A phase II-III trial of olesoxime in subjects with amyotrophic lateral sclerosis

BACKGROUND AND PURPOSE

To assess the efficacy and safety of olesoxime, a molecule with neuroprotective properties, in patients with amyotrophic lateral sclerosis (ALS) treated with riluzole.

METHODS

A double-blind, randomized, placebo-controlled, multicenter trial of 18 months' duration was conducted in 512 subjects, with probable or definite ALS and a slow vital capacity (SVC) ≥70%, receiving 330 mg olesoxime daily or matching placebo and 50 mg riluzole twice a day in all. The primary intention-to-treat (ITT) outcome analysis was 18 months' survival. Secondary outcomes were rates of deterioration of the revised ALS functional rating scale (ALSFRS-R), focusing on the 9-month assessment, SVC and manual muscle testing. Blood levels, safety and tolerability of olesoxime were also assessed.

RESULTS

At 18 months, 154 of the 512 ITT patients had died (79 of 253 placebo, 75 of 259 olesoxime). Estimated overall survival according to Kaplan-Meier analysis was 67.5% (95% CI 61.0%-73.1%) in the placebo group and 69.4% (95% CI 63.0%-74.9%) in the olesoxime group; hence survival was not significantly different between treatment arms (P = 0.71, stratified bulbar/spinal log-rank). The other efficacy end-points evaluated were also negative, with the exception of a small difference in ALSFRS-R global score at 9 months in favor of olesoxime but not sustained after 18 months' treatment nor evident in either the stratified bulbar or spinal subpopulations. Treatment did not raise any safety concerns.

CONCLUSIONS

Olesoxime, although well tolerated, did not show a significant beneficial effect in ALS patients treated with riluzole.

[Analysis of clinical pathway in changing and disabling neurological diseases]

Neurological diseases are characterized by the complexity of care and by a constant and changing disability. More and more frequently, their impact on the clinical pathway remains unknown. Seven postgraduate rehabilitation students (Master coordination du handicap, université Pierre-et-Marie-Curie, Paris) reconstructed the clinical pathway of 123 patients with various neurological diseases: multiple sclerosis, Alzheimer disease, amyotrophic lateral sclerosis, spinal trauma, Parkinson disease and brain tumors. There was a significant correlation between disease duration and the number of specialists involved in care, the number of prescribed drugs and the number of short-term hospitalizations; there was no correlation with age. This result suggests that with time an increasing number of complications related to the initial neurological disease developed. Hospitalization in rehabilitation units was highly correlated with the degree of disability and also with the help received by the patients during the course of their disease. This result suggests that these hospitalizations were a direct consequence of burn out among relatives. General practitioners (GP) were highly involved only during the initial part of the pathway, and their involvement rapidly declined thereafter, suggesting a probable relation with the specificities and the complexity of care for neurological diseases which induces a progressive transfer of responsibilities from the GP to the hospital. Social care was always incomplete and occurred too late during the course of the disease. The feeling by the patients that their care pathway was chaotic was highly correlated with the quality of the information given to the patient at the time of the announcement of their disease. This study confirms that cares for neurological diseases is highly specific and that expert centers and coordination networks are in a key position to ensure an efficient care pathway.

Genotype-phenotype relationship in 2 SMA III patients with novel mutations in the Tudor domain

OBJECTIVE

We report the cases of 2 patients with late-onset spinal muscular atrophy (SMA) type III, who were hemizygous for SMN1 deletion and carriers of novel SMN1 intragenic missense mutations, and we investigate the genotype-phenotype relationship.

METHODS

Patients were tested for SMN1 deletions with standard methodology. Sequencing of all exons, exon-intron junctions, and flanking sequences of SMN1 by nested PCR was used to detect intragenic point mutations. SMN1 and SMN2 quantification was undertaken to investigate the genotype-phenotype relationship.

RESULTS

Two novel point mutations were identified in exon 3 of SMN1 (p.Tyr130Cys and p.Tyr130His) in the highly conserved Tudor domain of the Smn protein.

CONCLUSIONS

The genetic basis of SMA in the rare cases of compound heterozygous carriers of SMN1 deletions is complex. Small intragenic SMN1 mutations often lead to severe SMA phenotypes, especially if the point mutations lie in exon 3 that codes for the highly conserved Tudor domain of the Smn protein. Although both our patients were carriers of intragenic SMN1 mutations in the coding region of the Tudor domain, they presented with a mild SMA phenotype despite a low SMN2 copy number. We discuss the possible determinant role of these novel missense mutations in the phenotypic outcome and compensatory mechanisms that may account for the genotype-phenotype discrepancy.

