Eprosartan: A closer insight into its neuroprotective activity in rats with focal cerebral ischemia-reperfusion injury

Eprosartan (EPRO), an angiotensin receptor type-1 (AT-1) blocker, exhibited neuroprotective activities in ischemic stroke resulting from focal cerebral ischemia in rats. The current study aimed to clarify the neuroprotective role of EPRO in middle carotid artery occlusion (MCAO)-induced ischemic stroke in rats. Fifty-six male Wistar rats were divided into four groups (n = 14 per group): sham-operated group, sham receiving EPRO (60 mg/kg/day, po) group, ischemia-reperfusion (IR) group, and IR receiving EPRO (60 mg/kg/day, po) group. MCAO led to a remarkable impairment in motor function together with stimulation of inflammatory and apoptotic pathways in the hippocampus of rats. After MCAO, the AT1 receptor in the brain was stimulated, resulting in activation of Janus kinase 2/signal transducers and activators of transcription 3 signaling generating more neuroinflammatory milieu and destructive actions on the hippocampus. Augmentation of caspase-3 level by MCAO enhanced neuronal apoptosis synchronized with neurodegenerative effects of oxidative stress biomarkers. Pretreatment with EPRO opposed motor impairment and decreased oxidative and apoptotic mediators in the hippocampus of rats. The anti-inflammatory activity of EPRO was revealed by downregulation of nuclear factor-kappa B and tumor necrosis factor-β levels and (C-X-C motif) ligand 1 messenger RNA (mRNA) expression. Moreover, the study confirmed the role of EPRO against a unique pathway of hypoxia-inducible factor-1α and its subsequent inflammatory mediators. Furthermore, upregulation of caveolin-1 mRNA level was also observed along with decreased oxidative stress marker levels and brain edema. Therefore, EPRO showed neuroprotective effects in MCAO-induced cerebral ischemia in rats via attenuation of oxidative, apoptotic, and inflammatory pathways.

Clinical Effects of Early Edaravone Use in Acute Ischemic Stroke Patients Treated by Endovascular Reperfusion Therapy

Background and Purpose- Although several clinical studies suggested the beneficial effects of edaravone in acute ischemic stroke, most were performed under settings that differ from those in the current treatment strategy, which has dramatically changed with progress in reperfusion therapies. This study aimed to evaluate the efficacy of edaravone in patients with acute ischemic stroke treated by emergent endovascular reperfusion therapy. Methods- We conducted a retrospective observational study using a national administrative database. Patients with acute ischemic stroke treated by emergent endovascular reperfusion therapy were identified and dichotomized by whether edaravone was used within 2 days of admission. We compared the functional independence at hospital discharge, in-hospital mortality, and intracranial hemorrhage after admission between groups, adjusted by a well-validated case-mix adjustment model, in multivariate mixed-effect regression and propensity score matching analyses. Results- Of 11 508 patients eligible for analysis, 10 281 (89.3%) received edaravone therapy. The established risk adjustment model had good predictability for functional independence at hospital discharge, with an area under the receiver operating characteristic curve of 0.74. In the mixed-effect regression analysis, edaravone use was significantly associated with greater functional independence at hospital discharge (32.3% in the edaravone group versus 25.9% in the control group; adjusted odds ratio, 1.21; 95% confidence interval, 1.03-1.41), lower in-hospital mortality (9.9% in the edaravone group versus 17.4% in the control group; adjusted odds ratio, 0.52; 95% confidence interval, 0.43-0.62), and reduced intracranial hemorrhage after admission (1.4% in the edaravone group versus 2.7% in the control group; adjusted odds ratio, 0.55; 95% confidence interval, 0.37-0.82). Results of the propensity score matching analysis corroborated these results. Conclusions- This retrospective analysis of a Japanese nationwide administrative database suggested that combination therapy with edaravone and endovascular reperfusion therapy could be a promising therapeutic strategy in acute ischemic stroke. Further randomized control trials are warranted.

Self-nanomicellizing solid dispersion of edaravone: part II: in vivo assessment of efficacy against behavior deficits and safety in Alzheimer's disease model

Background

Alzheimer’s disease (AD) is a devastating neurodegenerative disorder that lacks any disease-modifying drug for the prevention and treatment. Edaravone (EDR), an approved free radical scavenger, has proven to have potential against AD by targeting multiple key pathologies including amyloid-beta (Aβ), tau phosphorylation, oxidative stress, and neuroinflammation. To enable its oral use, novel edaravone formulation (NEF) was previously developed. The aim of the present investigation was to evaluate safety and efficacy of NEF by using in vitro/in vivo disease model.

