Management of serum phosphorus over a 1-year follow-up in patients on peritoneal dialysis prescribed sucroferric oxyhydroxide as part of routine care: a retrospective analysis.

BACKGROUND: Hyperphosphatemia is associated with increased morbidity and mortality in patients with end-stage kidney disease (ESKD). Whereas clinical and observational studies have demonstrated the effectiveness of sucroferric oxyhydroxide (SO) in controlling serum phosphorus (sP) in ESKD, data on the real-world impact of switching to SO in patients on peritoneal dialysis (PD) are limited. In this retrospective database analysis, we examine the impact of SO on sP management over a 1-year period among PD patients prescribed SO as part of routine clinical care. METHODS: We analyzed de-identified data from adults on PD in Fresenius Kidney Care clinics who were prescribed SO monotherapy between May 2018 and December 2019 as part of routine clinical management. Changes from baseline in sP levels, phosphate binder (PB) pill burden, and laboratory parameters were evaluated during the four consecutive 91-day intervals of SO treatment. RESULTS: The mean age of the 402 patients who completed 1 year of SO was 55.2 years at baseline, and they had been on PD for an average of 19.9 months. SO was initiated with no baseline PB recorded in 36.1% of patients, whereas the remaining 257 patients were switched to SO from sevelamer (39.7%), calcium acetate (30.4%), lanthanum (1.2%), ferric citrate (14.0%), or more than one PB (14.8%). Mean sP at baseline was 6.26 mg/dL. After being prescribed SO, the percentage of patients achieving sP ≤ 5.5 mg/dL increased from 32.1% (baseline) to 46.5-54.0% during the 1-year follow-up, whereas the mean number of PB pills taken per day decreased from 7.7 at baseline (among patients on a baseline PB) to 4.6 to 5.4. Serum phosphorus and PB pill burden decreased regardless of changes in residual kidney function over the 12-month period. Similar results were observed for the full cohort (976 patients who either completed or discontinued SO during the 1-year follow-up). CONCLUSIONS: Patients on PD who were prescribed SO as part of routine care for phosphorus management experienced significant reductions in SP and PB pills per day and improvements in sP target achievement, suggesting the effectiveness of SO on SP management with a concurrent reduction in pill burden.

Hyaluronic acid as a pulpotomy material in primary molars: an up to 30 months retrospective study.

BACKGROUND: The aim of this retrospective study was to determine the long-term clinical and radiographic success of our previous randomized clinical trial and to compare the success of hyaluronic acid, with the widely used formocresol and ferric sulphate agents. METHODS: This retrospective study is the extension of the 1-year survey of our randomized clinical trial that had compared the effectiveness of a hyaluronic acid pulpotomy over formocresol and ferric sulphate pulpotomies and included clinical and radiographic evaluations with a follow-up period of over 24 months for 44 children who applied to our clinic between May 2019 and September 2019. Long-term clinical and radiographic data were obtained from the periodic files of our department, wherein each tooth's file was examined to identify any clinical and radiographic findings. Descriptive statistics and Pearson's chi-square tests were used to evaluate the data. Statistical significance was considered as p < 0.05. RESULTS: The clinical and radiographic success rates of the hyaluronic acid, formocresol, and ferric sulphate groups were not statistically different at > 24 months. None of the teeth in the hyaluronic acid group showed any clinical findings at > 24 months. CONCLUSIONS: Hyaluronic acid pulpotomies exhibited comparable success rates to formocresol and ferric sulphate materials spanning over 24 months examinations. Because of convenient accessibility and applicability of hyaluronic acid, it may be recommended as a promising alternative medicament for pulpotomy treatments of primary molars. However, further long-term follow-up human studies are needed to better understand the effect of hyaluronic acid on the dental pulp of human primary molars.

A meta-analysis of ferric carboxymaltose versus other intravenous iron preparations for the management of iron deficiency anemia during pregnancy.

