Effect of edaravone therapy in Korean amyotrophic lateral sclerosis (ALS) patients

The Role of Ferroptosis in Amyotrophic Lateral Sclerosis Treatment

Amyotrophic lateral sclerosis (ALS) is a rare neurodegenerative disease with a challenging treatment landscape, due to its complex pathogenesis and limited availability of clinical drugs. Ferroptosis, an iron-dependent form of programmed cell death (PCD), stands distinct from apoptosis, necrosis, autophagy, and other cell death mechanisms. Recent studies have increasingly highlighted the role of iron deposition, reactive oxygen species (ROS) accumulation, oxidative stress, as well as systemic Xc- and glutamate accumulation in the antioxidant system in the pathogenesis of amyotrophic lateral sclerosis. Therefore, targeting ferroptosis emerges as a promising strategy for amyotrophic lateral sclerosis treatment. This review introduces the regulatory mechanism of ferroptosis, the relationship between amyotrophic lateral sclerosis and ferroptosis, and the drugs used in the clinic, then discusses the current status of amyotrophic lateral sclerosis treatment, hoping to provide new directions and targets for its treatment.

Edaravone for patients with amyotrophic lateral sclerosis: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

The effectiveness and long-term efficacy of edaravone, a recommended treatment for amyotrophic lateral sclerosis (ALS), has not been examined in real-world settings. This study aims to evaluate the effectiveness and long-term efficacy of edaravone.

METHODS

The OVID Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science databases were searched for articles published between January 1, 2000, and May 1, 2023. Two investigators independently screened the retrieved articles for randomized controlled trials (RCTs), cohort studies, or single-arm trials that evaluated the effect of edaravone on amyotrophic lateral sclerosis (ALS). The risk of bias was evaluated using the revised Cochrane Risk-of-Bias (RoB 2.0) tool for randomized controlled trials (RCTs) and the Risk-of-Bias In Non-randomized Studies of Interventions (ROBINS-I) tool for observational studies. The primary outcome was the ALSFRS-R score assessed at month 6, with secondary outcomes including the ALSFRS-R scores evaluated at months 9, 12, and 18, forced vital capacity (FVC), and adverse events. The certainty of evidence was assessed using the GRADE approach.

RESULTS

The analysis included 16 studies with a total of 4828 participants. Among these, four were randomized controlled trials (RCTs) and 12 were observational studies. Of the RCTs, four were rated as having a low risk of bias, while six of the observational studies were rated as having a low risk of bias. Edaravone was associated with slightly slower progression in the reduction of ALSFRS-R score at month 6 compared to placebo (mean difference 1.01, 95%CI -0.87 to 3.09, p = 0.293), as shown by evidence from RCTs. However, observational studies did not show any benefit of adding edaravone to routine practice (mean difference 1.85, 95%CI -2.05 to 5.75, p = 0.352). The change from baseline in ALSFRS-R score was -2.1, -4.04, -7.5, -6.82, and -7.9 at months 3, 6, 9, 12, and 18, respectively. The GRADE assessment indicated moderate certainty for evidence from RCTs, while evidence from observational studies had very low certainty.

CONCLUSION

Due to the limited number of studies and confounding issues in observational studies, further examination of the added benefits of edaravone to routine practice is necessary through RCTs, particularly regarding its long-term efficacy.

Identification and characterization of novel ERBB4 variant associated with sporadic amyotrophic lateral sclerosis (ALS)

Amyotrophic Lateral Sclerosis (ALS) is the most common type of motor neuron disease characterized by progressive motor neuron degeneration in brain and spinal cord. Most cases are sporadic in ALS and 5-10% of cases are familiar. >50 genes are known to be associated with ALS and one of them is ERBB4. In this paper, we report the case of a 53-year-old ALS patient with progressive muscle weakness and fasciculation, but he had no cognitive decline. We performed the next generation sequencing (NGS) and in silico analysis, it predicted a highly pathogenic variant, c.2116 A > G, p.Asn706Asp (N706D) in the ERBB4 gene. The amino acid residue is highly conserved among species. ERBB4 is a member of the ERBB family of receptor tyrosine kinases. ERBB4 has multiple tyrosine phosphorylation sites, including an autophosphorylation site at tyrosine 1284 residue. Autophosphorylation of ERBB4 promotes biological activity and it associated with NRG-1/ERBB4 pathway. It is already known that tyrosine 128 phosphorylation of ERBB4 is decreased in patients who have ALS-associated ERBB4 mutations. We generated ERBB4 N706D construct using site-directed mutagenesis and checked the phosphorylation level of ERBB4 N706D in NSC-34 cells. We found that the phosphorylation of ERBB4 N706D was decreased compared to ERBB4 wild-type, indicating a loss of function mutation in ERBB4. We report a novel variant in ERBB4 gene leading to ALS through dysfunction of ERBB4.

