A Phase III, randomized, open-label trial of ferumoxytol compared with iron sucrose for the treatment of iron deficiency anemia in patients with a history of unsatisfactory oral iron therapy

Mechanical Forces Guide Axon Growth through the Nigrostriatal Pathway in an Organotypic Model

Reconstructing the nigrostriatal pathway is one of the major challenges in cell replacement therapies for Parkinson's disease due to the lack of enabling technologies capable of guiding the reinnervation of dopaminergic precursors transplanted into the substantia nigra toward the striatum. This paper examines nano-pulling, as a technology to enable the remote manipulation of axonal growth. Specifically, an organotypic model consisting of co-cultures of the substantia nigra and the striatum is developed to demonstrate that when cortical neural progenitors are transplanted into the substantia nigra, nano-pulling can guide and enhance the elongation of neural projections toward the striatum. To provide additional evidence, induced pluripotent stem cell-derived dopaminergic progenitor neurospheres are generated and it is shown that nano-pulling can induce guided growth and promote the maturation of their neural processes. Altogether, this study demonstrates the potential of nano-pulling as an emerging technique to promote directed reinnervation within the central nervous system.

Postoperative intravenous iron to treat iron-deficiency anaemia in patients undergoing cardiac surgery: a protocol for a pilot, multicentre, placebo-controlled randomized trial (the POAM trial)

Background

Iron-deficiency anaemia, occurring in 30-40% of patients undergoing cardiac surgery, is an independent risk factor for adverse outcomes. Our long-term goal is to assess if postoperative i.v. iron therapy improves clinical outcomes in patients with preoperative iron-deficiency anaemia undergoing cardiac surgery. Before conducting a definitive RCT, we first propose a multicentre pilot trial to establish the feasibility of the definitive trial.

Methods

This internal pilot, double-blinded, RCT will include three centres. Sixty adults with preoperative iron-deficiency anaemia undergoing non-emergency cardiac surgery will be randomised on postoperative day 2 or 3 to receive either blinded i.v. iron (1000 mg ferric derisomaltose) or placebo. Six weeks after surgery, patients who remain iron deficient will receive a second blinded dose of i.v. iron according to their assigned treatment arm. Patients will be followed for 12 months. Clinical practice will not be otherwise modified. For the pilot study, feasibility will be assessed through rates of enrolment, protocol deviations, and loss to follow up. For the definitive study, the primary outcome will be the number of days alive and out of hospital at 90 days after surgery.

Ethics and dissemination

The trial has been approved by the University Health Network Research Ethics Board (REB # 22-5685; approved by Clinical Trials Ontario funding on 22 December 2023) and will be conducted in accordance with the Declaration of Helsinki, Good Clinical Practices guidelines, and regulatory requirements.

Clinical trial registration

NCT06287619.

Expert consensus guidelines: Intravenous iron uses, formulations, administration, and management of reactions

Intravenous iron has become an essential component for the treatment of iron deficiency and iron deficiency anemia. Individuals administering Intravenous iron should have knowledge in intravenous iron administration, including a pre-infusion assessment to evaluate infusion reaction risks, pre- and post-infusion monitoring, identification of and management of infusion reactions, accurate documentation of these reactions, laboratory monitoring and recognition and management of treatment-emergent hypophosphatemia. This comprehensive consensus provides step-by-step guidance and tools for practitioners to promote safe delivery of intravenous iron, recognition, and management of infusion reactions and treatment-emergent hypophosphatemia.

Iron deficiency anemia among women: An issue of health equity

Iron deficiency is the most common and widespread nutritional deficiency in the world. For women, the risk of iron deficiency and iron deficiency anemia increases due to iron demands during pregnancy and regular iron losses due to menstruation during reproductive years. These interrelated conditions are of public health concern as they are highly prevalent, and the negative consequences such as chronic fatigue, cognitive impairment and poor quality of life are broad and multifaceted. People of low socioeconomic status are at higher risk of iron deficiency due to low intake of expensive iron-rich foods, and decreased access to healthcare. In this review, we applied a health equity lens to describe the current state of care for women with iron deficiency with or without anemia. We have highlighted several structural challenges that span from the laboratory diagnosis, inconsistent screening guidelines, and stigma associated with heavy menstrual bleeding, to treatment barriers.

The Story of Ferumoxytol: Synthesis Production, Current Clinical Applications, and Therapeutic Potential

Ferumoxytol, approved by the U.S. Food and Drug Administration in 2009, is one of the intravenous iron oxide nanoparticles authorized for the treatment of iron deficiency in chronic kidney disease and end-stage renal disease. With its exceptional magnetic properties, catalytic activity, and immune activity, as well as good biocompatibility and safety, ferumoxytol has gained significant recognition in various biomedical diagnoses and treatments. Unlike most existing reviews on this topic, this review primarily focuses on the recent clinical and preclinical advances of ferumoxytol in disease treatment, spanning anemia, cancer, infectious inflammatory diseases, regenerative medicine application, magnetic stimulation for neural modulation, etc. Additionally, the newly discovered mechanisms associated with the biological effects of ferumoxytol are discussed, including its magnetic, catalytic, and immunomodulatory properties. Finally, the summary and future prospects concerning the treatment and application of ferumoxytol-based nanotherapeutics are presented.

Brand ferumoxytol vs. generic ferumoxytol comparison across two dosing regimens: a cardiac MRI image quality study

BACKGROUND

Ferumoxytol is becoming more widely used as an off-label blood-pool contrast agent for MR angiography (MRA) and four-dimensional (4D) flow imaging in pediatric cardiovascular disease. Brand and generic versions of ferumoxytol are available with no information on relative efficacy as a contrast agent and safety profiles.

OBJECTIVE

This study evaluates patient safety and image quality of comparable dosages of generic ferumoxytol (GF) versus brand ferumoxytol (BF) with the following hypotheses: (1) Reducing the contrast dosage from 3 to 2 mg/kg will not affect imaging quality and diagnostic accuracy of MRA and four-dimensional 4D flow. (2) GF and BF have similar image quality. (3) GF and BF have similar patient safety profiles.

MATERIALS AND METHODS

In an IRB-approved retrospective study, changes in vitals/clinical status between baseline, during infusion, and 30 min post-infusion were analyzed in 3 groups: group 1 (3 mg/kg BF, 216 patients, age: 19.29 ± 11.71 years ranging from 2 months to 62 years), group 2 (2 mg/kg BF, 47 patients, age: 15.35 ± 8.56 years ranging from 10 days to 41 years), and group 3 (2 mg/kg GF, 127 patients, age: 17.16 ± 12.18 years ranging from 6 days to 58 years). Both pediatric and adult patients with congenital heart disease (CHD) indications were included within the study. Adverse reactions were classified as mild, moderate, or severe. Quantitative analysis of MR image quality was performed with signal-to-noise ratio (SNR) on MRA and velocity-to-noise ratio (VNR) on 4D flow. Qualitative grading of imaging features was performed by 2 experienced observers. Two-way analysis of variance (ANOVA) and chi-square tests were used for comparison with a P value of ≤ 0.05 used for significance.

RESULTS

No statistical difference was found in clinical status and vital signs (P>0.05). No severe reactions were reported. 7.9% of GF patients experienced an adverse reaction compared to 2.3% with 3 mg/kg BF and 8.4% with 2 mg/kg BF. There was no statistical difference in SNR between the 3 groups (P>0.05). For 4D flow, 2 mg/kg GF demonstrated an increase in VNR compared to 2 mg/kg BF (P = 0.005). The qualitative scores for MRA and 4D flow were high (≥ 3) across all 3 groups.

CONCLUSIONS

No significant difference was identified between 2 mg/kg GF and BF in terms of safety profile and image quality. Given the small sample size of this study, further studies are required to confirm these results.

Patient-Reported Outcomes After Ferric Carboxymaltose Treatment for Iron Deficiency Anemia: A Prospective Observational Study

Background

Iron deficiency anemia (IDA) is a common cause of fatigue and impaired quality of life. The present study aimed to evaluate the impact of intravenous iron supplementation with ferric carboxymaltose (FCM) on fatigue, physical function, and general health among patients with IDA attending routine clinical care.