Objective: We conducted a meta-analysis of randomized clinical trials evaluating the clinical effects of ferric carboxymaltose therapy compared to other intravenous iron in improving hemoglobin and serum ferritin in pregnant women. We also assessed the safety of ferric carboxymaltose vs. other intravenous iron. Data source: EMBASE, PubMed, and Web of Science were searched for trials related to ferric carboxymaltose in pregnant women, published between 2005 and 2021. We also reviewed articles from google scholar. The keywords "ferric carboxymaltose," "FCM," "intravenous," "randomized," "pregnancy," "quality of life," and "neonatal outcomes" were used to search the literature. The search was limited to pregnant women. Selection of studies: Studies related to ferric carboxymaltose in pregnancy were scanned. Observational studies, review articles, and case reports were excluded. Randomized studies in pregnant women involving ferric carboxymaltose and other intravenous iron formulations were shortlisted. Of 256 studies, nine randomized control trials were selected. Data collection: Two reviewers independently extracted data from nine selected trials. Data synthesis: The final effect size for increase in hemoglobin after treatment was significant for ferric carboxymaltose vs. iron sucrose/iron polymaltose (standard mean difference 0.89g/dl [95% confidence interval 0.27,1.51]). The final effect size for the increase in ferritin after treatment was more for ferric carboxymaltose vs. iron sucrose/iron polymaltose (standard mean difference 22.53µg/L [-7.26, 52.33]). No serious adverse events were reported with ferric carboxymaltose or other intravenous iron. Conclusion: Ferric carboxymaltose demonstrated better efficacy than other intravenous iron in increasing hemoglobin and ferritin levels in treating iron deficiency anemia in pregnant women.

Efficacy of ferric carboxymaltose on haemoglobin response among older patients with gastrointestinal bleeding: a randomised clinical trial.

BACKGROUND: Acute gastrointestinal bleeding (AGIB) is common in older patients but the use of iron in this context remains understudied. AIMS: This study aimed to evaluate prospectively the efficacy of ferric carboxymaltose to treat anaemia in older patients after AGIB. METHODS: This randomised double-blinded placebo-controlled clinical trial was conducted in 10 French centres. Eligible patients were 65 years or more, had controlled upper or lower gastrointestinal bleeding and a haemoglobin level of 9-11 g/dl. Patients were randomly assigned, in a 1:1 ratio, to receive either one intravenous iron injection of ferric carboxymaltose or one injection of saline solution. The primary endpoint was the difference in haemoglobin level between day 0 and day 42. Secondary endpoints were treatment-emergent adverse events, serious adverse events, rehospitalisation and improvement of quality of life (QOL) at day 180. RESULTS: From January 2013 to January 2017, 59 patients were included. The median age of patients was 81.9 [75.8, 87.3] years. At day 42, a significant difference in haemoglobin level increase was observed (2.49 g/dl in the ferric carboxymaltose group vs. 1.56 g/dl in the placebo group, P = 0.02). At day 180, QOL, measured on European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30, improved by 10.5 points in the ferric carboxymaltose group and by 8.2 points in the placebo group (P = 0.56). Rates of adverse events and rehospitalisation were similar in the two groups. CONCLUSIONS: Intravenous iron seems safe and effective to treat anaemia in older patients after AGIB and should be considered as a standard-of-care treatment. ClinicalTrials.gov (NCT01690585).

[Evaluation of the efficacy and safety of intravenous infusion of ferric derisomaltose in the treatment of iron deficiency anemia: a single-center retrospective analysis].

Objective: To investigate the clinical efficacy and safety of ferric derisomaltose injection versus iron sucrose injection in the treatment of iron deficiency anemia (IDA) . Methods: A total of 120 patients with iron deficiency anemia admitted from June 2021 to March 2023 were given intravenous iron supplementation with ferric derisomaltose to assess the efficacy and safety of hemoglobin (HGB) elevation before and after treatment. Simultaneously, the clinical effects of iron supplementation with iron sucrose were compared to those of inpatient patients during the same period. Results: Baseline values were comparable in both groups. Within 12 weeks of treatment, the elevated HGB level in the ferric derisomaltose group was higher than that of the iron sucrose group, with a statistical difference at all time points, and the proportion of HGB increased over 20 g/L in the patients treated for 4 weeks was higher (98.7%, 75.9% ). During the treatment with ferric derisomaltose and iron sucrose, the proportion of mild adverse reactions in the ferric derisomaltose group was slightly lower than that of the iron sucrose group, and neither group experienced any serious adverse reactions. The patients responded well to the infusion treatment, with no reports of pain or pigmentation at the injection site. Conclusion: The treatment of IDA patients with ferric derisomaltose has a satisfactory curative effect, with the advantages of rapidity, accuracy, and safety. Therefore, it is worthy of widespread clinical use.

Comparative Efficacy of Ferrous, Ferric and Liposomal Iron Preparations for Prophylaxis in Infants.