Elevated levels of IFNγ and LIGHT in the spinal cord of patients with sporadic amyotrophic lateral sclerosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a paralytic and fatal neurodegenerative disorder caused by the gradual loss of both upper and lower motoneurons. There is compelling evidence from ALS experimental models that neuroinflammation actively contributes to motoneuron damage. We recently proposed that interferon gamma (IFNγ), a potent proinflammatory cytokine, induces motoneuron death by eliciting the activation of the lymphotoxin beta receptor (LT-βR) through its ligand LIGHT. Here, we explore the pertinence of this non-cell-autonomous mechanism in human ALS.

METHODS

The levels and expression pattern of IFNγ, LIGHT, and LT-βR were investigated by Western blot and immunohistochemical analysis in spinal cord of patients with sporadic ALS.

RESULTS

  We observed significant increased levels of IFNγ in human ALS spinal cords compared to control cases. We found that large ventral horn neurons as well as glial cells were immunoreactive for IFNγ in sporadic ALS spinal cord. We further observed that LIGHT and LT-βR were expressed mainly by motoneurons in both ALS and control cases, and while LT-βR levels remained constant between ALS and control cases, LIGHT levels were increased in human ALS spinal cords.

CONCLUSION

These findings in sporadic ALS cases, which are consistent with the observation made in ALS experimental models, propose that the IFNγ-triggered LIGHT/LT-βR-mediated death pathway may contribute to human ALS pathogenesis.

What has changed with riluzole?

Riluzole, after two significant trials, was introduced as the first standard treatment of amyotrophic lateral sclerosis (ALS) in the early 95'. After 5 years what has changed in the field of ALS? In the field of basic science, riluzole as an active drug has largely contributed to stimulate the research of the possible role of glutamate in the genesis of ALS. However, the apparent simplicity of the relation between the drug and its mechanisms has to modulated in the light of the negativity of other trials (gabapentin) and the display of other mechanisms of the disease and of the compound. Possible relation with other putative mechanisms of ALS, as oxydative stress or growth factors, could be (and probably are) also involved. In the field of its activity, riluzole has an impact on the survival rate which has been largely debated. Comparison with historical databases are supporting the results of the two initial trials. Other information have been published supporting the probable activity of the drug on the muscle strength decline, a controversial matter. They strengthen the initial data and give additional reasons to use riluzole as a standard treatment of patients. In the field of the daily care, riluzole provided a real and unique hope for ALS sufferers. Even if its activity is not as complete as patients would have expected, it provides a hope for slowing down the rate of evolution and abolishes the myth of "no hope, no cure" which was the leitmotiv of patients care until recently. We have to better define the mode of administration with regard to the clinical status of the patients (respiratory disorders, fatigue, stiffness). In the field of care givers, riluzole was one major factor which provided the basis for national and international collaborations either for therapeutic trials or for standard of care. It made possible large collaborative programs in and among many countries. We do hope that this impulse will continue and be stimulated by additional results both in the field of basic science and clinical research.

Mutations in FUS cause FALS and SALS in French and French Canadian populations

BACKGROUND

The identification of mutations in the TARDBP and more recently the identification of mutations in the FUS gene as the cause of amyotrophic lateral sclerosis (ALS) is providing the field with new insight about the mechanisms involved in this severe neurodegenerative disease.

METHODS

To extend these recent genetic reports, we screened the entire gene in a cohort of 200 patients with ALS. An additional 285 patients with sporadic ALS were screened for variants in exon 15 for which mutations were previously reported.

RESULTS

In total, 3 different mutations were identified in 4 different patients, including 1 3-bp deletion in exon 3 of a patient with sporadic ALS and 2 missense mutations in exon 15 of 1 patient with familial ALS and 2 patients with sporadic ALS.

CONCLUSIONS

Our study identified sporadic patients with mutations in the FUS gene. The accumulation and description of different genes and mutations helps to develop a more comprehensive picture of the genetic events underlying amyotrophic lateral sclerosis.

