Nitrosative Stress and Apoptosis by Intravenous Ferumoxytol, Iron Isomaltoside 1000, Iron Dextran, Iron Sucrose, and Ferric Carboxymaltose in a Nonclinical Model

Chronic Kidney Disease as Oxidative Stress- and Inflammatory-Mediated Cardiovascular Disease

Generating reactive oxygen species (ROS) is necessary for both physiology and pathology. An imbalance between endogenous oxidants and antioxidants causes oxidative stress, contributing to vascular dysfunction. The ROS-induced activation of transcription factors and proinflammatory genes increases inflammation. This phenomenon is of crucial importance in patients with chronic kidney disease (CKD), because atherosclerosis is one of the critical factors of their cardiovascular disease (CVD) and increased mortality. The effect of ROS disrupts the excretory function of each section of the nephron. It prevents the maintenance of intra-systemic homeostasis and leads to the accumulation of metabolic products. Renal regulatory mechanisms, such as tubular glomerular feedback, myogenic reflex in the supplying arteriole, and the renin-angiotensin-aldosterone system, are also affected. It makes it impossible for the kidney to compensate for water-electrolyte and acid-base disturbances, which progress further in the mechanism of positive feedback, leading to a further intensification of oxidative stress. As a result, the progression of CKD is observed, with a spectrum of complications such as malnutrition, calcium phosphate abnormalities, atherosclerosis, and anemia. This review aimed to show the role of oxidative stress and inflammation in renal impairment, with a particular emphasis on its influence on the most common disturbances that accompany CKD.

Intravenous Irons: From Basic Science to Clinical Practice

Iron is an essential trace mineral necessary for life, and iron deficiency anaemia (IDA) is one of the most common haematological problems worldwide, affecting a sixth of the global population. Principally linked to poverty, malnutrition and infection in developing countries, in Western countries the pathophysiology of IDA is primarily linked to blood loss, malabsorption and chronic disease. Oral iron replacement therapy is a simple, inexpensive treatment, but is limited by gastrointestinal side effects that are not inconsequential to some patients and are of minimal efficacy in others. Third generation intravenous (IV) iron therapies allow rapid and complete replacement dosing without the toxicity issues inherent with older iron preparations. Their characteristic, strongly-bound iron-carbohydrate complexes exist as colloidal suspensions of iron oxide nanoparticles with a polynuclear Fe(III)-oxyhydroxide/oxide core surrounded by a carbohydrate ligand. The physicochemical differences between the IV irons include mineral composition, crystalline structure, conformation, size and molecular weight, but the most important difference is the carbohydrate ligand, which influences complex stability, iron release and immunogenicity, and which is a unique feature of each drug. Recent studies have highlighted different adverse event profiles associated with third-generation IV irons that reflect their different structures. The increasing clinical evidence base has allayed safety concerns linked to older IV irons and widened their clinical use. This review considers the properties of the different IV irons, and how differences might impact current and future clinical practice.

Cardiovascular, liver, and renal toxicity associated with an intravenous ferric carboxymaltose similar versus the originator compound

Background

Ferric carboxymaltose (FCM) is a stable, non-dextran-based intravenous iron complex used to treat iron deficiency of various etiologies. As FCM is a nonbiological complex drug and cannot be fully characterized by physicochemical analyses, it is important to demonstrate in nonclinical models that FCM similars (FCMS) have similar biodistribution.

Materials and methods

A total of 30 nonanemic rats were treated weekly with 40 mg iron/kg body weight intravenous FCM, FCMS, or isotonic saline (controls) for 4 weeks. Blood pressure, liver enzymes, and renal function were evaluated. In liver, heart, and kidney tissue, markers for oxidative stress (malondialdehyde to assess lipid peroxidation and antioxidant enzymes) and inflammation (TNFα and IL6) were measured. Iron deposits were localized.