Materials and methods

In vitro therapeutic potential of NEF over EDR was studied against the cytotoxicity induced by copper metal ion, H₂O₂ and Aβ42 oligomer, and cellular uptake on SH-SY5Y695 amyloid-β precursor protein (APP) human neuroblastoma cell line. For in vivo safety and efficacy assessment, totally seven groups of APP/PS1 (five treatment groups, one each as a basal and sham control) and one group of C57BL/6 mice as a positive control for behavior tests were used. Three groups were orally treated for 3 months with NEF at an equivalent dose of EDR 46, 138, and 414 µmol/kg, whereas one group was supplied with each Donepezil (5.27 µM/kg) and Soluplus (amount present in NEF of 414 µmol/kg dose of EDR). Behavior tests were conducted to assess motor function (open-field), anxiety-related behavior (open-field), and cognitive function (novel objective recognition test, Y-maze, and Morris water maze). For the safety assessment, general behavior, adverse effects, and mortality were recorded during the treatment period. Moreover, biochemical, hematological, and morphological parameters were determined.

Results

Compared to EDR, NEF showed superior cellular uptake and neuroprotective effect in SH-SY5Y695 APP cell line. Furthermore, it showed nontoxicity of NEF up to 414 µM/kg dose of EDR and its potential to reverse AD-like behavior deficits of APP/PS1 mice in a dose-dependent manner.

Conclusion

Our results indicate that oral delivery of NEF holds a promise as a safe and effective therapeutic agent for AD.

What can we learn from the edaravone development program for ALS?

Edaravone's development into an ALS therapeutic has been a process which began with preclinical studies regarding its potential in targeting ALS. Despite edaravone's inability to show benefit in a general ALS population, an important post-hoc analysis showed that a clinical subset of patients had benefit. Most importantly, a subsequent study examining the capacity of edaravone to have benefit in this specific subset of ALS patients was successful in meeting its primary outcome measures. Questions regarding whether the dosing regimen could be simplified or improved, the duration of the effects, and the timing of the potential treatment to different stages of disease remain to be answered. However, the benefit of this compound in delivering a meaningful therapy to ALS patients and the lessons learned with regard to its development should widen interest in clinical research so that additional strategies for treating ALS may become available to patients.

Edaravone offers neuroprotection for acute diabetic stroke patients

INTRODUCTION

Edaravone, a novel free-radical scavenger, has been shown to alleviate cerebral ischemic injury and protect against vascular endothelial dysfunction. However, the effects of edaravone in acute diabetic stroke patients remain undetermined.

METHODS

A randomized, double-blind, placebo-controlled study was performed to prospectively evaluate the effects of edaravone on acute diabetic stroke patients admitted to our hospital within 24 h of stroke onset. The edaravone group received edaravone (30 mg twice per day) diluted with 100 ml of saline combined with antiplatelet drug aspirin and atorvastatin for 14 days. The non-edaravone group was treated only with 100 ml of saline twice per day combined with aspirin and atorvastatin. Upon admission, and on days 7, 14 post-stroke onset, neurological deficits and activities of daily living were assessed using the National Institutes of Health Stroke Scale (NIHSS) and the Barthel Index (BI), respectively. The occurrence of hemorrhage transformation, pulmonary infection, progressive stroke and epilepsy was also evaluated on day 14 post-treatment.

RESULTS

A total of 65 consecutive acute diabetic stroke patients were enrolled, of whom 35 were allocated to the edaravone group and 30 to the non-edaravone group. There was no significant group difference in baseline clinical characteristics, but mean NIHSS scores were lower (60 %), and BI scores were 1.7-fold higher, in edaravone-treated patients vs. controls on day 14. Furthermore, the incidence of hemorrhage transformation, pulmonary infection, progressive stroke and epilepsy was markedly reduced in the edaravone vs. non-edaravone group.

CONCLUSION

Edaravone represents a promising neuroprotectant against cerebral ischemic injury in diabetic patients.

Effect of free radical scavenger, edaravone, for patients with carbon monoxide poisoning

OBJECTIVE

Chronic neurological symptoms after carbon monoxide (CO) poisoning are caused by various biological processes in the damaged brain, with free radicals playing roles as mediators in establishing pathological processes leading to chronic neurological symptoms under CO poisoning. This study aimed to clarify the effects of a free radical scavenger, edaravone, in patients with CO poisoning.

