Treatment of spinocerebellar ataxia with buspirone

Multi-omic insights into molecular mechanism and therapeutic targets in spinocerebellar ataxia type 7

Recent advances in molecular science have significantly enlightened our mechanistic understanding of spinocerebellar ataxia type 7. To further close remaining gaps, we performed a multi-omics analysis using SCA7266Q/5Q mice. Entire brain tissue samples were collected from 12-week-old mice, and RNA sequencing, methylation analysis, and proteomic analysis were performed. Results were integrated to identify genes with identical trends in expression across all three analyses. Data from RNA sequencing and methylation analysis revealed 58 significantly hypomethylated-upregulated genes and 62 hypermethylated-downregulated genes, mostly enriched in GO terms of regulation of axonogenesis, channel activity, and monoamine signaling. In the proteomic analysis, 211 upregulated and 281 downregulated DEPs associated mostly with immune response and cellular mobility were identified. Two genes, Fam107b and Tph2, showed differential expressions in both transcriptomic and proteomic analyses. Findings were validated in RT-qPCR as well as open data source analysis. Our study is the first to perform multi-omics analysis in SCA7 mice and will serve as an important reference for future studies.

Pharmacotherapy for the management of the symptoms of Machado-Joseph Disease

INTRODUCTION

Machado-Joseph disease or spinocerebellar ataxia type 3 (SCA3/MJD) is the leading cause of autosomal dominant ataxia worldwide. This is a slowly progressive, but very disabling disorder. Ataxia is the main clinical feature, but additional motor and non-motor manifestations may be found. Many of these manifestations are amenable to pharmacological treatments, which may impact the quality of life of affected subjects.

AREAS COVERED

Authors review available literature on both disease-modifying and symptomatic pharmacological therapies for SCA3/MJD. Discussion is stratified into motor (ataxic and non-ataxic syndromes) and non-motor manifestations. Ongoing clinical trials and future perspectives are also discussed in the manuscript.

EXPERT OPINION

Symptomatic treatment is the mainstay of clinical care and should be tailored for each patient with SCA3/MJD. Management of ataxia is still a challenging task, but relief (at least partial) of dystonia, pain/cramps, fatigue, and sleep disorders is an achievable goal for many patients. Even though there are no disease-modifying treatments so far, recent advances in understanding the biology of disease and international collaborations of clinical researchers are now paving the way for a new era where more clinical trials will be available for this devastating disorder.

Current and Emerging Treatment Modalities for Spinocerebellar Ataxias

INTRODUCTION

Spinocerebellar ataxias (SCA) are a group of rare neurodegenerative diseases that dramatically affect the lives of affected individuals and their families. Despite having a clear understanding of SCA's etiology, there are no current symptomatic or neuroprotective treatments approved by the FDA.

AREAS COVERED

Research efforts have greatly expanded the possibilities for potential treatments, including both pharmacological and non-pharmacological interventions. Great attention is also being given to novel therapeutics based in gene therapy, neurostimulation, and molecular targeting. This review article will address the current advances in the treatment of SCA and what potential interventions are on the horizon.

EXPERT OPINION

SCA is a highly complex and multifaceted disease family with the majority of research emphasizing symptomatic pharmacologic therapies. As pre-clinical trials for SCA and clinical trials for other neurodegenerative conditions illuminate the efficacy of disease modifying therapies such as AAV-mediated gene therapy and ASOs, the potential for addressing SCA at the pre-symptomatic stage is increasingly promising.

