Cytokinetics Inc. said the phase 3 study of tirasemtiv in amyotrophic lateral sclerosis, or ALS, failed to meet its main goal.
Results from the trial showed tirasemtiv did not exhibit a change from the baseline in slow vital capacity, a test to determine lung function, in patients with ALS when evaluated at 24 weeks following randomization.
The study also failed to achieve its secondary goal of a change from the baseline in slow vital capacity at 48 weeks.
Side effects were similar between patients who received tirasemtiv or placebo but more patients discontinued double-blind treatment on tirasemtiv than on placebo primarily due to non-serious side effects related to tolerability.
Cytokinetics said it is "deeply disappointed" by the study's results and has decided to suspend tirasemtiv's development.
The company said it believes its fast skeletal muscle activator, CK-2127107, will be better tolerated and potentially more effective than tirasemtiv in patients with ALS and look forward to phase 2 trial results in 2018.
ALS is a progressive neurodegenerative disease that affects about 30,000 people in the U.S. and a comparable number of patients in Europe. There are few treatment options for ALS patients.