Compare peptides
Put two entries side by side — evidence, mechanism, risks, and community claims.
ACE-031
Limited
Research chemical
Summary
Soluble activin type IIB receptor fusion protein designed to trap myostatin/activin ligands and increase muscle mass; clinical development halted after safety signals.
Categories
Performance
Mechanism
Decoy ActRIIB extracellular domain fused to Fc binds GDF-8/activins, reducing SMAD2/3 inhibitory signaling on muscle growth.
Half-life
Days (Fc fusion PK)
Routes
Subcutaneous injection
Legal / access
Development discontinued clinically. Research material only; significant safety concerns.
Key risks
- Epistaxis and bleeding events in trials
- Vascular effects
- Unknown long-term safety
Common claims
- Rapid muscle gain narratives
- Myostatin blockade
- Recomp stacks
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