Methods

This was a prospective, single arm, observational study of adult patients prescribed with intravenous FCM for the treatment of IDA during routine clinical care. We used Patient-Reported Outcomes Measurement Information System (PROMIS) instruments to evaluate fatigue (PROMIS Short Form v1.0 13a [FACIT-Fatigue]), general health status (PROMIS Scale v1.2), and physical function (PROMIS Short Form v2.0 4a) before and at 3 and 6 months after FCM treatment.

Results

A total of 152 patients were enrolled. Mean age was 47.4 ± 16.0 years and 82.2% were female. Mean serum hemoglobin was 10.2 ± 1.4 g/dL at baseline. All patients were treated with at least one FCM dose at baseline, with 77.6% receiving a two-dose treatment course. The mean baseline FACIT-Fatigue score was 61.0 ± 9.0, improving significantly to 50.2 ± 9.5 at 3 months after FCM treatment. A minimum 5-point improvement, pre-defined as clinically meaningful, was seen in the FACIT-Fatigue, PROMIS Global Physical Health, Global Mental Health and PROMIS Physical Function scores for 72.7%, 52.8%, 41.7% and 39.8% of patients at 3 months (p < 0.0001 for each change from baseline), with statistically significant improvement continuing at 6 months. Mean serum hemoglobin was significantly increased at both 3 and 6 months (12.8 g/dL [N = 44] and 12.4 g/dL [N = 54], respectively).

Conclusion

IDA patients attending routine clinical practice reported substantial levels of fatigue and impairments in physical function and global health prior to intravenous iron treatment. Patients experienced significant improvements in fatigue symptoms, physical function, and global health at 3 months after treatment with FCM, which were sustained at 6 months.

Detecting monocyte trafficking in an animal model of glioblastoma using R2* and quantitative susceptibility mapping

BACKGROUND

The role of tumor-associated macrophages (TAMs) in glioblastoma (GBM) disease progression has received increasing attention. Recent advances have shown that TAMs can be re-programmed to exert a pro-inflammatory, anti-tumor effect to control GBMs. However, imaging methods capable of differentiating tumor progression from immunotherapy treatment effects have been lacking, making timely assessment of treatment response difficult. We showed that tracking monocytes using iron oxide nanoparticle (USPIO) with MRI can be a sensitive imaging method to detect therapy response directed at the innate immune system.

METHODS

We implanted syngeneic mouse glioma stem cells into C57/BL6 mice and treated the animals with either niacin (a stimulator of innate immunity) or vehicle. Animals were imaged using an anatomical MRI sequence, R₂^* mapping, and quantitative susceptibility mapping (QSM) before and after USPIO injection.

RESULTS

Compared to vehicles, niacin-treated animals showed significantly higher susceptibility and R₂^*, representing USPIO and monocyte infiltration into the tumor. We observed a significant reduction in tumor size in the niacin-treated group 7 days later. We validated our MRI results with flow cytometry and immunofluoresence, which showed that niacin decreased pro-inflammatory Ly6C high monocytes in the blood but increased CD16/32 pro-inflammatory macrophages within the tumor, consistent with migration of these pro-inflammatory innate immune cells from the blood to the tumor.

CONCLUSION

MRI with USPIO injection can detect therapeutic responses of innate immune stimulating agents before changes in tumor size have occurred, providing a potential complementary imaging technique to monitor cancer immunotherapies.

MANUSCRIPT HIGHLIGHT

We show that iron oxide nanoparticles (USPIOs) can be used to label innate immune cells and detect the trafficking of pro-inflammatory monocytes into the glioblastoma. This preceded changes in tumor size, making it a more sensitive imaging technique.

Ferumoxytol: an emerging therapeutic for iron deficiency anemia

INTRODUCTION

Iron deficiency anemia (IDA) is common worldwide, and various iron replacement therapies are available. Ferumoxytol is an injectable, high-dose iron formulation (510 mg) that can be administered over a short period (15 min) without test administration. The drug was approved by the Food and Drug Administration in 2009 for the treatment of IDA in patients with chronic kidney disease (CKD), and in 2018, the indication was expanded to include patients without CKD.

AREAS COVERED

This paper reviews studies testing the efficacy and safety of ferumoxytol in treating IDA compared with other iron formulations.

EXPERT OPINION

There is substantial evidence that ferumoxytol is effective for the treatment of IDA. The efficacy of ferumoxytol in improving anemia is comparable to that of iron sucrose and ferric carboxymaltose (FCM) and superior to that of oral iron or a placebo in replenishing iron stores. Treatment with ferumoxytol, although more expensive, is cost-effective for outpatients requiring parenteral administration because it requires fewer doses and shorter dosing times per dose. Ferumoxytol also causes less frequent hypophosphatemia than FCM. Currently, its use in children and pregnant women is under consideration, which may provide important information for the future applications of ferumoxytol in larger numbers of patients.

Magnetic particle imaging for assessment of cerebral perfusion and ischemia

Stroke is one of the leading worldwide causes of death and sustained disability. Rapid and accurate assessment of cerebral perfusion is essential to diagnose and successfully treat stroke patients. Magnetic particle imaging (MPI) is a new technology with the potential to overcome some limitations of established imaging modalities. It is an innovative and radiation-free imaging technique with high sensitivity, specificity, and superior temporal resolution. MPI enables imaging and diagnosis of stroke and other neurological pathologies such as hemorrhage, tumors, and inflammatory processes. MPI scanners also offer the potential for targeted therapies of these diseases. Due to lower field requirements, MPI scanners can be designed as resistive magnets and employed as mobile devices for bedside imaging. With these advantages, MPI could accelerate and improve the diagnosis and treatment of neurological disorders. This review provides a basic introduction to MPI, discusses its current use for stroke imaging, and addresses future applications, including the potential for clinical implementation. This article is categorized under: Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease.

Ferumoxytol for the treatment of iron deficiency and iron-deficiency anemia of pregnancy

Introduction:

A litany of recent evidence supports the morbidity of intra-natal iron-deficiency anemia and its prodrome, iron deficiency. Oral iron administered during second and third trimesters does not get to the developing fetus if the mother is iron deficient. This is especially concerning as the rapidly developing fetal brain is in particular need of iron sufficiency. Intra-natal iron deficiency is associated with autism, schizophrenia and abnormal brain structure. The obstetrical literature reports an unacceptably high incidence of gastrointestinal adverse events with oral iron. The time iron honored standard in the United States for intravenous iron replenishment in gravidas is iron sucrose. While safe and effective, four to seven visits are required to accomplish what newer formulations can achieve with one.

Methods:

Ferumoxytol is a superparamagnetic iron oxide linked to polyglucose sorbitol carboxymethylether-binding elemental iron tightly allowing administration of complete replacement doses in 15–30 min. Herein, we report the results of 131 consecutive, non-selected, iron-deficient second- and third-trimester pregnant women who received either 510 mg of intravenous (IV) ferumoxytol twice or 1020 mg once.

Results:

Hemoglobin and iron parameter increments were highly statistically significant. No adverse events were reported. We report how a single infusion is safe and effective as the same dose over two visits, saving an unnecessary visit and IV placement, while reducing cost.

Conclusion:

Ferumoxytol represents an efficacious and safe method of administration of IV iron which improves convenience for patients and practitioners, and is cost saving due to fewer visits.

Plain language summary

One or two infusions of intravenous iron for iron deficiency or iron-deficiency anemia of pregnancy simplifies care

This study was conducted to highlight the inconvenience of multiple doses of IV iron and how administering the same dose in one or two infusions simplifies care. We report how a single infusion is as safe and effective as the same dose over two visits, saving an unnecessary visit and IV placement, while reducing cost. This study supports a growing body of evidence, to date, unreported, with ferumoxytol in pregnancy, reporting improved convenience and decreased costs with higher doses of IV iron in one or two visits.

Vascular applications of ferumoxytol-enhanced magnetic resonance imaging of the abdomen and pelvis

Ferumoxytol is an injectable ultrasmall superparamagnetic iron oxide that has been gaining interest regarding its off-label use as an intravenous contrast agent in magnetic resonance imaging (MRI). Due to its large particle size, its use with MRI produces exquisite images of blood vessels with little background contamination or parenchymal enhancement of the abdominopelvic organs, except for the liver and spleen. Because ferumoxytol is neither an iodinated nor a gadolinium-based contrast agent, there are no restrictions for its use in patients with poor renal function. This article will highlight normal features in ferumoxytol-enhanced MRI in the abdomen and pelvis as well as its applications in evaluating vascular pathology, presurgical planning, and other problem solving.

