Considerations for optimal iron use for anemia due to chronic kidney disease

Exploring progress in iron supplement formulation approaches for treating iron deficiency anemia through bibliometric and thematic analysis

Anemia is a severe health issue that affects around one-third of the global population. Therefore, the present study aims to conduct a bibliometric analysis to investigate the research trends regarding advancements on iron formulations in treating iron deficiency anemia via oral or parenteral route. This study adopts thematic and bibliometric methods on existing research on novel iron formulations. It also provides perspective into the existing understanding on treatment strategies for iron deficiency anemia. This study is conducted on 543 papers on various ferrous and ferric formulations used in the treatment of iron deficiency anemia. The study period is from 1977 to 2022, and the papers are identified from the Scopus database. The bibliometric analysis was carried out using the R tool's Bibliometrix package. The study discusses performance analysis, including annual publications, geographic analysis, relevant affiliations, journal analysis, and citation analysis. In addition, the conceptual structure, including the co-occurrence network, thematic map, thematic evolution, intellectual structure highlighting co-citation analysis, and social structure depicting the collaboration network and collaboration world map, are presented. The results showed increased research on formulation strategies for the treatment of iron deficiency anemia from 2010 onwards. The top 5 contributing countries are the USA, Italy, India, Germany, and the UK, and peer-reviewed journals from the area of nutrition. The most trending areas of study are iron deficiency anemia in pregnancy, chronic kidney diseases, inflammatory bowel diseases, and various intravenous formulations used in its treatment. The authors from Europe collaborate the most with authors from other countries. The study concludes that a safer and more effective iron formulation is needed to reduce the prevalence of anemia. The findings of the study are helpful in advancing research on innovative formulations for treating iron deficiency anemia. The insights from the study are helpful to policymakers in designing specific health policies and investing more in research and development of novel formulations for the treatment of iron deficiency anemia.

Natural Antioxidants in Anemia Treatment

Anemia, characterized by a decrease of the hemoglobin level in the blood and a reduction in carrying capacity of oxygen, is a major public health problem which affects people of all ages. The methods used to treat anemia are blood transfusion and oral administration of iron-based supplements, but these treatments are associated with a number of side effects, such as nausea, vomiting, constipation, and stomach pain, which limit its long-term use. In addition, oral iron supplements are poorly absorbed in the intestinal tract, due to overexpression of hepcidin, a peptide hormone that plays a central role in iron homeostasis. In this review, we conducted an analysis of the literature on biologically active compounds and plant extracts used in the treatment of various types of anemia. The purpose of this review is to provide up-to-date information on the use of these compounds and plant extracts, in order to explore their therapeutic potential. The advantage of using them is that they are available from natural resources and can be used as main, alternative, or adjuvant therapies in many diseases, such as various types of anemia.

Structure characterization of low molecular weight sulfate Ulva polysaccharide and the effect of its derivative on iron deficiency anemia

Sulfate Ulva polysaccharide with low molecular weight was prepared by enzymatic method and name SUE. The structural characterization of SUE and the effect of its derivative SUE-iron (III) on iron deficiency anemia were studied. Results showed SUE with molecular weight of 178 kDa were consisted of 57.9% rhamnose, 12.1% glucose, 16.3% glucuronic acid, and 13.7% xylose. The backbone contained (1 → 3, 4)-linked rhamnose, (1 → 4)-linked xylose, (1 → 6)-linked glucose and sulfate substitution was at C-3 of rhamnose. Due to high contents of sulfate group (23.7 ± 1.1%) and uronic acid, SUE-iron (III) with 20.3% iron content was synthesized. In order to evaluate the effects of SUE-iron (III) supplementation, an IDA animal model was created. After iron supplement administration, the SUE‑iron (III) showed effective effect on returning hemoglobin, red blood cells, serum iron, and erythropoietin to the normal levels. The hematological index of rats showed no difference from that in positive group. Besides, SUE-iron (III) is beneficial to alleviate inflammatory damage caused by IDA. These suggest that SUE-iron (III) might be exploited as safe and effective new iron supplement.

