Is ACE-031 a peptide?

It is a recombinant fusion protein with a peptide receptor domain; it is grouped with muscle-growth biologics and is prohibited in sport.

Did ACE-031 cure muscular dystrophy?

No. Early trials showed some lean-mass gains but also significant safety signals

Can healthy people use it for muscle gain?

No approved or safe use exists for healthy individuals.

growth

ACE-031

ACE-031 is a soluble activin receptor type IIB-Fc fusion protein that inhibits myostatin and related ligands. It has been tested in randomized trials for muscular dystrophy but is not approved for any use.

Ian Gauntt, RN BSN1 min readHuman RCT

Aliases: ACVR2B-Fc, Regulon

Educational content only — this is not medical advice. Nothing here is a recommendation to buy, obtain, or use ACE-031. Talk to a licensed clinician before making health decisions.

What it is

ACE-031 is a recombinant fusion protein containing the extracellular domain of the activin receptor type IIB linked to an immunoglobulin Fc domain. By binding myostatin, activin A, and related transforming growth factor-beta ligands, it removes a brake on muscle growth. It was developed for Duchenne muscular dystrophy.

What the evidence shows

Phase 1 and 2 trials in Duchenne muscular dystrophy showed dose-dependent increases in lean mass and improvements in some muscle-function endpoints. However, development was paused due to safety signals, including nosebleeds, gum bleeding, and telangiectasias (small blood-vessel lesions). It remains investigational.

Risks & unknowns

Phase trials revealed bleeding events, skin vascular lesions (telangiectasias), and potential effects on the reproductive system due to broad ligand inhibition. Long-term safety, including effects on the heart, vessels, and cancer risk, is unknown.

Legal / regulatory status

ACE-031 is not FDA-approved. It is prohibited by WADA under S2. It is not legal to market for human use.

FAQ

Is ACE-031 a peptide?: It is a recombinant fusion protein with a peptide receptor domain; it is grouped with muscle-growth biologics and is prohibited in sport.
Did ACE-031 cure muscular dystrophy?: No. Early trials showed some lean-mass gains but also significant safety signals
Can healthy people use it for muscle gain?: No approved or safe use exists for healthy individuals.

ACE-031

What it is

What the evidence shows

Risks & unknowns

Legal / regulatory status

FAQ

References