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Follistatin
The burned-in captions and transcript carry the scientific claims and their limitations. The visuals are conceptual illustrations, not validated molecular models or experimental images. The video has no voice or audio. The full explanation is visible on screen; optional accessible captions are available in the player.
Read every result in its study context. A cell experiment, animal model, exploratory analysis and controlled human trial answer different questions.
Prepared 05 November 2026. Regulatory status is jurisdiction- and date-specific. No claim of specialist review or exhaustive evidence coverage.
Transcript
A network, not one switch
Muscle growth is regulated by many signals. Follistatin is a protein that can bind members of that signaling network, including myostatin and activins. [1]
Early human study | 6 participants
Researchers have explored this biology in muscle disease. One early human study delivered a follistatin gene to six people with Becker muscular dystrophy. [1]
Preliminary findings
Some participants improved on a walking test, but the study was small and lacked a randomized placebo comparison. It cannot establish a general muscle-building treatment. [1]
Different intervention | Sport restrictions
Gene delivery also differs fundamentally from a vial sold as follistatin. In regulated sport, myostatin-binding proteins such as follistatin are prohibited. Product claims need much more than a shared name. [1] [2]
Sources and context
These linked sources support the evidence distinctions in this short overview. This is not a systematic review, endorsement or treatment recommendation.
- Mendell et al.: Phase 1/2a follistatin gene therapy trial for Becker muscular dystrophy →Follistatin biology, six-person gene-transfer study, design and outcomes.
- WADA 2026 Prohibited List →Follistatin as a prohibited myostatin-binding protein.