Iron Therapy Challenges for the Treatment of Nondialysis CKD Patients

The clinical consequences of untreated, severe anemia in patients with nondialysis CKD can be significant, but disparities exist in the anemia treatment guidelines and position papers issued from working groups and associations across the world. These differ in hemoglobin target and iron levels and their emphasis on various iron markers and other clinical outcomes. Not surprisingly, disparities are observed in anemia treatment strategies among patients with nondialysis CKD across different areas of the world. Over the past decade, the prescription and dosage of both iron therapies and erythropoiesis-stimulating agents have shifted, with notable regional differences observed. Moreover, there is ongoing debate regarding oral versus intravenous administration of iron. Compared with oral iron therapy, which often leads to gastrointestinal adverse events, low patient adherence, and low efficacy, intravenous iron administration has been associated with potential serious adverse events, such as anaphylaxis. New iron-based compounds and drugs currently under development are reviewed to describe their potential benefits in the treatment of anemia in patients with CKD. New oral compounds, including iron-based phosphate binders, heme iron polypeptide, and liposomal iron, show different rates of absorption with possibly different efficacy and improved tolerability. These new potential therapies offer health care providers additional anemia treatment options for their patients with CKD; however, the management of anemia in the CKD population continues to present challenges that require prospective studies to identify the optimal iron therapy for patients.

Iron deficiency in children with early chronic kidney disease

Iron deficiency (ID) contributes to the development of anemia in patients with chronic kidney disease (CKD). The frequency of ID in children with early CKD has not previously been reported. This was a retrospective chart review of children with CKD stages 2 and 3 followed at the CKD clinic of Children's Hospital of Michigan. ID was defined as low ferritin and transferrin saturation <20%. Patients on iron supplements were considered as iron-deficient cases. There were 50 patients included in the study (72% male) with a mean age of 10.31 (±5.21). The mean glomerular filtration rate (GFR) was 55.4 ml/min/1.73 m(2) (±14.61). ID was present in 42% of patients, out of whom almost half (42.9%) presented with anemia. Females had a higher frequency of ID (64.3%). The frequency of ID with anemia increased from 4.3% to 29.6%, (p = 0.03) in stage 2 to stage 3 CKD, respectively. The frequency of ID without anemia also increased with progression of CKD from stage 2 to stage 3, however, the difference was not statistically significant. ID is frequent in patients with early CKD. Monitoring of iron tests and treatment of ID is important in this population of patients.

FDA report: Ferumoxytol for intravenous iron therapy in adult patients with chronic kidney disease

On June 30, 2009, the United States Food and Drug Administration (FDA) approved ferumoxytol (Feraheme injection, AMAG Pharmaceuticals), an iron-containing product for intravenous (IV) administration, for the treatment of iron deficiency anemia in adult patients with chronic kidney disease (CKD). The safety and efficacy of ferumoxytol were assessed in three randomized, open-label, controlled clinical trials. Two trials evaluated patients with nondialysis dependent CKD and a third trial assessed patients undergoing hemodialysis. Randomization was either to ferumoxytol or oral iron. Ferumoxytol was administered as two 510 mg IV injections, separated by 3-8 days. Oral iron, Ferro-Sequels, was administered at a dose of 100 mg twice daily for 21 days. In all three clinical trials, ferumoxytol administration increased the mean blood hemoglobin (Hgb) concentrations by approximately 1.0 g/dL over the 35 day period, a mean increase that was greater than what was observed in patients receiving oral iron. Patients receiving ferumoxytol also had increases in blood transferrin saturation (TSAT) and ferritin values. For the proposed ferumoxytol dosing regimen, 4.9% of patients had serum ferritin >or=800 ng/mL and TSAT >or=50% post-treatment. The most important ferumoxytol safety concerns were hypersensitivity reactions and/or hypotension. Anaphylaxis or anaphylactoid reactions were reported in 0.2% of subjects, and other adverse reactions potentially associated with hypersensitivity (e.g., pruritus, rash, urticaria, or wheezing) were reported in 3.7%. Hypotension was observed in 1.9%, including three patients with serious hypotensive reactions. Ferumoxytol administration may transiently affect the diagnostic ability of magnetic resonance imaging and the drug label provides further information regarding this effect.