Brain-derived neurotrophic factor/tropomyosin receptor kinase B signaling in spinal muscular atrophy and amyotrophic lateral sclerosis

Tropomyosin receptor kinase B (TrkB) and its primary ligand brain-derived neurotrophic factor (BDNF) are expressed in the neuromuscular system, where they affect neuronal survival, differentiation, and functions. Changes in BDNF levels and full-length TrkB (TrkB-FL) signaling have been revealed in spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS), two common forms of motor neuron diseases that are characterized by defective neuromuscular junctions in early disease stages and subsequently progressive muscle weakness. This review summarizes the current understanding of BDNF/TrkB-FL-related research in SMA and ALS, with an emphasis on their alterations in the neuromuscular system and possible BDNF/TrkB-FL-targeting therapeutic strategies. The limitations of current studies and future directions are also discussed, giving the hope of discovering novel and effective treatments.

Masitinib: The promising actor in the next season of the Amyotrophic Lateral Sclerosis treatment series

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease with high mortality and morbidity rate affecting both upper and lower motor neurons (MN). Muscle force reduction, behavioral change, pseudobulbar affect, and cognitive impairments are the most common clinical manifestations of ALS. The main physiopathology of ALS is still unclear, though several studies have identified that oxidative stress, proteinopathies, glutamate-related excitotoxicity, microglial activation, and neuroinflammation may be involved in the pathogenesis of ALS. From 1995 until October 2022, only Riluzole, Dextromethorphan Hydrobromide (DH) with Quinidine sulfate (Q), Edaravone, and Sodium phenylbutyrate with Taurursodiol (PB/TUDCO) have achieved FDA approval for ALS treatment. Despite the use of these four approved agents, the survival rate and quality of life of ALS patients are still low. Thus, finding novel treatments for ALS patients is an urgent requirement. Masitinib, a tyrosine kinase inhibitor, emphasizes the neuro-inflammatory activity of ALS by targeting macrophages, mast cells, and microglia cells. Masitinib downregulates the proinflammatory cytokines, indirectly reduces inflammation, and induces neuroprotection. Also, it was effective in phase 2/3 and 3 clinical trials (CTs) by increasing overall survival and delaying motor, bulbar, and respiratory function deterioration. This review describes the pathophysiology of ALS, focusing on Masitinib's mechanism of action and explaining why Masitinib could be a promising actor in the treatment of ALS patients. In addition, Masitinib CTs and other competitor drugs in phase 3 CTs have been discussed.

Quercetin activates the Sestrin2/AMPK/SIRT1 axis to improve amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a chronic neurodegenerative disease with poor prognosis. The intricacies surrounding its pathophysiology could partly account for the lack of effective treatment for ALS. Sestrin2 has been reported to improve metabolic, cardiovascular and neurodegenerative diseases, and is involved in the direct and indirect activation of the adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/silent information regulator 1 (SIRT1) axis. Quercetin, as a phytochemical, has considerable biological activities, such as anti-oxidation, anti-inflammation, anti-tumorigenicity, and neuroprotection. Interestingly, quercetin can activate the AMPK/SIRT1 signaling pathway to reduce endoplasmic reticulum stress, and alleviate apoptosis and inflammation. This report examines the molecular relationship between Sestrin2 and AMPK/SIRT1 axis, as well as the main biological functions and research progress of quercetin, together with the correlation between quercetin and Sestrin2/AMPK/SIRT1 axis in neurodegenerative diseases.

Mesenchymal stem cell therapy in amyotrophic lateral sclerosis (ALS) patients: A comprehensive review of disease information and future perspectives

Amyotrophic lateral sclerosis (ALS) is a rare deadly progressive neurological disease that primarily affects the upper and lower motor neurons with an annual incidence rate of 0.6 to 3.8 per 100,000 people. Weakening and gradual atrophy of the voluntary muscles are the first signs of the disease onset affecting all aspects of patients' lives, including eating, speaking, moving, and even breathing. Only 5-10% of patients have a familial type of the disease and show an autosomal dominant pattern, but the cause of the disease is unknown in the remaining 90% of patients (Sporadic ALS). However, in both types of disease, the patient's survival is 2 to 5 years from the disease onset. Some clinical and molecular biomarkers, magnetic resonance imaging (MRI), blood or urine test, muscle biopsy, and genetic testing are complementary methods for disease diagnosis. Unfortunately, with the exception of Riluzole, the only medically approved drug for the management of this disease, there is still no definitive cure for it. In this regard, the use of mesenchymal stem cells (MSCs) for the treatment or management of the disease has been common in preclinical and clinical studies for many years. MSCs are multipotent cells having immunoregulatory, anti-inflammatory, and differentiation ability that makes them a good candidate for this purpose. This review article aims to discuss multiple aspects of ALS disease and focus on MSCs' role in disease management based on performed clinical trials.

