Can we eliminate placebo in ALS clinical trials?

Inflammation, immunity, and amyotrophic lateral sclerosis: II. immune-modulating therapies

With the emerging popularity of immune-modulatory therapies to treat human diseases there is a need to step back from hypotheses aimed at assessing a condition in a single-system context and instead take into account the disease pathology as a whole. In complex diseases, such as amyotrophic lateral sclerosis (ALS), the use of these therapies to treat patients has been largely unsuccessful and likely premature given our lack of understanding of how the immune system influences disease progression and initiation. In addition, we still have an incomplete understanding of the role of these responses in our model systems and how this may translate clinically to human patients. In this review we discuss preclinical evidence and clinical trial results for a selection of recently conducted studies in ALS. We provide evidence-based reasoning for the failure of these trials and offer suggestions to improve the design of future investigations. Muscle Nerve 59:23-33, 2019.

Nutritional status evaluation in patients affected by bethlem myopathy and ullrich congenital muscular dystrophy

Collagen VI mutations lead to disabling myopathies like Bethlem myopathy (BM) and Ullrich congenital muscular dystrophy (UCMD). We have investigated the nutritional and metabolic status of one UCMD and seven BM patients (five female, three male, mean age 31 ± 9 years) in order to find a potential metabolic target for nutritional intervention. For this study, we used standard anthropometric tools, such as BMI evaluation and body circumference measurements. All results were compared to dual-energy X-ray absorptiometry (DXA), considered the “gold standard” method. Energy intake of each patient was evaluated through longitudinal methods (7-day food diary) while resting energy expenditure (REE) was predicted using specific equations and measured by indirect calorimetry. Clinical evaluation included general and nutritional blood and urine laboratory analyses and quantitative muscle strength measurement by hand-held dynamometry. BM and UCMD patients showed an altered body composition, characterized by low free fat mass (FFM) and high fat mass (FM), allowing us to classify them as sarcopenic, and all but one as sarcopenic-obese. Another main result was the negative correlation between REE/FFM ratio (basal energy expenditure per kilograms of fat-free mass) and the severity of the disease, as defined by the muscle megascore (correlation coefficient −0.955, P-value <0.001). We postulate that the increase of the REE/FFM ratio in relation to the severity of the disease may be due to an altered and pathophysiological loss of energetic efficiency at the expense of skeletal muscle. We show that a specific metabolic disequilibrium is related to the severity of the disease, which may represent a target for a nutritional intervention in these patients.

Body composition, muscle strength, and physical function of patients with Bethlem myopathy and Ullrich congenital muscular dystrophy

OBJECTIVE

To determine the contributions of body mass, adiposity, and muscularity to physical function and muscle strength in adult patients with Bethlem myopathy (BM) and Ullrich congenital muscular dystrophy (UCMD).

MATERIALS AND METHODS

Evaluation involved one UCMD and 7 BM patients. Body composition was determined by body mass index (BMI) and dual-energy-X-ray-absorptiometry (DXA), muscle strength by dynamometry, physical function by the distance walked in 6 minutes (6MWD), forced vital capacity (FVC) by a spirometer.

RESULTS

Six participants were of normal weight and 2 overweight based on BMI; all were sarcopenic based on appendicular fat free mass index (AFFMI); and 7 were sarcopenic obese based on AFFMI and % fat mass. Average muscle strength was reduced below 50% of normal. The 6MWD was in BM patients 30% less than normal. FVC was reduced in 4 of the BM patients. Muscle strength had a good correlation with the physical function variables. Correlation between muscle strength and BMI was poor; it was very high with AFFMI. AFFMI was the best single explicator of muscle strength and physical function.

CONCLUSION

Muscle mass determined by DXA explains most of the variability of the measures of muscle strength and physical function in patients with BM and UCMD.