Prognostic factors for survival in amyotrophic lateral sclerosis patients treated with riluzole

The objective of this study was to identify prognostic factors for survival in amyotrophic lateral sclerosis from a large prospective observational study performed in France. The study included a cohort of 2069 patients fulfilling broad entry criteria treated with riluzole. Over 100 demographic, biological, clinical and quality-of-life variables were monitored and assessed for their effect on survival. Patients were randomized post hoc into two groups: one group (two-thirds of the patients) to generate the prognostic models and one group (one-third of the patients) to validate the resulting models. Thirteen variables were found to affect survival independently and were used to construct a survival prediction score, RL401. These included age, disease duration, slow vital capacity, intensity of tiredness (visual analogue scale), number of body levels with spasticity, atrophy and/or fasciculations, cough, distal muscle strength, household income, depression and two biological parameters, plasma creatinine levels and neutrophil counts. A simplified score, RL401S, was constructed, designed to be easy to use and interpret. The predictive powers of the two scores were similar.

A large-scale international meta-analysis of paraoxonase gene polymorphisms in sporadic ALS

BACKGROUND

Six candidate gene studies report a genetic association of DNA variants within the paraoxonase locus with sporadic amyotrophic lateral sclerosis (ALS). However, several other large studies, including five genome-wide association studies, have not duplicated this finding.

METHODS

We conducted a meta-analysis of 10 published studies and one unpublished study of the paraoxonase locus, encompassing 4,037 ALS cases and 4,609 controls, including genome-wide association data from 2,018 ALS cases and 2,425 controls.

RESULTS

The combined fixed effects odds ratio (OR) for rs662 (PON1 Q192R) was 1.09 (95% confidence interval [CI], 1.02-1.16, p = 0.01); the genotypic OR for RR homozygotes at Q192R was 1.25 (95% CI, 1.07-1.45, p = 0.0004); the combined OR for rs854560 (PON1 L55M) was 0.97 (95% CI, 0.86-1.10, p = 0.62); the OR for rs10487132 (PON2) was 1.08 (95% CI, 0.92-1.27, p = 0.35). Although the rs662 polymorphism reached a nominal level of significance, no polymorphism was significant after multiple testing correction. In the subanalysis of samples with genome-wide data from which population outliers were removed, rs662 had an OR of 1.06 (95% CI, 0.97-1.16, p = 0.22).

CONCLUSIONS

In contrast to previous positive smaller studies, our genetic meta-analysis showed no significant association of amyotrophic lateral sclerosis (ALS) with the PON locus. This is the largest meta-analysis of a candidate gene in ALS to date and the first ALS meta-analysis to include data from whole genome association studies. The findings reinforce the need for much larger and more collaborative investigations of the genetic determinants of ALS.

Contribution of TARDBP mutations to sporadic amyotrophic lateral sclerosis

AIMS AND BACKGROUND

Mutations in the TARDBP gene, which encodes the TAR DNA binding protein (TDP-43), have been described in individuals with familial and sporadic amyotrophic lateral sclerosis (ALS). We screened the TARDBP gene in 285 French sporadic ALS patients to assess the frequency of TARDBP mutations in ALS.

RESULTS

Six individuals had potentially deleterious mutations of which three were novel including a Y374X truncating mutation and P363A and A382P missense mutations. This suggests that TARDBP mutations may predispose to ALS in approximately 2% of the individuals followed in this study.

CONCLUSION

Our findings, combined with those from other collections, brings the total number of mutations in unrelated ALS patients to 17, further suggesting that mutations in the TARDBP gene have an important role in the pathogenesis of ALS.

[Primary lateral sclerosis: the era of international diagnosis criteria]

Since Charcot's first description, primary lateral sclerosis (PLS) remains a rare clinical syndrome, a neuropathological phenotype of motor system degeneration. In turn, PLS has been described as belonging to the large spectrum of motoneuron diseases or to the diverse degenerative diseases of the nervous system. Clinically, it is characterized by progressive pyramidal involvement in patients who present insidiously progressive gait disorders and, on examination, have relatively symmetrical lower limb weakness, increased muscle tone, pathologic hyper-reflexia, and exaggerated extensor plantar responses. Pinprick, light touch, and temperature sensations are preserved. Viewed in another way, PLS mimicks progressive hereditary spastic paraparesis (HSP) and the "central" phenotype of amyotrophic lateral sclerosis (ALS). PLS is considered "idiopathic" and, depending on the presence or absence of similarly affected family members, the syndrome of idiopathic HSP and ALS are labeled "hereditary" or "apparently sporadic". The juvenile form of PLS and early age at onset in cases of HSP complicate our understanding of the relationship between these two disorders. Guidelines for diagnosis and genetic counseling have been published for HSP and ALS. Recently, since the first international workshop, guidelines for diagnosis of PLS propose a classification system, e.g. for heterogeneous HSP into "pure PLS", complicated or "plus PLS", symptomatic PLS and upper motor neuron-dominant ALS. However, when reviewing known cases of PLS drawn from the literature, rigorous retrospective application of these new PLS criteria raises an unanswered question: does pure PLS exist?