New developments and opportunities in drugs being trialed for amyotrophic lateral sclerosis from 2020 to 2022

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder that primarily affects motor neurons in the brain and spinal cord. In the recent past, there have been just two drugs approved for treatment, riluzole and edaravone, which only prolong survival by a few months. However, there are many novel experimental drugs in development. In this review, we summarize 53 new drugs that have been evaluated in clinical trials from 2020 to 2022, which we have classified into eight mechanistic groups (anti-apoptotic, anti-inflammatory, anti-excitotoxicity, regulated integrated stress response, neurotrophic factors and neuroprotection, anti-aggregation, gene therapy and other). Six were tested in phase 1 studies, 31 were in phase 2 studies, three failed in phase 3 studies and stopped further development, and the remaining 13 drugs were being tested in phase 3 studies, including methylcobalamin, masitinib, MN-166, verdiperstat, memantine, AMX0035, trazodone, CNM-Au8, pridopidine, SLS-005, IONN363, tofersen, and reldesemtiv. Among them, five drugs, including methylcobalamin, masitinib, AMX0035, CNM-Au8, and tofersen, have shown potent therapeutic effects in clinical trials. Recently, AMX0035 has been the third medicine approved by the FDA for the treatment of ALS after riluzole and edaravone.

Chromatographic measurement of 3-hydroxyanthranilate 3,4-dioxygenase activity reveals that edaravone can mitigate the formation of quinolinic acid through a direct enzyme inhibition

Herein it is reported the development and application of two chromatographic assays for the measurement of the activity of 3-Hydroxyanthranilate-3,4-dioxygenase (3HAO). Such an enzyme converts 3-Hydroxyanthranilic acid (3HAA) to 2-amino-3-carboxymuconic semialdehyde (ACMS), which undergo a spontaneous, non-enzymatic cyclization to produce quinolinic acid (QUIN). The enzyme activity was measured by quantitation of the substrate consumption over time either with spectrophotometric (UV) or mass spectrometric (MS) detection upon reversed-phase chromatographic separation. MS detection resulted more selective and sensitive, but less accurate and precise. However, both methods have sufficient sensitivity to allow the measurement of enzyme activity with consistent results compared to literature data. Since MS detection allowed less sample consumption it was used to calculate the kinetics parameters (i.e., Vmax and Kd) of recombinant 3HAO. Another MS-based method was then developed to measure the amount of QUIN produced, revealing an incomplete conversion of 3HAA to QUIN. As suggested by previous studies, the enzyme activity was apparently sensitive to the redox state of the enzyme thiols. In fact, thiol reducing agents such as dithiothreitol (DTT) and glutathione (GSH), can alter the enzyme activity although the investigation on the exact mechanism involved in such effect was beyond the scope of the research. Interestingly, edaravone (EDA) induced an in vitro suppression of QUIN production through direct, competitive 3HAO inhibition. EDA is a molecule approved for the treatment of amyotrophic lateral sclerosis (ALS), a neurodegenerative disease associated with an increase of QUIN concentrations in both serum and cerebrospinal fluid. Although EDA was reported to mitigate ALS progression its mode of action is still largely unknown. Some studies reported antioxidant and radical scavenger properties of EDA, but none confirm a direct activity as 3HAO enzyme inhibitor. Since QUIN is reported to be a neurotoxic metabolite, 3HAO inhibition can contribute to the beneficial effect of EDA in ALS, although such a mechanism must be then confirmed in vivo. However, EDA might be a convenient scaffold for the design of selective 3HAO inhibitors with potential applications in ALS treatment.

Long-term outcomes of edaravone in amyotrophic lateral sclerosis in South Korea: 72-week observational study

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a lethal neurodegenerative disease characterized by the gradual loss of upper and lower motor neurons that leads to progressive muscle atrophy and weakness. Edaravone, a free-radical scavenger, was approved as an ALS treatment in 2015 in South Korea.

METHODS

This study investigated the long-term effects and safety of edaravone by reviewing the medical records of 16 Korean patients with ALS who received extended edaravone between 2015 and 2021 in a single tertiary ALS center.

RESULTS

Among sixteen patients, eleven patients underwent extended edaravone therapy for more than 18 cycles (72 weeks). The mean monthly changes in the revised ALS Functional Rating Scale (ALSFRS-R) were - 0.96 ± 0.83 (0-24 weeks), - 0.70 ± 0.76 (24-48 weeks), - 1.18 ± 1.67 (48-72 weeks), and - 0.81 ± 0.60 (0-72 weeks). The mean decline in forced vital capacity (FVC) was 17.4 ± 24.1. The changes were significant in both ALSFRS-R (p < 0.001) and FVC (p = 0.048); however, the mean change in compound muscle action potential of phrenic nerves was not. Patients experienced only minor adverse events, which were well tolerated.

CONCLUSIONS

This study verifies previous reported outcomes of edaravone in 16 Korean ALS patients, indicating a modest effect with a favorable safety profile.

Analysis of the US Safety Data for Edaravone (Radicava®) From the Third Year After Launch

Background

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neuromuscular disease with no curative therapies. Edaravone (Radicava^®) (Mitsubishi Tanabe Pharma Corporation, Tokyo, Japan), approved in the United States (US) for ALS in adults in 2017, was shown in a clinical trial to slow the rate of physical functional decline in ALS and is administered intravenously. The aim of this paper is to summarize the observed safety profile from real-world patient use during the first 3 years of edaravone availability in the US.

Methods

Edaravone usage data were collected, and adverse events (AEs) were identified from a postmarketing safety database from August 8, 2017 through August 7, 2020 (cutoff date).