Placebo response in degenerative cerebellar ataxias: a descriptive review of randomized, placebo-controlled trials

Placebo response in degenerative cerebellar ataxias (CAs) has never been studied despite the large number of randomized controlled trials (RCTs) that have been conducted. In this descriptive review, we aimed to examine the placebo response in patients with CAs. We performed a literature search on PubMed for RCTs on CAs that were published from 1977 to January 2020 and collected data on the changes from the baseline to the endpoint on various objective ataxia-associated clinical rating scales. We reviewed 56 clinical trials, finally including 35 parallel-group studies and excluding 21 cross-over studies. The included studies were categorized as follows: (1) studies showing significant improvements in one or more ataxia scales in the placebo groups (n = 3); (2) studies reporting individual placebo responders with improvements in one or more ataxia scales in the placebo groups (n = 5)-the overall proportion of placebo responders was 31.9%; (3) studies showing mean changes in the direction of improvement in at least one ataxia scale in the placebo groups, though not statistically significant (n = 19); (4) studies showing no placebo response in any of the ataxia scales in the placebo groups (n = 4); (5) studies where data on the placebo groups were unavailable (n = 9). This review demonstrated the placebo response in patients with CAs on various objective ataxia scales. Our study emphasizes that the placebo response should be considered when designing, analyzing, and interpreting clinical trials and in clinical practice in CA patients.

What is the best way to keep walking and moving around for individuals with Machado-Joseph disease? A scoping review through the lens of Aboriginal families with Machado-Joseph disease in the Top End of Australia

OBJECTIVES

Machado-Joseph disease (MJD) is the most common spinocerebellar ataxia worldwide. Prevalence is highest in affected remote Aboriginal communities of the Top End of Australia. Aboriginal families with MJD from Groote Eylandt believe 'staying strong on the inside and outside' works best to keep them walking and moving around, in accordance with six key domains that form the 'Staying Strong' Framework. The aim of this current study was to review the literature to: (1) map the range of interventions/strategies that have been explored to promote walking and moving around (functional mobility) for individuals with MJD and; (2) align these interventions to the 'Staying Strong' Framework described by Aboriginal families with MJD.

DESIGN

Scoping review.

DATA SOURCES

Searches were conducted in July 2018 in MEDLINE, EMBASE, CINAHL, PsychINFO and Cochrane Databases.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Peer-reviewed studies that (1) included adolescents/adults with MJD, (2) explored the effects of any intervention on mobility and (3) included a measure of mobility, function and/or ataxia were included in the review.

RESULTS

Thirty studies were included. Few studies involved participants with MJD alone (12/30). Most studies explored interventions that aligned with two 'Staying Strong' Framework domains, 'exercising your body' (n=13) and 'searching for good medicine' (n=17). Few studies aligned with the domains having 'something important to do' (n=2) or 'keeping yourself happy' (n=2). No studies aligned with the domains 'going country' or 'families helping each other'.

CONCLUSIONS

Evidence for interventions to promote mobility that align with the 'Staying Strong' Framework were focused on staying strong on the outside (physically) with little reflection on staying strong on the inside (emotionally, mentally and spiritually). Findings suggest future research is required to investigate the benefits of lifestyle activity programmes that address both physical and psychosocial well-being for families with MJD.

Comprehensive systematic review summary: Treatment of cerebellar motor dysfunction and ataxia: Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology

OBJECTIVE

To systematically review evidence regarding ataxia treatment.

METHODS

A comprehensive systematic review was performed according to American Academy of Neurology methodology.

CONCLUSIONS

For patients with episodic ataxia type 2, 4-aminopyridine 15 mg/d probably reduces ataxia attack frequency over 3 months (1 Class I study). For patients with ataxia of mixed etiology, riluzole probably improves ataxia signs at 8 weeks (1 Class I study). For patients with Friedreich ataxia or spinocerebellar ataxia (SCA), riluzole probably improves ataxia signs at 12 months (1 Class I study). For patients with SCA type 3, valproic acid 1,200 mg/d possibly improves ataxia at 12 weeks. For patients with spinocerebellar degeneration, thyrotropin-releasing hormone possibly improves some ataxia signs over 10 to 14 days (1 Class II study). For patients with SCA type 3 who are ambulatory, lithium probably does not improve signs of ataxia over 48 weeks (1 Class I study). For patients with Friedreich ataxia, deferiprone possibly worsens ataxia signs over 6 months (1 Class II study). Data are insufficient to support or refute the use of numerous agents. For nonpharmacologic options, in patients with degenerative ataxias, 4-week inpatient rehabilitation probably improves ataxia and function (1 Class I study); transcranial magnetic stimulation possibly improves cerebellar motor signs at 21 days (1 Class II study). For patients with multiple sclerosis-associated ataxia, the addition of pressure splints possibly has no additional benefit compared with neuromuscular rehabilitation alone (1 Class II study). Data are insufficient to support or refute use of stochastic whole-body vibration therapy (1 Class III study).