Dyslipidemia is a protective factor in amyotrophic lateral sclerosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is the most serious form of degenerative motor neuron disease in adults, characterized by upper and lower motor neuron degeneration, skeletal muscle atrophy, paralysis, and death. High prevalence of malnutrition and weight loss adversely affect quality of life. Moreover, two thirds of patients develop a hypermetabolism of unknown cause, leading to increased resting energy expenditure. Inasmuch as lipids are the major source of energy for muscles, we determined the status of lipids in a population of patients with ALS and investigated whether lipid contents may have an impact on disease progression and survival.

METHODS

Blood concentrations of triglycerides, cholesterol, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were measured in a cohort of 369 patients with ALS and compared to a control group of 286 healthy subjects. Postmortem histologic examination was performed on liver specimens from 59 other patients with ALS and 16 patients with Parkinson disease (PD).

RESULTS

The frequency of hyperlipidemia, as revealed by increased plasma levels of total cholesterol or LDL, was twofold higher in patients with ALS than in control subjects. As a result, steatosis of the liver was more pronounced in patients with ALS than in patients with PD. Correlation studies demonstrated that bearing an abnormally elevated LDL/HDL ratio significantly increased survival by more than 12 months.

CONCLUSIONS

Hyperlipidemia is a significant prognostic factor for survival of patients with amyotrophic lateral sclerosis. This finding highlights the importance of nutritional intervention strategies on disease progression and claims our attention when treating these patients with lipid-lowering drugs.

Phase II/III randomized trial of TCH346 in patients with ALS

BACKGROUND

TCH346 exerts antiapoptotic effects by binding to glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and blocking the apoptotic pathway in which GAPDH is involved. Apoptosis is considered to be a key pathogenic mechanism in neurodegenerative diseases including ALS.

METHODS

Patients were randomly assigned in a double-blind fashion to receive either placebo or one of four doses of TCH346 (1.0, 2.5, 7.5, or 15 mg/day) administered orally once daily for at least 24 weeks. The primary outcome measure was the rate of change in the revised ALS functional rating scale (ALSFRS-R). The trial design included a 16-week lead-in phase to determine each patient's rate of disease progression. The between treatment comparison was adjusted for the individual pretreatment rates of progression. The study was powered to detect a 25% reduction in the rate of decline of the ALSFRS-R as compared with placebo. Secondary outcome measures included survival, pulmonary function, and manual muscle testing (MMT).

RESULTS

Five hundred ninety-one patients were enrolled at 42 sites in Europe and North America. There were no differences in baseline variables. There were no significant differences between placebo and active treatment groups in the mean rate of decline of the ALSFRS-R or in the secondary outcome measures (survival, pulmonary function, and MMT).

CONCLUSION

The trial revealed no evidence of a beneficial effect of TCH346 on disease progression in patients with ALS.

The G526R glycyl-tRNA synthetase gene mutation in distal hereditary motor neuropathy type V

BACKGROUND

Distal hereditary motor neuropathy (dHMN) or distal spinal muscular atrophy (dSMA) is a heterogeneous group of disorders characterized almost exclusively by degeneration of motor nerve fibers, predominantly in the distal part of the limbs. One subtype, dHMN type V (dHMN-V), is transmitted by autosomal dominant inheritance and predominantly involves the hands. It is allelic with Charcot-Marie-Tooth disease 2D (CMT2D), in which a similar phenotype is associated with sensory signs. Missense mutations in the glycyl-tRNA synthetase (GARS) gene have been recently reported in families with either dHMN-V, CMT2D, or both.

METHODS

The authors searched for GARS mutations in eight dHMN-V families.