Diaphragm pacing in amyotrophic lateral sclerosis: a literature review

Amyotrophic lateral sclerosis (ALS) remains a rapidly progressive fatal degenerative disease of motor neurons for which there are few interventions to slow disease progression or improve quality of life. A diaphragm pacing system was approved by the U.S. Food and Drug Administration in September 2011 for ALS under a Humanitarian Device Exemption. News of this approval has been met with a combination of excitement and uncertainty by members of the ALS community. We review the currently available data on the diaphragm pacing system and its use in ALS. Diaphragm pacing appears to be reasonably safe in carefully selected patients, but flaws in the reporting on it thus far preclude conclusions regarding efficacy. Further study is needed.

The epidemiology and treatment of ALS: focus on the heterogeneity of the disease and critical appraisal of therapeutic trials

Abstract Effective treatments for amyotrophic lateral sclerosis (ALS) have remained elusive. Only riluzole, a drug thought to affect glutamate metabolism, improves survival albeit to modest extent. Explanations for the negative results of therapeutic trials include a likely heterogeneity, both in disease susceptibility and pathogenic mechanisms, and faulty methodology of clinical trials. Further understanding of these factors will lead to improvements in patient stratification, and in the design of future clinical trials.

Neurotrophic growth factors for the treatment of amyotrophic lateral sclerosis: where do we stand?

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease that results in progressive loss of motoneurons, motor weakness and death within 3–5 years after disease onset. Therapeutic options remain limited despite substantial number of approaches that have been tested clinically. Many neurotrophic growth factors are known to promote the survival of neurons and foster regeneration in the central nervous system. Various neurotrophic factors have been investigated pre-clinically and clinically for the treatment of ALS. Although pre-clinical data appeared promising, no neurotrophic factors succeeded yet in a clinical phase III trial. In this review we discuss the rationale behind those factors, possible reasons for clinical failures, and argue for a renewal of hope in this powerful class of drugs for the treatment of ALS.

Prognostic factors in ALS: A critical review

We have performed a systematic review to summarize current knowledge concerning factors related to survival in ALS and to evaluate the implications of these data for clinical trials design. The median survival time from onset to death ranges from 20 to 48 months, but 10-20% of ALS patients have a survival longer than 10 years. Older age and bulbar onset are consistently reported to have a worse outcome. There are conflicting data on gender, diagnostic delay and El Escorial criteria. The rate of symptom progression was revealed to be an independent prognostic factor. Psychosocial factors, FTD, nutritional status, and respiratory function are also related to ALS outcome. The effect of enteral nutrition on survival is still unclear, while NIPPV has been found to improve survival. There are no well established biological markers of progression, although some are likely to emerge in the near future. These findings have relevant implications for the design of future trials. Randomization, besides the type of onset, should take into account age, respiratory status at entry, and a measure of disease progression pre-entry. Alternative trial designs can include the use of natural history controls, the so-called minimization method for treatment allocation, and the futility approach.

Electrical impedance myography to assess outcome in amyotrophic lateral sclerosis clinical trials

OBJECTIVE

Standard outcome measures used for amyotrophic lateral sclerosis (ALS) clinical trials, including the ALS functional rating scale-revised (ALSFRS-R), maximal voluntary isometric contraction testing (MVICT), and manual muscle testing (MMT), are limited in their ability to detect subtle disease progression. Electrical impedance myography (EIM) is a new non-invasive technique that provides quantitative data on muscle health by measuring localized tissue impedance. This study investigates whether EIM could provide a new outcome measure for use in ALS clinical trials work.

METHODS

Fifteen ALS patients underwent repeated EIM measurements of one or more muscles over a period of up to 18 months and the primary outcome variable, theta(z-max), measured. The theta(z-max) megascore was then calculated using the same approach as has been applied in the past for MVICT. This and the MMT data were then used to assess each measure's statistical power to detect a given effect on disease progression in a hypothetical planned clinical therapeutic trial.

RESULTS

theta(z-max) showed a mean decline of about 21% for the test period, averaged across all patients and all tested muscles. The theta(z-max) megascore had a power of 73% to detect a 10% treatment effect in our planned hypothetical trial, as compared to a 28% power for MMT. These results also compared favorably to historical data for ALSFRS-R and MVICT arm megascore from the trial of celecoxib in ALS, where both measures had only a 23% power to detect the same 10% treatment effect.

