases of chronic kidney disease (CKD). Traditionally, erythropoietin-stimulating agents (ESAs) and iron supplementation have been used to manage anaemia in cases of CKD. However, these treatments pose potential risks, including cardiovascular and thromboembolic events. Newer treatments have emerged to address these risks, such as slow-release and low-dosage intravenous iron, oral iron supplementation, and erythropoietin-iron combination therapy. Another novel approach is the use of hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs). This review highlights the need for precision medicine targeting the genetic components of EPO deficiency anaemia in CKD and discusses individual variability in genes such as the erythropoietin gene (EPO), the interleukin-β gene (IL-β), and the hypoxia-inducible factor gene (HIF). Pharmacogenetic testing aims to provide targeted therapies and interventions that are tailored to the specific characteristics of an individual, thus optimising treatment outcomes and minimising resistance and adverse effects. This article concludes by suggesting that receptor modification has the potential to revolutionise the treatment outcomes of patients with erythropoietin deficiency anaemia through the integration of the mentioned approach.

Simultaneous determination of maltol and maltol glucuronide in human plasma and urine by HPLC-MS/MS: Application in clinical study in patients with iron deficiency

Ferric maltol has been used as an oral drug for iron deficiency. This study developed and fully validated the novel HPLC-MS/MS methods to determine maltol and maltol glucuronide simultaneously in plasma and urine. The protein precipitation was performed by addition of acetonitrile in the plasma samples. The dilution was performed for the urine samples to reach the suitable concentrations for injection. The multiple reaction monitoring (MRM) with an electrospray ionization (ESI) positive ion detection mode was used for the quantification. The maltol concentration linear ranges were 6.00-150 ng/mL and 0.100-10.0 μg/mL for the plasma and urine samples, respectively. The maltol glucuronide concentration linear ranges were 50.0-15000 ng/mL and 2.00-2000 μg/mL for the plasma and urine samples, respectively. These methods were applied to a single dose clinical study at a dose of 60 mg ferric maltol capsule in the patients with iron deficiency. The half-lives of maltol and maltol glucuronide were 0.90 ± 0.40 h and 1.02 ± 0.25 h in the iron deficiency patients, respectively. 39.52 ± 7.11 % maltol were excreted in urine in the form of maltol glucuronide.

Innovations thérapeutiques dans la prise en charge de l’anémie de la maladie rénale chronique Therapeutic innovations in the management of chronic kidney disease-associated anemia

Anemia is a common complication of chronic kidney disease (CKD). The insufficient erythropoietin (EPO) production by the kidneys and iron deficiency are the main causes. Iron supplementation and the administration of recombinant EPO are the main treatment modalities. New iron formulations that can be administered orally, intravenously or directly via the dialysate have recently been developed to improve efficacy and tolerance. Ferric citrate administered orally can effectively corrects anemia in case of iron deficiency and in addition chelate phosphate in the gut lumen. Ferric carboxymaltose allows intravenous administration of larger doses given less frequently. Ferric pyrophosphate citrate administered directly via the dialysate allows the compensation of iron losses during the hemodialysis session. HIF-prolyl-hydroxylase inhibitors are a new therapeutic class of erythropoiesis-stimulating agents. Orally administered, they act by stabilizing the HIF transcription factor involved in the initiation of erythropoietin production by hypoxia. Several clinical studies have recently evaluated these new molecules in comparison with recombinant EPO. In CKD patients not yet on dialysis or undergoing dialysis therapy non-inferiority in correcting anemia has been demonstrated compared with recombinant EPO. The decrease in circulating hepcidin they induce appears greater than that induced by injectable recombinant EPO. Presently available reports on the safety of HIF-prolyl-hydroxylase inhibitors are reassuring but need to be confirmed in longer-term studies of larger size. © 2022 Published by Elsevier Masson SAS on behalf of Société francophone de néphrologie, dialyse et transplantation.