Results

The FCMS-treated group had significantly lower blood pressure, higher liver enzymes, increased proteinuria, and reduced creatinine clearance versus the FCM and control groups by day 29. Serum iron and transferrin saturation were significantly higher with FCMS versus FCM or controls. Iron deposition was altered in FCMS-treated animals, with decreased ferritin deposits and iron deposition outside the physiological storage compartments. Markers for lipid peroxidation and antioxidant-enzyme activity were significantly increased after FCMS administration versus FCM and controls, as were inflammatory markers.

Conclusion

Results from this blinded nonclinical study demonstrated significant differences between the originator FCM and this FCMS.

Markers of oxidative/nitrosative stress and inflammation in lung tissue of rats exposed to different intravenous iron compounds

Iron deficiency anemia is a frequent complication in clinical conditions such as chronic kidney disease, chronic heart failure, inflammatory bowel disease, cancer, and excessive blood loss. Given the ability of iron to catalyze redox reactions, iron therapy can be associated with oxidative stress. The lung is uniquely susceptible to oxidative stress, and little is known about the effects of intravenous iron treatment in this organ. This study characterized changes in markers of oxidative/nitrosative stress and inflammation in the lung of non-iron deficient, non-anemic rats treated with five weekly doses (40 mg iron per kg body weight) of low molecular weight iron dextran (LMWID), iron sucrose (IS), ferric carboxymaltose (FCM), ferumoxytol (FMX), iron isomaltoside 1000 (IIM), or saline (control). Rats treated with LMWID, FMX, or IIM showed significant changes in most measures of oxidative/nitrosative stress, inflammation, and iron deposition compared to the saline-treated controls, with greatest changes in the LMWID treatment group. Increases in products of lipid peroxidation (thiobarbituric acid reactive substances) and protein nitrosation (nitrotyrosine) were consistent with increases in the activity of antioxidant enzymes (catalase, Cu,Zn-SOD, GPx), decreases in antioxidative capacity (reduced:oxidized GSH ratio), increased levels of transcription factors involved in the inflammatory pathway (NF-κB, HIF-1α), inflammatory cytokines (TNF-α, IL-6), adhesion molecules (VCAM-1), markers of macrophage infiltration (ED-1), and iron deposition (Prussian blue, ferritin). Since changes in measured parameters in FCM- or IS-treated rats were generally modest, the results suggest that FCM and IS have a low propensity to induce lung inflammation. The relevance of these findings to clinical safety profiles of the tested intravenous iron products requires further investigation.

Renal function in patients with non-dialysis chronic kidney disease receiving intravenous ferric carboxymaltose: an analysis of the randomized FIND-CKD trial

Background

Preclinical studies demonstrate renal proximal tubular injury after administration of some intravenous iron preparations but clinical data on renal effects of intravenous iron are sparse.

Methods

FIND-CKD was a 56-week, randomized, open-label, multicenter study in which patients with non-dialysis dependent chronic kidney disease (ND-CKD), anemia and iron deficiency without erythropoiesis-stimulating agent therapy received intravenous ferric carboxymaltose (FCM), targeting either higher (400–600 μg/L) or lower (100–200 μg/L) ferritin values, or oral iron.

Results

Mean (SD) eGFR at baseline was 34.9 (11.3), 32.8 (10.8) and 34.2 (12.3) mL/min/1.73 m² in the high ferritin FCM (n = 97), low ferritin FCM (n = 89) and oral iron (n = 167) groups, respectively. Corresponding values at month 12 were 35.6 (13.8), 32.1 (12.7) and 33.4 (14.5) mL/min/1.73 m². The pre-specified endpoint of mean (SE) change in eGFR from baseline to month 12 was +0.7 (0.9) mL/min/1.73 m² with high ferritin FCM (p = 0.15 versus oral iron), -0.9 (0.9) mL/min/1.73 m² with low ferritin FCM (p = 0.99 versus oral iron) and -0.9 (0.7) mL/min/1.73 m² with oral iron. No significant association was detected between quartiles of FCM dose, change in ferritin or change in TSAT versus change in eGFR. Dialysis initiation was similar between groups. Renal adverse events were rare, with no indication of between-group differences.

