Research Use
Also known as ACVR2B-Fc, Soluble activin receptor

Get a source-linked, educational explanation from this profile.

Complete Research Guide

Open each section for the available evidence. Gaps are stated rather than inferred.

Overview

ACE-031 is listed as myostatin inhibitor.

  • •Muscle mass increase (investigational)

Regulatory status: Development discontinued after safety signals.

Structure & Properties

Compound: ACE-031; also known as ACVR2B-Fc, Soluble activin receptor.

Pharmacologic class: Myostatin Inhibitor.

Known delivery routes: Subcutaneous.

Sequence, molecular weight, salt form, and excipient details are formulation-specific and are not listed unless verified by a manufacturer or laboratory COA.

How It Works

Soluble activin receptor type IIB fusion protein that sequesters myostatin and related ligands, removing the brake on muscle growth.

  • •Marked lean-mass gain in trials
  • •Reduced fat mass
Human Research

Evidence grade: Clinical RCT (Limited)

Clinical RCT (Limited). Phase II in Duchenne muscular dystrophy halted (2013).

Laboratory Research

Phase II in Duchenne muscular dystrophy halted (2013)

Preclinical findings describe biological plausibility, not proven benefit in people. Animal and laboratory doses do not translate directly to human use.

Processing & Interactions

Timing and exposure

No strict time-of-day requirement. Dose consistently at the same time daily and rotate injection sites. Follow the per-peptide dosing section above.

Potential interactions and combinations to avoid

  • •Avoid stacking with peptides that share the same receptor or mechanism without clinical guidance.
  • •Avoid combining with alcohol or immunosuppressants unless cleared by a clinician.

Absorption, half-life, metabolism, and clearance can vary by formulation and route. Use prescribing information when an approved product exists.

Safety & Precautions

Known or reported risks

  • •Nosebleeds and gum bleeding
  • •Telangiectasia
  • •Vascular/hematologic adverse events that ended development

Contraindications

  • •Bleeding disorders
  • •Vascular disease
  • •Pregnancy
  • •Any non-supervised use
  • •History of any solid tumor or hematologic malignancy
  • •Bleeding disorders, epistaxis, or anticoagulant/antiplatelet therapy (telangiectasia risk)
  • •Cardiac hypertrophy, cardiomyopathy, or valvular disease
  • •Pre-existing tendon or ligament pathology (strength gain outpaces connective-tissue adaptation)
  • •Bleeding disorders or anticoagulant therapy without physician guidance (injection-site haematoma)
  • •Active skin infection, cellulitis, or lipohypertrophy at intended injection sites
  • •Inability to maintain sterile technique or safe sharps disposal
  • •Not FDA-approved for human therapeutic use — no verified purity, sterility, or potency standards
  • •Immunocompromised or transplant patients (unverified sterility and immunogenicity risk)
  • •Concurrent participation in drug-tested sport (WADA prohibited or non-cleared substance)
  • •Known hypersensitivity or prior reaction to this compound or any excipient/diluent
  • •Pregnancy, attempting conception, or breastfeeding unless prescribed and monitored by a physician
  • •Children and adolescents with open growth plates (unless under specialist endocrine care)
  • •Active or recently treated malignancy without oncology clearance
  • •Use without a confirmed diagnosis, baseline labs, and licensed clinical supervision

Unknown long-term toxicity should be assumed where controlled human data are limited. Seek urgent care for a severe or unexpected reaction.

Administration & Studied Formulations

Reference range: 1–3 mg/kg (trial dosing)

Frequency: Every 2–4 weeks

Cycling: No safe consumer protocol exists; listed for reference only.

Subcutaneous (SubQ)

Default route for most research and therapeutic peptides — best absorption for reconstituted powder.

31G × 5/16" insulin syringe (U-100). 100 units = 1 mL. Pinch skin at abdomen (2" from navel), outer thigh, or love handle. Insert at 45–90°. Rotate sites daily to prevent lipohypertrophy. Alcohol-swab site, air-dry, inject slow, hold 5 sec.

Dosing information is educational context, not a personal recommendation. Approved products must follow their label and prescriber instructions.

Applications & Related Therapies

Potentially complementary measures

  • •Most peptides pair safely with baseline nutrition, sleep, and resistance training.

Clinical use should account for diagnosis, approved alternatives, nutrition, activity, sleep, rehabilitation, current medicines, and appropriate monitoring.

Cases, Considerations & Ethics

Decision framework: establish the clinical goal, confirm evidence quality and legal status, screen contraindications and interactions, compare approved alternatives, define monitoring and stopping criteria, and use shared decision-making with a licensed clinician.

Case evidence: individual reports cannot establish safety or effectiveness and should not outweigh controlled trials.

Ethics: informed consent should distinguish established care from experimental use, disclose uncertainty and cost, avoid overstated claims, and never substitute research products for medically necessary care.

What is ACE-031?

In plain words

ACE-031 is an experimental protein studied for increasing muscle mass. In the body, it traps myostatin and related proteins that normally limit muscle growth. Human trial evidence is limited, and it is not FDA-approved. Development stopped after safety problems involving blood vessels and bleeding, including nosebleeds and gum bleeding.