Safety and efficacy of a single total dose infusion (1020 mg) of ferumoxytol

Purpose:

Iron deficiency anemia (IDA) is the most common type of anemia. A single dose infusion of intravenous (IV) iron is a convenient treatment option. Ferumoxytol is an IV formulation of iron that is typically given in two doses of 510 mg each. Utilizing a single dose of 1020 mg over 15 min has previously been described as safe and effective. In July 2018, we began to administer a single 1020 mg dose of ferumoxytol to patients needing IV iron replacement at the North Florida/South Georgia Veterans Health System. To evaluate the impact of this change, a utilization review was conducted.

Methods:

Outcomes of all patients who received ferumoxytol injections in the 6 months prior to and after the dosing strategy change were analyzed. A total of 140 patients, who received 270 separate IV ferumoxytol infusions, were included in the analysis.

Results:

No significant difference in safety was observed, with one infusion reaction occurring in each group (p = 1.00). Efficacy also appeared equivalent with no significant difference between the change in hemoglobin for those who received a single 1020 mg dose versus those who received two 510 mg doses (p = 0.764). As expected, those who received a single total dose infusion of 1020 mg had less clinic utilization (p < 0.0001).

Conclusion:

In summary, ferumoxytol administered as a 1020 mg single dose infusion was more convenient and should be considered a safe and effective treatment option for IDA.

Diagnostic and Therapeutic Nanomedicine

Nanotechnology has been widely applied to medical interventions for prevention, diagnostics, and therapeutics of diseases, and the application of nanotechnology for medical purposes, which is called as a term "nanomedicine" has received tremendous attention. In particular, the design and development of nanoparticle for biosensors have received a great deal of attention, since those are most impactful area of clinical translation showing potential breakthrough in early diagnosis of diseases such as cancers and infections. For example, the nanoparticles that have intrinsic unique features such as magnetic responsive characteristics or photoluminescence can be utilized for noninvasive visualization of inner body. Drug delivery that makes use of drug-containing nanoparticles as a carrier is another field of study, in which the particulate form nanomedicine is given by parenteral administration for further systemic targeting to pathological tissues. In addition, encapsulation into nanoparticles gives the opportunity to secure the sensitive therapeutic payloads that are readily degraded or deactivated until reached to the target in biological environments, or to provide sufficient solubilization (e.g., to deliver compounds which have physicochemical properties that strongly limit their aqueous solubility and therefore systemic bioavailability). The nanomedicine is further intended to enhance the targeting index such as increased specificity and reduced false binding, thus improve the diagnostic and therapeutic performances. In this chapter, principles of nanomaterials for medicine will be thoroughly covered with applications for imaging-based diagnostics and therapeutics.

Manipulation of Axonal Outgrowth via Exogenous Low Forces

Neurons are mechanosensitive cells. The role of mechanical force in the process of neurite initiation, elongation and sprouting; nerve fasciculation; and neuron maturation continues to attract considerable interest among scientists. Force is an endogenous signal that stimulates all these processes in vivo. The axon is able to sense force, generate force and, ultimately, transduce the force in a signal for growth. This opens up fascinating scenarios. How are forces generated and sensed in vivo? Which molecular mechanisms are responsible for this mechanotransduction signal? Can we exploit exogenously applied forces to mimic and control this process? How can these extremely low forces be generated in vivo in a non-invasive manner? Can these methodologies for force generation be used in regenerative therapies? This review addresses these questions, providing a general overview of current knowledge on the applications of exogenous forces to manipulate axonal outgrowth, with a special focus on forces whose magnitude is similar to those generated in vivo. We also review the principal methodologies for applying these forces, providing new inspiration and insights into the potential of this approach for future regenerative therapies.

Wearable Fixation Device for a Magnetically Controllable Therapeutic Agent Carrier: Application to Cartilage Repair

Recently, significant research efforts have been devoted toward the development of magnetically controllable drug delivery systems, however, drug fixation after targeting remains a challenge hindering long-term therapeutic efficacy. To overcome this issue, we present a wearable therapeutic fixation device for fixing magnetically controllable therapeutic agent carriers (MCTACs) at defect sites and its application to cartilage repair using stem cell therapeutics. The developed device comprises an array of permanent magnets based on the Halbach array principle and a wearable band capable of wrapping the target body. The design of the permanent magnet array, in terms of the number of magnets and array configuration, was determined through univariate search optimization and 3D simulation. The device was fabricated for a given rat model and yielded a strong magnetic flux density (exceeding 40 mT) in the region of interest that was capable of fixing the MCTAC at the desired defect site. Through in-vitro and in-vivo experiments, we successfully demonstrated that MCTACs, both a stem cell spheroid and a micro-scaffold for cartilage repair, could be immobilized at defect sites. This research is expected to advance precise drug delivery technology based on MCTACs, enabling subject-specific routine life therapeutics. Further studies involving the proposed wearable fixation device will be conducted considering prognostics under actual clinical settings.

Conversion of haemodialysis patients from iron sucrose to iron isomaltoside: a real-world experience

Background

Anaemia is common in haemodialysis (HD) patients and associated with significant morbidity and mortality. Intravenous (IV) iron combined with erythropoiesis-stimulating agents (ESA) is the mainstay treatment of anaemia in these patients. The comparative efficacy and risk of adverse events with IV iron preparations have been assessed in only a few trials.

Methods

This was a retrospective observational study in 2 centres designed to compare the safety and efficacy of iron sucrose (IS-Venofer®) versus iron isomaltoside (IIM-Diafer®) in haemodialysis patients. The study included patients currently on dialysis and receiving Venofer who were switched to Diafer® and monitored for at least 12 months for each iron preparation.

Results

A total of 190 patients were included and had a mean age of 65.8 years (SD ± 15.5). Non-inferiority was confirmed with no change in mean haemoglobin per mg of iron administered over a 12-month period.

In total there were 41,295 prescriptions of iron isomaltoside and 14,685 of iron sucrose with no difference in the number of reported adverse events during the study period (7 each, none were severe).

There was a statistically significant effect on Hb over time after conversion, including adjustment for multiple comparisons. There were significant improvements in ferritin over time, which remained at 6 months (P < 0.01). The weekly iron dose was similar after adjustment (P = 0.02). The EPO dose did not differ significantly after month 0 in patients switched to IIM.

Conclusions

This study demonstrates the comparative safety and efficacy of iron isomaltoside versus iron sucrose, with similar dosing schedules in dialysis patients. Iron isomaltoside is non-inferior to iron sucrose in maintaining Hb in patients on regular haemodialysis/haemodiafiltration with no difference in the number of reported adverse events.

Clinical data for intravenous iron - debunking the hype around hypersensitivity

BACKGROUND

Reluctance to use intravenous (IV) iron for the treatment of iron deficiency continues due to a perceived high risk of severe hypersensitivity reactions (HSRs). Additionally, it has been hypothesized that 'dextran-derived' IV iron products (e.g., ferumoxytol [FER] and ferric derisomaltose/iron isomaltoside 1000 [FDI]) have a higher risk of severe HSRs than 'non-dextran-derived' products (e.g., ferric carboxymaltose [FCM] and iron sucrose [IS]). In the present analysis, HSR data from head-to-head randomized controlled trials (RCTs) with IV iron products were evaluated to determine if differences in safety signals are present among these IV iron formulations.

STUDY DESIGN AND METHODS

Reported serious or moderate-to-severe HSR incidence data from five RCTs (FIRM; FERWON-NEPHRO/-IDA; PHOSPHARE-IDA04/-IDA05) were used to calculate risk differences with 95% confidence intervals (CIs) for FER, FCM, FDI, and IS. The rates and risk differences for these HSRs were compared.

RESULTS

The analysis included data for 5247 patients: FER (n = 997), FCM (n = 1117), FDI (n = 2133) and IS (n = 1000). Overall rates of serious or moderate to severe HSRs were low (0.2%-1.7%). The risk differences (95% CIs) showed small differences between the IV iron formulations: FER versus FCM, -0.1 (-0.8 to 0.6); FDI versus IS, 0.1 (-0.3 to 0.5); FDI versus FCM, -0.9 (-3.7 to 1.9).

