ACE-031 vs Testosterone
Emerging vs FDA Approved
monitor Mechanism-based · 46% Both ACE-031 and Testosterone suppress the HPTA axis. Combined suppression deepens shutdown and extends recovery time. Plan PCT accordingly and monitor LH/FSH/testosterone.
Molecular Data
ACE-031 Testosterone
Weight — 288.42 Da (base)
Half-life 12-15 days ~8 days (cypionate)
Type Soluble activin receptor type IIB-Fc fusion protein Steroid hormone (C19H28O2)
Key Benefits
ACE-031
01 Significant lean mass increases (up to 1.7% in 29 days) observed in Phase 1 trials
02 Simultaneous reduction in fat mass alongside muscle gains
03 Long half-life (12-15 days) allows infrequent dosing
04 Broad TGF-beta ligand neutralization for robust anti-catabolic effects
05 Dose-dependent increases in thigh muscle volume confirmed by MRI
Testosterone
01 Restoration of normal testosterone levels in hypogonadal men
02 Increased lean muscle mass and strength
03 Improved bone mineral density and reduced fracture risk
04 Enhanced libido, sexual function, and erectile quality
05 Improved mood, energy, motivation, and cognitive clarity
06 Reduction in body fat percentage, particularly visceral fat
07 Increased red blood cell production and oxygen-carrying capacity
08 Improved insulin sensitivity and metabolic health markers
Dosing Protocols
ACE-031
0.5-3 mg/kg IV every 2 weeks (clinical research doses only) / Every 2 weeks
Phase 1 Research Protocol (Healthy Volunteers) 0.1-3 mg/kg Single IV dose
Phase 2 Research Protocol (DMD) 0.5-2.5 mg/kg Every 2 weeks
Testosterone
100-200 mg/week (TRT) / 1-2x per week (injectable)
TRT - Standard Replacement 100-200 mg/week 1-2x per week
TRT - Conservative Start 80-100 mg/week 2x per week (40-50 mg per injection)
TRT - Propionate Protocol 25-50 mg every other day Every other day or 3x per week
Performance Enhancement - Moderate 300-500 mg/week 2x per week
Performance Enhancement - Advanced 500-750 mg/week 2-3x per week
Side Effects
ACE-031
Nosebleeds (epistaxis) - most frequently reported adverse event
Gum bleeding
Telangiectasia (dilated small blood vessels visible on skin)
Skin erythema (redness)
Minor injection site reactions
Testosterone
Acne and oily skin (increased sebum production via DHT)
Water retention and bloating (estrogen-mediated)
Mild mood changes (irritability, increased assertiveness)
Increased hematocrit and hemoglobin (erythrocytosis)
Testicular atrophy (suppression of LH/FSH from exogenous testosterone)
Injection site pain, redness, or irritation
Increased body hair growth
Mild elevation in blood pressure
Contraindications
NEVER approved for human use - clinical development discontinued
History of bleeding disorders or vascular malformations
Concurrent anticoagulant or antiplatelet therapy
Known hypersensitivity to Fc fusion proteins
Pregnancy or breastfeeding
Prostate cancer (active or history of hormone-sensitive prostate cancer)
Breast cancer in males
Polycythemia (hematocrit above 54% at baseline)
Uncontrolled severe heart failure
Untreated severe obstructive sleep apnea
Desire for near-term fertility (without concurrent HCG/FSH)
Pregnancy or potential exposure to pregnant women (Category X)
Hypersensitivity to testosterone or any formulation components
Research Evidence
ACE-031 Testosterone
Status Emerging FDA Approved
References 4 studies 5 studies
Latest — June 2023
FDA Approved No Yes
This comparison is for educational and research purposes only. Consult a healthcare professional before use.