METHODS

We retrospectively compared two groups comprising patients treated with hyperbaric oxygenation alone (Group A, n=25) or edaravone in addition to hyperbaric oxygenation (Group B, n=25). Edaravone was administrated intravenously at 30 mg every 12h for 7 days. Patient characteristics, general conditions on admission, and frequency of chronic neurological symptoms were compared between groups. Among patients showing chronic neurological symptoms, cognitive function and daily activity were also compared between groups.

RESULTS

No significant differences in characteristics or general conditions on admission were identified between groups. In Group B, no patients presented with marked complications caused by edaravone. Although chronic persisting symptoms were less frequent in Group B (n=1, 0.04%) than in Group A (n=5, 20%), this difference was not significant. In the 11 patients showing chronic symptoms, scores for cognitive function and daily activity in the chronic phase were better in Group B than in Group A, but no significant differences were apparent.

CONCLUSIONS

The present results suggest that edaravone represents a tolerable and feasible treatment for CO-poisoned patients. Further studies are needed to clarify whether edaravone can favorably influence chronic neurological symptoms caused by CO poisoning.

The free-radical scavenger edaravone accelerates thrombolysis with alteplase in an experimental thrombosis model

BACKGROUND AND PURPOSE

Reperfusion injury after thrombolytic therapy can have adverse neurologic effects. The free-radical scavenger edaravone is used in combination with the recombinant tissue plasminogen activator alteplase to treat acute ischemic stroke. However, basic investigations of this combination use remain inadequate. Here, we used an in vivo model to investigate the effects of edaravone on alteplase-induced thrombolysis.

METHODS

Thrombolysis was evaluated by using a He-Ne-laser-induced thrombosis model in rat mesenteric microvessels. Changes in thrombus volume were analyzed with the image analysis software Image-Pro Plus (Media Cybernetics, USA). There were three experimental groups (placebo, alteplase 0.6 mg/kg, alteplase 0.6 mg/kg + edaravone 10.5 mg/kg). Sequential changes (0 to 60 min) in thrombus volume were compared by using a relative optical density method that we had used previously.

RESULTS

In the placebo group, the thrombus volume at 60 min, reflecting the extent of thrombolysis, was 97.2% ± 5.7% of the initial value. In the alteplase group, thrombus volume decreased to 70.7% ± 4.1% (P<0.01) after 20 min and 14.2% ± 6.6% after 60 min. In the alteplase+edaravone group, thrombus volume decreased to 66.9% ± 7.2% (P<0.001) after 10 min and 10.9% ± 2.3% after 60 min.

CONCLUSIONS

These results support the hypothesis that edaravone accelerates thrombolysis by alteplase.

Antioxidants: The new frontier for translational research in cerebroprotection

It is important for the anesthesiologist to understand the etiology of free radical damage and how free-radical scavengers attenuate this, so that this knowledge can be applied to diverse neuro-pathological conditions. This review will concentrate on the role of reactive species of oxygen in the pathophysiology of organ dysfunction, specifically sub arachnoid hemorrhage (SAH), traumatic brain injury (TBI) as well as global central nervous system (CNS) hypoxic, ischemic and reperfusion states. We enumerate potential therapeutic modalities that are been currently investigated and of interest for future trials. Antioxidants are perhaps the next frontier of translational research, especially in neuro-anesthesiology.

The efficacy of edaravone (radicut), a free radical scavenger, for cardiovascular disease

Edaravone was originally developed as a potent free radical scavenger, and has been widely used to treat acute ischemic stroke in Japan since 2001. Free radicals play an important role in the pathogenesis of a variety of diseases, such as cardiovascular diseases and stroke. Therefore, free radicals may be targets for therapeutic intervention in these diseases. Edaravone shows protective effects on ischemic insults and inflammation in the heart, vessel, and brain in experimental studies. As well as scavenging free radicals, edaravone has anti-apoptotic, anti-necrotic, and anti-cytokine effects in cardiovascular diseases and stroke. Edaravone has preventive effects on myocardial injury following ischemia and reperfusion in patients with acute myocardial infarction. Edaravone may represent a new therapeutic intervention for endothelial dysfunction in the setting of atherosclerosis, heart failure, diabetes, or hypertension, because these diseases result from oxidative stress and/or cytokine-induced apoptosis. This review evaluates the potential of edaravone for treatment of cardiovascular disease, and covers clinical and experimental studies conducted between 1984 and 2013. We propose that edaravone, which scavenges free radicals, may offer a novel option for treatment of cardiovascular diseases. However, additional clinical studies are necessary to verify the efficacy of edaravone.