CONCLUSION

RCT evidence confirms a low risk of serious or moderate to severe HSRs with newer IV iron formulations and no significant differences among existing commercially available products. Thus, RCT data show that the supposed classification of dextran-derived versus non-dextran-derived IV iron products has no clinical relevance.

The Impact of Iron Supplementation for Treating Anemia in Patients with Chronic Kidney Disease: Results from Pairwise and Network Meta-Analyses of Randomized Controlled Trials

After relative erythropoietin deficiency, iron deficiency is the second most important contributing factor for anemia in chronic kidney disease (CKD) patients. Iron supplementation is a crucial part of the treatment of anemia in CKD patients, and intravenous (IV) iron supplementation is considered to be superior to per os (PO) iron supplementation. The differences between the available formulations are poorly characterized. This report presents results from pairwise and network meta-analyses carried out after a comprehensive search in sources of published and unpublished studies, according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) recommendations (International prospective register of systematic reviews PROSPERO reference ID: CRD42020148155). Meta-analytic calculations were performed for the outcome of non-response to iron supplementation (i.e., hemoglobin (Hgb) increase of <0.5–1.0 g/dL, or initiation/intensification of erythropoiesis-stimulating agent (ESA) therapy, or increase/change of iron supplement, or requirements of blood transfusion). A total of 34 randomized controlled trials (RCT) were identified, providing numerical data for analyses covering 93.7% (n = 10.097) of the total study population. At the network level, iron supplementation seems to have a more protective effect against the outcome of non-response before the start of dialysis than once dialysis is initiated, and some preparations seem to be more potent (e.g., ferumoxytol, ferric carboxymaltose), compared to the rest of iron supplements assessed (surface under the cumulative ranking area (SUCRA) > 0.8). This study provides parameters for adequately following-up patients requiring iron supplementation, by presenting the most performing preparations, and, indirectly, by making it possible to identify good responders among all patients treated with these medicines.

Intravenous iron: a framework for changing the management of iron deficiency

For decades intravenous iron was considered dangerous. Newer formulations with carbohydrate cores binding elemental iron more tightly allow complete iron replacement within 15-60 min in one visit. Meta-analyses and prospective comparisons of different formulations support equivalent safety to placebo with less toxicity than oral iron. Of the available formulations, the preponderance of published evidence supports equal safety and efficacy. In this Viewpoint, we report evidence supporting repositioning of intravenous iron to the frontline in multiple disorders with iron deficiency, which include heart failure, chronic kidney disease, inflammatory bowel disease, patient blood management in the perioperative period, and obstetrics and gynaecology. We have also highlighted neonatal evidence supporting the inadequacy of oral iron in late pregnancy, a critical period of iron need for normal foetal brain development. Physicians should consider prioritising the use of intravenous iron rather than oral iron as a treatment for iron deficiency in some of these clinical scenarios.

Anemia and iron deficiency in Crohn's disease

Introduction: Anemia is a common extraintestinal complication of Crohn's disease (CD) mainly caused by iron deficiency, that affects the quality of life in CD patients. Elucidation of the etiology and pathology of iron-deficiency anemia (IDA) and anemia of chronic diseases (ACD) has developed in recent years. Common biochemical parameters of iron status are insufficient for assessment of patients with anemia and CD. Thus, novel iron indices are required for accurate assessment in IDA patients with CD. Oral iron supplementation for IDA treatment is common and is associated with minor gastrointestinal side effects. Intravenous substitution improves safety profiles but may be not tolerable in some patients. Fortunately, additional therapies for anemia of active CD have emerged in recent years.Area covered: Here, we propose the review article on the link among anemia, iron deficiency, and Crohn's disease. We discuss the current diagnosis and therapy of anemia and iron deficiency in CD and propose the new directions for future research.Expert commentary: Exploring pathogeneses and treatments of anemia and iron deficiency in Crohn's disease will develop potential tools for early diagnosis and effective treatment of anemia in CD patients, and improve their life quality.

Initial experiences of an in-reach service providing iron infusions in residential aged care facilities

OBJECTIVE

To examine the feasibility of developing an in-reach parenteral iron infusion service to residents of residential aged care facilities (RACFs).

METHODS

An audit comparing the use of iron infusions in RACFs prior to and following the introduction of an in-reach iron infusion service.

RESULTS

Of the 738 inpatient iron infusions administered to inpatients ≥65 years in the 12 months prior to the in-reach service, 52 (7%) lived in an RACF, with no significant adverse events reported. After implementation of an in-reach service, a total of 37 RACF residents received parenteral iron in the first 12 months of the service, with no significant adverse events reported.

CONCLUSION

It is possible to safely provide parenteral iron through an in-reach service to residents in RACF. Further research is required to identify the person-level benefits achieved by this service.

Human adipose–derived mesenchymal stem cell–based medical microrobot system for knee cartilage regeneration in vivo

Targeted cell delivery by a magnetically actuated microrobot with a porous structure is a promising technique to enhance the low targeting efficiency of mesenchymal stem cell (MSC) in tissue regeneration. However, the relevant research performed to date is only in its proof-of-concept stage. To use the microrobot in a clinical stage, biocompatibility and biodegradation materials should be considered in the microrobot, and its efficacy needs to be verified using an in vivo model. In this study, we propose a human adipose–derived MSC–based medical microrobot system for knee cartilage regeneration and present an in vivo trial to verify the efficacy of the microrobot using the cartilage defect model. The microrobot system consists of a microrobot body capable of supporting MSCs, an electromagnetic actuation system for three-dimensional targeting of the microrobot, and a magnet for fixation of the microrobot to the damaged cartilage. Each component was designed and fabricated considering the accessibility of the patient and medical staff, as well as clinical safety. The efficacy of the microrobot system was then assessed in the cartilage defect model of rabbit knee with the aim to obtain clinical trial approval.

Cognitive-behavioural therapy for the management of inflammatory bowel disease-fatigue: a feasibility randomised controlled trial

Background

Fatigue is the third most prevalent symptom for patients with inflammatory bowel disease (IBD), yet optimal strategies for its management are unclear. Treatment protocols for fatigue in other conditions have been based on cognitive-behavioural models. Targeting cognitions, emotions and behaviour related to fatigue through cognitive-behavioural therapy (CBT) may be a viable option to improve fatigue and quality of life (QoL) in IBD.

Methods

This single centre, two-arm, feasibility randomised controlled trial (RCT) aimed to assess the feasibility and initial estimates of potential efficacy of a CBT intervention for the management of IBD-fatigue. Feasibility, acceptability and initial estimates of potential efficacy outcomes were collected through self-report measures and semi-structured interviews. Participants were recruited from one tertiary referral centre. Intervention Group 1 received a CBT manual for fatigue, one 60-min and seven 30-min telephone sessions with a therapist over 8-weeks. Control Group 2 received a fatigue information sheet without therapist support. A nested qualitative study evaluated patients’ and therapists’ experiences, and IBD-healthcare professionals’ (HCPs) perceptions of the intervention.

Results

Eighty-nine participants were assessed for eligibility. Of these, 31 of the 70 eligible participants consented to participate (recruitment rate of 44%). Of the 15 participants randomised to the intervention group, 13 (87%) started it and 10 (77% of those who started) completed all 8 sessions. Follow-up questionnaires were completed by 22 (71%) participants at 3 months, 14 (45%) at 6 months and 12 (39%) at 12 months’ follow-up. The intervention was acceptable to participants and feasible for therapists to deliver. HCPs reported that the intervention would be applicable, but time, finance and training constraints limit its implementation. Initial estimates of potential efficacy with complete case analysis showed a reduction in fatigue and an increase in QoL at 3, 6 and 12 months post-randomisation.

Conclusions

A full-scale effectiveness RCT testing CBT for IBD-fatigue is feasible and is potentially worthwhile with some changes to the protocol. However, given the small numbers, further pilot work is warranted before a full-scale RCT.

Trial registration

Registration Trial ISRCTN 17917944, Registered 2 September 2016

The safety and efficacy of ferumoxytol in the treatment of iron deficiency: a systematic review and meta-analysis

INTRODUCTION

Ferumoxytol is an intravenous (IV) iron formulation for treatment of iron deficiency (ID) that faced post-marketing reports of serious adverse events (SAEs).

