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Iron chelators have been widely used to remove excess toxic iron from patients with secondary iron overload. However, small molecule-based iron chelators can cause adverse side effects such as infection, gastrointestinal bleeding, kidney failure, and liver fibrosis. Here we report renal clearable nanochelators for iron overload disorders. First, after a singledose intravenous injection, the nanochelator shows favorable pharmacokinetic properties, such as kidney-specific biodistribution and rapid renal excretion (>80% injected dose in 4 h), compared to native deferoxamine (DFO). Second, subcutaneous (SC) administration of nanochelators improves pharmacodynamics, as evidenced by a 7-fold increase in efficiency of urinary iron excretion compared to intravenous injection. Third, daily SC injections of the nanochelator for 5 days to iron overload mice and rats decrease iron levels in serum and liver. Furthermore, the nanochelator significantly reduces kidney damage caused by iron overload without demonstrating DFO’s own nephrotoxicity. This renal clearable nanochelator provides enhanced efficacy and safety. The build-up of iron in the body can have serious consequences; current treatment therapies suffer from adverse side effects and toxicity. Here, the authors developed renal clearable nanochelators with improved pharmacodynamics and demonstrated their efficacy and safety in iron overload animal models.

To avoid the biotoxicity and poor bioavailability of deferoxamine mesylate (DFO), an iron chelation for the treatment of Parkinson's disease (PD), a self-oriented DFO nanoparticle functionalized with Exendin-4 was developed, which can be targeted delivered into the lesion brain area to achieve synergistic effects against PD by iron chelation and inflammatory suppression. The self-oriented DFO nanoparticles (Ex-4@DFO NPs) were synthesized by double emulsion technique, and characterized in terms of the particle size, morphology and DFO encapsulation efficiency. The cellular internalization, biocompatibility and cytoprotection of NPs were assessed on BV-2 and SH-SY5Y cells. The brain targeting and therapeutic effect of NPs were investigated in MPTP-induced PD mice by near-infrared II fluorescence imaging and immunofluorescence staining, as well as mobility behavioral tests. Ex-4@DFO NPs with a particle size of about 100 nm, showed great biocompatibility and cytoprotection in vitro, which inhibited the decrease of mitochondrial membrane potential of SH-SY5Y cells and the release of inflammatory factors of BV-2 cells. In MPTP-induced PD mice, Ex-4@DFO NPs could penetrate the BBB into brain, and significantly mitigate the loss of dopaminergic neurons and inflammation in the substantia nigra, finally alleviate the mobility deficits. This self-oriented nanosystem not only improved the biocompatibility of DFO, but also enhanced therapeutic effects synergistically by ameliorating neuronal damage and neuroinflammation, showing a potential therapeutic strategy for PD.

Timely thrombolysis serves as the primary therapeutic approach for ischemic stroke, one of the most serious global public health problems, although reperfusion can cause severe ischemia reperfusion (I/R) injury. Oxidative stress and activation of cell death pathways are the main mechanisms of I/R injury. Our previous studies have demonstrated that iron overload stimulates the generation of reactive oxygen species and facilitates the activation of iron-dependent ferroptosis in the pathogenesis of I/R injury. Removal of excess free iron by deferoxamine (DFO), an iron chelator, may inhibit iron toxicity and reverse I/R-induced neurological deficits. Despite its therapeutic potential, DFO's clinical translation for I/R injury is hampered by rapid systemic clearance, suboptimal bioavailability, and a lack of ischemic lesion-targeting ability. Nanoscale delivery platforms enabling targeted DFO release in stroke lesions may overcome these pharmacokinetic barriers and enhance clinical outcomes. On the basis of the properties of liposomes in carrying hydrophilic substances and crossing the leaky blood-brain barrier in cerebral I/R, we first encapsulated DFO within traditional liposomes to improve its biocompatibility. Subsequently, inspired by the natural homing properties of platelets to damaged blood vessels during I/R injury, the isolated platelet membranes were coated onto the DFO-liposomes, thus endowing the nanodrug with the ability to target stroke lesion. Our results demonstrate that Platesome-DFO exhibits accurate lesion-targeting ability and significantly decreases lesion iron content, thereby preventing neuronal ferroptosis and ultimately reversing neurological deficits in I/R mice. Platesome-DFO provides a novel therapeutic approach for cerebral I/R injury by regulating brain iron status and iron-dependent pathways, highlighting its promising application in the clinical treatment of cerebral I/R injury.

