What is the difference between ACE-031 and Ipamorelin?

ACE-031: Soluble form of activin type IIB receptor (ActRIIB-Fc fusion protein) that acts as a myostatin and activin trap. Blocks the primary signals that limit muscle growth by sequestering myostatin, activin, and related ligands before they reach cell surface receptors. Phase 2 trials in Duchenne muscular dystrophy demonstrated significant lean mass increases. Ipamorelin: Ipamorelin is a selective growth hormone secretagogue (GHS) and ghrelin receptor agonist. It stimulates GH release with high selectivity — minimal cortisol or prolactin elevation compared to older GHRPs. Widely used in research protocols for body composition, sleep quality, and recovery. Both are in the Performance & Growth Hormone category but differ in mechanism, dosing, and research evidence — see the full comparison.

Can you take ACE-031 and Ipamorelin together?

There is no specific, well-documented interaction rule for combining ACE-031 and Ipamorelin in the aggregated research reviewed. Combining peptides should only be considered under professional supervision. This is not medical advice.

Which is better researched, ACE-031 or Ipamorelin?

ACE-031 is currently investigational (in trials) and Ipamorelin is investigational (in trials). "Better researched" depends on your research goal — review each profile's cited sources.

Performance & Growth Hormone · Comparison

ACE-031 vs Ipamorelin

A neutral, side-by-side comparison of two performance & growth hormone peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.

ACE-031

Investigational (in trials)

Soluble form of activin type IIB receptor (ActRIIB-Fc fusion protein) that acts as a myostatin and activin trap. Blocks the primary signals that limit muscle growth by sequestering myostatin, activin, and related ligands before they reach cell surface receptors. Phase 2 trials in Duchenne muscular dystrophy demonstrated significant lean mass increases.

Full profile

Ipamorelin

Investigational (in trials)

Ipamorelin is a selective growth hormone secretagogue (GHS) and ghrelin receptor agonist. It stimulates GH release with high selectivity — minimal cortisol or prolactin elevation compared to older GHRPs. Widely used in research protocols for body composition, sleep quality, and recovery.

Full profile

	ACE-031	Ipamorelin
Category	Performance & Growth Hormone	Performance & Growth Hormone
Also known as	ACVR2B-Fc, ActRIIB-Fc fusion protein	NNC 26-0161, Ipamorelin acetate
Evidence	Investigational (in trials)	Investigational (in trials)
Dosing range	0.3mg/kg–3mg/kg mg/kg, every 2–4 weeks (subcutaneous injection)	100mcg–300mcg mcg, 1–3x daily (typically pre-sleep and/or pre-workout)
Administration	Subcutaneous injection	Subcutaneous injection, Intramuscular injection
Key side effects	Nosebleeds (epistaxis — most common reported AE), Telangiectasia (visible small blood vessel dilation), Gum bleeding, Elevated hemoglobin	Water retention (mild), Tingling / numbness in extremities, Increased appetite, Headache (transient)
Cited sources	2 references	3 references

Key differences

Administration: ACE-031 — Subcutaneous injection; Ipamorelin — Subcutaneous injection, Intramuscular injection.
Dosing units differ: ACE-031 is dosed in mg/kg, Ipamorelin in mcg — they operate at different scales.
Frequency: ACE-031 is typically every 2–4 weeks (subcutaneous injection); Ipamorelin is 1–3x daily (typically pre-sleep and/or pre-workout).
Research depth: this profile cites 2 sources for ACE-031 vs 3 for Ipamorelin.

How each works

ACE-031

ACE-031 functions as a decoy receptor, binding myostatin, activin A/B, GDF-11, and BMP-9 in circulation before they can activate cellular ActRIIB receptors. In the Duchenne muscular dystrophy Phase 2 trial, ACE-031 produced meaningful lean body mass increases but was halted due to vascular side effects (epistaxis, telangiectasia) requiring dose and safety optimization.

Ipamorelin

Ipamorelin selectively stimulates GH release via the ghrelin receptor (GHS-R1a) without significantly elevating ACTH or cortisol — the feature that distinguishes it from GHRP-6 and GHRP-2 (Raun et al., 1998, in swine/rodent models). Human data are limited: a PK study in 40 volunteers established a ~2-hour half-life (Gobburu et al., 1999), and a Phase 2 trial for postoperative ileus (Beck et al., 2014) failed its primary endpoint. It is not FDA-approved, and claims about body composition or recovery are extrapolated from GH physiology, not human outcome trials.

Read the full ACE-031 profile Read the full Ipamorelin profile

This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.