WhatPeptide

ACE-031

A recombinant fusion protein of the ActRIIB extracellular domain and human IgG1 Fc, developed by Acceleron Pharma. Acts as a circulating decoy receptor trapping myostatin, activin, and BMP9/10. Phase 2 DMD trial terminated in 2011 due to vascular safety signals (epistaxis, telangiectasias) from BMP9/10 cross-inhibition.

Moderate evidence Investigational Myostatin Inhibitor

Written by WhatPeptide Editorial Team · Last updated 2026-03-18

Currently in clinical trials — not yet approved for any indication.

Half-life

10-15 days (Phase 1 PK data; linear dose-proportional; Attie et al., PMID 23169607)

Dosage range

Phase 1: 0.02-3 mg/kg SC single dose; Phase 2 (DMD): 0.5-1.0 mg/kg SC every 2-4 weeks (Attie et al., PMID 23169607)

Administration

Subcutaneous injection

Research level

Moderate

How ACE-031 works

Sequesters myostatin (GDF-8), activin A, GDF-11, and BMP9/BMP10 in circulation, preventing their binding to membrane ActRIIB and blocking downstream ALK4/ALK5 → Smad2/3 signaling. The broad ligand-trapping mechanism also captured BMP9/10 essential for vascular endothelial integrity, explaining the safety signals.

Also known as: Ramatercept, RAP-031, ActRIIB-Fc, ActRIIB-IgG1, Soluble ACVR2B

Research relevance

Muscle Growth
Strong research relevance 80
Recovery & Healing
Some relevance 35
Injury Rehab
Some relevance 25
Fat Loss
Some relevance 20

Side effects & safety

Epistaxis (dose-dependent, from BMP9/10 cross-inhibition) Telangiectasias (dilated blood vessels) Gum/mucosal bleeding Injection-site erythema FSH suppression (~43% decrease at 3 mg/kg)

Contraindications

Bleeding disorders
Hereditary hemorrhagic telangiectasia
Concurrent anticoagulant therapy
Pregnancy

Consult a healthcare provider before use if any of these apply to you.

FAQ

What is ACE-031? +
A recombinant fusion protein of the ActRIIB extracellular domain and human IgG1 Fc, developed by Acceleron Pharma. Acts as a circulating decoy receptor trapping myostatin, activin, and BMP9/10. Phase 2 DMD trial terminated in 2011 due to vascular safety signals (epistaxis, telangiectasias) from BMP9/10 cross-inhibition. Its mechanism of action is supported by moderate clinical and preclinical evidence.
What is ACE-031 researched for? +
ACE-031 has the strongest research relevance for Muscle Growth, Recovery & Healing, Injury Rehab. Evidence is supported by moderate clinical and preclinical evidence.
What are the side effects of ACE-031? +
Reported side effects include Epistaxis (dose-dependent, from BMP9/10 cross-inhibition), Telangiectasias (dilated blood vessels), Gum/mucosal bleeding, Injection-site erythema, FSH suppression (~43% decrease at 3 mg/kg). Key contraindications: Bleeding disorders; Hereditary hemorrhagic telangiectasia; Concurrent anticoagulant therapy; Pregnancy.
Is ACE-031 FDA approved? +
ACE-031 is currently in clinical trials and is not yet approved by the FDA.
How is ACE-031 administered? +
ACE-031 is typically administered via subcutaneous route. Researched dosage range: Phase 1: 0.02-3 mg/kg SC single dose; Phase 2 (DMD): 0.5-1.0 mg/kg SC every 2-4 weeks (Attie et al., PMID 23169607). Half-life: 10-15 days (Phase 1 PK data; linear dose-proportional; Attie et al., PMID 23169607).

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