OBJECTIVE: This study aimed to assess the efficacy of different oral iron preparations prescribed for prevention of iron deficiency anemia in healthy infants. METHODS: This retrospective study enrolled infants aged between 6 and 12 months who were initiated on iron prophylaxis at four months of age. Enrolled children consistently used specific iron preparations (ferrous, ferric or liposomal iron) and had their complete blood counts and serum ferritin levels assessed within the 6-12 month timeframe. Blood values and iron prophylaxis type (ferrous (Fe+2), ferric (Fe+3), liposomal iron) were recorded. Chi-square test was used to compare the hemoglobin and ferritin levels levels between groups. Univariate and multivariate regression analyses assessed the risk of anemia. RESULTS: The study included 371 children (ferrous sulphate - 60, iron hydroxide-polymaltose complex - 137 and liposomal ferric pyrophosphate - 174) with a mean (SD) age 9.1 (1.3) mo. Iron deficiency in different groups were: liposomal iron (46.0%), ferric iron (44.5%), and ferrous iron (5.0%). Mean (SD) serum ferritin levels (µg/L) were higher in the ferrous group [30.1 (10.8)] compared to infants receiving ferric [17.6 (14.50)] and liposomal iron [15.4 (12.1)] (P < 0.001). Mean (SD) hemoglobin levels (g/dL) were significantly higher in the ferrous group [12.4 (0.8)] compared to ferric [11.9 (1.1)] and liposomal iron group [12.0 (1.1)]; P =0.008. Multiple regression analysis showed that ferrous group was associated with a lower risk of iron deficiency [OR (95% CI) 0.04 (0.01-0.15), P < 0.001]. CONCLUSION: Ferrous iron demonstrated superior efficacy compared to ferric and liposomal iron. Further studies are needed to establish alternative iron preprations in children.

Clinical efficacy and safety of intravenous ferric carboxymaltose for treatment of restless legs syndrome: a multicenter, randomized, placebo-controlled clinical trial.

STUDY OBJECTIVES: Iron therapy is associated with improvements in restless legs syndrome (RLS). This multicenter, randomized, double-blind study evaluated the effect of intravenous ferric carboxymaltose (FCM) on RLS. METHODS: A total of 209 adult patients with a baseline International RLS (IRLS) score ≥ 15 were randomized (1:1) to FCM (750 mg/15 mL) or placebo on study days 0 and 5. Ongoing RLS medication was tapered starting on Day 5, with the goal of discontinuing treatment or achieving the lowest effective dose. Co-primary efficacy endpoints were changed from baseline in IRLS total score and the proportion of patients rated as much/very much improved on the Clinical Global Impression (CGI)-investigator (CGI-I) scale at day 42 in the "As-Treated" population. RESULTS: The "As-Treated" population comprised 107 FCM and 101 placebo recipients; 88 (82.2%) and 68 (67.3%), respectively, completed the day 42 assessment. The IRLS score reduction was significantly greater with FCM versus placebo: least-squares mean (95% confidence interval [CI]) -8.0 (-9.5, -6.4) versus -4.8 (-6.4, -3.1); p = .0036. No significant difference was observed in the proportion of FCM (35.5%) and placebo (28.7%) recipients with a CGI-I response (odds ratio 1.37 [95% CI: 0.76, 2.47]; p = .2987). Fewer patients treated with FCM (32.7%) than placebo (59.4%) received RLS interventions between day 5 and study end (p = .0002). FCM was well tolerated. CONCLUSIONS: The IRLS score improved with intravenous FCM versus placebo, although the combination of both co-primary endpoints was not met. Potential methodological problems in the study design are discussed.

Intravenous iron for heart failure, iron deficiency definitions, and clinical response: the IRONMAN trial.

