Side-by-side · Research reference

ACE-031vsKisspeptin-10

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

BPhase 2HUMAN-REVIEWED10/41 cited

ACE-031

ActRIIB-Fc Fusion · Phase 2 Halted

Phase 2Highest trial stage

2011Development halted

~58.4 kDaMolecular weightReichel 2025

SQ · Weekly dosing investigated

Kisspeptin-10

Neuropeptide · GPR54 Agonist

GnRH pulse generatorPrimary roleSilva 2026

Phase 1/2Clinical stage

GPR54/Kiss1RTarget receptorRønnekleiv 2026

IV / SQ · Investigational

01Mechanism of Action

Parameter

ACE-031

Kisspeptin-10

Primary target

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

GPR54/Kiss1R on hypothalamic GnRH neuronsRønnekleiv 2026 Collado-Sole 2026

Pathway

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

Kisspeptin → GPR54 activation → GnRH neuronal depolarization → Pulsatile GnRH release → Pituitary LH/FSH secretionLages 2026 Rønnekleiv 2026

Downstream effect

Disinhibition of myogenic signaling, increased skeletal muscle mass and strength

Pulsatile LH surge, FSH elevation, gonadal steroidogenesis, gametogenesis initiationLages 2026

Feedback intact?

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Yes — integrates estradiol, leptin, and IGF-1 signals to modulate HPG axisSilva 2026 Rønnekleiv 2026

Origin

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

C-terminal decapeptide of KISS1 gene product; retains full biological activity of longer kisspeptin isoforms

Antibody development

—

02Dosage Protocols

Parameter

ACE-031

Kisspeptin-10

Clinical dosing

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

Phase 2 DMD trial protocol not fully published.

—

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

—

Evidence basis

Phase 2 trial discontinued — incomplete dataset

Phase 1/2 trials

Half-life

Days to weeks (Fc-fusion typical kinetics)

IgG1-Fc domain confers extended circulation time.

Short (minutes)

Rapid clearance; pulsatile dosing mimics physiological GnRH pulse frequency.

Duration investigated

12–24 weeks (trial cut short)

—

Clinical trial dose

—

Phase 1/2 investigational

Dosing protocols vary by indication (hypothalamic amenorrhea, IVF trigger).

Route

—

IV or SQ administration

IV preferred in controlled trials for precise pulsatile delivery.

04Side Effects & Safety

Parameter

ACE-031

Kisspeptin-10

Epistaxis (nosebleeds)

Significant incidence in Phase 2 DMD trial — primary safety signal

—

Telangiectasia

Dilated capillaries / spider veins observed

—

Vascular abnormalities

Mechanism: ActRIIB/ALK1 pathway disruption affects vascular homeostasis

—

Injection site reactions

Local erythema, induration (biologics class effect)

—

Antibody development

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

—

Black market contaminants

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

—

Ovarian hyperstimulation

—

Theoretical risk with supraphysiological dosing in fertility protocols

Headache

—

Mild, reported in early-phase trials

Nausea

—

Transient GI symptoms with IV bolus

Hot flashes

—

Vasomotor symptoms from LH surge

Injection site reaction

—

Erythema, mild discomfort (SQ route)

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

Kisspeptin-10

·Active pregnancy
·Hormone-sensitive malignancy (breast, ovarian, endometrial)

Relative Contraindications

ACE-031

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

Kisspeptin-10

·Polycystic ovary syndrome (PCOS) without monitoring
·Uncontrolled thyroid dysfunction

05Administration Protocol

Parameter

ACE-031

Kisspeptin-10

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.

Reconstitute with sterile water or saline per protocol. Gently swirl — do not shake. Solution should be clear and colorless.

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

IV infusion for pulsatile delivery in clinical trials; SQ for outpatient protocols. IV allows precise temporal control of GnRH pulse frequency.

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

Pulsatile dosing (e.g., every 60–90 min) mimics physiological GnRH pulse generator. Single-bolus protocols used for LH surge induction in fertility research.

4. Clinical trial route

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

Serial LH, FSH, estradiol measurements to confirm HPG axis activation. Ultrasound monitoring for ovarian response in fertility applications.

5. Storage

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Lyophilized: store at 2–8 °C, light-protected. Reconstituted: refrigerate, use within 24–48 hours per protocol.