Outcome measures in amyotrophic lateral sclerosis clinical trials.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with an average survival of 3-5 years. While therapies for ALS remain limited, basic and translational ALS research has been host to numerous influential discoveries in recent years. These discoveries have led to a large pipeline of potential therapies that await testing in clinical trials. Until recently, ALS clinical trials have relied on a limited cadre of 'traditional' outcome measures, including survival and measures of function. These measures have proven useful, although imperfect, in Phase III ALS trials. However, their utility in early-phase ALS trials is limited. For these early trials, outcome measures focused on target engagement or biological pathway analysis might improve trial outcomes and better support the drug development process.