What Is ACE-031? Benefits, Research & Safety
A myostatin/activin decoy receptor designed to promote muscle growth, researched for muscular dystrophy but development discontinued.
UK summary: Discontinued investigational compound. Acceleron Pharma stopped development of ACE-031 in 2013 after safety signals. Not a licensed UK medicine; not currently in active clinical development. Prohibited under WADA S1.2 / S4.
Quick Facts
Overview
ACE-031 — evidence and risk at a glance
Twenty standard modules scored against the Peptide Authority evidence grading methodology. Missing modules indicate the field has not yet been characterised editorially — treat absences as uncertainty rather than reassurance.
01Evidence snapshot
Discontinued investigational compound. Acceleron Pharma stopped development of ACE-031 in 2013 after safety signals. Not a licensed UK medicine; not currently in active clinical development. Prohibited under WADA S1.2 / S4.
02Human evidence grade
03Preclinical evidence grade
04Regulatory status
- UK: Not approved. Development discontinued.
- EU: Development discontinued. Not available.
- Notes: ACE-031 development was halted by Acceleron Pharma in 2013 due to vascular safety concerns. It never achieved regulatory approval. Related research continues with modified approaches.
05Approved medical uses
None in the UK or EU as a finished medicine. (Or: not yet documented; treat as absence rather than approval.)
06Unapproved / promotional claims
- Builds muscle like myostatin gene therapy.
- Restores muscle mass safely.
- Undetectable in drug tests.
07Common internet claims
- Marketed in bodybuilding stacks despite development halt.
- Sold by grey-market vendors as 'pharmaceutical-grade research peptide'.
08Claim vs evidence
| Claim | Evidence | Human evidence? | Regulatory concern | Safer wording |
|---|---|---|---|---|
| “Available from research suppliers for muscle building” | E | No | High | Development was halted on safety grounds. Any 'ACE-031' from grey-market suppliers has no provenance verification. |
09Safety uncertainty score
Effectively no human safety data; safety claims are extrapolations from animal work or anecdote.
10Known adverse signals
- Development halted in 2013 due to safety signals (nosebleeds, vascular issues).
- Theoretical reproductive disruption (myostatin / activin pathway).
- WADA S1.2 / S4 prohibited.
11Drug-interaction uncertainty
Interaction picture sparse; meaningful uncertainty when combined with other medicines.
12Anti-doping status
13UK legal position
Not approved. Development discontinued.
14EU legal position
Development discontinued. Not available.
15What this page cannot tell you
- Whether grey-market 'ACE-031' contains the originally developed compound or a different myostatin-pathway molecule.
- Long-term safety beyond the trials that ended in 2013.
16Last reviewed
17Citation quality score
18Research gaps
- No active clinical development; only historical Phase 1/2 data available.
19Safer alternatives / established care pathways
- Progressive resistance training with adequate protein.
- Neuromuscular-disease specialist referral for genuine muscle-wasting conditions.
20Doctor discussion prompts
Questions to ask a qualified clinician
These are starter questions you can adapt for a GP, specialist, pharmacist, or anti-doping advisor. The aim is to help you have a better-informed conversation — not to replace one.
- What licensed muscle-wasting treatments are appropriate?
Discovery & History
Mechanism of Action
Researched Benefits
Based on preclinical and clinical research findings:
- 1Significant increases in lean body mass (demonstrated in trials)
- 2Proof of concept for myostatin inhibition
- 3Potential for muscular dystrophy treatment (not realized)
- 4Increased muscle strength parallel to mass gains
- 5Informed development of related therapeutics
Claim vs Evidence
How popular claims about ACE-031 stack up against the current research, graded using our public evidence grading methodology.
| Claim | Evidence | Human evidence? | Regulatory concern | Safer wording |
|---|---|---|---|---|
| “Available from research suppliers for muscle building” | E | No | High | Development was halted on safety grounds. Any 'ACE-031' from grey-market suppliers has no provenance verification. |
Theoretical Dosing & Protocols
| Theoretical Dosage | Clinical trials used doses up to 3 mg/kg |
| Frequency | Every two weeks in trials |
| Duration | Development discontinued; no established protocols |
| Notes | ⚠️ ACE-031 development was discontinued due to safety concerns. It is not available for therapeutic use. This information is provided for educational purposes about the history of myostatin inhibition research. |
Administration Routes
Routes studied in research settings (educational only):
- Subcutaneous injection (clinical trials)
| Half-Life | Stability |
|---|---|
| Extended due to Fc fusion (approximately 10-14 days) | Standard protein handling requirements |
Safety Profile & Known Risks
Commonly Reported Side Effects
- Nosebleeds (epistaxis)
- Gum bleeding
- Telangiectasias (dilated blood vessels in skin)
- Injection site reactions
Rare Risks & Concerns
- Development discontinued due to vascular safety signals
- Long-term effects unknown
- Effects on other TGF-β pathways
Contraindications
- Development discontinued—not available for use
- History of bleeding disorders would have been concerning
UK & EU Regulatory Context
🇬🇧 United Kingdom
Not approved. Development discontinued.