The effect of the ALAnerv nutritional supplement on some oxidative stress markers in postacute stroke patients undergoing rehabilitation

Stroke is a pathologic condition associated with redox imbalance. This pilot study was designed to evaluate the effect of the consumption of the nutritional supplement ALAnerv on some oxidative stress markers in postacute stroke patients undergoing rehabilitation. To achieve this goal, we assigned 28 patients to 2 study groups: (-)ALA and (+)ALA. Patients in both groups participated in the same rehabilitation program and received comparable standard medications; however, patients in the (+)ALA group received ALAnerv for 2 weeks (2 pills per day). We assessed total and nonproteic thiols, protein carbonyls, ceruloplasmin, oxidized low-density lipoprotein (LDL) particles, lipid hydroperoxide concentrations, gamma-glutamyl transpeptidase activity, and total antioxidant capacity. Regression analysis indicated that supplementation with ALAnerv was responsible for the significant decrease in glucose (p = 0.002) and oxidized LDL particles (p < 0.001) during the study period. For both parameters, the variation in the percent of concentration between the 2 groups during the study period reached statistical significance (p = 0.012 and p < 0.001, respectively). Moreover, Barthel Index values at discharge were significantly influenced by ALAnerv treatment. These preliminary results indicate that ALAnerv might be helpful because it rapidly corrects plasma fasting glucose and corrects serum oxidized LDL particle concentrations, suggesting the need for longer treatment with 2 pills or more per day.

Edaravone (Radicut), a free radical scavenger, is a potentially useful addition to thrombolytic therapy in patients with acute ischemic stroke

Acute ischemic stroke (AIS) is a major cause of morbidity and mortality in the aging population worldwide. Alteplase, a recombinant tissue plasminogen activator, is the only Food and Drug Administration-approved thrombolytic agent for the treatment of AIS. Only 2-5% of patients with stroke receive thrombolytic treatment, mainly due to delay in reaching the hospital. Edaravone is a free radical scavenger marketed in Japan to treat patients with AIS, who present within 24 h of the onset of symptoms. When used in combination with alteplase, edaravone may have three useful effects: enhancement of early recanalization, inhibition of alteplase-induced hemorrhagic transformation and extension of the therapeutic time window for alteplase. This is the first review of the literature evaluating the clinical efficacy of edaravone, aiming to clarify whether edaravone should be further evaluated for clinical use worldwide. This review covers both clinical and experimental studies conducted between 1994 and 2012. Edaravone is a potentially useful neurovascular protective agent, used in combination with thrombolytic agents to treat >15 million patients devastated by stroke worldwide annually. Additional clinical studies are necessary to verify the efficacy of edaravone when used in combination with a thrombolytic agent.

Clinical neuroprotective drugs for treatment and prevention of stroke

Stroke is an enormous public health problem with an imperative need for more effective therapies. In therapies for ischemic stroke, tissue plasminogen activators, antiplatelet agents and anticoagulants are used mainly for their antithrombotic effects. However, free radical scavengers, minocycline and growth factors have shown neuroprotective effects in the treatment of stroke, while antihypertensive drugs, lipid-lowering drugs and hypoglycemic drugs have shown beneficial effects for the prevention of stroke. In the present review, we evaluate the treatment and prevention of stroke in light of clinical studies and discuss new anti-stroke effects other than the main effects of drugs, focusing on optimal pharmacotherapy.

Ginsenoside-Rd improves outcome of acute ischaemic stroke - a randomized, double-blind, placebo-controlled, multicenter trial

BACKGROUND AND PURPOSE

 Ginsenoside-Rd is a receptor-operated calcium channel antagonist and has shown promise as a neuroprotectant in our phase II study. As an extended work, we sought to confirm its efficacy and safety of Ginsenoside-Rd in patients with acute ischaemic stroke.

METHODS

We conducted a randomized, double-blind, placebo-controlled trial involving 390 patients with acute ischaemic stroke in a 3:1 ratio to receive a 14-day intravenous infusion of Ginsenoside-Rd or placebo within 72 h after the onset of stroke. Our primary end-point was the distribution of disability scores on the modified Rankin scale (mRs) at 90 days.

