Cytokinetics Announced Additional Results Relating to Tirasemtiv from Pre-Specificed Subgroup Analyses of BENEFIT-ALS

Effects of Tirasemtiv on Slow Vital Capacity During 12 Weeks of Double-Blind Treatment Were Observed Consistently Across Patient Subgroups

SOUTH SAN FRANCISCO, CA, July 10, 2014 - Cytokinetics, Incorporated (CYTK) announced that additional results from BENEFIT-ALS (Blinded Evaluation of Neuromuscular Effects and Functional Improvement with Tirasemtiv in ALS) were presented today during a poster presentation at the 13th International Congress on Neuromuscular Diseases in Nice, France. The results from pre-specified subgroup analyses of BENEFIT-ALS were presented by Andrew A. Wolff, M.D., F.A.C.C., Senior Vice President, Clinical Research and Development, and Chief Medical Officer of Cytokinetics. These results indicate that the reduced decline in Slow Vital Capacity (SVC) on tirasemtiv versus placebo in BENEFIT-ALS were observed consistently across all subgroups of patients with amyotrophic lateral sclerosis (ALS).

The effects of tirasemtiv versus placebo on the changes from baseline to the average score after 8 and 12 weeks of treatment for the primary and secondary endpoints were evaluated in pre-specified analyses of subgroups based on age, sex, geography, riluzole use, onset of disease, weight, body-mass index (BMI) and baseline respiratory function. Based on these results, the authors concluded that tirasemtiv reduced the decline in SVC versus placebo by a similar magnitude regardless of age (>65 versus riluzole use, site of ALS onset (bulbar versus limb), baseline pulmonary function, baseline weight, and baseline BMI. The reduced decline in SVC versus placebo was statistically significant within each subgroup examined except patients enrolled in Europe, those with bulbar onset, and those with a percent predicted SVC less the median at baseline. The authors concluded that tirasemtiv may have both immediate and longer term pharmacologic effects, especially on SVC, and that the potentially beneficial effects of tirasemtiv on measures of respiratory function and other assessments of skeletal muscle performance observed in BENEFIT-ALS merit further investigation.

"The consistent effects of tirasemtiv across pre-specified subgroups on the clinically meaningful measure of SVC corroborate our prior observations across the total population studied in BENEFIT-ALS," stated Dr. Wolff. "We believe that tirasemtiv is the first drug candidate to reduce the decline in SVC in ALS patients so consistently, regardless of age, sex, geographic region, riluzole use, site of disease onset, baseline pulmonary function and baseline weight and BMI. We are encouraged by these results as we continue to analyze data from BENEFIT-ALS to inform the potential further development of tirasemtiv in patients with ALS."