🇪🇺 European Union
Development discontinued. Not available.
Clinical Studies Summary
Myostatin inhibitor ACE-031 treatment of ambulatory boys with Duchenne muscular dystrophy: Results of a randomized, placebo-controlled clinical trial.
ACE-031 use demonstrated trends for pharmacodynamic effects on lean mass, fat mass, BMD, and 6MWT. Non-muscle-related adverse events contributed to the decision to discontinue the study. Myostatin inhibition is a promising therapeutic approach for DMD. Muscle Nerve 55: 458-464, 2017.
A single ascending-dose study of muscle regulator ACE-031 in healthy volunteers.
Single-dose ACE-031 treatment was generally well-tolerated and resulted in increases in muscle mass in healthy postmenopausal women.
ACE-031, a soluble activin type IIB receptor, increases muscle mass and strength in the common marmoset (Callithrix jacchus).
The company is no longer active. This does not alter our adherence to PLOS ONE policies on sharing data and materials.
Gel Electrophoretic Detection of Black Market ACE-031.
In rat serum, BM ACE-031 was detectable up to 48 h post administration. However, due to the relatively high dose applied (10 mg/kg body weight) and possible differences in metabolism, the detection window may be different in humans.
The relationship between myodural bridges, hyperplasia of the suboccipital musculature, and intracranial pressure.
In contrast, surgically severing the MDB connections resulted in a significant decrease in intracranial pressure. Thus, these results indicated that muscular activation of the MDB may affect CSF circulation, suggesting a potential functional role of the MDB, and providing a new research perspective on CSF dynamics.
Emerging drugs affecting skeletal muscle function and mitochondrial biogenesis - Potential implications for sports drug testing programs.
Focusing on skeletal muscle and mitochondrial biogenesis, numerous substances exhibiting agonistic or antagonistic actions on different cellular 'control centers' resulting in increased skeletal muscle mass, enhanced performance (as determined with laboratory animal models), and/or elevated amounts of mitochondria have been described. Substances of interest include agonists for REV-ERBα (e.g.
Registered Trials & Regulatory Status
2 of 2 completed trials have never posted results. Unreported trials are not neutral: results that go unpublished are more often negative ones.
Extension Study of ACE-031 in Subjects With Duchenne Muscular Dystrophy
Status: Terminated · 11 participants · Acceleron Pharma, Inc., a wholly-owned subsidiary of Merck & Co., Inc., Rahway, NJ USA
Conditions: Duchenne Muscular Dystrophy
Study of ACE-031 in Subjects With Duchenne Muscular Dystrophy
Status: Terminated · 24 participants · Acceleron Pharma, Inc., a wholly-owned subsidiary of Merck & Co., Inc., Rahway, NJ USA
Conditions: Duchenne Muscular Dystrophy
A Safety, Tolerability, Pharmacokinetic and Pharmacodynamic Study of ACE-031 in Healthy Postmenopausal Women
Status: Completed · 70 participants · Acceleron Pharma, Inc., a wholly-owned subsidiary of Merck & Co., Inc., Rahway, NJ USA
Conditions: Muscular Atrophy
A Safety, Tolerability, Pharmacokinetic and Pharmacodynamic Study of ACE-031 (ActRIIB-IgG1)in Healthy Postmenopausal Volunteers
Status: Completed · 48 participants · Acceleron Pharma, Inc., a wholly-owned subsidiary of Merck & Co., Inc., Rahway, NJ USA
Conditions: Muscle Loss
Adverse event reports (FDA FAERS)
Not applicable: no licensed product contains this peptide, so it is not reported through FAERS. This is an absence of surveillance, not evidence of safety.
Source: ClinicalTrials.gov and openFDA. Updated automatically.
Looking for ACE-031?
Source research-grade ACE-031 from a trusted UK supplier — third-party tested with certificate of analysis.
View at SupplierFrequently Asked Questions
Questions to ask a qualified clinician about ACE-031
These are starter questions you can adapt for a GP, specialist, pharmacist, or anti-doping advisor. The aim is to help you have a better-informed conversation — not to replace one.
- What licensed muscle-wasting treatments are appropriate?
UK regulatory & safety context
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