BACKGROUND AND AIMS: What is the relationship between blood tests for iron deficiency, including anaemia, and the response to intravenous iron in patients with heart failure? METHODS: In the IRONMAN trial, 1137 patients with heart failure, ejection fraction ≤ 45%, and either serum ferritin < 100 µg/L or transferrin saturation (TSAT) < 20% were randomized to intravenous ferric derisomaltose (FDI) or usual care. Relationships were investigated between baseline anaemia severity, ferritin and TSAT, to changes in haemoglobin from baseline to 4 months, Minnesota Living with Heart Failure (MLwHF) score and 6-minute walk distance achieved at 4 months, and clinical events, including heart failure hospitalization (recurrent) or cardiovascular death. RESULTS: The rise in haemoglobin after administering FDI, adjusted for usual care, was greater for lower baseline TSAT (Pinteraction < .0001) and ferritin (Pinteraction = .028) and more severe anaemia (Pinteraction = .014). MLwHF scores at 4 months were somewhat lower (better) with FDI for more anaemic patients (overall Pinteraction = .14; physical Pinteraction = .085; emotional Pinteraction = .043) but were not related to baseline TSAT or ferritin. Blood tests did not predict difference in achieved walking distance for those randomized to FDI compared to control. The absence of anaemia or a TSAT ≥ 20% was associated with lower event rates and little evidence of benefit from FDI. More severe anaemia or TSAT < 20%, especially when ferritin was ≥100 µg/L, was associated with higher event rates and greater absolute reductions in events with FDI, albeit not statistically significant. CONCLUSIONS: This hypothesis-generating analysis suggests that anaemia or TSAT < 20% with ferritin > 100 µg/L might identify patients with heart failure who obtain greater benefit from intravenous iron. This interpretation requires confirmation.

Advances in Atherosclerosis Theranostics Harnessing Iron Oxide-Based Nanoparticles.

Atherosclerosis, a multifaceted chronic inflammatory disease, has a profound impact on cardiovascular health. However, the critical limitations of atherosclerosis management include the delayed detection of advanced stages, the intricate assessment of plaque stability, and the absence of efficacious therapeutic strategies. Nanotheranostic based on nanotechnology offers a novel paradigm for addressing these challenges by amalgamating advanced imaging capabilities with targeted therapeutic interventions. Meanwhile, iron oxide nanoparticles have emerged as compelling candidates for theranostic applications in atherosclerosis due to their magnetic resonance imaging capability and biosafety. This review delineates the current state and prospects of iron oxide nanoparticle-based nanotheranostics in the realm of atherosclerosis, including pivotal aspects of atherosclerosis development, the pertinent targeting strategies involved in disease pathogenesis, and the diagnostic and therapeutic roles of iron oxide nanoparticles. Furthermore, this review provides a comprehensive overview of theranostic nanomedicine approaches employing iron oxide nanoparticles, encompassing chemical therapy, physical stimulation therapy, and biological therapy. Finally, this review proposes and discusses the challenges and prospects associated with translating these innovative strategies into clinically viable anti-atherosclerosis interventions. In conclusion, this review offers new insights into the future of atherosclerosis theranostic, showcasing the remarkable potential of iron oxide-based nanoparticles as versatile tools in the battle against atherosclerosis.

Effect of ferric citrate hydrate on fibroblast growth factor 23 and platelets in non-dialysis-dependent chronic kidney disease and non-chronic kidney disease patients with iron deficiency anemia.

BACKGROUND: Iron deficiency anemia (IDA) increases levels of C-terminal fibroblast growth factor 23 (cFGF23) and platelet count (PLT), each of which is associated with cardiovascular events. Therefore, we hypothesized that iron replacement with ferric citrate hydrate (FC) would decrease cFGF23 levels and PLT in patients with IDA. METHODS: In a randomized, open-label, multicenter, 24-week clinical trial, patients with non-dialysis-dependent chronic kidney disease (CKD) and non-CKD complicated by IDA (8.0 ≤ hemoglobin < 11.0 g/dL; and serum ferritin < 50 ng/mL [CKD]; < 12 ng/mL [non-CKD]) were randomized 1:1 to FC-low (500 mg: approximately 120 mg elemental iron/day) or FC-high (1000 mg: approximately 240 mg elemental iron/day). If sufficient iron replacement had been achieved after week 8, further treatment was discontinued. RESULTS: Seventy-three patients were allocated to FC-low (CKD n = 21, non-CKD n = 15) and FC-high (CKD n = 21, non-CKD n = 16). Regardless of CKD status, FC increased serum ferritin and transferrin saturation, did not change intact FGF23 or serum phosphorus, but decreased cFGF23. In FC-low group, median changes in cFGF23 from baseline to week 8 were -58.00 RU/mL in CKD and -725.00 RU/mL in non-CKD; in FC-high group, the median changes were -66.00 RU/mL in CKD and -649.50 RU/mL in non-CKD. By week 8, FC treatment normalized PLT in all patients with high PLT at baseline (>35.2 × 104/µL; FC-low: 1 CKD, 8 non-CKD; FC-high: 3 CKD, 8 non-CKD). CONCLUSION: Regardless of CKD status, iron replacement with FC decreased elevated cFGF23 levels and normalized elevated PLT in patients with IDA. CLINICAL TRIAL REGISTRATION NUMBER: jRCT2080223943.