OBJECTIVES

To determine the safety and efficacy of ferumoxytol compared to other iron formulations and placebo.

METHODS

We searched the Cochrane Library, Medline, and EMBASE from inception until February 2018 as well as trial registries and reference lists of relevant articles for randomized or quasi-randomized controlled trials.

RESULTS

The review included nine studies with 5691 participants. Studies were at low risk of bias. When comparing ferumoxytol to other IV iron formulations, there is moderate quality evidence (QE) of little to no difference in treatment emergent adverse events (TEAEs) (risk ratio [RR] 0.88, 95% confidence interval [CI] 0.80-0.97), treatment related adverse events (TRAEs) (RR 0.73, 95% CI 0.61-0.88), SAEs (RR 1.13, 95% CI 0.77-1.67), hypotension or hypersensitivity reactions (RR 0.58, 95% CI 0.31-1.09), or composite cardiovascular outcomes (RR 0.56, 95% CI 0.24-1.29), low QE of little to no difference in related SAEs (RR 0.55, 95% CI 0.05-6.16), and high QE of little to no difference in the number of patients with an increase in hemoglobin by at least 1 g/dL (RR 1.04, 95% CI 0.96-1.12). Ferumoxytol had less TEAEs compared to oral iron (RR 0.78, 95% CI 0.61-0.98), but more compared to placebo (RR 1.62, 95% CI 1.01-2.61).

DISCUSSION

Ferumoxytol is as efficacious and safe as alternative IV iron formulations with no clear safety concerns.

Pharmacokinetics of Ferumoxytol in the Abdomen and Pelvis: A Dosing Study with 1.5- and 3.0-T MRI Relaxometry

Background The off-label use of ferumoxytol (FE), an intravenous iron preparation for iron deficiency anemia, as a contrast agent for MRI is increasing; therefore, it is critical to understand its pharmacokinetics. Purpose To evaluate the pharmacokinetics of FE in the abdomen and pelvis, as assessed with quantitative 1.5- and 3.0-T MRI relaxometry. Materials and Methods R2*, an MRI technique used to estimate tissue iron content in the abdomen and pelvis, was performed at 1.5 and 3.0 T in 12 healthy volunteers between April 2015 and January 2016. Volunteers were randomly assigned to receive an FE dose of 2 mg per kilogram of body weight (FE_2mg) or 4 mg/kg (FE_4mg). MRI was repeated at 1.5 and 3.0 T for each volunteer at five time points: days 1, 2, 4, 7, and 30. A radiologist experienced in MRI relaxometry measured R2* in organs of the mononuclear phagocyte system (MPS) (ie, liver, spleen, and bone marrow), non-MPS anatomy (kidney, pancreas, and muscle), inguinal lymph nodes (LNs), and blood pool. A paired Student t test was used to compare changes in tissue R2*. Results Volunteers (six female; mean age, 44.3 years ± 12.2 [standard deviation]) received either FE_{2 mg} (n = 5) or FE_{4 mg} (n = 6). Overall R2* trend analysis was temporally significant (P < .001). Time to peak R2* in the MPS occurred on day 1 for FE_2mg and between days 1 and 4 for FE_4mg (P < .001 to P < .002). Time to peak R2* in non-MPS anatomy, LNs, and blood pool occurred on day 1 for both doses (P < .001 to P < .09). Except for the spleen (at 1.5 T) and liver, MPS R2* remained elevated through day 30 for both doses (P = .02 to P = .03). Except for the kidney and pancreas, non-MPS, LN, and blood pool R2* returned to baseline levels between days 2 and 4 at FE_2mg (P = .06 to P = .49) and between days 4 and 7 at FE_4mg (P = .06 to P = .63). There was no difference in R2* change between non-MPS and LN R2* at any time (range, 1-71 sec^-1 vs 0-50 sec^-1; P = .06 to P = .97). Conclusion The pharmacokinetics of ferumoxytol in lymph nodes are distinct from those in mononuclear phagocyte system (MPS) organs, parallel non-MPS anatomy, and the blood pool. © RSNA, 2019 Online supplemental material is available for this article.

Impact of Intravenous Iron on Oxidative Stress and Mitochondrial Function in Experimental Chronic Kidney Disease

Background: Mitochondrial dysfunction is observed in chronic kidney disease (CKD). Iron deficiency anaemia (IDA), a common complication in CKD, is associated with poor clinical outcomes affecting mitochondrial function and exacerbating oxidative stress. Intravenous (iv) iron, that is used to treat anaemia, may lead to acute systemic oxidative stress. This study evaluated the impact of iv iron on mitochondrial function and oxidative stress. Methods: Uraemia was induced surgically in male Sprague-Dawley rats and studies were carried out 12 weeks later in two groups sham operated and uraemic (5/6 nephrectomy) rats not exposed to i.v. iron versus sham operated and uraemic rats with iv iron. Results: Induction of uraemia resulted in reduced iron availability (serum iron: 31.1 ± 1.8 versus 46.4 ± 1.4 µM), low total iron binding capacity (26.4 ± 0.7 versus 29.5 ± 0.8 µM), anaemia (haematocrit: 42.5 ± 3.0 versus 55.0 ± 3.0%), cardiac hypertrophy, reduced systemic glutathione peroxidase activity (1.12 ± 0.11 versus 1.48 ± 0.12 U/mL), tissue oxidative stress (oxidised glutathione: 0.50 ± 0.03 versus 0.36 ± 0.04 nmol/mg of tissue), renal mitochondrial dysfunction (proton/electron leak: 61.8 ± 8.0 versus 22.7 ± 5.77) and complex I respiration (134.6 ± 31.4 versus 267.6 ± 26.4 pmol/min/µg). Iron therapy had no effect on renal function and cardiac hypertrophy but improved anaemia and systemic glutathione peroxidase (GPx) activity. There was increased renal iron content and complex II and complex IV dysfunction. Conclusion: Iron therapy improved iron deficiency anaemia in CKD without significant impact on renal function or oxidant status.

Pictorial review on abdominal applications of ferumoxytol in MR imaging

Though gadolinium-based contrast agents are the most widely used contrast media in MR for clinical use, problems with nephrogenic systemic fibrosis and tissue deposition render their safety debatable, at least in a selected patient population. Ferumoxytol has the potential to be used as an alternate contrast medium for various clinical applications across multiple organs. It has prolonged intravascular signal and delayed intracellular macrophage uptake which are unique properties compared to gadolinium-based agents. This pictorial review aims to review the current and potential clinical applications of ferumoxytol as a contrast agent in abdominal MR imaging.

Management of Iron Deficiency in Heart Failure

Anemia is a common finding in patients with heart failure (HF). The cause for anemia is multifactorial, with iron deficiency being the most common cause. Anemia with HF is an established predictor of morbidity and mortality. Iron deficiency in systolic HF, even without anemia, has been associated with increased mortality, increased hospitalizations, and decreased functional capacity and quality of life measures. Data from several randomized controlled trials and meta-analyses of iron deficiency and systolic HF show a beneficial effect for intravenous (IV) iron in terms of quality of life and functional capacity (improvements in 6-min walk test, and improvements in New York Heart Association functional class), as well as decreased hospitalizations for HF and reduction in cardiovascular mortality rates. Limited evidence exists for a beneficial effect of IV iron in diastolic dysfunction. Patients with symptomatic systolic HF should undergo an anemia diagnostic work-up. When iron deficiency (defined as ferritin <100 ng/mL or serum ferritin 100-299 ng/mL and transferrin saturation <20%) is present, current evidence supports treating HF patients with iron deficiency with IV iron.

Perinatal Iron Deficiency: Implications for Mothers and Infants

Iron deficiency, with or without anemia, is common in pregnant women. In fact, nearly 30% of reproductive-age women are anemic worldwide, and anemia in pregnancy has an estimated global prevalence of 38%. Severe anemia can substantially increase the risk of maternal mortality, and can adversely affect fetal development. In this review, we examine the available data regarding epidemiology and consequences of iron deficiency in mothers and infants, current treatment strategies, and make recommendations for screening and treatment of iron deficiency anemia in gravidas and neonates.

