Is ACE-031 still being developed?

No. Clinical development of ACE-031 was halted in 2013 by Acceleron Pharma due to safety concerns identified in a Phase 2 trial in boys with Duchenne muscular dystrophy. Epistaxis and telangiectasias (vascular side effects) were attributed to broad inhibition of TGF-beta superfamily ligands beyond myostatin. The myostatin pathway continues to be pursued through more selective approaches including apitegromab, trevogrumab, and bimagrumab.

Can ACE-031 be obtained from research peptide suppliers?

While some research peptide vendors claim to sell ACE-031, there are significant concerns about product authenticity. ACE-031 is a complex 130 kDa fusion protein (ActRIIB-Fc) that requires sophisticated mammalian cell culture systems to manufacture correctly. Simple peptide synthesis cannot produce this molecule. Products claiming to be ACE-031 from non-pharmaceutical sources may not contain the actual protein.

Why was ACE-031 discontinued while other myostatin inhibitors continue?

ACE-031 acted as a broad decoy receptor, trapping not only myostatin but also activins, GDF-11, and BMPs including BMP-9 and BMP-10 that are critical for vascular homeostasis. This broad binding profile caused vascular side effects. Newer approaches like apitegromab (selective anti- promyostatin) and trevogrumab (selective anti-myostatin) target myostatin more specifically, avoiding the vascular complications.

ACE-031: Community Protocols & Reports

Aggregated community experiences, protocols, and stacking patterns

Anecdotal ReportsBased on 15 community reports

Community-Sourced Information

The protocols and reports on this page are gathered from online communities and forums. They represent anecdotal experiences, not clinical evidence. Individual results vary significantly. This information is not medical advice and should not replace consultation with a qualified healthcare provider. Always verify dosing and safety information with peer-reviewed research before making any decisions.

For peer-reviewed dosing protocols, see the clinical dosing guide.

Browse community protocols for all 130 peptides →

✓Reviewed byEditorial Team

📅Updated February 16, 2026

Unverified

📌TL;DR

•1 community protocols documented
•Evidence level: Anecdotal Reports
•Based on 15 community reports
•1 stacking patterns reported

Clinical vs. Community Protocol Differences

How community-reported protocols differ from clinical research protocols.

Aspect	Clinical Approach	Community Approach	Significance
Clinical Development Status	ACE-031 clinical development was halted in 2013 after a Phase 2 trial in boys with Duchenne muscular dystrophy showed safety concerns including epistaxis (nosebleeds) and telangiectasias (spider veins), likely related to broad inhibition of TGF-beta superfamily ligands including activins and BMP-9/10 involved in vascular homeostasis.	Despite discontinuation, ACE-031 remains discussed in bodybuilding and muscle-building communities interested in myostatin inhibition. Some community members discuss sourcing from research peptide suppliers, though product authenticity and purity are significant concerns for a complex fusion protein.	high ACE-031 is a large (~130 kDa) fusion protein that is extremely difficult to manufacture outside pharmaceutical facilities. Claims of ACE-031 availability from research peptide vendors should be treated with strong skepticism regarding authenticity.
Safety Profile	Clinical trials identified significant vascular safety signals including epistaxis, telangiectasias, and gingival bleeding, leading to trial termination and program discontinuation.	Community discussions about ACE-031 often underestimate the safety concerns that led to its discontinuation. The vascular side effects observed in clinical trials represent a class effect of broad ActRIIB inhibition, not a dosing issue.	high The safety concerns that halted ACE-031 development led to the pursuit of more selective myostatin inhibition approaches such as apitegromab and trevogrumab.

Compare these community approaches with published research findings.

Community Protocols

Historical Clinical Trial Protocol

Niche

Route: Subcutaneous injection
Dose: 0.5-3 mg/kg
Frequency: Every 2 weeks
Duration: 12 weeks (trial duration)

Based on published Phase 1/2 trial data; development halted in 2013 due to safety concerns

Stacking Patterns

Myostatin Inhibitor Research Interest

Niche

Community discussion of different myostatin inhibition approaches; theoretical comparison rather than established stacking protocol

ace-031 follistatin

Check stack compatibility and review potential side effects before combining peptides.

Unlock community dosing protocols and stacking combos

See the exact doses, routes, and schedules 15+ self-experimenters report. Free with email.

150+ peptide profiles · 30+ comparisons · 18 research tools

Already subscribed?

Sources

Reddit r/Peptides|ACE-031 and myostatin inhibitor discussions(accessed 2026-02-16)
Reddit r/steroids|Myostatin inhibitor compound discussion threads(accessed 2026-02-16)
PubMed|ACE-031 clinical trial publications and safety data(accessed 2026-02-16)

Community Evidence Overview#

This page presents aggregated community discussions and context for ACE-031 (ActRIIB-Fc). This is not clinical evidence and should not be used as medical guidance.

ACE-031 is a discontinued investigational compound. Its clinical development was halted in 2013 due to vascular safety concerns. Community discussion is primarily retrospective and educational, focused on understanding the myostatin inhibition landscape rather than active use protocols.

Why ACE-031 Was Discontinued#

The key safety issue was ACE-031's broad mechanism of action. As a soluble ActRIIB receptor, it trapped multiple TGF-beta superfamily ligands beyond myostatin, including BMP-9 and BMP-10 that are essential for vascular integrity. This led to epistaxis, telangiectasias, and gingival bleeding in clinical trial participants.

Product Authenticity Concerns#

Community members considering ACE-031 from research suppliers should be aware that this molecule is a large, complex fusion protein that cannot be produced through standard peptide synthesis. Legitimate production requires mammalian cell culture systems and sophisticated purification. Claims of ACE-031 availability from typical peptide vendors warrant significant skepticism.

The Myostatin Inhibition Landscape#

ACE-031's discontinuation contributed to the development of more selective approaches:

Apitegromab: Targets pro- and latent myostatin specifically
Trevogrumab: Selectively neutralizes mature myostatin
Bimagrumab: Blocks ActRII receptors with different selectivity profile

Subscribe to see vendor options

Free access to verified vendor scores, pricing, and suppliers.