The safety and efficacy of intravenous ferric carboxymaltose in anaemic patients undergoing haemodialysis: a multi-centre, open-label, clinical study

BACKGROUND

Patients with chronic kidney disease (CKD) often present with iron depletion and iron deficiency anaemia (IDA) because of frequent blood (and iron) loss. Therapy consists of repletion of iron stores and intravenous (i.v.) iron has become the standard care in this setting. However, older i.v. iron preparations have their limitations. This study primarily investigated the safety, and also the efficacy, of ferric carboxymaltose (FCM), a next-generation i.v. iron formulation, given as a bolus-push injection in patients with CKD undergoing maintenance haemodialysis (HD).

METHODS

Patients (aged 18-65 years) with IDA undergoing HD received 100-200 mg of iron as FCM via an i.v. bolus-push injection into the HD venous line, two to three times weekly for <or=6 weeks. Safety assessments included incidence of adverse events (AEs). Treatment responders were patients attaining >or=1.0 g/dl increase in haemoglobin (Hb) from baseline at any time during the study. Enrolled patients (safety population) receiving >or=1 dose of study medication were included in the efficacy analyses [intent-to-treat (ITT) population].

RESULTS

Of 163 patients enrolled, 150 (92%) completed the study. The mean +/- SD total cumulative dose of iron as FCM administered was 2133.3 +/- 57.7 mg. In total, 193 AEs were reported in 89 out of 163 (54.6%) patients. Almost three-quarters of patients (73.6%) received erythropoiesis-stimulating agents (ESAs), but the dose remained stable during the study. Serious AEs occurred in 12 out of 163 (7.4%) patients and two patients died; none of these was considered by the investigator to be related to the study medication. Only five out of 163 (3.1%) patients discontinued study medication due to an AE. Overall, 100 out of 162 (61.7%; ITT population) patients were treatment responders, and mean Hb levels increased from 9.1 +/- 1.30 g/dl at baseline to 10.3 +/- 1.63 g/dl at follow-up.

CONCLUSIONS

FCM is well-tolerated and effective in the correction of Hb levels and iron stores in patients with IDA undergoing HD. As changes in anaemia treatment other than i.v. FCM (e.g. increased ESA doses) were not permitted during the study, the clinically relevant increase in Hb in the majority of patients can be solely attributed to efficient iron utilization. The incidence of AEs was as expected for this population.

Novel hollow microcapsules based on iron-heparin complex multilayers

Iron-polysaccharide complex have been extensively utilized in the treatment of iron deficiency anemia for parenteral administration. Herein, a novel iron-heparin complexed hollow capsules with nanoscaled wall thickness have been fabricated by means of alternating deposition of ferric ions (III) (Fe+) and heparin (Hep) onto the surface of submicroscaled (488 nm) and microscaled (10.55 microm) polystyrene latex particles via both electrostatic interaction and chemical complexation processes, followed by dissolution of the cores using tetrahydrofuran. Confocal micrographs and atomic force microscopy (AFM) images prove that iron-heparin complexed submicroscaled hollow capsules keep spherical shapes in solution and even after drying. The activated partial thromboplastin time (APTT) assay shows that complexing with ferric ions do not compromise the catalytic capacity of heparin to promote antithrombin III-mediated thrombin inactivation. The anticoagulant activity value of (Fe3+/Hep)8 capsules is evaluated to be about 95.7 U/mg, indicating that approximately 0.55 mg heparin was in 1 mg powder of submicroscaled (Fe3+/Hep)8 hollow capsules. Compared with the same dosage of heparin, iron-heparin complexed hollow capsules display a more prolonged anticoagulant duration than heparin. All these results reveal that such submicroscaled iron-heparin complexed hollow capsules have application potential as an injectable anticoagulant vehicle.

Evaluation of total-dose iron sucrose infusions in patients with iron deficiency anemia

PURPOSE

The safety and efficacy of a total-dose iron sucrose infusion protocol used in a large, tertiary care teaching hospital were studied.

