Checked 2026-11-10. Independent clinical review has not been completed. WADAFUK is independent of WADA and does not provide medical advice or an individual anti-doping determination.
Prohibited at all times
2026: prohibited at all times (S0). [1]
2026 List, S0, printed page 4 · 2026 rules apply from 1 January 2026. Any 2027 material below concerns future rules from 1 January 2027; it is not current clearance.
Identity and mechanism
Tirasemtiv, formerly CK-2017357, is a fast skeletal-muscle troponin activator that increases sensitivity to calcium. It is a different molecule from reldesemtiv, so findings should not be combined as if they described one drug. [2]
Human studies
The early healthy-volunteer programme included a 57-man safety study and a separate 12-man crossover experiment measuring electrically evoked muscle force. A stronger laboratory force response is not evidence of better competition performance. Company funding and author financial interests were disclosed. [2]
In VITALITY-ALS, 744 participants entered an initial tolerability period and 565 proceeded to randomization. Tirasemtiv did not significantly improve the primary 24-week slow-vital-capacity outcome or reported secondary outcomes. Treatment discontinuation was more frequent than with placebo, and dizziness, fatigue, nausea, weight loss and insomnia were reported more often. [3]
- The phase 3 findings were checked from the author-institution abstract, not the full article. The pre-randomization tolerability phase also selected the randomized population.
Interpretation
The available phase 3 evidence does not support presenting tirasemtiv as an effective ALS therapy. Acute healthy-volunteer physiology cannot establish chronic safety, injury recovery or athletic benefit. [3] [2]
What remains uncertain
- Full phase 3 methods, detailed adverse-event tables and disclosures were not independently accessible.
- No consumer-product or food exposure was verified.
Check the sources.
These are concise editorial paraphrases of selected sources, not a systematic review or a reproduction of source tables. Access depth is shown for each reference; an abstract-only check cannot resolve details found only in a full paper.
- WADA 2026 Prohibited List ↗Accessed 2026-11-10 · official_full_text_relevant_sections
Effective date; S0 printed page 4; S2 printed pages 7–8
- Hansen et al. 2014: tirasemtiv in healthy volunteers ↗Accessed 2026-11-10 · full_text_relevant_sections
Muscle & Nerve; DOI 10.1002/mus.24239; methods, results and disclosures
- VITALITY-ALS: tirasemtiv phase 3 trial, 2019 ↗Accessed 2026-11-10 · abstract_only
Duke institutional abstract; DOI 10.1080/21678421.2019.1612922
Check the current official WADA List and the relevant anti-doping authority for your sport, product, route and circumstances. Do not stop or change necessary treatment based on this page. Ask a qualified clinician about health decisions. Missing evidence does not establish safety.