Essential metals in health and disease

In total, twenty elements appear to be essential for the correct functioning of the human body, half of which are metals and half are non-metals. Among those metals that are currently considered to be essential for normal biological functioning are four main group elements, sodium (Na), potassium (K), magnesium (Mg), and calcium (Ca), and six d-block transition metal elements, manganese (Mn), iron (Fe), cobalt (Co), copper (Cu), zinc (Zn) and molybdenum (Mo). Cells have developed various metallo-regulatory mechanisms for maintaining a necessary homeostasis of metal-ions for diverse cellular processes, most importantly in the central nervous system. Since redox active transition metals (for example Fe and Cu) may participate in electron transfer reactions, their homeostasis must be carefully controlled. The catalytic behaviour of redox metals which have escaped control, e.g. via the Fenton reaction, results in the formation of reactive hydroxyl radicals, which may cause damage to DNA, proteins and membranes. Transition metals are integral parts of the active centers of numerous enzymes (e.g. Cu,Zn-SOD, Mn-SOD, Catalase) which catalyze chemical reactions at physiologically compatible rates. Either a deficiency, or an excess of essential metals may result in various disease states arising in an organism. Some typical ailments that are characterized by a disturbed homeostasis of redox active metals include neurological disorders (Alzheimer's, Parkinson's and Huntington's disorders), mental health problems, cardiovascular diseases, cancer, and diabetes. To comprehend more deeply the mechanisms by which essential metals, acting either alone or in combination, and/or through their interaction with non-essential metals (e.g. chromium) function in biological systems will require the application of a broader, more interdisciplinary approach than has mainly been used so far. It is clear that a stronger cooperation between bioinorganic chemists and biophysicists - who have already achieved great success in understanding the structure and role of metalloenzymes in living systems - with biologists, will access new avenues of research in the systems biology of metal ions. With this in mind, the present paper reviews selected chemical and biological aspects of metal ions and their possible interactions in living systems under normal and pathological conditions.

Recent and Emerging Therapies for Iron Deficiency in Anemia of CKD: A Review

Iron deficiency commonly contributes to the anemia affecting individuals with chronic kidney disease. Diagnostic criteria for iron deficiency in chronic kidney disease are explained. Mechanisms of functional and absolute iron deficiency and general treatment Principles as delineated in the Kidney Disease: Improving Global Outcomes guidelines are reviewed. Repletion of absolute iron deficits has progressed over time with the addition of better tolerated, more effective oral agents including ferric citrate, ferric maltol, and sucrosomial iron. Structural characteristics and trial data enabling regulatory approval of these novel oral agents are examined. Newer intravenous iron therapies including ferric carboxymaltose and ferric derisomaltose allow for fewer infusions and decreased risk of serious hypersensitivity reactions. Concerns about adverse events including cardiovascular events and infections are discussed. The potential risk of 6H syndrome due to these intravenous agents, including hypophosphatemia, osteomalacia, and pathologic fractures is emphasized. The proposed pathophysiology of 6H syndrome and hypophosphatemia is described. Ferric pyrophosphate citrate enables administration of iron for repletion through dialysate. Relative merits, costs, and risks of various iron agents such as hypersensitivity and 6H syndrome/hypophosphatemia are summarized.

Iron Replacement Therapy with Oral Ferric Maltol: Review of the Evidence and Expert Opinion

Iron deficiency is the most common cause of anemia globally and is frequently reported in patients with underlying inflammatory conditions, such as inflammatory bowel disease (IBD) and chronic kidney disease (CKD). Ferric maltol is a new oral iron replacement therapy designed to optimize iron absorption while reducing the gastrointestinal adverse events associated with unabsorbed free iron. Ferric maltol has been studied in clinical trials involving almost 750 adults and adolescents with iron-deficiency anemia associated with IBD, CKD, and other underlying conditions, and it has been widely used in clinical practice. It is approved for the treatment of adults with iron deficiency with or without anemia, independent of the underlying condition, and is commercially available in Europe and the United States. We review the published evidence for ferric maltol, which demonstrates consistent and clinically meaningful improvements in hemoglobin and measures of iron availability (ferritin and transferrin saturation) and shows that it is well-tolerated over long-term treatment for up to 64 weeks-an important consideration in patients with chronic underlying conditions such as IBD and CKD. We believe that ferric maltol is an effective, convenient, and well-tolerated treatment option for iron deficiency and iron-deficiency anemia, especially when long-term management of chronic iron deficiency is required. Writing support was provided by Shield Therapeutics (Gateshead, UK).