METHODS

Nondialysis-dependent patients ages 18 years or older who received > or =250 mg of iron sucrose as a single i.v. infusion between January 2005 and January 2007 were eligible for study inclusion. The protocol for total-dose iron sucrose infusion was the same for all patients. The total dose of iron sucrose for each patient was calculated using an equation that included the desired hemoglobin (Hb) value, observed Hb level, ideal body weight, and sex. The calculated dose was divided into portions, rounded to the nearest 250 mg, and administered over four hours every other day. Outcomes measured included Hb, transferrin saturation, and serum ferritin values.

RESULTS

A total of 26 patients met the inclusion criteria. The mean +/- S.D. Hb concentration before total-dose iron sucrose infusion was 9.37 +/- 0.9 g/dL, and the mean +/- S.D. corpuscular volume was 75 +/- 7.1 mum(3). The mean +/- S.D. postinfusion Hb concentration for 19 patients for whom follow-up Hb levels were available was 11.4 +/- 1.2 g/dL, significantly higher than the 9.45 +/- 0.8 g/dL measured before the first infusion (p = 0.03). No significant adverse effects were reported in 47 of 49 infusions, with 2 patients experiencing mild nausea.

CONCLUSION

A treatment protocol consisting of alternate-day total-dose iron sucrose infusions was well tolerated and appeared to be effective in improving Hb concentrations in patients with iron deficiency anemia and without chronic kidney disease.

Treatment and costs associated with anemic chronic kidney disease patients

OBJECTIVE

The purpose of this paper is to provide an overview of the current therapeutic options afforded to anemic chronic kidney disease (CKD) patients and the costs of these interventions.

METHODOLOGY

Literature search of articles within Ovid MEDLINE between 1996 and 2007 that pertained to the treatment of anemia in chronic kidney disease patients.

RESULTS

Early detection and treatment of anemia associated with CKD has proven to provide positive cognitive and physical effects. Treatment options that increase iron storage and availability within the body and production of erythropoietin can assist in anemic CKD patients in achieving recommended levels of hemoglobin. Acknowledgement of the potential side effects associated with the medications selected to treat anemia can help in avoiding additional injury to the patient and thus reduce healthcare expenditure. A limitation of this review is that the search was performed within a single database.

CONCLUSIONS

Health care providers can play an active role in detecting anemia early and optimizing available treatment options. Future research on the effects of erythropoiesis-stimulating agents (ESA) on patients before they need dialysis, and a cost analysis between epoetin and darbepoetin alpha, would be beneficial.

Iron supplementation in the intensive care unit: when, how much, and by what route?

Derangements of iron metabolism may be present in critically ill patients who develop anemia during a stay in the intensive care unit. Iron supplementation may be appropriate, especially if an underlying nutritional disorder is present. It may be even more critical to replace iron when erythropoietin therapy is used because of the consumption of iron stores that occurs during heme synthesis. Iron therapy is not without risks, and controversy persists regarding the potential for iron overload and infections. Clinical trials that define the optimal dose, route, and timing of iron administration in critically ill patients are lacking. However, studies of iron supplementation in chronic kidney disease, pregnancy, and anemia of prematurity may provide some guidance about approaches to treatment. Clinical evidence and limitations that can assist clinicians in managing iron therapy in the intensive care unit are presented.

Advances in Anemia Management in Chronic Kidney Disease

The prevalence of chronic kidney disease (CKD) is increasing in the United States. Efforts to promote earlier intervention to screen for CKD and manage secondary complications are of paramount importance to improve overall care of this population. Anemia is a secondary complication of CKD that develops as kidney function declines. Historically, anemia management efforts have been primarily emphasized in patients with end-stage renal disease; however, early detection and treatment of anemia in the early stages of the disease are essential to prevent negative consequences of anemia such as reduced quality of life, left ventricular hypertrophy and mortality. With the increased prevalence of CKD and efforts focused on identifying this disorder early in its course, it is likely that more pharmacists will be involved in the management of CKD and secondary complications such as anemia. Treatment approaches must also be based on the more recently advocated guidelines from the National Kidney Foundation’s Kidney Disease Outcomes Quality Initiative (NKF-K/DOQI). This article reviews therapeutic issues of anemia of CKD, new agents for management, and the NKF-K/DOQI anemia management guidelines from a clinical perspective that will assist pharmacists involved in the care of these patients.