Change in disease severity as measured by the ALS Functional Rating Scale-Revised (ALSFRS-R) total score using a Bayesian repeated measures model that accounts for loss to follow-up due to mortality. Each of 12 questions assessing distinct functional ability is scored from 4(normal) to 0 (no ability), with a maximum total score of 48 and a minimum total score of 0. Participants with higher scores have more physical function. Note that only participants who survived to their Week 24 visit contribute to the estimate.

Mortality is defined as death or death equivalent. A participant is determined to meet the criteria of death equivalent if permanent assisted ventilation (PAV) is used for more than 22 hours per day for more than seven days in a row. The rate of mortality was estimated from a Bayesian shared-parametric model that assumed exponentially distributed survival times.