RESULTS

The authors found the G526R missense mutation in three families (16 patients) of Algerian Sephardic Jewish origin. All patients shared a common disease haplotype, suggestive of a founder effect. The clinical phenotype consists of a slowly progressive, purely motor distal neuropathy. It starts in the hands in most patients, but also in both distal upper and lower limbs or in distal lower limbs alone. The age at onset in symptomatic individuals was between the second to fourth decades, but four mutation carriers were still asymptomatic, two of whom were already age 49 years. Electrophysiology showed that the motor fibers of the median nerve were the most affected in upper limbs. Sensory nerve action potentials were normal.

CONCLUSIONS

The age at onset of patients with the G526R mutation in the GARS gene varied widely, but the clinical and electrophysiologic presentation was uniform and progressed slowly. Glycyl-tRNA synthetase mutations are a frequent cause of familial distal hereditary motor neuropathy type V but, because of the reduced penetrance of the disease, could also account for isolated cases.

[Ethical aspects for substitute decisions and their reversion in amyotrophic lateral sclerosis]

Related to its clinical characteristics, amyotrophic lateral sclerosis (ALS) is a paradigm of the ethical difficulties due to a chronic and relentless fatal disease. Its fatal evolution in relation with a respiratory failure, but mainly the choices imposed by the respiratory insufficiency at the end of live, makes that the medical team faces very difficult situations. These situation can be solved only case per case, with repeated discussion with the patients and its relatives. The appeal to the shared dossier becomes essential in this approach. It makes easier the communication, and the appropriation and sharing of information and knowledge that are necessary to anticipate the end of life decisions. ALS sparks off constantly renewed dilemmas.

Pentoxifylline in ALS: A double-blind, randomized, multicenter, placebo-controlled trial

OBJECTIVE

To assess the efficacy and safety of pentoxifylline, a US Food and Drug Administration-approved drug, in patients with ALS treated with riluzole.

METHODS

The authors conducted a double-blind, randomized, placebo-controlled, multicenter trial. Four hundred patients with probable or definite ALS and vital capacity less than 100% were randomly assigned to treatment with placebo or 1.2 g pentoxifylline daily. The primary outcome was death. Secondary outcomes were rates of deterioration of ALS Functional Rating Scale-Respiratory and muscle strength. The primary intention-to-treat analysis was the survival comparison of drug vs placebo, assessed before (log-rank test) and after adjustment (Cox model) for predefined prognostic factors.

RESULTS

At the end of the study, after 547 days of follow-up, 103 patients (51.7%) in the pentoxifylline group and 120 (59.7%) in the placebo group were alive (unadjusted risk 1.28, p = 0.107; adjusted risk 1.43, p = 0.02). In contrast, analysis of secondary outcome functional variables did not show the same negative effect of the drug. The most common adverse reactions were nausea, dysphagia, and flushing, all reversible after stopping the drug.

CONCLUSIONS

Pentoxifylline is not beneficial in ALS and should be avoided in patients treated with riluzole. The discrepancy between survival and measures of functional changes urges caution in equating these end points in phase III trials, and suggests that both survival and function should be used in phase III trials.

Physiopathologie de la Sclérose Latérale Amyotrophique : approches thérapeutiques

The finding in 1993 of a mutation of the copper zinc super oxyde dismutase (SOD1) provides a major breakthrough in the understanding of the etiopathogenic mechanism of amyotrophic lateral sclerosis. Various mechanisms are commonly implied in the motor neurons degeneration. Excitotoxicity and calcium metabolism abnormalities are one of the most frequently confirmed hypotheses. It allowed proposing riluzole which remains the only one drug proved to be active in the disease. The role of growth factors remains controversial and all therapeutic trials performed with these molecules remained negative. Oxidative stress abnormalities are demonstrated by number of studies but their direct therapeutic application remains to be demonstrated. Apoptosis and the role of mitochondria has been definitely confirmed and open a new therapeutic avenue for the next few years.

Mécanismes moléculaires de la sclérose latérale amyotrophique : apports récents de l’analyse de modèles animaux

Amyotrophic Lateral Sclerosis is a neurodegenerative condition defined by loss of both upper and lower motor neurons. The molecular mechanisms underlying this pathology are currently elucidated using transgenic mice lines expressing mutated alleles of the copper-zinc superoxide dismutase, an enzyme mutated in about 2 p. cent of ALS cases. These transgenic mice also provide a valuable animal model to set up new therapeutic tools.