Iron from haemolysed blood is implicated in secondary injury after intracerebral haemorrhage. We aimed to assess the safety of the iron chelator deferoxamine mesylate in patients with intracerebral haemorrhage and to establish whether the drug merits investigation in a phase 3 trial. We did a multicentre, futility-design, randomised, placebo-controlled, double-blind, phase 2 trial at 40 hospitals in Canada and the USA. Adults aged 18–80 years with primary, spontaneous, supratentorial intracerebral haemorrhage were randomly assigned (1:1) to receive deferoxamine mesylate (32 mg/kg per day) or placebo (saline) infusions for 3 consecutive days within 24 h of haemorrhage onset. Randomisation was done via a web-based trial-management system centrally in real time, and treatment allocation was concealed from both participants and investigators. The primary outcome was good clinical outcome, which was defined as a modified Rankin Scale score of 0–2 at day 90. We did a futility analysis: if the 90% upper confidence bound of the absolute risk difference between the two groups in the proportion of participants with a good clinical outcome was less than 12% in favour of deferoxamine mesylate, then to move to a phase 3 efficacy trial would be futile. Primary outcome and safety data were analysed in the modified intention-to-treat population, comprising only participants in whom the study infusions were initiated. This trial is registered with ClinicalTrials.gov, number NCT02175225, and is completed. We recruited 294 participants between Nov 23, 2014, and Nov 10, 2017. The modified intention-to-treat population consisted of 144 patients assigned to the deferoxamine mesylate group and 147 assigned to the placebo group. At day 90, among patients with available data for the primary outcome, 48 (34%) of 140 participants in the deferoxamine mesylate group, and 47 (33%) of 143 patients in the placebo group, had modified Rankin Scale scores of 0–2 (adjusted absolute risk difference 0·6% [90% upper confidence bound 6·8%]). By day 90, 70 serious adverse events were reported in 39 (27%) of 144 patients in the deferoxamine mesylate group, and 78 serious adverse events were reported in 49 (33%) of 147 patients in the placebo group. Ten (7%) participants in the deferoxamine mesylate and 11 (7%) in the placebo group died. None of the deaths were judged to be treatment related. Deferoxamine mesylate was safe. However, the primary result showed that further study of the efficacy of deferoxamine mesylate with anticipation that the drug would significantly improve the chance of good clinical outcome (ie, mRS score of 0–2) at day 90 would be futile. US National Institutes of Health and US National Institute of Neurological Disorders and Stroke.