Current concepts in the treatment of hereditary ataxias

Hereditary ataxias (HA) represents an extensive group of clinically and genetically heterogeneous neurodegenerative diseases, characterized by progressive ataxia combined with extra-cerebellar and multi-systemic involvements, including peripheral neuropathy, pyramidal signs, movement disorders, seizures, and cognitive dysfunction. There is no effective treatment for HA, and management remains supportive and symptomatic. In this review, we will focus on the symptomatic treatment of the main autosomal recessive ataxias, autosomal dominant ataxias, X-linked cerebellar ataxias and mitochondrial ataxias. We describe management for different clinical symptoms, mechanism-based approaches, rehabilitation therapy, disease modifying therapy, future clinical trials and perspectives, genetic counseling and preimplantation genetic diagnosis.

Treatment for speech disorder in Friedreich ataxia and other hereditary ataxia syndromes

BACKGROUND

Hereditary ataxia syndromes can result in significant speech impairment, a symptom thought to be responsive to treatment. The type of speech impairment most commonly reported in hereditary ataxias is dysarthria. Dysarthria is a collective term referring to a group of movement disorders affecting the muscular control of speech. Dysarthria affects the ability of individuals to communicate and to participate in society. This in turn reduces quality of life. Given the harmful impact of speech disorder on a person's functioning, treatment of speech impairment in these conditions is important and evidence-based interventions are needed.

OBJECTIVES

To assess the effects of interventions for speech disorder in adults and children with Friedreich ataxia and other hereditary ataxias.

SEARCH METHODS

On 14 October 2013, we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, CINAHL Plus, PsycINFO, Education Resources Information Center (ERIC), Linguistics and Language Behavior Abstracts (LLBA), Dissertation Abstracts and trials registries. We checked all references in the identified trials to identify any additional published data.

SELECTION CRITERIA

We considered for inclusion randomised controlled trials (RCTs) or quasi-RCTs that compared treatments for hereditary ataxias with no treatment, placebo or another treatment or combination of treatments, where investigators measured speech production.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted data and assessed the risk of bias of included studies using the standard methodological procedures expected by The Cochrane Collaboration. The review authors collected information on adverse effects from included studies. We did not conduct a meta-analysis as no two studies utilised the same assessment procedures within the same treatment.