Results

As of October 3, 2020, 5207 ALS patients had been treated with edaravone. As of August 7, 2020, the most commonly reported AEs included death (not specified), drug ineffective, disease progression, therapeutic response unexpected, fall, asthenia, fatigue, muscular weakness, gait disturbance, and dyspnea. The most commonly reported serious AEs (SAEs) included death (not specified), pneumonia, disease progression, ALS, fall, dyspnea, respiratory failure, device-related infection, hospitalization, and injection-site infection. There were 687 deaths, with 494 reported as death without specifying the cause. Deaths were most commonly attributed to ALS, disease progression, respiratory failure, or pneumonia. Review for administration-site reactions revealed 95 AEs, including 34 site infections, with 22 SAEs (all non-fatal). Five non-fatal SAEs of anaphylaxis were reported.

Conclusion

In the postmarketing reporting to date, no new safety signals were identified beyond those already known from the edaravone clinical trial program.

Ethnical Disparities in Response to Edaravone in Patients With Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND), is a progressive neurodegenerative disease characterized by the weakness of voluntary muscles due to the loss of motor neurons. Symptoms ultimately culminate in the form of respiratory failure due to the involvement of the diaphragm. Unfortunately, there is no known cure for this disease. Hence, supportive therapy is the only available option in most terminal cases. However, Riluzole and Edaravone (EDA) are the only two known drugs approved by the U.S. Food and Drug Administration (FDA) for treating this condition. In 2017, EDA was approved for the treatment of ALS. It is hypothesized that Riluzole and EDA work via a mechanism involving antioxidants, which nullifies the oxidative stress believed to be involved in ALS. However, most studies in several countries have found a wide range of disparities in the efficacy of this drug. In this review, we aim to summarize the differences in results from epidemiological studies across 10 different countries and hypothesize the potential causes of these differences.

Potential of Cellular Therapy for ALS: Current Strategies and Future Prospects

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive upper and lower motor neuron (MN) degeneration with unclear pathology. The worldwide prevalence of ALS is approximately 4.42 per 100,000 populations, and death occurs within 3-5 years after diagnosis. However, no effective therapeutic modality for ALS is currently available. In recent years, cellular therapy has shown considerable therapeutic potential because it exerts immunomodulatory effects and protects the MN circuit. However, the safety and efficacy of cellular therapy in ALS are still under debate. In this review, we summarize the current progress in cellular therapy for ALS. The underlying mechanism, current clinical trials, and the pros and cons of cellular therapy using different types of cell are discussed. In addition, clinical studies of mesenchymal stem cells (MSCs) in ALS are highlighted. The summarized findings of this review can facilitate the future clinical application of precision medicine using cellular therapy in ALS.

How Molecular Topology Can Help in Amyotrophic Lateral Sclerosis (ALS) Drug Development: A Revolutionary Paradigm for a Merciless Disease

Even if amyotrophic lateral sclerosis is still considered an orphan disease to date, its prevalence among the population is growing fast. Despite the efforts made by researchers and pharmaceutical companies, the cryptic information related to the biological and physiological onset mechanisms, as well as the complexity in identifying specific pharmacological targets, make it almost impossible to find effective treatments. Furthermore, because of complex ethical and economic aspects, it is usually hard to find all the necessary resources when searching for drugs for new orphan diseases. In this context, computational methods, based either on receptors or ligands, share the capability to improve the success rate when searching and selecting potential candidates for further experimentation and, consequently, reduce the number of resources and time taken when delivering a new drug to the market. In the present work, a computational strategy based on Molecular Topology, a mathematical paradigm capable of relating the chemical structure of a molecule to a specific biological or pharmacological property by means of numbers, is presented. The result was the creation of a reliable and accessible tool to help during the early in silico stages in the identification and repositioning of potential hits for ALS treatment, which can also apply to other orphan diseases. Considering that further computational and experimental results will be required for the final identification of viable hits, three linear discriminant equations combined with molecular docking simulations on specific proteins involved in ALS are reported, along with virtual screening of the Drugbank database as a practical example. In this particular case, as reported, a clinical trial has been already started for one of the drugs proposed in the present study.

Evaluation of clinical outcome and safety profile of edaravone in treatment of amyotrophic lateral sclerosis: a 72-week single-center experience

Edaravone is a free radical scavenger that has been recently approved for treatment of Amyotrophic lateral sclerosis (ALS) to delay functional decline. We aim to evaluate edaravone efficacy and safety in ALS patients in the main neurology tertiary center in Kuwait over 72-week period. We conducted a prospective observational cohort study in the main tertiary hospital over 72-week period from July 2018 until January 2020. Patients were assessed at baseline, 24, 48 and 72 weeks of therapy using ALSFRS-R score, MRC sum score, FVC value, among other parameters. Seventeen consecutive patients were evaluated. All patients were assessed at baseline, 24 and 48 weeks, while 9 patients (52.9%) were further assessed at 72 weeks. There was a statistically significant decline of ALSFRS-R at 72 weeks, MRC sum score at 48 and 72 weeks, while the decline in FVC was not statistically significant. Glycosuria was found in only one patient. Our study showed significant functional decline after 1 year of edaravone therapy with preserved respiratory function. The drug had a high level of dissatisfaction among our cohort despite having a high safety profile.