Early improvement of global longitudinal strain after iron deficiency correction in heart failure with reduced ejection fraction.

BACKGROUND: Iron deficiency correction with ferric carboxymaltose improves symptoms and reduces rehospitalization in patients with reduced left ventricular ejection fraction. The mechanisms underlying these improvements are poorly understood. This study aimed to determine changes in left ventricular contractility after iron treatment as reflected in global longitudinal strain. METHODS: Prospective single-center study including 43 adults with reduced ejection fraction, non-anemic iron deficiency, and functional class II-III heart failure despite optimal medical treatment. Global longitudinal strain through speckle-tracking echocardiography was measured at baseline and 4 weeks after ferric carboxymaltose. RESULTS: A significant improvement in global longitudinal strain was detected (from -12.3% ± 4.0% at baseline to -15.6% ± 4.1%, p < .001); ferritin and transferrin saturation index had increased, but ejection fraction presented no significant changes (baseline 35.7% ± 4.6%, follow-up 37.2% ± 6.6%, p = .073). CONCLUSIONS: In patients with heart failure and reduced ejection fraction, the correction of iron deficiency with ferric carboxymaltose is associated with an early improvement in global longitudinal strain, possibly suggesting a direct effect of iron correction on myocardial contractility.

Serum Phosphorus Management with Sucroferric Oxyhydroxide as a First-Line Phosphate Binder within the First Year of Hemodialysis.

INTRODUCTION: Sucroferric oxyhydroxide (SO), a non-calcium, chewable, iron-based phosphate binder (PB), effectively lowers serum phosphorus (sP) concentrations while reducing pill burden relative to other PBs. To date, SO studies have largely examined treatment-experienced, prevalent hemodialysis populations. We aimed to explore the role of first-line SO initiated during the first year of dialysis. METHODS: We retrospectively analyzed deidentified data from adults receiving in-center hemodialysis who were prescribed SO monotherapy within the first year of hemodialysis as part of routine clinical care. All patients continuing SO monotherapy for 12 months were included. Changes from baseline in sP, achievement of sP ≤5.5 and ≤4.5 mg/dL, and other laboratory parameters were analyzed quarterly for 1 year. RESULTS: The overall cohort included 596 patients, 286 of whom had a dialysis vintage ≤3 months. In the 3 months preceding SO initiation, sP rapidly increased (mean increases of 1.02 and 1.65 mg/dL in the overall cohort and incident cohort, respectively). SO treatment was associated with significant decreases in quarterly sP (mean decreases of 0.26-0.36; p < 0.0001 for each quarter and overall). While receiving SO, 55-60% of patients achieved sP ≤5.5 mg/dL and 21-24% achieved sP ≤4.5 mg/dL (p < 0.0001 for each quarter and overall vs. baseline). Daily PB pill burden was approximately 4 pills. Serum calcium concentrations increased and intact parathyroid hormone concentrations decreased during SO treatment (p < 0.0001 vs. baseline). CONCLUSIONS: Among patients on hemodialysis, initiating SO as a first-line PB resulted in significant reductions in sP while maintaining a relatively low PB pill burden.

Effect of Ziltivekimab on Determinants of Hemoglobin in Patients with CKD Stage 3-5: An Analysis of a Randomized Trial (RESCUE).