MAIN RESULTS

Fourteen clinical trials, involving 721 participants, met the criteria for inclusion in the review. Thirteen studies compared a pharmaceutical treatment with placebo (or a low dose of the intervention), in heterogenous groups of degenerative cerebellar ataxias. Three compounds were studied in two trials each: a levorotatory form of 5-hydroxytryptophan (L-5HT), idebenone and thyrotropin-releasing hormone tartrate (TRH-T); each of the other compounds (riluzole, varenicline, buspirone, betamethasone, coenzyme Q10 with vitamin E, α-tocopheryl quinone and erythropoietin) were studied in one trial. The 14th trial, involving a mixed group of participants with spinocerebellar ataxia, compared the effectiveness of nonspecific physiotherapy and occupational therapy within an inpatient hospital setting to no treatment. No studies utilised traditional speech therapies. We defined the primary outcome measure in this review as the percentage change (improvement) in overall speech production immediately following completion of the intervention or later, measured by any validated speech assessment tool. None of the trials included speech as a primary outcome or examined speech using any validated speech assessment tool. Eleven studies reported speech outcomes derived from a subscale embedded within disease rating scales. The remaining three studies used alternative assessments to measure speech, including mean time to produce a standard sentence, a subjective rating of speech on a 14-point analogue scale, patient-reported assessment of the impact of dysarthria on activities of daily living and acoustic measures of syllable length. One study measured speech both subjectively as part of a disease rating scale and with further measures of speech timing. Three studies utilised the Short Form-36 Health Survey (SF-36) and one used the Child Health Questionnaire as measures of general quality of life. A further study utilised the Functional Independence Measure to assess functional health.Five studies reported statistically significant improvement on an overall disease rating scale in which a speech subscale was included. Only three of those studies provided specific data on speech performance; all were comparisons with placebo. Improvements in overall disease severity were observed with α-tocopheryl quinone; however, no significant changes were found on the speech subscale in a group of individuals with Friedreich ataxia. A statistically significant improvement in speech according to a speech disorders subscale was observed with betamethasone. Riluzole was found to have a statistically significant effect on speech in a group of participants with mixed hereditary, sporadic and unknown origin ataxias. No significant differences were observed between treatment and placebo in any other pharmaceutical study. A statistically significant improvement in functional independence occurred at the end of the treatment period in the rehabilitation study compared to the delayed treatment group but these effects were not present 12 to 24 weeks after treatment. Of the four studies that assessed quality of life, none found a significant effect. A variety of minor adverse events were reported for the 13 pharmaceutical therapies, including gastrointestinal side effects and nausea. Serious adverse effects were reported in two participants in one of the L-5HT trials (participants discontinued due to gastrointestinal effects), and in four participants (three taking idebenone, one taking placebo) in the idebenone studies. Serious adverse events with idebenone were gastrointestinal side effects and, in people with a previous history of these events, chest pain and idiopathic thrombocytopenic purpura. The rehabilitation study did not report any adverse events.We considered six studies to be at high risk of bias in some respect. We suspected inadequate blinding of participants or assessors in four studies and poor randomisation in a further two studies. There was a high risk of reporting bias in two studies and attrition bias in four studies. Only one study had a low risk of bias across all criteria. Taken together with other limitations of the studies relating to the validity of the measurement scales used, we downgraded the quality of the evidence for many of the outcomes to low or very low.

AUTHORS' CONCLUSIONS

There is insufficient and low or very low quality evidence from either RCTs or observational studies to determine the effectiveness of any treatment for speech disorder in any of the hereditary ataxia syndromes.

Treatment of cerebellar ataxia

SUMMARY 

Symptoms of cerebellar degeneration include ataxia or wide-based gait, visual and speech dysfunction, dysmetria, and dyscoordination. The etiology of cerebellar degeneration is vast and often complex, and requires neuroimaging, lab assessments, and a thorough family history to delineate its cause. There is currently no accepted treatment of hereditary cerebellar degeneration, although several pharmaceutical agents have shown potential promise.

Consensus paper: management of degenerative cerebellar disorders

Treatment of motor symptoms of degenerative cerebellar ataxia remains difficult. Yet there are recent developments that are likely to lead to significant improvements in the future. Most desirable would be a causative treatment of the underlying cerebellar disease. This is currently available only for a very small subset of cerebellar ataxias with known metabolic dysfunction. However, increasing knowledge of the pathophysiology of hereditary ataxia should lead to an increasing number of medically sensible drug trials. In this paper, data from recent drug trials in patients with recessive and dominant cerebellar ataxias will be summarized. There is consensus that up to date, no medication has been proven effective. Aminopyridines and acetazolamide are the only exception, which are beneficial in patients with episodic ataxia type 2. Aminopyridines are also effective in a subset of patients presenting with downbeat nystagmus. As such, all authors agreed that the mainstays of treatment of degenerative cerebellar ataxia are currently physiotherapy, occupational therapy, and speech therapy. For many years, well-controlled rehabilitation studies in patients with cerebellar ataxia were lacking. Data of recently published studies show that coordinative training improves motor function in both adult and juvenile patients with cerebellar degeneration. Given the well-known contribution of the cerebellum to motor learning, possible mechanisms underlying improvement will be outlined. There is consensus that evidence-based guidelines for the physiotherapy of degenerative cerebellar ataxia need to be developed. Future developments in physiotherapeutical interventions will be discussed including application of non-invasive brain stimulation.

