Overview
Follistatin-344 is classified as a myostatin inhibitor peptide. Muscle hypertrophy, strength.
Blocks myostatin (the body's muscle growth limiter) and activin, allowing enhanced muscle development and regeneration beyond normal physiological limits.
Also known as: FS-344
Category
Myostatin Inhibitor
Half-Life
6h
Route
SubQ
FDA Status
Not Approved
How Does Follistatin-344 Work?
Blocks myostatin (the body's muscle growth limiter) and activin, allowing enhanced muscle development and regeneration beyond normal physiological limits.
At the molecular level, Follistatin-344 operates through pathways characteristic of the Myostatin Inhibitor class, interacting with target receptors and downstream signaling cascades to produce its observed effects.
Published Research
The following studies are indexed from PubMed and peer-reviewed journals:
[1]Follistatin gene therapy increases muscle mass and strength
Rodino-Klapac et al. (Mol. Ther.): AAV-delivered follistatin 344 increases muscle mass and fiber diameter across multiple animal species without adverse reproductive or endocrine effects.
Evidence: preclinical[2]Follistatin as myostatin antagonist therapeutic potential
Kalista et al.: Review of follistatin's role as primary endogenous myostatin antagonist and its therapeutic potential for muscular dystrophies and sarcopenia.
Evidence: preclinical[3]Follistatin gene transfer for Becker muscular dystrophy (Phase I)
Mendell et al. (Mol. Ther.): Phase I clinical trial of AAV1-follistatin gene transfer in Becker muscular dystrophy patients shows improved 6-minute walk test with no adverse effects.
Evidence: moderate[4]Follistatin in adipocyte differentiation and energy metabolism
Research demonstrating follistatin's broader metabolic role in adipocyte browning, energy expenditure, and metabolic health beyond muscle hypertrophy.
Evidence: preclinical[5]Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance.
A 2026 review found that while unapproved peptides like BPC-157 and TB-500 demonstrate favorable tissue repair in animal models, rigorous human safety data remain scarce. The researchers investigated the pharmacological mechanisms and regulatory status of these compounds in sports medicine.
Evidence: emerging[6]Sub-200 fs, 344 MHz mode-locked Tm-doped fiber laser.
In a 2020 study, researchers demonstrated a compact, self-starting mode-locked thulium-doped fiber laser achieving a fundamental repetition rate of 344 MHz and a pulse duration of 160 fs. The system generated pulses centered at 1975 nm with a maximum output power of 560 mW.
Evidence: emerging[7]Central serous chorioretinopathy associated with high-dose follistatin-344: a retrospective case series.
High-dose subcutaneous injections of follistatin-344 were associated with the development of central serous chorioretinopathy in eleven bodybuilding athletes, according to a 2020 retrospective case series. The study demonstrated that symptoms and subretinal fluid generally resolved after discontinuing the peptide.
Evidence: moderate[8]Detection of black market follistatin 344.
A 2019 study demonstrated that only nine of 17 tested black market follistatin 344 products actually contained the peptide. Researchers successfully developed an electrophoretic detection method to identify these His-tagged illicit peptides in serum and urine.
Evidence: preclinical[9]The transgenic expression of human follistatin-344 increases skeletal muscle mass in pigs.
A 2017 study demonstrated that transgenic expression of human follistatin-344 in pigs significantly increased skeletal muscle mass and reduced body fat. Researchers found this growth was driven by myofiber hypertrophy and altered signaling pathways, without causing cardiac or reproductive abnormalities.
Evidence: preclinicalSafety Profile
Research-only. Potent effects potential for unregulated growth. Limited human safety data. Phase I gene therapy trials show safety.
| Side Effect | Incidence | Severity |
|---|---|---|
| Limited human safety data | Investigational only | mild |
| Injection site reaction | ~5% of users | mild |
| Theoretical cancer promotion | Mechanism-based concern | rare |
Sourcing Follistatin-344 for Research
If you're looking to source Follistatin-344 for laboratory research, our vendor directory compares pricing, purity testing, and COA verification from independently vetted suppliers.
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Full Research Profile
Follistatin-344 — dosing, interactions, timelines & more
Comprehensive compound profile with sourcing information, stacking synergies, and outcome timelines.