Side-by-side · Research reference

ACE-031vsLivagen

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

APhase 2HUMAN-REVIEWED10/44 cited

BAnimal-StrongHUMAN-REVIEWED20/32 cited

ACE-031

ActRIIB-Fc Fusion · Phase 2 Halted

Phase 2Highest trial stage

2011Development halted

~58.4 kDaMolecular weightReichel 2025

SQ · Weekly dosing investigated

Livagen

Khavinson Bioregulator · Hepatoprotective Tetrapeptide

50%Dipeptidase inhibitionTimofeeva 2005

Oral / SQRoutes tested

LiverTarget tissueKhavinson 2001

Oral or SQ · Tissue-specific to liver

01Mechanism of Action

Parameter

ACE-031

Livagen

Primary target

Myostatin, GDF11, activin A — TGF-β superfamily ligands

Hepatocyte protein synthesis machineryBrodskiĭ 2001

Pathway

Soluble decoy receptor binds circulating myostatin/TGF-β ligands → prevents ActRIIB activation → SMAD2/3 pathway inhibition

Tissue-specific bioregulator → Hepatocyte stimulation → Protein synthesis normalizationBrodskiĭ 2001 Khavinson 2001

Downstream effect

Disinhibition of myogenic signaling, increased skeletal muscle mass and strength

Age-dependent enzyme normalization, hepatoprotection in fibrosis/hepatitis models, elevated protein synthesis in senescent hepatocytes

Feedback intact?

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Origin

Recombinant fusion protein: human ActRIIB extracellular domain + IgG1-Fc fragmentReichel 2025

Directed chemical synthesis from amino acid analysis of liver polypeptide preparations (Ventvil)

Antibody development

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02Dosage Protocols

Parameter

ACE-031

Livagen

Clinical dosing

Weekly or biweekly SQ injections (exact doses undisclosed pre-halt)

Phase 2 DMD trial protocol not fully published.

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Black market products

Variable purity; 12/14 tested products contained target protein plus contaminantsReichel 2025

SDS-PAGE revealed multiple protein bands; quality control absent.Reichel 2025

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Evidence basis

Phase 2 trial discontinued — incomplete dataset

Animal models (rats, 1–24 months age); in vitro hepatocyte cultureTimofeeva 2005 Brodskiĭ 2001 Khavinson 2002

Half-life

Days to weeks (Fc-fusion typical kinetics)

IgG1-Fc domain confers extended circulation time.

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Duration investigated

12–24 weeks (trial cut short)

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Animal dose (oral)

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Not specified in abstracts; 2-week administration protocolTimofeeva 2005

Per os administration in rats.

Duration (experimental)

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2 weeks (enzyme study); up to 24 months (cell culture)Timofeeva 2005 Brodskiĭ 2001

Route

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Oral or subcutaneous

Resists peptidase hydrolysis, enabling oral bioavailability.Timofeeva 2005

Human data

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None in provided literature

04Side Effects & Safety

Parameter

ACE-031

Livagen

Epistaxis (nosebleeds)

Significant incidence in Phase 2 DMD trial — primary safety signal

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Telangiectasia

Dilated capillaries / spider veins observed

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Vascular abnormalities

Mechanism: ActRIIB/ALK1 pathway disruption affects vascular homeostasis

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Injection site reactions

Local erythema, induration (biologics class effect)

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Antibody development

Potential for anti-drug antibodies (Fc-fusion proteins); incidence not reported

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Black market contaminants

12/14 tested products contained multiple unidentified proteins alongside ACE-031Reichel 2025

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Reported adverse effects

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None documented in animal studies

Human safety data

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No human trials in provided literature

Peptide hydrolysis

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Weakly hydrolyzed; minimal breakdown by intestinal enzymesTimofeeva 2005

Absolute Contraindications

ACE-031

·History of vascular disorders (epistaxis, telangiectasia, HHT)
·Pregnancy (TGF-β pathway critical for fetal development)
·Active malignancy (myostatin inhibition may affect tumour growth)
·Use of non-pharmaceutical grade ACE-031 (contamination risk)Reichel 2025

Livagen

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Relative Contraindications

ACE-031

·Coagulation disorders or anticoagulant use (epistaxis risk)
·Hereditary hemorrhagic telangiectasia (HHT) family history
·Cardiovascular disease (vascular remodeling effects unknown)

Livagen

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05Administration Protocol

Parameter

ACE-031

Livagen

1. Pharmaceutical status

ACE-031 is not FDA-approved or commercially available. Phase 2 development was discontinued in 2011 due to safety concerns. Any ACE-031 on the black market is unregulated research chemical.

Oral administration supported by peptidase resistance. Subcutaneous route used in organotypic culture experiments.Timofeeva 2005 Khavinson 2001

2. Black market quality

12 of 14 tested black market ACE-031 products contained the target protein but also carried multiple unidentified protein contaminants detectable by SDS-PAGE. Two products contained no ACVR2B-immunoreactive material.Reichel 2025

No specific timing documented. Two-week protocols used in animal models with daily administration.Timofeeva 2005

3. Detection in sport

ACE-031 is prohibited under WADA S4.3 (Myostatin Inhibitors). Gel electrophoresis and Western blotting using ACVR2B-specific antibodies can detect the ~58.4 kDa protein in biological samples.Reichel 2025

Elderly individuals may exhibit different enzyme normalization patterns than younger cohorts, based on rat age-stratified findings.Timofeeva 2005

4. Clinical trial route

Phase 2 protocol used subcutaneous injections at weekly or biweekly intervals. Exact dosing protocols remain unpublished.

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