Logistics and safety of edaravone treatment for amyotrophic lateral sclerosis: experience in Argentina

Since 2015, edaravone is the second drug available for the treatment of Amyotrophic lateral sclerosis (ALS). In this study we analyzed the characteristics and experience of ALS patients treated with this new medication in our country. Sixteen ALS patients were treated with edaravone infusions in three ALS clinics. Most of them were male, had a spinal onset of the disease and a definite diagnosis of ALS. Mean age at first infusion was 53.5 years. Since the diagnosis of ALS, delay in starting treatment with edaravone was five times greater than that of riluzole. Edaravone therapy was usually initiated at a health care facility and was followed by domiciliary cycles. Adverse effects and the need of a special catheter for infusion were rare. Access to edaravone through health insurance was possible in only 43.8% of patients. Altogether, treatment access was limited but feasible and edaravone was well tolerated.

Biomolecular Modifications Linked to Oxidative Stress in Amyotrophic Lateral Sclerosis: Determining Promising Biomarkers Related to Oxidative Stress

Reduction–oxidation reactions are essential to cellular homeostasis. Oxidative stress transcends physiological antioxidative system damage to biomolecules, including nucleic acids and proteins, and modifies their structures. Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motor neuron disease. The cells present in the central nervous system, including motor neurons, are vulnerable to oxidative stress. Neurodegeneration has been demonstrated to be caused by oxidative biomolecular modifications. Oxidative stress has been suggested to be involved in the pathogenesis of ALS. Recent progress in research on the underlying mechanisms of oxidative stress in ALS has led to the development of disease-modifying therapies, including edaravone. However, the clinical effects of edaravone remain limited, and ALS is a heretofore incurable disease. The reason for the lack of reliable biomarkers and the precise underlying mechanisms between oxidative stress and ALS remain unclear. As extracellular proteins and RNAs present in body fluids and represent intracellular pathological neurodegenerative processes, extracellular proteins and/or RNAs are predicted to promise diagnosis, prediction of disease course, and therapeutic biomarkers for ALS. Therefore, we aimed to elucidate the underlying mechanisms between oxidative stress and ALS, and promising biomarkers indicating the mechanism to determine whether therapy targeting oxidative stress can be fundamental for ALS.

Pre-Clinical Pharmacokinetic Characterization, Tissue Distribution, and Excretion Studies of Novel Edaravone Oral Prodrug, TEJ-1704

Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) is a free radical scavenger approved for the treatment of amyotrophic lateral sclerosis, a fatal neuromuscular disease. Edaravone is administered as an intravenous infusion over 60 min for several treatment cycles. To ease the burden of patients and caregivers, the oral formulation of edaravone has been developed. The purpose of this study was to evaluate pharmacokinetics and tissue distribution of TEJ-1704, an edaravone oral prodrug, in male Sprague Dawley rats and beagle dogs. Animal experiments were conducted using Sprague Dawley rats and beagle dogs to evaluate pharmacokinetics, tissue distribution, and excretion of TEJ-1704. Blood, tissues, cerebrospinal fluid, urine, and feces samples were collected at designated sampling time after intravenous (IV) or oral (PO) administration of edaravone or TEJ-1704. A modified bioanalysis method was developed to quantify edaravone in samples including plasma, tissues, cerebrospinal fluid, urine, and feces. The bioanalysis method was validated and successfully applied to pharmacokinetics, tissue distribution, and excretion studies of the novel edaravone prodrug. Although plasma C_max of TEJ-1704 was low, groups administered with TEJ-1704 had high AUC_inf, suggesting continuous metabolism of TEJ-1704 into edaravone. Groups treated with TEJ-1704 also showed lower CSF distribution than the control groups. After the administration of TEJ-1704, the majority of edaravone was distributed to the heart, lung, and kidney. It was excreted equally via urine and feces. The pharmacokinetics, tissue distribution, and excretion of TEJ-1704, a novel edaravone oral prodrug, were successfully characterized. Additional studies are needed to fully understand the difference between TEJ-1704 and edaravone and determine the potency of TEJ-1704.

Relationship between statins and the risk of amyotrophic lateral sclerosis: A PRISMA-compliant meta-analysis

OBJECTIVE

Previous studies on overlapping surveillance databases have suggested that statin use was associated with the development of amyotrophic lateral sclerosis (ALS)-like syndrome. However, the association between statin use and ALS incidence has not been clearly elucidated. To further explore this issue, we performed a systemic review and meta-analysis of all available clinical studies on the association between statin use and ALS incidence.

METHODS

A comprehensive database search on PubMed, Embase, Cochrane Library, and SCOPUS was conducted. We included studies up to January 31, 2020 that fulfilled our inclusion and exclusion criteria. Statin use between the ALS and control groups was collected for the meta-analysis.

RESULTS

Three case-control studies and 1 cohort study, that related the risk of ALS to statin use, satisfied the inclusion criteria for the meta-analysis. There was no statistically significant difference in statin use between the ALS and control groups (odds ratio, 0.75 [95% confidence interval, 0.53-1.08]).

CONCLUSION

No definite association was found between statin use and the development of ALS. Further large-scale prospective randomized control studies are necessary to draw definite conclusions.