Significance Diabetes is the leading cause of nontraumatic amputations. There are no effective therapies to prevent diabetic ulcer formation and only modestly effective technologies to help with their healing. To enhance diabetic wound healing we designed a transdermal delivery system containing the FDA-approved small molecule deferoxamine, an iron chelator that increases defective hypoxia inducible factor-1 alpha transactivation in diabetes by preventing iron-catalyzed reactive oxygen stress. This system overcomes the challenge of delivering hydrophilic molecules through the normally impermeable stratum corneum and both prevents diabetic ulcer formation and improves the healing of existing diabetic wounds. This represents a prophylactic pharmacological agent to prevent ulcer formation that is rapidly translatable into the clinic and has the potential to ultimately transform the care and prevention of diabetic complications. There is a high mortality in patients with diabetes and severe pressure ulcers. For example, chronic pressure sores of the heels often lead to limb loss in diabetic patients. A major factor underlying this is reduced neovascularization caused by impaired activity of the transcription factor hypoxia inducible factor-1 alpha (HIF-1α). In diabetes, HIF-1α function is compromised by a high glucose-induced and reactive oxygen species-mediated modification of its coactivator p300, leading to impaired HIF-1α transactivation. We examined whether local enhancement of HIF-1α activity would improve diabetic wound healing and minimize the severity of diabetic ulcers. To improve HIF-1α activity we designed a transdermal drug delivery system (TDDS) containing the FDA-approved small molecule deferoxamine (DFO), an iron chelator that increases HIF-1α transactivation in diabetes by preventing iron-catalyzed reactive oxygen stress. Applying this TDDS to a pressure-induced ulcer model in diabetic mice, we found that transdermal delivery of DFO significantly improved wound healing. Unexpectedly, prophylactic application of this transdermal delivery system also prevented diabetic ulcer formation. DFO-treated wounds demonstrated increased collagen density, improved neovascularization, and reduction of free radical formation, leading to decreased cell death. These findings suggest that transdermal delivery of DFO provides a targeted means to both prevent ulcer formation and accelerate diabetic wound healing with the potential for rapid clinical translation.

Iron functions as an essential micronutrient and participates in normal physiological and biochemical processes in the cardiovascular system. Ferroptosis is a novel type of iron-dependent cell death driven by iron accumulation and lipid peroxidation, characterized by depletion of glutathione and suppression of glutathione peroxidase 4 (GPX4). Dysregulation of iron metabolism and ferroptosis have been implicated in the occurrence and development of cardiovascular diseases (CVDs), including hypertension, atherosclerosis, pulmonary hypertension, myocardial ischemia/reperfusion injury, cardiomyopathy, and heart failure. Iron chelators deferoxamine and dexrazoxane, and lipophilic antioxidants ferrostatin-1 and liproxstatin-1 have been revealed to abolish ferroptosis and suppress lipid peroxidation in atherosclerosis, cardiomyopathy, hypertension, and other CVDs. Notably, inhibition of ferroptosis by ferrostatin-1 has been demonstrated to alleviate cardiac impairments, fibrosis and pathological remodeling during hypertension by potentiating GPX4 signaling. Administration of deferoxamine improved myocardial ischemia/reperfusion injury by inhibiting lipid peroxidation. Several novel small molecules may be effective in the treatment of ferroptosis-mediated CVDs. In this article, we summarize the regulatory roles and underlying mechanisms of iron metabolism dysregulation and ferroptosis in the occurrence and development of CVDs. Targeting iron metabolism and ferroptosis are potential therapeutic strategies in the prevention and treatment of hypertension and other CVDs.

Deferoxamine (DFO) is a siderophore widely studied for its ability to bind iron(III) strongly. Thanks to its versatility, it is suitable for several clinical and analytical applications, from the recognized iron(III) chelation therapy to the most recent applications in sensing. The presence of three hydroxamic functional groups enables Deferoxamine to form stable complexes with iron(III) and other divalent and trivalent metal ions. Moreover, the terminal amino group in the DFO molecule, not involved in metal ion complexation, allows modification or functionalization of solid phases, nanoobjects, biopolymers, electrodes and optical devices. This review summarizes and discusses deferoxamine-based applications for the chelation and recognition of Fe(III).