The relationship between Bunina bodies, skein-like inclusions and neuronal loss in amyotrophic lateral sclerosis

Specific pathological hallmarks have been described in amyotrophic lateral sclerosis (ALS), which include motor neuronal loss, Bunina bodies (BBs) and skein like inclusions (SLIs). We investigated the relation between these three lesions in the cervical and lumbar anterior horns and the hypoglossal nuclei of 20 ALS patients and 9 controls using a quantitative light microscopy study. Immunohistochemistry with anti-cystatin C and anti-ubiquitin was used to detect the BBs and SLIs, respectively. A significant relation between the severity of neuronal loss and the proportion of SLI-containing neurons was found in the spinal cord, whereas no relation was found with BBs. We therefore propose that BBs and SLIs participate in two different steps of the cascade leading to neuronal loss.

[Nocturnal oxymetry in patients with amyotrophic lateral sclerosis: role in predicting survival]

Death is the most important end point along the course of amyotrophic lateral sclerosis (ALS). It is commonly attributed to a respiratory failure in relation with a restrictive respiratory disorder. However, in clinical practice, it is frequent to observe that death has not direct relation with the values of the respiratory function, at least measured with vital capacity. It is also frequent that relatives report sudden death during nocturnal sleep. All these features raised the question of the possible relation between death and nocturnal oxymetry in ALS patients. In a prospective study, we studied 69 ALS patients. We recorded demographic data, clinical parameters as manual muscle testing and functional scales, various parameters of oxymetry measured by pulse oxymetry recorded during night, slow vital capacity and survival time. There is a strong correlation between survival time measured by Kaplan Meier curves and log rank and the mean nocturnal saturation. We determined 93 mmHg as a threshold value. Below this threshold, mean survival time was 7.5+/-1.6 months and above it was equal to 18.5+/-1.5; relative risk was 3.31. These data confirm the importance of nocturnal oxymetry on survival in ALS patients both in clinical practice and in view of therapeutic trials.

A study of riluzole in the treatment of advanced stage or elderly patients with amyotrophic lateral sclerosis

Treatment with the neuroprotective drug riluzole has previously been shown to increase the probability of survival in patients with amyotrophic lateral sclerosis. This report describes a placebo-controlled, double-blind randomised clinical trial of riluzole carried out in ALS patients with advanced stage disease or aged over 75 years. The primary objective was to enable access to treatment to patients excluded from the pivotal trial which was run in parallel. Another goal was to assess the safety of riluzole in patients with advanced-stage disease. One hundred and sixty-eight patients were included, randomised to either riluzole 50 mg b. i. d. or to placebo, and treated for eighteen months. Riluzole was well-tolerated in this patient population, and the adverse events observed were similar in nature and frequency to those observed in previously published clinical trials in patients included in pivotal trials. The study could not include enough patients to reach adequate power to detect differences in survival between the two treatment groups, and no such difference was in fact observed. In conclusion, riluzole is well-tolerated in ALS patients with advanced stage disease.

APOE: a potential marker of disease progression in ALS

Although documented in AD, the role of APOE remains unclear in ALS. APOE phenotype and plasma levels were measured in 403 patients with ALS and were correlated with clinical parameters and survival time. No correlations were observed between the APOE phenotype and these variables. In contrast, APOE plasma levels were correlated with both rate of deterioration and survival time and appeared to be an important risk factor for decreased survival time with a relative risk of 0.647 (95% CI: 0.465 to 0.901; p = 0.01).

Long-term safety of riluzole in amyotrophic lateral sclerosis

OBJECTIVES

This international, open-label, multicentre extension of riluzole pivotal studies was designed to assess the long-term safety of riluzole in the treatment of amyotrophic lateral sclerosis (ALS).

METHOD

The studies were carried out at 31 different centres, 23 in Europe and eight in North America. 516 patients with diagnosed probable or definite ALS and who had participated previously in one of two international multicentre randomized double-blind placebo-controlled, parallel-group trials, were enrolled in the extensions. 58 of these patients had taken part in a randomized phase II trial (placebo or riluzole 100 mg/day) and 458 in a randomized, dose-ranging phase III trial (placebo or riluzole, 50, 100 or 200 mg/day). All participants in the open-label continuation received 100 mg/day of riluzole (50 mg b.i.d.)