Treatment Options in Degenerative Cerebellar Ataxia: A Systematic Review

The etiology of cerebellar ataxia (CA) is heterogeneous and includes easily identified and often reversible causes (i.e., drug toxicity and vitamin B12 deficiency) as well as irreversible degenerative conditions. It is the latter that poses a significant therapeutic challenge for practitioners treating this population of patients. To date, there are no U.S. Food and Drug Administration-approved medications for the treatment of CA. The literature, consisting mostly of case reports, case series, and small clinical trials, is sparse and scattered. These studies are difficult to translate clinically because they often describe diverse study populations with various identified and unidentified genetic etiologies. In addition, the reported treatment duration is often brief, and it is uncertain whether any of these options provide substantially lasting benefits. In this article, we review published reports and studies to aid the practitioner counseling patients with degenerative ataxias.

Assessing the efficacy of specific cerebellomodulatory drugs for use as therapy for spinocerebellar ataxia type 1

Spinocerebellar ataxias are autosomal dominant diseases, associated in some types with a CAG repeat expansion, and characterised by a progressive loss of motor function. Currently, as there is no cure for most ataxias, treatment predominantly involves physical therapy. Various symptomatic drug treatments have been tried; however, published clinical studies have provided inconsistent results, likely due to small sample sizes, mixed patient populations and insensitive or subjective assessment scales. SCA1(154Q) transgenic mice display motor function impairments and ultimately a reduced number of cerebellar Purkinje neurons-characteristics comparable to most forms of sporadic and hereditary ataxias. We monitored motor function in SCA1(154Q) mice from 5 to 20 weeks of age and assessed the efficacy of four potential cerebellar modulatory drugs in attenuating deficits in rotor-rod performance. The drugs riluzole, amantadine, zolpidem and buspirone were selected based on their different mechanisms of action and their Food and Drug Administration (FDA)/Australian Therapeutic Goods Administration approval for other indications. SCA1(154Q) and C57/Bl6 wild-type mice were administered with four ascending acute doses of each drug, over 2 days. Following each dose, mice were assesed for motor function on the accelerating rotor-rod. None of the four drugs attenuated motor deficts in SCA1(154Q) mice at any dose; at FDA equivalent and higher dose administration of zolpidem and buspirone led to sedation in both strains. Our results suggest that the aforementioned drugs are likely to be ineffective for symptomatic treatment of SCA1 and most other ataxic patients and emphasise the need for comphrehensive drug studies prior to clinical use.

Treatment of imbalance with varenicline Chantix(R): report of a patient with fragile X tremor/ataxia syndrome

We describe the case of a man with Fragile X tremor/ataxia syndrome, whose ataxia and imbalance improved with the use of varenicline (Chantix) and reverted to baseline 10 days after varenicline was discontinued. Varenicline was started as part of a smoking cessation program.

Validating an Ataxia Functional Composite Scale in spinocerebellar ataxia

The Ataxia Functional Composite Scale (AFCS) may provide a sensitive and reproducible assessment of treatment responses in studies of the spinocerebellar ataxias (SCA). We previously assessed the effects of buspirone in a cohort of patients with SCA via the International Cooperative Ataxia Rating Scale (ICARS). At each assessment period, AFCS scores were also obtained. A strong correlation of AFCS with ICARS scores was demonstrated at all assessment periods. This study supports the validity of the AFCS as a useful assessment of ataxia in this population.