Ferumoxytol for the treatment of iron deficiency anemia

INTRODUCTION

Ferumoxytol is a superparamagnetic molecule originally developed as a contrast agent for magnetic resonance imaging. Elemental iron is contained within the carbohydrate core and is released slowly after infusion allowing a large dose of iron to be administered in a short period of time. Ferumoxytol, originally approved for iron deficiency in chronic kidney disease, received a broad label for any cause of iron deficiency after oral iron intolerance or in those circumstances when oral iron is ineffective or harmful. Areas covered: The chemistry, pharmacology and pharmacokinetics of ferumoxytol were reviewed. Retrospective, observational, and prospective phase II and III trials were reviewed. When appropriate, comparative safety and efficacy parameters were reported. Differentiation between minor infusion reactions and more severe hypersensitivity reactions that may lead to anaphylaxis is described. Expert commentary: Ferumoxytol is a safe and effective iron formulation providing a means of iron repletion in persons with iron deficiency with or without anemia. Relative to iron sucrose, ferric gluconate, and iron dextran and similar to ferric carboxymaltose and iron isomaltoside, ferumoxytol yields relatively low quantities of labile free iron. Hypersensitivity and anaphylaxis is extremely rare. Hypophosphatemia with ferumoxytol's administration is extremely rare. Optimal strategies for application of ferumoxytol-enhanced imaging and full replacement dosing in a single setting remain to be determined.

Health-related quality of life in patients with iron deficiency anemia: impact of treatment with intravenous iron

Most physicians appear to be aware of the health consequences of advanced anemia, especially in the acute setting, frequently responding with a not inconsequential therapeutic default of transfusion. In contrast, the profound impact that chronic anemia, of any degree, may have on a patient’s performance is underappreciated. The focus of this review is to 1) delineate the consistent and broad impact of anemia on patient quality of life as documented by multiple well-validated patient-reported outcome instruments and 2) demonstrate the essential normalization of the debilitation as assessed by these instruments following the administration of intravenous iron.

Biologically Targeted Magnetic Hyperthermia: Potential and Limitations

Hyperthermia, the mild elevation of temperature to 40–43°C, can induce cancer cell death and enhance the effects of radiotherapy and chemotherapy. However, achievement of its full potential as a clinically relevant treatment modality has been restricted by its inability to effectively and preferentially heat malignant cells. The limited spatial resolution may be circumvented by the intravenous administration of cancer-targeting magnetic nanoparticles that accumulate in the tumor, followed by the application of an alternating magnetic field to raise the temperature of the nanoparticles located in the tumor tissue. This targeted approach enables preferential heating of malignant cancer cells whilst sparing the surrounding normal tissue, potentially improving the effectiveness and safety of hyperthermia. Despite promising results in preclinical studies, there are numerous challenges that must be addressed before this technique can progress to the clinic. This review discusses these challenges and highlights the current understanding of targeted magnetic hyperthermia.

Safety of ferumoxytol in children undergoing cardiac MRI under general anaesthesia

BACKGROUND

Ferumoxytol, an "off-label" contrast agent, allows for better cardiac MRI quality as compared with gadolinium-based contrast agents. However, hypotension has been reported with the use of ferumoxytol for indications other than cardiac MRI. The purpose of our investigation was to evaluate the safety of ferumoxytol in children undergoing general anaesthesia for cardiac MRI.

METHODS

Medical records of children undergoing general anaesthesia for cardiac MRI were reviewed. Baseline demographic and medical characteristics, as well as imaging and anaesthetic duration and technique, were collected. The incidence of hypotension or other adverse events', need for vasoactive support, or airway intervention throughout the anaesthetic, was recorded.

RESULTS

A total of 95 patients were identified, 61 received ferumoxytol and 34 received gadolinium. There were no significant differences between groups with respect to age, weight, or baseline blood pressure. The incidence of low blood pressure - systolic or mean - after contrast administration did not differ between groups, and there was no difference in sustained hypotension or use of vasopressors between groups. One patient who received ferumoxytol had possible anaphylaxis. The image acquisition time (45 versus 68 min, p=0.002) and anaesthesia duration (100 versus 132 min, p=0.02) were shorter in the ferumoxytol group.

CONCLUSION

Transient low blood pressure was common in children undergoing cardiac MRI with anaesthesia, but the incidence of hypotension did not differ between ferumoxytol and gadolinium groups. The use of ferumoxytol was associated with significantly shorter scan time and anaesthesia duration, as well as a decreased need for airway intervention.

Bactericidal and immunomodulatory properties of magnetic nanoparticles functionalized by 1,4-dihydropyridines

Background

1,4-Dihydropyridine (1,4-DHP) and its derivatives are well-known calcium channel blockers with antiarrhythmic and antihypertensive activities. These compounds exhibit pleiotropic effects including antimicrobial activities that rely on their positive charge and amphipathic nature. Use of magnetic nanoparticles (MNPs) as carriers of 1,4-DHP modulates their properties and enables improved formulations with higher efficacy and less toxicity.

Methods

In this study, the antimicrobial and immunomodulatory activities of novel 1,4-DHP derivatives in free form and immobilized on MNPs were determined by evaluating pathogen outgrowth and proinflammatory cytokine release in experimental settings that involve incubation of various 1,4-DHPs with clinical isolates of bacteria or fungi as well as mammalian cell culture models.

Results

Conventional immobilization of 1,4-DHP on aminosilane-coated MNPs markedly enhances their antimicrobial activity compared to nonimmobilized molecules, in part because of the higher affinity of these nanosystems for bacterial cell wall components in the presence of human body fluids.

Conclusion

Optimized nanosystems are characterized by improved biocompatibility and higher anti-inflammatory properties that provide new opportunities for the therapy of infectious diseases.

Comparative safety of intravenous ferumoxytol versus ferric carboxymaltose in iron deficiency anemia: A randomized trial

Few trials have examined rates of hypersensitivity reactions (HSRs) with intravenous iron formulations used to treat iron deficiency anemia (IDA). This randomized, multicenter, double‐blind clinical trial compared the safety, and efficacy of ferumoxytol versus ferric carboxymaltose (FCM), focusing on rates of HSRs and hypotension as the primary end point. Patients with IDA of any etiology in whom oral iron was unsatisfactory or intolerable received ferumoxytol (n = 997) or FCM (n = 1000) intravenously over ≥15 minutes on days 1 and 8 or 9 for total respective doses of 1.02 g and 1.50 g. Composite incidences of moderate‐to‐severe HSRs, including anaphylaxis, or moderate‐to‐severe hypotension from baseline to week 5 (primary safety end point) were 0.6% and 0.7% in the ferumoxytol and FCM groups, respectively, with ferumoxytol noninferior to FCM. No anaphylaxis was reported in either group. The secondary safety end point of incidences of moderate‐to‐severe HSRs, including anaphylaxis, serious cardiovascular events, and death from baseline to week 5 were 1.3% and 2.0% in the ferumoxytol and FCM groups, respectively (noninferiority test P < .0001). Least‐squares mean changes in hemoglobin at week 5 were 1.4 g/dL and 1.6 g/dL in the ferumoxytol and FCM groups, respectively (noninferiority test P < .0001). Incidence of hypophosphatemia was 0.4% for ferumoxytol and 38.7% for FCM.

Advances in Magnetic Nanoparticles for Biomedical Applications

Magnetic nanoparticles (NPs) are emerging as an important class of biomedical functional nanomaterials in areas such as hyperthermia, drug release, tissue engineering, theranostic, and lab-on-a-chip, due to their exclusive chemical and physical properties. Although some works can be found reviewing the main application of magnetic NPs in the area of biomedical engineering, recent and intense progress on magnetic nanoparticle research, from synthesis to surface functionalization strategies, demands for a work that includes, summarizes, and debates current directions and ongoing advancements in this research field. Thus, the present work addresses the structure, synthesis, properties, and the incorporation of magnetic NPs in nanocomposites, highlighting the most relevant effects of the synthesis on the magnetic and structural properties of the magnetic NPs and how these effects limit their utilization in the biomedical area. Furthermore, this review next focuses on the application of magnetic NPs on the biomedical field. Finally, a discussion of the main challenges and an outlook of the future developments in the use of magnetic NPs for advanced biomedical applications are critically provided.