Improved Long-Term Survival with Edaravone Therapy in Patients with Amyotrophic Lateral Sclerosis: A Retrospective Single-Center Study in Japan

Reports on the long-term survival effect of edaravone, which was approved for the treatment of amyotrophic lateral sclerosis (ALS) in 2015 in Japan, are rare. Herein, we report our retrospective analysis of 45 consecutive patients with ALS who initially visited our hospital between 2013 and 2018. Of these, 22 patients were treated with edaravone for an average duration of 26.6 (range, 2-64) months, whereas the remaining patients were not treated with edaravone and comprised the control group. There were no differences in baseline demographics between the two groups. The primary endpoint was tracheostomy positive-pressure ventilation (TPPV) or death, and the follow-up period ended in December 2020. The survival rate was significantly better in the edaravone group than in the control group based on the Kaplan-Meier analysis, which revealed that the median survival durations were 49 (9-88) and 25 (8-41) months in the edaravone and control groups, respectively (p = 0.001, log-rank test). There were no serious edaravone-associated adverse effects during the study period. Overall, the findings of this single-center retrospective study suggest that edaravone might prolong survival in patients with ALS.

Renal function in amyotrophic lateral sclerosis patients on long-term treatment with edaravone

Edaravone, a free radical-scavenger, was approved in Japan for the treatment of amyotrophic lateral sclerosis (ALS). However, the effect of the drug on renal function in ALS patients remains unclear. This study aimed to investigate renal function in ALS patients on long-term treatment with edaravone by measuring the serum estimated glomerular filtration rate based on cystatin C (eGFR-CysC).In a retrospective study, the data of ALS patients who were treated with over 10 cycles of intravenous edaravone treatment and were evaluated by eGFR-CysC before and after 10 cycles of treatment between July 2015 and June 2018 were analyzed. Then, the results were compared with those of a control ALS group that had never been treated with edaravone.There were 11 patients with ALS who received over 10 cycles of intravenous edaravone treatment. The mean interval between the first and final eGFR-CysC measurements was 18.7 ± 7.9 months. Three patients (27.3%) had >20 mL/min/1.73 m2 decrease in serum eGFR-CysC. However, no patients discontinued edaravone treatment because of renal dysfunction. The average variation rate of eGFR-CysC was not different between the long-term edaravone group (0.29 ± 1.07) and the control group (-0.34 ± 0.40).This retrospective, single-center analysis showed no clinical exacerbation of renal function in ALS patients who received long-term treatment with edaravone.

Drug Repurposing: Promises of Edaravone Target Drug in Traumatic Brain Injury

Edaravone is a potent free-radical scavenger that has been in the market for more than 30 years. It was originally developed in Japan to treat strokes and has been used there since 2001. Aside from its anti-oxidative effects, edaravone demonstrated beneficial effects on proinflammatory responses, nitric oxide production, and apoptotic cell death. Interestingly, edaravone has shown neuroprotective effects in several animal models of diseases other than stroke. In particular, edaravone administration was found to be effective in halting amyotrophic lateral sclerosis (ALS) progression during the early stages. Accordingly, after its success in Phase III clinical studies, edaravone has been approved by the FDA as a treatment for ALS patients. Considering its promises in neurological disorders and its safety in patients, edaravone is a drug of interest that can be repurposed for traumatic brain injury (TBI) treatment. Drug repurposing is a novel approach in drug development that identifies drugs for purposes other than their original indication. This review presents the biochemical properties of edaravone along with its effects on several neurological disorders in the hope that it can be adopted for treating TBI patients.

Role of Edaravone as a Treatment Option for Patients with Amyotrophic Lateral Sclerosis

Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig's disease, is a progressive and fatal neurodegenerative disease that leads to a loss of muscle control due to nerve cells being affected in the brain and spinal cord. Some of the common clinical presentations of ALS include weakness of muscles, changes in behavior, dysfunction in speech, and cognitive difficulties. The cause of ALS is uncertain, but through several studies, it is known that mutations in SOD1 or C9orf72 genes could play a role as a factor of ALS. In addition, studies indicate that an excessive amount of free radicals, the reactive oxygen species (ROS), leads to neuronal damage by the peroxidation of unsaturated fatty acids in the neuronal cells. Edaravone, the newly approved antioxidant drug for ALS, halts the progression of ALS in the early stages through its cytoprotective effect and protects the nerves by reducing ROS. In this review, different aspects of ALS will be discussed, including its pathology, genetic aspect, and diagnosis. This review also focuses on edaravone as a treatment option for ALS, its mechanism of action, and its pharmacological properties. Clinical trials and adverse effects of edaravone and care for ALS patient are also discussed.

Depression following traumatic brain injury: a comprehensive overview

Traumatic brain injury (TBI) represents a major health concern affecting the neuropsychological health; TBI is accompanied by drastic long-term adverse complications that can influence many aspects of the life of affected individuals. A substantial number of studies have shown that mood disorders, particularly depression, are the most frequent complications encountered in individuals with TBI. Post-traumatic depression (P-TD) is present in approximately 30% of individuals with TBI, with the majority of individuals experiencing symptoms of depression during the first year following head injury. To date, the mechanisms of P-TD are far from being fully understood, and effective treatments that completely halt this condition are still lacking. The aim of this review is to outline the current state of knowledge on the prevalence and risk factors of P-TD, to discuss the accompanying brain changes at the anatomical, molecular and functional levels, and to discuss current approaches used for the treatment of P-TD.