Technical definition

ACE-031 (ACVR2B-Fc) is an investigational myostatin inhibitor composed of a soluble activin receptor type IIB–Fc fusion protein. It sequesters myostatin and related ligands, reducing signals that normally restrain muscle growth; evidence for increasing muscle mass is limited to clinical randomized controlled trial data. ACE-031 is not FDA-approved, and development was discontinued after vascular and hematologic safety signals, including nosebleeds, gum bleeding, and telangiectasia (widened small blood vessels).

Function

Primary
Muscle mass increase (investigational)
Mechanism
Soluble activin receptor type IIB fusion protein that sequesters myostatin and related ligands, removing the brake on muscle growth.
Evidence
Clinical RCT (Limited)
Research
Phase II in Duchenne muscular dystrophy halted (2013)

Dosing

Range
1–3 mg/kg (trial dosing)
Frequency
Every 2–4 weeks
Route
Subcutaneous

Recommended Time of Day

Any consistent time, 1× weekly.

See “Timing & Interactions” below for full fasted/fed circumstances, what to avoid combining, and what pairs well.

Administration & Technique

Subcutaneous (SubQ)
Default route for most research and therapeutic peptides — best absorption for reconstituted powder.
Device31G × 5/16" insulin syringe (U-100). 100 units = 1 mL.
TechniquePinch skin at abdomen (2" from navel), outer thigh, or love handle. Insert at 45–90°. Rotate sites daily to prevent lipohypertrophy. Alcohol-swab site, air-dry, inject slow, hold 5 sec.

Injection & Application Sites

Front
Back
Subcutaneous (SubQ)
  • Abdomen — 2 in (5 cm) away from the navel, either side. Fastest, most consistent SubQ absorption.
  • Flank / love handle — Lateral fat pad above the hip. Good rotation site when the abdomen is tender.
  • Outer thigh — Upper outer quadrant, a hand-width below the hip. SubQ pinch at 45°.

Diagram is a general illustration, not a medical instruction. Rotate sites every injection, keep 1 in (2.5 cm) between recent sites, and avoid scars, moles, bruises and the navel area.

Cycling

No safe consumer protocol exists; listed for reference only.

Timing & Interactions

When to take
No strict time-of-day requirement. Dose consistently at the same time daily and rotate injection sites. Follow the per-peptide dosing section above.
Do not combine with
  • ·Avoid stacking with peptides that share the same receptor or mechanism without clinical guidance.
  • ·Avoid combining with alcohol or immunosuppressants unless cleared by a clinician.
Complements
  • ·Most peptides pair safely with baseline nutrition, sleep, and resistance training.

Storage & Reconstitution

Powder (Pre-Reconstitution)
Lyophilized powder: refrigerate 2–8°C for up to 24 months, or freeze at –20°C for extended storage. Keep sealed, desiccated, and protected from light.
After Reconstitution
After reconstitution with bacteriostatic water, refrigerate at 2–8°C and use within 28 days. Discard if cloudy, discolored, or precipitated.
Notes
Do not freeze after reconstitution — freeze/thaw cycles degrade most peptides.
Full BAC water & reconstitution guide →How to read a COA →

Reconstitution Calculator

Concentration
2.50 mg/mL
Volume per dose
0.100 mL
Insulin syringe
10.0 units (U-100)

1 mL = 100 units on a standard U-100 insulin syringe. Draw to the nearest 0.5 unit and confirm dosing with a clinician before injection.

Your Notes

Your Notes

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Benefits

  • ·Marked lean-mass gain in trials
  • ·Reduced fat mass

Risks

  • ·Nosebleeds and gum bleeding
  • ·Telangiectasia
  • ·Vascular/hematologic adverse events that ended development

Contraindications

  • ·Bleeding disorders
  • ·Vascular disease
  • ·Pregnancy
  • ·Any non-supervised use
  • ·History of any solid tumor or hematologic malignancy
  • ·Bleeding disorders, epistaxis, or anticoagulant/antiplatelet therapy (telangiectasia risk)
  • ·Cardiac hypertrophy, cardiomyopathy, or valvular disease
  • ·Pre-existing tendon or ligament pathology (strength gain outpaces connective-tissue adaptation)
  • ·Bleeding disorders or anticoagulant therapy without physician guidance (injection-site haematoma)
  • ·Active skin infection, cellulitis, or lipohypertrophy at intended injection sites
  • ·Inability to maintain sterile technique or safe sharps disposal
  • ·Not FDA-approved for human therapeutic use — no verified purity, sterility, or potency standards
  • ·Immunocompromised or transplant patients (unverified sterility and immunogenicity risk)
  • ·Concurrent participation in drug-tested sport (WADA prohibited or non-cleared substance)
  • ·Known hypersensitivity or prior reaction to this compound or any excipient/diluent
  • ·Pregnancy, attempting conception, or breastfeeding unless prescribed and monitored by a physician
  • ·Children and adolescents with open growth plates (unless under specialist endocrine care)
  • ·Active or recently treated malignancy without oncology clearance
  • ·Use without a confirmed diagnosis, baseline labs, and licensed clinical supervision

Regulatory

Development discontinued after safety signals

Veterinary Use (Pets)

No established veterinary protocol for ACE-031. Consult a licensed veterinarian before considering off-label use in any species.

Full veterinary reference →
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Educational reference only. Not medical advice. Consult a qualified clinician before starting any peptide protocol.

Non-FDA-approved peptides are for research use only. Not for human or animal consumption.