Ferumoxytol enhanced black-blood cardiovascular magnetic resonance imaging

BACKGROUND

Bright-blood and black-blood cardiovascular magnetic resonance (CMR) techniques are frequently employed together during a clinical exam because of their complementary features. While valuable, existing black-blood CMR approaches are flow dependent and prone to failure. We aim to assess the effectiveness and reliability of ferumoxytol enhanced (FE) Half-Fourier Single-shot Turbo Spin-echo (HASTE) imaging without magnetization preparation pulses to yield uniform intra-luminal blood signal suppression by comparing FE-HASTE with pre-ferumoxytol HASTE imaging.

METHODS

This study was IRB-approved and HIPAA compliant. Consecutive patients who were referred for FE-CMR between June 2013 and February 2017 were enrolled. Qualitative image scores reflecting the degree and reliability of blood signal suppression were based on a 3-point Likert scale, with 3 reflecting perfect suppression. For quantitative evaluation, homogeneity indices (defined as standard deviation of the left atrial signal intensity) and signal-to-noise ratios (SNR) for vascular lumens and cardiac chambers were measured.

RESULTS

Of the 340 unique patients who underwent FE-CMR, HASTE was performed in 257. Ninety-three patients had both pre-ferumoxytol HASTE and FE-HASTE, and were included in this analysis. Qualitative image scores reflecting the degree and reliability of blood signal suppression were significantly higher for FE-HASTE images (2.9 [IQR 2.8-3.0] vs 1.8 [IQR 1.6-2.1], p < 0.001). Inter-reader agreement was moderate (k = 0.50, 95% CI 0.45-0.55). Blood signal suppression was more complete on FE-HASTE images than on pre-ferumoxytol HASTE, as indicated by lower mean homogeneity indices (24.5 [IQR 18.0-32.8] vs 108.0 [IQR 65.0-170.4], p < 0.001) and lower blood pool SNR for all regions (5.6 [IQR 3.2-10.0] vs 21.5 [IQR 12.5-39.4], p < 0.001).

CONCLUSION

FE-HASTE black-blood imaging offers an effective, reliable, and simple approach for flow independent blood signal suppression. The technique holds promise as a fast and routine complement to bright-blood cardiovascular imaging with ferumoxytol.

Efficacy and safety of IV ferumoxytol for iron deficiency anemia in patients with cancer

Purpose

Iron deficiency anemia (IDA) is common in cancer patients due to blood loss and inflammation. Many do not tolerate oral iron or adequately respond. Intravenous (IV) iron is commonly used as an adjunct to erythropoiesis-stimulating agents; data on the use of IV iron monotherapy in these patients are limited. This study aimed to evaluate IV ferumoxytol for the treatment of cancer patients with IDA with a history of unsatisfactory oral iron therapy or in whom oral iron could not be used.

Patients and methods

This post hoc analysis of pooled data from two multicenter, randomized, controlled, Phase III trials evaluating IV ferumoxytol (510 mg ×2) vs placebo or iron sucrose (200 mg ×5) included a subgroup of 98 patients with cancer that the investigator identified as the primary cause of their IDA, or with cancer whose IDA was attributed to another comorbid condition (ferumoxytol, n=75; iron sucrose, n=13; placebo, n=10). Gastrointestinal cancers were most common (42), followed by breast (14), cervix (ten), and lung (nine). The primary endpoint was the mean change in hemoglobin (Hgb) from baseline to week 5.

Results

At week 5, both ferumoxytol and iron sucrose produced significant increases in Hgb from baseline (1.8 g/dL [P<0.0001] and 1.9 g/dL [P=0.002], respectively). During the studies, 45 patients received chemotherapy, 19 with platinum-based regimens. Erythropoiesis-stimulating agent doses were neither increased >20% nor initiated in any treatment group. Overall rates of adverse events and serious adverse events in the cancer subgroup mirrored those in the overall study population.

Conclusion

Monotherapy with IV iron appears to be an effective option for cancer patients with IDA who do not respond to or cannot tolerate oral iron therapy.

Comparative safety of intravenous Ferumoxytol versus Ferric Carboxymaltose for the Treatment of Iron Deficiency Anemia: rationale and study design of a randomized double-blind study with a focus on acute hypersensitivity reactions

Background

Intravenous (IV) iron is often used to treat iron deficiency anemia in patients who are unable to tolerate or are inadequately managed with oral iron. However, IV iron treatment has been associated with acute hypersensitivity reactions. The comparative risk of adverse events (AEs) with IV iron preparations has been assessed by a few randomized controlled trials, which are most often limited by small patient numbers, which lack statistical power to identify differences in low-frequency AE such as hypersensitivity reactions.

Materials and methods

Ferumoxytol versus Ferric Carboxymaltose for the Treatment of Iron Deficiency Anemia (FIRM) is a randomized, double-blind, international, multicenter, Phase III study designed to compare the safety of ferumoxytol and ferric carboxymaltose (FCM). The study includes adults with hemoglobin <12.0 g/dL (females) or <14.0 g/dL (males), transferrin saturation ≤20% or ferritin ≤100 ng/mL within 60 days of dosing, and a history of unsatisfactory or nontolerated oral iron therapy or in whom oral iron therapy is inappropriate. Patients are randomized (1:1) to ferumoxytol 510 mg or FCM 750 mg, each given intravenously on days 1 and 8. Primary end points are the incidence of moderate-to-severe hypersensitivity reactions, including anaphylaxis, and moderate-to-severe hypotension. All potential hypersensitivity and hypotensive reactions will be adjudicated by a blinded, independent Clinical Events Committee. A secondary safety end point is the composite frequency of moderate-to-severe hypersensitivity reactions, including anaphylaxis, serious cardiovascular events, and death. Secondary efficacy end points include mean change in hemoglobin and mean change in hemoglobin per milligram of iron administered from baseline to week 5. Urinary excretion of phosphorus and the occurrence of hypophosphatemia after IV iron administration will be examined as well as the mechanisms of such hypophosphatemia in a substudy.

Conclusion

FIRM will provide data on the comparative safety of ferumoxytol and FCM, two IV iron preparations with similar dosing schedules, focusing on moderate-to-severe hypersensitivity reactions, including anaphylaxis, and moderate-to-severe hypotension. The study plans to enroll 2000 patients and is expected to complete in 2017.

MRI monitoring of monocytes to detect immune stimulating treatment response in brain tumor

Background

Glioblastoma (GBM) is an aggressive brain cancer with a poor prognosis. The use of immune therapies to treat GBM has become a promising avenue of research. It was shown that amphotericin B (Amp B) can stimulate the innate immune system and suppress the growth of brain tumor initiating cells (BTICs). However, it is not feasible to use histopathology to determine immune activation in patients. We developed an MRI technique that can rapidly detect a therapeutic response in animals treated with drugs that stimulate innate immunity. Ultra-small iron oxide nanoparticles (USPIOs) are MRI contrast agents that have been widely used for cell tracking. We hypothesized that the increased monocyte infiltration into brain tumors due to Amp B can be detected using USPIO-MRI, providing an indicator of early drug response.

Methods

We implanted human BTICs into severe combined immunodeficient mice and allowed the tumor to establish before treating the animals with either Amp B or vehicle and then imaged them using MRI with USPIO (ferumoxytol) contrast.

Results

After 7 days of treatment, there was a significantly decreased T2* in the tumor of Amp B but not vehicle animals, suggesting that USPIO is carried into the tumor by monocytes. We validated our MRI results with histopathology and confirmed that Amp B-treated animals had significantly higher levels of macrophage/microglia that were colocalized with iron staining in their brain tumor compared with vehicle mice.

Conclusion

USPIO-MRI is a promising method of rapidly assessing the efficacy of anticancer drugs that stimulate innate immunity.

Ferumoxytol-enhanced magnetic resonance angiography for the assessment of potential kidney transplant recipients

Objectives

Traditional contrast-enhanced methods for scanning blood vessels using magnetic resonance imaging (MRI) or CT carry potential risks for patients with advanced kidney disease. Ferumoxytol is a superparamagnetic iron oxide nanoparticle preparation that has potential as an MRI contrast agent in assessing the vasculature.