Post-Marketing Experience of Edaravone in Amyotrophic Lateral Sclerosis: A Clinical Perspective and Comparison With the Clinical Trials of the Drug

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disease that affects the upper and lower motor neurons. Currently, the only treatment for ALS is riluzole, which only has a limited effect on increasing survival from 3 to 6 months. New therapies are needed in the clinical setting for ALS. We aim to compare and contrast the clinical trials of edaravone and the post-marketing experience of the drug during this study. For the method, a search strategy was made using PubMed with the search terms "Amyotrophic lateral sclerosis" (MeSH) and "Edaravone" (MeSH). For inclusion criteria, we used full papers, studies involving humans, and studies published in the English language. We exclude meta-analyses, literature reviews, systematic reviews, studies involving animals, and studies not published in English. After close examination, 20 papers were used for the discussion in this review. The clinical trials showed efficacy in patients in reducing the revised ALS functional rating scale (ALSFRS-R) in patients with early ALS with selective criteria. We documented edaravone's post-marketing experience in six countries: Kuwait, South Korea, Argentina, United States, Israel, and Italy. During the study we analyzed, the forced vital capacity (FVC) and ALSFRS-R scored, together with edaravone's safety in the clinical trials and post-marketing experience. Edaravone seems to be more effective in Asia, where the ALSFRS-R scores and the FVC decline were similar to the clinical trial results in Japan. Studies in Europe did not find the drug clinically useful. At the same time, studies in United States and Argentina were mainly descriptive, so more information is needed to evaluate the drug's efficacy in that part of the world. The drug was well-tolerated in all studies. In conclusion, more studies need to be done worldwide to carry out and clarify the effectiveness of edaravone in the clinical setting.

Assessment of Use and Safety of Edaravone for Amyotrophic Lateral Sclerosis in the Veterans Affairs Health Care System

IMPORTANCE

Using real-world data, the US Department of Veterans Affairs (VA) initiated a surveillance evaluation of edaravone after its approval for amyotrophic lateral sclerosis (ALS) in 2017. The use and safety of edaravone for patients with ALS in the VA health care system remain to be assessed.

OBJECTIVE

To describe a pharmacovigilance surveillance initiative with edaravone to monitor patient characteristics, utilization (edaravone cycles and riluzole use), and safety and to evaluate safety/effectiveness.

DESIGN, SETTING, AND PARTICIPANTS

This propensity score-matched cohort study used data on 369 patients with documented definite or probable ALS in the Veterans Health Administration (VHA) with at least 1 prescription for edaravone between August 1, 2017, and September 30, 2019. The analysis compared edaravone (alone or with riluzole) with riluzole only. For chronic users (≥6 months of drug), a time-to-event model evaluated ALS-related outcomes, with censoring at outcome, death, or end of evaluation. Patients with Parkinson disease, dementia, schizophrenia, or significant respiratory insufficiency per diagnosis codes within 2 years before prescription initiation were excluded. In overall matched cohorts, 223 patients treated with edaravone were 1:3 propensity score matched based on predefined confounders. For the chronic user subgroup analysis, 96 patients receiving edaravone and 424 patients receiving riluzole only were included.

EXPOSURES

Edaravone (alone or with riluzole) vs riluzole only.

MAIN OUTCOMES AND MEASURES

Patient characteristics, ALS drug use, and mortality. Acute outcomes (within 6 months of index) included proportion and mean time to event for death, discontinuation, or all-cause hospitalization, and outcomes for chronic users (receiving >6 months of treatment) included hazard ratios of outcomes related to disease-state progression.

RESULTS

Of 369 patients who received edaravone, most were older (mean [SD] age, 64.6 [11.3] years), male (346 [93.8%]), and White (261 [70.7%]). As of September 2019, 59.9% of edaravone patients had discontinued treatment; of those, 49.5% (108 of 218) received only 1 to 3 treatment cycles. Approximately 30% (110 patients) died. In a matched evaluation, significantly more acute all-cause hospitalization events occurred with edaravone (35.4% vs 22.0% for riluzole only); 72.6% of the edaravone cohort received edaravone with riluzole. Among chronic users, edaravone patients (70.8% edaravone with riluzole) had an increased hazard ratio of ALS-associated hospitalization (2.51; 95% CI, 1.18-8.16). The death rate was lower with edaravone but the difference was not statistically significant.

CONCLUSIONS AND RELEVANCE

Early edaravone discontinuation was common in the VA. Although outcomes favored use of riluzole only in the matched analysis, results should be interpreted with caution, as unmeasured bias in observational data is likely.

