Peptides Codex
ENFR
← Home
ActRIIB decoy-receptor fusion protein

ACE-031

ACE-031 is an engineered decoy receptor made by fusing the extracellular domain of the activin receptor type IIB (ActRIIB) to an IgG1 Fc fragment. It binds myostatin and related ligands to block their signaling. It is investigational, its clinical development was halted, and it is not approved; this page is educational only.

By The Peptides Codex Editorial TeamReviewed July 10, 2026
Length
n/a
Class
ActRIIB decoy-receptor fusion protein
Function
Sequesters myostatin and related ligands away from ActRIIB
Context
Investigational compound; development halted, not approved

A soluble decoy receptor designed to intercept myostatin before it signals.

Also known as: ActRIIB-IgG1 · ramatercept

Part of the Growth hormone & IGF peptides cluster

Overview

ACE-031 is an engineered decoy receptor made by fusing the extracellular domain of the activin receptor type IIB (ActRIIB) to an IgG1 Fc fragment. It binds myostatin and related ligands to block their signaling. It is investigational, its clinical development was halted, and it is not approved; this page is educational only.

Source & context

Biological / chemical source: Recombinant fusion of the ActRIIB extracellular domain with an IgG1 Fc

Primary research or clinical context: Investigational compound; development halted, not approved

Decoy-receptor mechanism

Myostatin normally binds ActRIIB on muscle to restrain growth. ACE-031 presents a soluble copy of the receptor's ligand-binding domain, so it captures myostatin and related TGF-beta ligands in circulation before they reach cell-surface receptors. The Fc fusion prolongs its half-life, a common biologic-engineering approach.

Trial history and status

ACE-031 was tested in a randomized trial in boys with Duchenne muscular dystrophy (NCT01099761), which was stopped early based on preliminary safety findings. It never reached approval and remains investigational. This summary describes the molecule and its history for education and makes no efficacy or safety claims.

FAQ about ACE-031

What is ACE-031?+

ACE-031 is an engineered decoy receptor made by fusing the extracellular domain of the activin receptor type IIB (ActRIIB) to an IgG1 Fc fragment. It binds myostatin and related ligands to block their signaling. It is investigational, its clinical development was halted, and it is not approved; this page is educational only.

Is ACE-031 an approved medicine?+

ACE-031 is discussed here as a research / educational topic. Investigational compound; development halted, not approved. This is not medical advice.

What is the typical length of ACE-031?+

ACE-031 is not a classic amino-acid chain peptide in the same sense; see the profile for classification details.

Related peptides

Larazotide
Tight-junction regulator peptide
Larazotide (larazotide acetate, AT-1001) is a synthetic eight-amino-acid peptide studied as a regulator of intestinal tight junctions, the seals between gut lining cells. It was investigated in celiac disease research. Its Phase 3 program was discontinued and it is not approved; this page is educational only.
Lixisenatide
Incretin mimetic (GLP-1 receptor agonist)
Lixisenatide is a synthetic GLP-1 receptor agonist built on the exendin-4 scaffold rather than on human GLP-1. Marketed as Lyxumia and Adlyxin, it is an approved prescription medicine in the EU and United States and a useful case study in how venom-derived peptides are adapted into once-daily therapeutics.
Calcitonin
Hormone
Calcitonin is a 32-amino-acid peptide hormone secreted by thyroid C-cells that helps regulate blood calcium. Salmon calcitonin has been used as an approved medicine in several jurisdictions.
CGRP
Neuropeptide
CGRP (calcitonin gene-related peptide) is a 37-amino-acid neuropeptide produced by alternative splicing of the calcitonin gene. It is a potent vasodilator and a major focus of migraine and pain-signaling research.

References & further reading

  1. 1.Wikipedia — Decoy receptors (ACE-031)
  2. 2.ClinicalTrials.gov — ACE-031 in Duchenne muscular dystrophy (NCT01099761)
Disclaimer: Educational content only. Not medical advice. Not instructions for human use. Research peptides and unapproved products may be restricted or illegal to market for human consumption in your jurisdiction. Consult qualified professionals and applicable law.
You might also like: All peptides · Atlas · Research · Tools
Cite this: Peptides Codex — ACE-031 educational profile.
Tip: Use browser print (Ctrl/Cmd + P) for a clean PDF of this page.