Follistatin 344 vs MK-2866 (Ostarine)
A side-by-side research comparison of Follistatin 344 and MK-2866 (Ostarine) across mechanism, dosing, half-life, benefits, side effects and research status.
Comparison table
| Attribute | Follistatin 344 | MK-2866 (Ostarine) |
|---|---|---|
| Full name | Follistatin 344 (FST-344) | Ostarine / Enobosarm (MK-2866) |
| Category | Muscle Growth | Muscle Growth |
| Status | Research compound | Investigational (not approved; banned in sport) |
| Mechanism | Binds myostatin and activin A with high affinity, preventing ActRIIB receptor activation. Removes the brake on muscle growth allowing uninhibited satellite cell proliferation. | Selectively binds androgen receptors in muscle and bone tissue, stimulating anabolic (muscle-building) signaling while having relatively less effect on the prostate and other androgen-sensitive tissues than testosterone. |
| Molecular weight | 36,000 Da | 389.33 Da |
| Half-life | 2-4 hours | ~24 hours |
| Bioavailability | Moderate (SubQ) | Oral |
| Typical dose | 100-200 mcg | Commonly cited 10-25 mg/day (research) |
| Frequency | Daily for 10-30 days | Once daily |
| Route | Subcutaneous | Oral |
Follistatin 344 reported benefits
- Significant muscle growth
- Myostatin inhibition
- Increased strength
- Activin neutralization
- Enhanced recovery
MK-2866 (Ostarine) reported benefits
- Lean muscle preservation/gain
- Bone density support (research)
- Less androgenic than steroids
- Studied for muscle wasting
Related comparisons
Research and educational reference only. Not medical advice.