SIGNIFICANCE STATEMENT: Systemic inflammation in CKD can lead to anemia. Ziltivekimab, a fully human monoclonal antibody targeting the IL-6 ligand, has been shown to reduce systemic inflammation in patients with CKD. It has also been shown to increase serum albumin in patients on hemodialysis with inflammation and hyporesponsiveness to treatment with erythropoiesis-stimulating agents. This exploratory analysis of the RESCUE clinical trial found that among patients with CKD stage 3-5 and systemic inflammation, ziltivekimab treatment significantly increased hemoglobin (Hb) levels after 12 weeks compared with placebo. Ziltivekimab was also associated with significant increases in serum iron levels, total iron-binding capacity, and transferrin saturation. No major safety concerns were reported. Further clinical trials are warranted to study ziltivekimab's potential for anemia management in patients with CKD. BACKGROUND: In the phase 2 RESCUE clinical trial, ziltivekimab, a fully human monoclonal antibody against the IL-6 ligand, significantly reduced the biomarkers of inflammation compared with placebo, in patients with CKD and systemic inflammation (high-sensitivity C-reactive protein ≥2 mg/L). The aim of this subanalysis of RESCUE trial data was to assess the effect of ziltivekimab on Hb and iron homeostasis in this patient population. METHODS: This was an analysis of exploratory end points from the RESCUE trial ( NCT03926117 ), which included 264 adults with CKD stage 3-5 and high-sensitivity C-reactive protein ≥2 mg/L. Participants received placebo or subcutaneous ziltivekimab (7.5, 15, or 30 mg) (1:1:1:1) once every 4 weeks, up to 24 weeks. End points for this analysis were changes in Hb and biomarkers of iron homeostasis from baseline to week 12. RESULTS: The trial was terminated early due to the coronavirus disease 2019 pandemic, and thus, data up to week 12 are presented. Hb levels significantly increased from baseline to week 12 with ziltivekimab 7.5, 15, and 30 mg (treatment differences versus placebo: +0.57 g/dl [95% confidence interval, 0.27 to 0.86], +1.05 g/dl [0.76 to 1.33], and +0.99 g/dl [0.70 to 1.28], respectively, all P < 0.001). Ziltivekimab was associated with significant increases in serum iron levels, total iron-binding capacity, and transferrin saturation from baseline to week 12 ( P < 0.05 versus placebo for all doses and comparisons). Cases of sustained thrombocytopenia, sustained neutropenia, anemia, and iron deficiency anemia were infrequent and similar across all groups. CONCLUSIONS: Anti-inflammatory therapy with ziltivekimab improved the markers of anemia and iron homeostasis in people with stage 3-5 CKD and systemic inflammation, suggesting a possible role in anemia management.

Seven-Year Single-Center Experience of the Efficacy and Safety of Ferric Carboxymaltose in Cancer Patients with Iron-Deficiency Anemia.

Anemia remains an essential concern affecting the quality of life and the survival of cancer patients. Although there are different approaches to treating anemia in cancer patients, the number of studies reporting the efficacy of iron replacement in cancer patients is limited. In this study, the efficacy and safety of iron carboxymaltose, a parenteral iron treatment option, in the treatment of anemia, were examined retrospectively. A total of 1102 adult patients who received IV ferric carboxymaltose treatment at Hacettepe Oncology Hospital between 2014 and 2020 were included. The mean hemoglobin change observed at the end of the 12th week was 1.8 g/dL, and the rate of patients with an increase in hemoglobin of 1 g/dL or more was 72.1%. It was observed that the treatment demonstrated effectiveness in patients receiving active cancer treatment in all tumor types. The treatment was generally safe, and no grade 3-5 side effects were observed in the patients included in the study. According to one of the most extensive series published in the literature, iron carboxymaltose is an efficient and safe alternative for cancer patients with iron-deficiency anemia.

Biodistribution and histological analysis of iron oxide-dextran nanoparticles in wistar rats.

Iron oxide nanoparticles (IONP) are showing promise in many biomedical applications. One of these- magnetic hyperthermia- utilizes externally applied alternating magnetic fields and tumor-residing magnetic nanoparticles to generate localized therapeutic temperature elevations. Magnetic hyperthermia is approved in Europe to treat glioblastoma and is undergoing clinical assessment in the United States to treat prostate cancer. In this study, we performed biodistribution and histological analysis of a new IONP (RCL-01) in Wistar rats. These nanoparticles are currently undergoing clinical assessment in locally advanced pancreatic ductal adenocarcinoma to determine the feasibility of magnetic hyperthermia treatment in this disease. The study presented here aimed to determine the fate of these nanoparticles in vivo and whether this results in organ damage. Wistar rats were injected intravenously with relatively high doses of IONP (30 mgFe/kg, 45 mgFe/kg and 60 mgFe/kg) and compared to a vehicle control to determine the accumulation of iron in organs and whether this resulted in histological changes in these tissues. Dose-dependent increases of iron were observed in the liver, spleen and lungs of IONP-treated animals at 7 days postinjection; however, this did not result in significant histological changes in these tissues. Immunofluorescent imaging determined these nanoparticles are internalized by macrophages in tissue, suggesting they are readily phagocytosed by the reticuloendothelial system for eventual recycling. Notably, no changes in iron or dextran staining were found in the kidneys across all treatment groups, providing evidence for potential renal clearance.