RESULTS

  The efficacy analysis was based on 386 patients (Ginsenoside-Rd group: 290; placebo group: 96). Ginsenoside-Rd significantly improved the overall distribution of scores on the mRs, as compared with the placebo (P = 0.02; odds ratios [OR], 1.74; 95% confidence interval [CI], 1.08-2.78). There were significant differences between the two groups when we categorized the scores into 0-1 vs. 2-5 (P = 0.01; OR, 2.32; 95% CI, 1.23-4.38; 66.8% vs. 53.1%). It also improved the National Institutes of Health Stroke Scale (NIHSS) at 15 days [P < 0.01; least squares mean (LSM), -0.77; 95% CI, -1.31 to -0.24]. Mortality and rates of adverse events were similar in the two groups.

CONCLUSIONS

  Ginsenoside-Rd improved the primary outcome of acute ischaemic stroke and had an acceptable adverse-event profile.

Effects of edaravone on muscle atrophy and locomotor function in patients with ischemic stroke: a randomized controlled pilot study

BACKGROUND AND OBJECTIVE

Stroke patients with severe leg paralysis are often bedridden in the acute and subacute phase, which increases the risk of disuse muscle atrophy in the chronic phase. The evidence to date indicates that oxidative stress plays an important role in the mechanism of disuse muscle atrophy. Therefore, the aim of this study was to determine if long-term radical scavenger treatment with edaravone following an acute stroke prevents the progression of disuse muscle atrophy and improves leg locomotor function in the chronic phase.

METHODS

This randomized controlled pilot study was conducted at 19 acute stroke and rehabilitation centers across Japan. Forty-seven ischemic stroke patients with at least leg motor weakness admitted within 24 hours of onset were randomly assigned to receive continuous intravenous infusions of edaravone 30 mg twice daily for 3 days (short-term group) or 10-14 days (long-term group). The primary endpoints of the study included the degree of leg disuse muscle atrophy, as measured by the percentage change from baseline in femoral muscle circumference 15 cm above the knee, and the improvement in leg locomotor function, as assessed by the maximum walking speed over 10 m, 3 months after the onset of stroke.

RESULTS

Three-month follow-up was completed by a total of 41 patients (21 in the short-term group and 20 in the long-term group). On admission, there was no significant difference in the severity of stroke or the grade of leg paresis between the two treatment groups. The grade of disuse muscle atrophy and incidence of gait impairment 3 weeks after stroke onset were also similar between the short- and long-term groups. However, disuse muscle atrophy of the paretic and non-paretic legs was significantly less severe in the long-term versus the short-term treatment group (3.6 ± 5.9% and 1.5 ± 6.0% vs 8.3 ± 5.2% and 5.7 ± 6.4%; p < 0.01 and p < 0.05) 3 months after stroke onset. Additionally, the maximum walking speed over a distance of 10 m was significantly greater in the long-term group (98 ± 67 vs 54 ± 55 cm/sec; p < 0.05).

CONCLUSION

Edaravone treatment for up to 14 days suppresses the progression of disuse muscle atrophy and improves leg locomotor function to a greater extent than shorter-term treatment in acute stroke patients. This suggests that the management of stroke may be improved with long-term edaravone therapy by providing myoprotective effects that ameliorate functional outcome in the chronic phase.

Potential of edaravone for neuroprotection in neurologic diseases that do not involve cerebral infarction

Edaravone was originally developed as a potent free radical scavenger and has been widely used to treat cerebral infarction in Japan since 2001. Several free radical scavengers have been developed and some of them have progressed to clinical trials for the treatment of cerebral infarction. One such scavenger, edaravone, has been approved by the regulatory authority in Japan for the treatment of patients with cerebral infarction. Of particular interest is the ability of edaravone to diffuse into the central nervous system in various neurologic diseases. Aside from its hydroxyl radical scavenging effect, edaravone has been found to have beneficial effects on inflammation, matrix metalloproteinases, nitric oxide production and apoptotic cell death. Concordantly, edaravone has been found to have neuroprotective effects in a number of animal models of disease, including stroke, spinal cord injury, traumatic brain injury, neurodegenerative diseases and brain tumors. The proven safety of edaravone following 9 years of use as a free radical scavenger suggests that it may have potential for development into an effective treatment of multiple neurologic conditions in humans.