RESULTS

At the end of the open-label study, the average exposure time of the patients to riluzole was 28.7 +/- 14.4 months, with a maximum exposure time of 81 months. Most of the adverse events recorded reflected the progression of ALS, in particular the deterioration of the respiratory status of the patients. No particular adverse event, or frequency of adverse event, appeared to be related to the dose level of the previous double-blind riluzole treatment. Nor were any adverse events associated with the switch-over from double-blind placebo to open-label riluzole.

CONCLUSIONS

This open-label extension study reinforces and extends the results of the preceding double-blind trials regarding the safety of riluzole and shows that the drug is well tolerated for long periods of up to almost 7 years.

[Tolerance of riluzole in a phase IIIb clinical trial]

Within the framework of an early drug access programme launched in 1995, a multicentre open study was initiated in France in order to assess, inter alia, the safety of riluzole (50 mg twice a day) in a total of 2069 patients from 28 centres. This programme, a phase IIIb study with direct individual benefit, had two main objectives: to enable patients to receive riluzole therapy pending regulatory approval and commercial availability and to provide further data on the safety of riluzole in a broader ALS population. The most frequent adverse events related to riluzole treatment were: asthenia, nausea and elevation of serum transaminase levels. These observations, similar to data derived from previous pivotal clinical trials, confirm that riluzole has a satisfactory tolerability profile.

Does primary lateral sclerosis exist? A study of 20 patients and a review of the literature

The question of whether primary lateral sclerosis (PLS) is a nosological entity distinct from amyotrophic lateral sclerosis (ALS) has been the subject of controversy since it was first described in the nineteenth century. PLS has been defined as a rare, non-hereditary disease characterized by progressive spinobulbar spasticity, related to the selective loss of precentral pyramidal neurones, with secondary pyramidal tract degeneration and preservation of anterior horn motor neurones. In the recent clinical literature, the frontier between ALS and neurodegenerative disease remains poorly defined. We studied 20 patients with a diagnosis of PLS. We carried out a variety of tests in order to determine the presence of a more diffuse neurodegenerative process. We also performed a longitudinal electrophysiological evaluation. Our clinical, electrophysiological and pathological investigations provide evidence that the disease has a heterogeneous clinical presentation and that degeneration is not restricted to the central motor system.

Case report of pallido-pyramidal disease with supplementary motor area involvement

An C-flumazenil positron emission tomography (PET) study in a patient with pallido-pyramidal disease revealed a marked decrease in benzodiazepine-receptor density in the precentral gyrus cortex and the mesial frontal cortex. We suggest that, in addition to dysfunction of basal ganglia-dependent systems, degeneration of the supplementary motor area could also be involved in the patient's bradykinesia.

[Neurodegenerative diseases of the spinal cord]

Numerous classifications have been applied to describe degenerative diseases of the spinal cord before the era of molecular analysis. The present challenge is to match in an appropriate manner old and new clinical classifications with the results of genetic analysis. This work is now well advanced for spinocerebellar degeneration but needs to be developed for hereditary spastic paraplegia, spinal muscular atrophies and amyotrophic lateral sclerosis. The widening of clinical spectrum observed in hereditary neurodegenerative diseases of the spinal cord raises the question of modulating factors (environmental or genetic). Clinicians in charge of patients with progressive spinal cord signs should bear in mind that the field of degenerative diseases is a moving one and that a degenerative aetiology has to be suspected more widely than in the past.

Primary lateral sclerosis: further clarification

Primary lateral sclerosis (PLS) has been defined as a rare. Non-hereditary disease characterized by progressive spinobulbar spasticity, related to the exclusive involvement of precentral pyramidal neurons, with secondary pyramidal tract degeneration and a preservation of anterior horn motor neurons, the latter allowing PLS to be distinguish from amyotrophic lateral sclerosis (ALS). However, a clear distinction between the two diseases remains a subject of debate. With this in mind, we assessed patients with meeting the previously published criteria for PLS in a prospective, longitudinal study. At regular intervals, we analyzed various clinical and electrophysiological parameters in nine patients with a diagnosis of PLS. We made a deltoid muscle biopsy and PET study.Our results provide evidence that degeneration in PLS is not restricted to the upper motor neurons but also affects the lower motor neurons. The distinction between ALS and PLS is related to the degree and stability of lower motor neuron involvement. In view of the similarities with ALS, we consider that PLS may represent a slowly progressive syndrome closely related to this disease.

