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ACE-031 (Ramatercept)

Aliases: Ramatercept · ActRIIB-Fc

Last verified: 2026-09-23

DiscontinuedLimited evidencePeptidesLow interest

The short version

A soluble fusion protein (ActRIIB receptor + IgG Fc) — a decoy that traps myostatin and related ligands. In Phase II for Duchenne muscular dystrophy it produced significant lean-mass gains. Key fact: Human data are limited: small trials or case-series reports exist, without large randomized studies. Acceleron/Shire Phase I/II; discontinued. Status: discontinued. Not approved; WADA-banned.

Identity & type

Molecular type
peptide
Origin
A soluble fusion protein (ActRIIB receptor + IgG Fc) — a decoy that traps myostatin and related ligands.

Mechanism of action

Binds TGF-β-family ligands (myostatin, activin, GDF11) before they activate ActRIIB → blocks muscle-growth-limiting signals.

not confirmed in humans

Dosing & routes

Official / clinical context

Development was abandoned; no active regulatory document exists. There are no official indications.

Regulator-approved labeling and published study designs — never a recommendation.

Community-reported practice

In trials: 1–3 mg/kg SC every 2–4 weeks. Experiences are rare and old (gray market pre-2013): rapid muscle growth, but also nose/gum bleeding and mild telangiectasia — the very reasons development was halted.

Unverified self-reports. Not medical advice. Not endorsement.

Expected effects (community)

Experiences are rare and old (gray market pre-2013): rapid muscle growth, but also nose/gum bleeding and mild telangiectasia — the very reasons development was halted.

Protocol — official vs community

Official / label

No approved protocol exists — development was discontinued. In the Acceleron/Shire Phase I/II program, doses of 1–3 mg/kg SC every 2–4 weeks were studied in DMD patients.

Duration: Trial-defined; the DMD program was halted in 2013 over safety signals (nosebleeds, telangiectasias, hypoglycemia).

The soluble-receptor concept survived in related molecules — luspatercept uses the same ActRIIB-ligand-trap logic and is approved for anemias — which is why the approach is credible even though this specific drug is not.

Community (anecdotal)

Gray-market vials appear sporadically at doses far below the mg/kg trial range, reflecting the drug's cost and scarcity rather than a considered protocol.

Cycle:
No standardized pattern.
Break:

The only real dosing data is the discontinued trial above. Anything sold today as 'ACE-031' is unverifiable, and the safety signals that killed the program apply to the mechanism, not just the formulation.

Human evidence

Human data are limited: small trials or case-series reports exist, without large randomized studies. Acceleron/Shire Phase I/II; discontinued.

Preclinical evidence

Acceleron/Shire Phase I/II; discontinued. Related molecules (e.g., Luspatercept, same concept) later approved for anemias.

Known risks

  • Nosebleeds, telangiectasias, hypoglycemia — DMD development halted in 2013 over safety signals.characterized
  • zbog sigurnosnih signala.characterized
  • Unregulated injectable supply — sterility, purity and accurate dose not assuredtheoretical

Teal: characterized in clinical/labeling contexts. Amber: theoretical or reported outside controlled settings.

Unknowns & evidence gaps

  • Long-term human safety
  • Optimal dose and pharmacokinetics

Frequently asked questions

References

Systematic references are being expanded; verify sources directly before any decision.