Peptide Comparison
SM-130686vsMK-677 (Ibutamoren)
Experimental oral growth hormone secretagogue with anabolic potential from preclinical research
The oral growth hormone secretagogue that tricks your body into producing more GH — no needles required.
At a Glance
Quick
comparison
Dose Range
SM-130686
5–20 mg
MK-677 (Ibutamoren)
10–25 mg
Frequency
SM-130686
Multiple times daily
MK-677 (Ibutamoren)
Once daily
Administration
SM-130686
Oral capsule or powder
MK-677 (Ibutamoren)
Oral (capsule or liquid)
Cycle Length
SM-130686
8-12 weeks
MK-677 (Ibutamoren)
8-12 weeks
Onset Speed
SM-130686
Moderate (1-2 weeks)
MK-677 (Ibutamoren)
Moderate (1-2 weeks)
Evidence Level
SM-130686
Moderate human trials (Phase 1-2)
MK-677 (Ibutamoren)
Moderate human trials (Phase 1-2)
Efficacy
Benefit
ratings
Muscle and Strength
Recovery and Performance
Metabolic Health
Muscle and body composition
Recovery and athletic performance
Sleep quality and metabolic health
Technical Data
Compound
specifications
SM-130686
Molecular Formula
C22H24Cl2F3N3O3
Molecular Weight
506.3 g/mol (as HCl salt)
Half-Life
Not published in humans (preclinical only)
Bioavailability
28% in rats (oral administration)
CAS Number
259667-25-9
MK-677 (Ibutamoren)
Molecular Formula
C27H36N4O5S
Molecular Weight
528.7 g/mol
Half-Life
4-6 hours (IGF-1 elevation persists ~24 hours)
Bioavailability
High oral bioavailability
CAS Number
159634-47-6
Applications
Best
suited for
SM-130686
Lean Mass Building in Trained Athletes
SM-130686 targets GHS-R to stimulate GH release, which supports anabolic processes. Preclinical studies in rats showed significant increases in fat-free mass and body weight when combined with resistance training principles.
Age-Related GH Decline
As a GHS-R agonist, SM-130686 may help restore physiological GH secretion in adults experiencing age-related decline. The oral route is convenient for long-term administration.
Recovery and Performance
GH supports tissue repair, collagen synthesis, and recovery. May benefit individuals engaged in intensive resistance training or athletic performance work.
MK-677 (Ibutamoren)
Older Adults (60+) Seeking Body Composition Improvements
MK-677 was designed for aging populations. It restores GH and IGF-1 to youthful levels, increases lean mass, and improves physical function in people over 60. A 2-year clinical trial showed a 1.1 kg gain in fat-free mass with only modest fat gain—ideal for maintaining strength in older age.
Athletes and Fitness Enthusiasts Wanting Recovery Support
Oral dosing makes MK-677 convenient for athletes. It enhances muscle protein synthesis, speeds recovery after intense training, and supports lean mass building without the hassle of injections.
People with Chronic Wasting or Protein Deficiency
Clinical trials show MK-677 helps treat protein-energy wasting in kidney disease and other conditions. It stimulates appetite (a feature in these populations) and preserves muscle tissue—making it useful for those losing mass despite good nutrition.
Safety Profile
Side
effects
SM-130686
Common
- Appetite stimulation
- Transient water retention
Uncommon
- Joint or muscle aches
- Transient changes in blood glucose
Serious
- Potential carpal tunnel syndrome
- Unknown effects on tumor growth
MK-677 (Ibutamoren)
Common
- Increased appetite
- Mild water retention or edema
- Elevated fasting glucose
Uncommon
- Joint or muscle pain
- Carpal tunnel syndrome or nerve compression symptoms
- Mild nausea or digestive upset
Serious
- Glucose dysregulation and diabetes risk
Research Status
Safety
& evidence
SM-130686
Evidence Level
Moderate human trials (Phase 1-2)
FDA Status
Research compound
Safety Overview
SM-130686 is a research compound that has never been tested in humans. All safety and efficacy data come from animal studies (primarily rats). No human clinical trials have been conducted. Use carries unknown risks. Potential side effects based on GH physiology and limited preclinical work.
Contraindications
- xPregnancy or breastfeeding (no safety data)
- xActive cancer (GH stimulation may be contraindicated)
- xUncontrolled diabetes (may affect glucose metabolism)
- xSevere cardiovascular disease (GH effects on heart not fully characterized)
MK-677 (Ibutamoren)
Evidence Level
Moderate human trials (Phase 1-2)
FDA Status
Research compound
Safety Overview
MK-677 has been studied in hundreds of humans over 2+ years and is generally well tolerated. Most side effects are mild and manageable, especially with lower starting doses. The lack of injection requirement makes it safer than injectable GH in terms of infection risk and sterility concerns. However, it is not FDA approved and should be viewed as a research compound.
Contraindications
- xUncontrolled diabetes or severe glucose dysregulation
- xActive cancer or high cancer risk requiring caution with IGF-1 elevation
- xPregnancy or breastfeeding
Decision Guide
Which is
right for you?
Choose SM-130686 if...
- Lean mass building (theoretical)
- Strength development (preclinical evidence)
- Body composition improvement (animal studies)
Choose MK-677 (Ibutamoren) if...
- Building lean muscle mass and strength
- Improving overall body composition in aging adults
- Enhancing athletic recovery and performance
- Supporting metabolic health and fat loss