Magnetic resonance (MR) imaging is a powerful imaging modality for obtaining anatomical information with high spatial and temporal resolution. In the drug delivery system (DDS) framework, nanoparticles such as liposomes are potential candidates for MR imaging. We validated that RGD peptides are possible targeting molecules for pancreatic cancer with α v β 3 integrin expression. This study aimed to evaluate RGD-modified liposomes loaded with ferrioxamine B for pancreatic cancer imaging. We synthesized four types of RGD-modified liposomes encapsulated with ferrioxamine B (SH-, H-, M-, and L-RGD-liposomes). The binding affinity of RGD-modified liposomes was evaluated in a competitive inhibition study using 125 I-echistatin. To investigate the pharmacokinetics of RGD-modified liposomes, a biodistribution study using RGD-liposomes labeled with 111 In was carried out in a human pancreatic cancer PANC-1 xenograft mouse model. Finally, MR was performed using ferrioxamine-B-loaded liposomes. RGD-liposomes inhibited the binding of 125 I-echistatin to RGD. The biodistribution study revealed that 111 In-RGD-liposomes accumulated significantly in the liver and spleen. Among the 111 In-RGD-liposomes, 111 In-H-RGD-liposomes showed the highest tumor-to-normal tissue ratio. In the MR study, H-RGD-liposomes loaded with ferrioxamine B showed higher tumor-to-muscle signal ratios than RKG-liposomes loaded with ferrioxamine B (control). We successfully synthesized RGD-liposomes that can target α v β 3 integrin.

Intracerebral hemorrhage (ICH) is a significant cause of morbidity and mortality worldwide. Several recent controlled trials have reported that deferoxamine (DFX) therapy appears to be effective for ICH. The aim of this study was to perform a systematic review of DFX therapy for ICH patients and evaluate the efficacy and safety of DFX therapy for ICH patients. We searched Medline, Embase, the Cochrane Database of Systematic Reviews, clinicaltrials.gov, all Chinese databases and the reference lists of all included studies and review articles. We then performed a systematic review of studies involving the administration of DFX following ICH. Only two studies were included, a prospective, randomized clinical trial and a prospective,observational cohort study with concurrent groups. Qualitative analysis of each study revealed one randomized controlled trial of moderate quality with a moderate risk of bias and one observational cohort study of moderate quality with a moderate risk of bias. DFX may be an effective treatment for edema in patients with ICH. However, due to the small number of trials and small sample sizes of these trials, insufficient evidence exists to determine the effect of DFX on neurologic outcomes after ICH and the safety of this intervention. Further investigation is required before DFX can become a routine treatment for ICH.

Background Hemoglobin degradation products, in particular iron, have been implicated in secondary neuronal injury following intracerebral hemorrhage (ICH). The iron chelator Deferoxamine Mesylate (DFO) exerts diverse neuroprotective effects, reduces perihematoma edema (PHE) and neuronal damage, and improves functional recovery after experimental ICH. We hypothesize that treatment with DFO could minimize neuronal injury and improve outcome in ICH patients. As a prelude to test this hypothesis, we conducted a Phase I, open-label study to determine the tolerability, safety, and maximum tolerated dose (MTD) of DFO in patients with ICH. Intravenous infusions of DFO in doses up to 62 mg/kg/day (up to a maximum of 6000 mg/day) were well-tolerated and did not seem to increase serious adverse events (SAEs) or mortality. We have initiated a multi-center, double-blind, randomized, placebo-controlled, Phase II clinical trial (High Dose Deferoxamine [HI-DEF] in Intracerebral Hemorrhage) to determine if it is futile to move DFO forward to Phase III efficacy evaluation. Methods We will randomize 324 subjects with spontaneous ICH to either DFO at 62 mg/kg/day (up to a maximum daily dose of 6000 mg/day) or saline placebo, given by intravenous infusion for 5 consecutive days. Treatment will be initiated within 24 hours after ICH symptom onset. All subjects will be followed for 3 months and will receive standard of care therapy while participating in the study. At 3 months, the proportion of DFO-treated subjects with a good clinical outcome, assessed by modified Rankin Scale, will be compared to the placebo proportion in a futility analysis. Conclusions The Hi-Def trial is expected to advance our understanding of the pathopgysiology of secondary neuronal injury in ICH and will provide a crucial “Go/No Go” signal as to whether a Phase III trial to investigate the efficacy of DFO is warranted.