CONCLUSIONS

The theta(z-max) megascore may provide a powerful new outcome measure for ALS clinical trials.

SIGNIFICANCE

The application of EIM to future ALS trials may allow for smaller, faster studies with an improved ability to detect subtle progression of the disease and treatment effects.

Predictability of disease progression in amyotrophic lateral sclerosis

The aim of this study was to determine the predictors of disease progression in a group of 832 patients with the diagnosis of definite or probable amyotrophic lateral sclerosis (ALS). Disease progression was defined as the time to 20-point change in Appel ALS (AALS) score. The effects of individual prognostic factors on disease progression were assessed with the Kaplan-Meier life-table method. In addition, the prognostic value of each factor was estimated using both univariate and multivariate Cox proportional hazard analyses. The median time to a 20-point change in AALS score in our patient population was 9 months. Age, site of symptom onset, time between first symptom and first examination, total AALS score at first examination, and AALS preslope (rate of disease progression between first symptom and first examination) were significant and independent covariates of disease progression in our population. Identification of predictors of disease progression will facilitate better design of therapeutic trials, permitting the use of disease progression as a primary endpoint and improving baseline stratification of patient populations.

Molecular and cellular pathways of neurodegeneration in motor neurone disease

The process of neuronal degeneration in motor neurone disease is complex. Several genetic alterations may be involved in motor neurone injury in familial amyotrophic lateral sclerosis, less is known about the genetic and environmental factors involved in the commoner sporadic form of the disease. Most is known about the mechanisms of motor neurone degeneration in the subtype of disease caused by SOD1 mutations, but even here there appears to be a complex interplay between multiple pathogenic processes including oxidative stress, protein aggregation, mitochondrial dysfunction excitotoxicity, and impaired axonal transport. There is new evidence that non-neuronal cells in the vicinity of motor neurones may contribute to neuronal injury. The final demise of motor neurones is likely to involve a programmed cell death pathway resembling apoptosis.

Thrust joint manipulation clinical education opportunities for professional degree physical therapy students

STUDY DESIGN

Descriptive survey.

OBJECTIVE

Describe the availability of thrust joint manipulation clinical educational opportunities for physical therapy professional degree students.

BACKGROUND

In the United States, most of the faculty teaching manual therapy content in physical therapy programs believe that the best way for their students to develop thrust joint manipulation skills is to receive additional training during clinical education experiences. There are no data that describe the availability of such training opportunities.

METHODS AND MEASURES

Seventy-three physical therapy programs that include thrust joint manipulation in their curricula were divided into 5 geographic regions. Of these programs, 27% (total, n = 20) were randomly selected per region to participate. Program academic coordinators of clinical education (ACCEs) identified their clinical instructors working in outpatient orthopaedic settings. ACCEs and clinical instructors were surveyed regarding thrust joint manipulation clinical education opportunities for students.

RESULTS

Survey return rates were 100% for ACCEs and 67.4% for clinical instructors. Of ACCEs, 70% were unsure which sites employed clinical instructors trained in thrust joint manipulation and 85% did not consider whether thrust joint manipulation training was provided when scheduling the experience. The ACCEs who did consider availability cited lack of qualified instructors as the number-one barrier to finding sites that offered thrust joint manipulation. Of clinical instructors, 30% provide thrust joint manipulation training including lecture/theory, technique demonstration, practice on "normals," and direct patient care supervision. Clinical instructors who did not teach thrust joint manipulation cited reasons that included the belief that it is not an entry-level skill (57%), lack of qualified staff (53%), liability concerns (46%), and students not being academically prepared (41%).

CONCLUSIONS

Results suggest that the availability and scope of thrust joint manipulation clinical educational opportunities are limited, vary considerably, and are not considered when selecting clinical education sites for students. Potential obstacles to offering thrust joint manipulation training were identified, which suggested the need for resources, including clinical education curricula and philosophical guidelines for clinical instructors.