Methods

Twenty patients with advanced kidney disease requiring aorto-iliac vascular imaging as part of pre-operative kidney transplant candidacy assessment underwent ferumoxytol-enhanced magnetic resonance angiography (FeMRA) between December 2015 and August 2016. All scans were performed for clinical indications where standard imaging techniques were deemed potentially harmful or inconclusive. Image quality was evaluated for both arterial and venous compartments.

Results

First-pass and steady-state FeMRA using incremental doses of up to 4 mg/kg body weight of ferumoxytol as intravenous contrast agent for vascular enhancement was performed. Good arterial and venous enhancements were achieved, and FeMRA was not limited by calcification in assessing the arterial lumen. The scans were diagnostic and all patients completed their studies without adverse events.

Conclusions

Our preliminary experience supports the feasibility and utility of FeMRA for vascular imaging in patients with advanced kidney disease due for transplant listing, which has the advantages of obtaining both arteriography and venography using a single test without nephrotoxicity.

Key Points

• Evaluation of vascular disease is important in planning kidney transplantation.

• Standard vascular imaging methods are often problematic in kidney disease patients.

• FeMRA has the advantage of arteriography and venography in a single test.

• FeMRA is safe and non-nephrotoxic.

• FeMRA is not limited by arterial calcification.

What Does the Boxed Warning Tell Us? Safe Practice of Using Ferumoxytol as an MRI Contrast Agent

BACKGROUND AND PURPOSE

Despite the label change and the FDA's boxed warning added to the Feraheme (ferumoxytol) label in March 2015, radiologists have shown increasing interest in using ferumoxytol as an MR imaging contrast agent as a supplement or alternative to gadolinium. The goals of this study were to provide information regarding ferumoxytol safety as an imaging agent in a single center and to assess how the Feraheme label change may affect this potential, currently off-label indication.

MATERIALS AND METHODS

This retrospective study evaluated the overall frequency of ferumoxytol-related adverse events when used for CNS MR imaging. Patients with various CNS pathologies were enrolled in institutional review board-approved imaging studies. Ferumoxytol was administered as multiple rapid bolus injections. The risk of adverse events was correlated with demographic data/medical history.

RESULTS

The safety of 671 ferumoxytol-enhanced MR studies in 331 patients was analyzed. No anaphylactic, life-threatening, or fatal (grade 4 or 5) adverse events were recorded. The overall proportion of ferumoxytol-related grade 1-3 adverse events was 10.6% (8.6% occurring within 48 hours), including hypertension (2.38%), nausea (1.64%), diarrhea (1.04%), and headache (1.04%). History of 1 or 2 allergies was associated with an increased risk of adverse events (14.61% versus 7.51% [no history]; P = .007).

CONCLUSIONS

The frequency of mild ferumoxytol-related adverse events was comparable with literature results, and no serious adverse event was recorded. Although the recommendations in the boxed warning should be followed, serious adverse events appear to be rare, and with proper precautions, ferumoxytol may be a valuable MR imaging agent.

Current and potential imaging applications of ferumoxytol for magnetic resonance imaging

Contrast-enhanced magnetic resonance imaging is a commonly used diagnostic tool. Compared with standard gadolinium-based contrast agents, ferumoxytol (Feraheme, AMAG Pharmaceuticals, Waltham, MA), used as an alternative contrast medium, is feasible in patients with impaired renal function. Other attractive imaging features of i.v. ferumoxytol include a prolonged blood pool phase and delayed intracellular uptake. With its unique pharmacologic, metabolic, and imaging properties, ferumoxytol may play a crucial role in future magnetic resonance imaging of the central nervous system, various organs outside the central nervous system, and the cardiovascular system. Preclinical and clinical studies have demonstrated the overall safety and effectiveness of this novel contrast agent, with rarely occurring anaphylactoid reactions. The purpose of this review is to describe the general and organ-specific properties of ferumoxytol, as well as the advantages and potential pitfalls associated with its use in magnetic resonance imaging. To more fully demonstrate the applications of ferumoxytol throughout the body, an imaging atlas was created and is available online as supplementary material.

Intravenous Ferumoxytol in Pediatric Patients With Iron Deficiency Anemia

Background: Iron deficiency anemia (IDA) is common in children. Limited data exist on the efficacy and safety of ferumoxytol in children. Objective: To assess the efficacy of 10 mg/kg dose given over 15-60 minutes in correcting IDA and report any adverse drug reactions (ADRs). Methods: We conducted a retrospective review of all patients who received ferumoxytol infusions for the management of IDA by the Pediatric Blood Management Program between October 2010 and March 2015. Results: A total of 110 infusions were given to 54 patients. Compared with baseline preinfusion hemoglobin (Hb; 9.2 ± 1.9 g/dL), a significant rise was seen at 1 week and 4 weeks postinfusion (11.5 ± 1.5 and 11.8 ± 1.7 g/dL, respectively, P < 0.001). Also, a significant rise in serum ferritin at 1 week and 4 weeks postinfusion was seen (51 ± 71 vs 192 ± 148 and 89 ± 135 ng/mL, P < 0.001 and <0.035, respectively). Patients who concomitantly received erythropoietin had a significantly larger Hb rise from baseline than those who did not at 4 weeks (2.7 ± 2.2 vs 1.6 ± 1.1 g/dL, P < 0.017). ADRs included pruritus (n = 1), urticaria (n = 1), and multisymptom episodes (n = 3) that included shortness of breath, chest tightness, back pain, and epigastric cramping that responded to therapy with IV diphenhydramine and methylprednisolone. Conclusion: Ferumoxytol was effective in treating IDA in our small study. Slow infusion rate and close monitoring allowed early detection of the infrequent ADRs.

Relative Incidence of Acute Adverse Events with Ferumoxytol Compared to Other Intravenous Iron Compounds: A Matched Cohort Study

Concerns persist about adverse reactions to intravenous (IV) iron. We aimed to determine the relative safety of ferumoxytol compared to other IV iron compounds. This retrospective cohort study with propensity-score matching for patients and drug doses used the Medicare 20% random sample to identify patients (1) without chronic kidney disease (non-CKD) and (2) with non-dialysis-dependent chronic kidney disease (NDD-CKD) who received a first dose of IV iron in 2010-2012. Exposures were ferumoxytol, iron sucrose, sodium ferric gluconate, or iron dextran. Outcomes were hypersensitivity symptoms, anaphylaxis, emergency department (ED) encounters, hospitalizations, and death after acute IV iron exposure. In the primary analysis for reactions on the day of or following exposure, there was no difference in hypersensitivity symptoms (hazard ratio 1.04, 95% confidence interval 0.94-1.16) or hypotension (0.83, 0.52-1.34) between 4289 non-CKD ferumoxytol users and an equal number of users of other compounds; results were similar for 7358 NDD-CKD patients and an equal number of controls. All-cause ED encounters or hospitalizations were less common in both the non-CKD (0.56, 0.45-0.70) and NDD-CKD ferumoxytol-treated patients (0.83, 0.71-0.95). Fewer than 10 deaths occurred in both the non-CKD and NDD-CKD ferumoxytol users and in matched controls; the hazard for death did not differ significantly between ferumoxytol users and controls in the non-CKD patients (2.00, 0.33-11.97) or in the NDD-CKD patients (0.25, 0.04-1.52). Multiple sensitivity analyses showed similar results. Ferumoxytol did not appear to be associated with more adverse reactions than other compounds for the treatment of iron-deficiency anemia in both non-CKD and NDD-CKD patients.

Magnetic nanoparticles for precision oncology: theranostic magnetic iron oxide nanoparticles for image-guided and targeted cancer therapy

Recent advances in the development of magnetic nanoparticles (MNPs) have shown promise in the development of new personalized therapeutic approaches for clinical management of cancer patients. The unique physicochemical properties of MNPs endow them with novel multifunctional capabilities for imaging, drug delivery and therapy, which are referred to as theranostics. To facilitate the translation of those theranostic MNPs into clinical applications, extensive efforts have been made on designing and improving biocompatibility, stability, safety, drug-loading ability, targeted delivery, imaging signal and thermal- or photodynamic response. In this review, we provide an overview of the physicochemical properties, toxicity and theranostic applications of MNPs with a focus on magnetic iron oxide nanoparticles.