CYTOKINETICS ANNOUNCES PUBLICATION OF RESULTS FROM PHASE II TRIAL OF TIRASEMTIV IN PATIENTS WITH MYASTHENIA GRAVIS
Data from Evidence of Effect Trial Provide Support for Novel Mechanism of Action in Neuromuscular Diseases
South San Francisco, CA - March 25, 2015
Cytokinetics, Incorporated (Nasdaq: CYTK) announced the publication of a manuscript relating to its fast skeletal muscle troponin activator tirasemtiv in the journal Neurotherapeutics. This publication summarizes results from a Phase IIa “Evidence of Effect” or hypothesis-generating clinical trial which evaluated tirasemtiv in patients with generalized myasthenia gravis (MG). Tirasemtiv is the lead drug candidate from Cytokinetics' skeletal muscle contractility program and is being developed as a potential treatment for amyotrophic lateral sclerosis (ALS).
“We are pleased to share additional clinical data relating to tirasemtiv in patients with generalized myasthenia gravis,” stated Andrew A. Wolff, MD, FACC, Cytokinetics’ Senior Vice President and Chief Medical Officer. “We believe that effects observed on the Quantitative Myasthenia Gravis score and on vital capacity following administration of a single dose of tirasemtiv support the evaluation of skeletal muscle activation in patients with neuromuscular disorders including ALS. We are preparing to initiate a Phase III clinical development program to evaluate the effects of tirasemtiv on measures of respiratory function and other measures of skeletal muscle performance in patients with ALS.”
The publication, titled “A Double-Blinded, Randomized, Placebo-Controlled Trial to Evaluate Efficacy, Safety, and Tolerability of Single Doses of Tirasemtiv in Patients with Acetylcholine Receptor-Binding Antibody-Positive Myasthenia Gravis,” appeared online in the March edition of the journal Neurotherapeutics. The primary objective of this early-stage clinical study was to evaluate the effects of single 250 mg and 500 mg doses of tirasemtiv versus placebo on measures of skeletal muscle function and fatigability in patients with generalized MG and persistent muscle weakness. The secondary objectives of the study were to evaluate and characterize the relationship, if any, between the doses and plasma concentrations of tirasemtiv and its pharmacodynamic effects, and to evaluate the safety and tolerability of tirasemtiv administered as single doses to patients with MG. The authors concluded that 6 hours after dosing, tirasemtiv produced dose-related improvements from baseline in the Quantitative MG (QMG) score (slope: –0.49 QMG point per 250 mg administered; p=0.02; lower scores indicate better function) and in percent predicted forced vital capacity (slope: 2.2 % increase per 250 mg administered; p=0.04). The QMG improved by >3 points in twice as many patients after 500 mg tirasemtiv than after placebo. Both doses of tirasemtiv were well tolerated; there were no premature terminations or serious adverse events. The results of this study suggest that tirasemtiv may improve muscle function in patients with MG and support further development of tirasemtiv in neuromuscular diseases.
