Methodology Study of Novel Outcome Measures to Assess Progression of ALS

Longitudinal standardized mean change in electrophysiological measures as assessed by electrical impedance myography (EIM)

EIM is an electrophysiological technique in which current is applied to a muscle of interest and resultant voltage and impedance are measured. These measured parameters reflect the conductivity of underlying tissue and presumably the pathologic state of denervated muscle in an ALS participant

Time frame: Baseline to Month 6 and Baseline to Month 12

Longitudinal standardized mean change in electrophysiological measures as assessed by compound muscle action potential (CMAP)

CMAP is a standard electrophysiological measure generated by maximally stimulating a nerve such that all muscle fibers innervated by the respective nerve are depolarized. Reduction of CMAP amplitude reflects loss of motor axons and, therefore, is directly relevant to ALS.

Time frame: Baseline to Month 6 and Baseline to Month 12

Longitudinal standardized mean change in electrophysiological measures as assessed by motor unit number estimation (MUNE)

Optional, to be administered at each site's Investigator's discretion. MUNE is used to estimate the number of functioning motor units.

Time frame: Baseline to Month 6 and Baseline to Month 12

Longitudinal standardized mean change in electrophysiological measures as assessed by motor unit number index (MUNIX)

MUNIX estimates functioning motor units within a muscle. CMAP and surface electromyography potentials (surface interference patterns) are obtained at various levels of voluntary effort, and MUNIX is estimated using power and area of CMAP and surface interference patterns.

Time frame: Baseline to Month 6 and Baseline to Month 12

Longitudinal standardized mean change in muscle strength measures as assessed by hand-held dynamometry (HHD)

HHD tests isometric strength of multiple muscles using standard participant positioning. Approximately 10 muscle groups will be examined (per each side) in both upper and lower extremities.

Time frame: Baseline to Month 6 and Baseline to Month 12

Longitudinal standardized mean change in respiratory measures as assessed by slow vital capacity (SVC)

Vital capacity will be measured by means of an SVC test, administered in the upright position. Upright SVC will be determined by performing 3 to 5 measures, in accordance with criteria established by the American Thoracic Society and the European Respiratory Society.

Time frame: Baseline to Month 6 and Baseline to Month 12

Longitudinal standardized mean change in functional measures as assessed by Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R)

The ALSFRS-R has been demonstrated to predict survival. The ALSFRS-R measures 4 functional domains, including respiratory, bulbar function, gross motor skills, and fine motor skills. There are a total of 12 questions, each scored from 0 to 4 for a total possible score of 48 \[Cedarbaum 1999\], with higher scores representing better function.

Time frame: Baseline to Month 6 and Baseline to Month 12