Clinical trials: the past, a lesson for the future

Numerous drugs have been tested in amyotrophic lateral sclerosis with the expectation both that they will treat patients and improve our understanding of some of the basic mechanisms of the disease. Most of these trials were considered to be negative. Careful analysis of the trials does not allow us to clearly discard any of the tested drugs, or any of the suspected mechanisms. Expectations for the future are that: a) we need to be realistic about what to expect; b) we have to define clearly our end-points; c) we have to calculate the expected power before the trials, not after; and d) we have to improve our understanding of the pharmacology.

Intravenous immunoglobulin therapy in multifocal motor neuropathy: a double-blind, placebo-controlled study

We conducted a double-blind, placebo-controlled, study of 19 patients fulfilling eligibility criteria for multifocal motor neuropathy with persistent conduction block. They were enrolled and divided into two groups: those who had never been treated previously with intravenous immunoglobulins (IVIg) (Group 1: 10 patients) and those who presented recurrent symptoms after previously successful treatment with IVIg (Group 2: nine patients). They were randomized prospectively to receive either IVIg or placebo at a dose of 500 mg/kg/day for 5 consecutive days, once a month for 3 months. At month 4, patients found to be responders remained on the same treatment for the 3 following months, while non-responders were switched to the alternative study drug for the 3 following months. Clinical assessment was conducted with the MRC score in 28 muscles and a self-evaluation scale (five daily motor activities scored from 0 to 5). In Group 1, nine patients completed the study, of whom initially four received IVIg and five placebo; four patients responded to IVIg (two at months 4 and 7, and a further two at month 7 after switching treatment at month 4), two patients responded to placebo at months 4 and 7, and three patients did not respond to either treatment. In Group 2, nine patients completed the study. Five patients first received IVIg and all responded at months 4 and 7. Four patients first received placebo and none responded at month 4; all were then switched to IVIg and three responded at month 7. When the 18 patients were considered together, seven out of the nine patients who received IVIg first were responders at month 4, compared with two of the nine patients who received placebo first, a difference that was statistically significant (P = 0.03). On the other hand, there was no significant difference in MRC score but a significant difference in the self-evaluation score, at month 4, between IVIg patients and placebo patients. Electrophysiological studies did not show significant differences at month 4 in motor parameters between IVIg patients and placebo patients. IgM anti-GM1 titres did not change significantly in patients treated with IVIg compared with those who received placebo, between baseline, month 4 and month 7. However, of five patients who had significantly high anti-GM1 titres (>3200) at baseline, four responded to IVIg. This trial confirms that IVIg is a promising therapeutic option for multifocal motor neuropathy.

What has changed with riluzole?

Riluzole, after two significant trials, was introduced as the first standard treatment of amyotrophic lateral clerosis (ALS) in the early 95'. After 5 years what has changed in the field of ALS? In the field of basic science, riluzole as an active drug has largely contributed to stimulate the research of the possible role of glutamate in the genesis of ALS. However, the apparent simplicity of the relation between the drug and its mechanisms has to modulated in the light of the negativity of other trials (gabapentin) and the display of other mechanisms of the disease and of the compound. Possible relation with other putative mechanisms of ALS, as oxydative stress or growth factors, could be (and probably are) also involved. In the field of its activity, riluzole has an impact on the survival rate which has been largely debated. Comparison with historical databases are supporting the results of the two initial trials. Other information have been published supporting the probable activity of the drug on the muscle strength decline, a controversial matter. They strengthen the initial data and give additional reasons to use riluzole as a standard treatment of patients. In the field of the daily care, riluzole provided a real and unique hope for ALS sufferers. Even if its activity is not as complete as patients would have expected, it provides a hope for slowing down the rate of evolution and abolishes the myth of "no hope, no cure" which was the leitmotiv of patients care until recently. We have to better define the mode of administration with regard to the clinical status of the patients (respiratory disorders, fatigue, stiffness). In the field of care givers, riluzole was one major factor which provided the basis for national and international collaborations either for therapeutic trials or for standard of care. It made possible large collaborative programs in and among many countries. We do hope that this impulse will continue and be stimulated by additional results both in the field of basic science and clinical research.