PET Imaging for Oxidative Stress in Neurodegenerative Disorders Associated with Mitochondrial Dysfunction

Oxidative stress based on mitochondrial dysfunction is assumed to be the principal molecular mechanism for the pathogenesis of many neurodegenerative disorders. However, the effects of oxidative stress on the neurodegeneration process in living patients remain to be elucidated. Molecular imaging with positron emission tomography (PET) can directly evaluate subtle biological changes, including the redox status. The present review focuses on recent advances in PET imaging for oxidative stress, in particular the use of the Cu-ATSM radioligand, in neurodegenerative disorders associated with mitochondrial dysfunction. Since reactive oxygen species are mostly generated by leakage of excess electrons from an over-reductive state due to mitochondrial respiratory chain impairment, PET with ⁶²Cu-ATSM, the accumulation of which depends on an over-reductive state, is able to image oxidative stress. ⁶²Cu-ATSM PET studies demonstrated enhanced oxidative stress in the disease-related brain regions of patients with mitochondrial disease, Parkinson’s disease, and amyotrophic lateral sclerosis. Furthermore, the magnitude of oxidative stress increased with disease severity, indicating that oxidative stress based on mitochondrial dysfunction contributes to promoting neurodegeneration in these diseases. Oxidative stress imaging has improved our insights into the pathological mechanisms of neurodegenerative disorders, and is a promising tool for monitoring further antioxidant therapies.

Validation of the revised Amyotrophic Lateral Sclerosis Functional Rating Scale in Poland and its reliability in conditions of the medical experiment

Introduction

Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) is a basic tool for monitoring disease progression in amyotrophic lateral sclerosis (ALS). This study analyses the reliability of the Polish version of the ALSFRS-R as a tool to assess the health condition of patients with ALS and presents experience related to the use of this tool in monitoring the effects of experimental medical therapy.

Materials and methods

The scale questionnaire was translated using the cross-translation method. The final tool was used by researcher, who was conducting the interview directly by telephone with patients and their caregivers and additionally compared with neurologopedic measurement. The health status of 60 patients was assessed between 4 and 7 times, which gives a total of 327 observations. Mean patient’s age was 57.5 ± 8.6. The division by sex was 23/35 (female/male). Patients’ health status and severity of symptoms varied. Statistical analysis was performed using explanatory factor analysis and Cronbach’s alpha.

Result

Validation of the Polish version of the ALSFRS-R supports the reliability and internal consistency of scale. The scale proved also to be a proper tool for monitoring the course of the experimental medical therapy for patients with ALS. However, a qualitative evaluation revealed certain weaknesses of the scale, resulting from a different understanding of the functional assessment by the patient and by the medical specialist and cultural differences.

Discussion

Although ALSFRS-R is a reliable enough for monitoring patient health, it seems reasonable to pay attention to some difficult points of the questionnaire and its improvement.

Electronic supplementary material

The online version of this article (10.1007/s10072-020-04565-5) contains supplementary material, which is available to authorized users.

The Italian multicenter experience with edaravone in amyotrophic lateral sclerosis

OBJECTIVES

The aim of the study is to analyze the ALS disease progression and respiratory function of Italian patients treated with edaravone (EVN), as well as the adherence to, and the effects of, the therapy.

METHODS

We performed an observational study of patients treated with EVN from May 2017 to May 2019, in 39 Italian ALS Centers. Taking into account ALS patients with at least 12 months of EVN treatment, we compared the decline of ALSFRS-R and FVC with a group of matched historical controls from the Pooled Resource Open-Access ALS Clinical Trials (PRO-ACT) database, using both descriptive and survival analysis approaches.

RESULTS

A total of 331 ALS Italian patients treated with EVN and 290 matched historical controls were recruited in this study. No significant differences on disease progression or respiratory function were found comparing the two cohorts in both descriptive and survival analyses. The EVN treatment was overall well tolerated.

CONCLUSIONS

The study showed that EVN treatment was well tolerated. No significant differences were reported in ALS patients treated and not treated with EVN, in terms of both disease progression and respiratory function. These findings prove that further studies are required to better clarify whether EVN could be considered an effective treatment for ALS disease.

Emerging Drugs for the Treatment of Amyotrophic Lateral Sclerosis: A Focus on Recent Phase 2 Trials

INTRODUCTION

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disease involving both upper and lower motor neurons and resulting in increasing disability and death 3-5 years after onset of symptoms. Over 40 large clinical trials for ALS have been negative, except for Riluzole that offers a modest survival benefit, and Edaravone that modestly reduces disease progression in patients with specific characteristics. Thus, the discovery of efficient disease modifying therapy is an urgent need.

AREAS COVERED

Although the cause of ALS remains unclear, many studies have demonstrated that neuroinflammation, proteinopathies, glutamate-induced excitotoxicity, microglial activation, oxidative stress, and mitochondrial dysfunction may play a key role in the pathogenesis. This review highlights recent discoveries relating to these diverse mechanisms and their implications for the development of therapy. Ongoing phase 2 clinical trials aimed to interfere with these pathophysiological mechanisms are discussed.

EXPERT OPINION

This review describes the challenges that the discovery of an efficient drug therapy faces and how these issues may be addressed. With the continuous advances coming from basic research, we provided possible suggestions that may be considered to improve performance of clinical trials and turn ALS research into a 'fertile ground' for drug development for this devastating disease.