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Updated: May 2, 2026

Assessment of Neuromuscular Function Using Percutaneous Electrical Nerve Stimulation
Published on: September 13, 2015
Tirasemtiv amplifies skeletal muscle response to nerve activation in humans
Richard Hansen1, Khalil G Saikali, Willis Chou
1Research and Early Development, Cytokinetics, Inc., 280 East Grand Avenue, South San Francisco, California, 94080-4808, USA.
Introduction:
In this study we tested the hypothesis that tirasemtiv, a selective fast skeletal muscle troponin activator that sensitizes the sarcomere to calcium, could amplify the response of muscle to neuromuscular input in humans.
Methods:
Healthy men received tirasemtiv and placebo in a randomized, double-blind, 4-period, crossover design. The deep fibular nerve was stimulated transcutaneously to activate the tibialis anterior muscle and produce dorsiflexion of the foot. The force-frequency relationship of tibialis anterior dorsiflexion was assessed after dosing.
Results:
Tirasemtiv increased force produced by the tibialis anterior in a dose-, concentration-, and frequency-dependent manner with the largest increases [up to 24.5% (SE 3.1), P < 0.0001] produced at subtetanic nerve stimulation frequencies (10 Hz).
Conclusions:
The data confirm that tirasemtiv amplifies the response of skeletal muscle to nerve input in humans. This outcome provides support for further studies of tirasemtiv as a potential therapy in conditions marked by diminished neuromuscular input.
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