Conclusion

Intravenous FCM at doses that maintained ferritin levels of 100–200 μg/L or 400–600 μg/L did not negatively impact renal function (eGFR) in patients with ND-CKD over 12 months versus oral iron, and eGFR remained stable. These findings show no evidence of renal toxicity following intravenous FCM over a 1-year period.

Trial registrations

ClinicalTrials.gov NCT00994318 (first registration 12 October 2009).

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-017-0444-6) contains supplementary material, which is available to authorized users.

The Induction of Oxidative/Nitrosative Stress, Inflammation, and Apoptosis by a Ferric Carboxymaltose Copy Compared to Iron Sucrose in a Non-Clinical Model

INTRODUCTION

Ferric carboxymaltose is a next-generation polynuclear iron(III)-hydroxide carbohydrate complex for intravenous iron therapy belonging to the class of so-called non-biological complex drugs. The product characteristics and therapeutic performance of non-biological complex drugs are largely defined by the manufacturing process. A follow-on product, termed herein as ferric carboxymaltose similar, is available in India. Given that non-biological complex drugs may display differences in diverse product properties not characterisable by physico-chemical methods alone.

AIM

The aim is to assess the effects of this ferric carboxymaltose similar in our non-clinical model in non-anaemic healthy rats.

MATERIALS AND METHODS

Non-anaemic rats were treated with intravenous ferric carboxymaltose similar or iron sucrose both at (40 mg iron/kg body weight), or with saline solution (control) for four weeks, after which the animals were sacrificed. Parameters for tissue iron distribution, oxidative stress, nitrosative stress, inflammation and apoptosis were assessed by immunohistomorphometry.

RESULTS

Ferric carboxymaltose similar resulted in deranged iron distribution versus iron sucrose originator as indicated by increased serum iron, transferrin saturation and tissue iron(III) deposits as well as decreased ferritin deposits in the liver, heart and kidneys versus iron sucrose originator. Ferric carboxymaltose similar also increased significantly oxidative/nitrosative stress, pro-inflammatory, and apoptosis markers in the liver, heart and kidneys versus iron sucrose originator.

CONCLUSION

In our rat model, ferric carboxymaltose similar had a less favourable safety profile than iron sucrose originator, adversely affecting iron deposition, oxidative and nitrosative stress, inflammatory responses, with impaired liver and kidney function.

Optimizing iron delivery in the management of anemia: patient considerations and the role of ferric carboxymaltose

With the challenge of optimizing iron delivery, new intravenous (iv) iron-carbohydrate complexes have been developed in the last few years. A good example of these new compounds is ferric carboxymaltose (FCM), which has recently been approved by the US Food and Drug Administration for the treatment of iron deficiency anemia in adult patients who are intolerant to oral iron or present an unsatisfactory response to oral iron, and in adult patients with non-dialysis-dependent chronic kidney disease (NDD-CKD). FCM is a robust and stable complex similar to ferritin, which minimizes the release of labile iron during administration, allowing higher doses to be administered in a single application and with a favorable cost-effective rate. Cumulative information from randomized, controlled, multicenter trials on a diverse range of indications, including patients with chronic heart failure, postpartum anemia/abnormal uterine bleeding, inflammatory bowel disease, NDD-CKD, and those undergoing hemodialysis, supports the efficacy of FCM for iron replacement in patients with iron deficiency and iron-deficiency anemia. Furthermore, as FCM is a dextran-free iron-carbohydrate complex (which has a very low risk for hypersensitivity reactions) with a small proportion of the reported adverse effects in a large number of subjects who received FCM, it may be considered a safe drug. Therefore, FCM appears as an interesting option to apply high doses of iron as a single infusion in a few minutes in order to obtain the quick replacement of iron stores. The present review on FCM summarizes diverse aspects such as pharmacology characteristics and analyzes trials on the efficacy/safety of FCM versus oral iron and different iv iron compounds in multiple clinical scenarios. Additionally, the information on cost effectiveness and data on change in quality of life are also discussed.