Dynamic of oxidative and nitrosative stress markers during the convalescent period of stroke patients undergoing rehabilitation

Background

Stroke patients have a redox imbalance, a consequence of both the cerebrovascular event and the associated pathological conditions. Our study was aimed to investigate the dynamic of some oxidative and nitrosative markers during the convalescent phase of postacute stroke patients undergoing rehabilitation.

Methods

We assessed thiol, advanced oxidation protein product, protein carbonyl, 3-nitro-l-tyrosine, ceruloplasmin and oxidized LDL concentrations, as well as gamma-glutamyltranspeptidase (GGT) activity in 20 patients at the beginning of the hospitalization and at the discharge moment, respectively, and 24 apparently healthy controls.

Results

We found significantly increased values for GGT ( P = 0.04), ceruloplasmin ( P = 0.01) and protein carbonyl ( P = 0.04) in stroke patients at the hospitalization moment when compared with healthy controls, while total thiols were significantly decreased ( P = 0.002). Rehabilitation was associated with a significant decrease of protein carbonyl ( P = 0.03) and oxidized LDL particle concentrations ( P = 0.03), as well as GGT activity ( P = 0.02). At the hospitalization moment, both GGT and ceruloplasmin were significantly negatively correlated with non-proteic thiols ( r = −0.44, P = 0.049, and r = −0.53, P = 0.015, respectively) and significantly positively with protein carbonyls ( r = +0.80, P < 0.001, and r = +0.69, P < 0.001, respectively) suggesting putative roles of GGT and ceruloplasmin in the redox imbalance.

Conclusions

These results highlight the existence of a redox imbalance in postacute stroke patients, and the possible benefits of an antioxidant-based therapy for the recovery of these patients.

Edaravone: a new therapeutic approach for the treatment of acute stroke

Acute stroke, including acute ischemic stroke (AIS) and acute hemorrhagic stroke, (AHS) is a common medical problem with particular relevance to the demographic changes in industrialized societies. In recent years, treatments for AIS have emerged, including thrombolysis with tissue plasminogen activator (t-PA). Although t-PA is the most effective currently available therapy, it is limited by a narrow therapeutic time window and side effects, and only 3% of all AIS patients receive thrombolysis. Edaravone was originally developed as a potent free radical scavenger and, since 2001, has been widely used to treat AIS in Japan. It was shown that edaravone extended the narrow therapeutic time window of t-PA in rats. The therapeutic time window is very important for the treatment of AIS, and early edaravone treatment is more effective. Thus, more AIS patients might be rescued by administering edaravone with t-PA. Meanwhile, edaravone attenuates AHS-induced brain edema, neurologic deficits and oxidative injury in rats. Although edaravone treatment is currently only indicated for AIS, it does offer neuroprotective effects against AHS in rats. Therefore, we hypothesize that early administration of edaravone can rescue AHS patients as well as AIS patients. Taken together, our findings suggest that edaravone should be immediately administered on suspicion of acute stroke, including AIS and AHS.

A critical assessment of edaravone acute ischemic stroke efficacy trials: is edaravone an effective neuroprotective therapy?

IMPORTANCE OF THE FIELD

Edaravone (Radicut) is a free radical scavenger marketed in Japan by Mitsubishi Tanabe Pharma Corp. to treat acute ischemic stroke (AIS) patients presenting within 24 h of the attack. Injectable edaravone ampoules (30 mg b.i.d., i.v., 14 days) were first approved on 23 May 2001. On 19 January 2010, as a new innovation, the Radicut BAG (Intravenous BAG) was approved by the Japanese Ministry of Health and Welfare. Efficacy of edaravone ranges from large significant clinical improvements to only modest improvements in clinical function measured using standard stroke scales when administered 6-72 h following an ischemic stroke. With almost 17 years of edaravone clinical experience, a few adverse events--including acute renal failure--have been noted.

WHAT THE READER WILL GAIN

This is the only article to date to critically review available clinical efficacy and toxicology data published in the literature to ascertain whether edaravone should be further pursued as a candidate for development worldwide.

AREAS COVERED IN THIS REVIEW

This review covers clinical studies carried out over the period 1993-2008.

TAKE HOME MESSAGE

Edaravone may be a useful neuroprotective agent to treat the > 15 million victims worldwide who are devastated by stroke annually. Additional clinical studies are necessary to verify the efficacy of edaravone.