Ostarine (MK-2866, Enobosarm) is a nonsteroidal selective androgen receptor modulator (SARM) originally developed by GTx Inc., one of the earliest and most-studied SARMs, with a more developed human clinical trial…
🔬 Studied for: Muscle-Wasting Research
💊 Also studied for: Bone-Density Research
🧪 Not FDA-approved — sold strictly for laboratory research
📈 No standardized human dosage established in published literature
Ostarine (MK-2866, Enobosarm) is a nonsteroidal selective androgen receptor modulator (SARM) originally developed by GTx Inc., one of the earliest and most-studied SARMs, with a more developed human clinical trial record than most other compounds in the class.
Ostarine binds the androgen receptor and is studied for producing tissue-selective anabolic effects in muscle and bone with reduced activity in other androgen-sensitive tissue compared to testosterone, the shared mechanistic premise of the SARM drug class.
These are effects Ostarine (MK-2866) has been studied for in available preclinical and early research — not claims about guaranteed outcomes.
Ostarine has been studied in Phase 2 human clinical trials for cancer cachexia and age-related muscle loss, where trial data showed increases in lean body mass, giving it one of the stronger human-trial safety and efficacy records among SARMs.
Because androgen receptor activation also affects bone tissue, Ostarine has additionally been studied in models and trials examining bone mineral density, an area of interest for its potential use in osteoporosis-adjacent research.
Doses used in published Phase 2 clinical trials are documented in that trial literature and are specific to those regulated study protocols; no FDA-approved commercial dosage exists for Ostarine research material.
Compound X does not provide dosing recommendations. Ostarine (MK-2866) is sold for laboratory research use only and is not intended for human consumption.
Ostarine's Phase 2 trials reported it was generally well tolerated at studied doses over the trial periods, though it has not completed the Phase 3 program required for FDA approval, so no approved product exists. It is banned by the World Anti-Doping Agency, and case reports outside formal trials have raised concerns about liver enzyme changes and suppression of natural testosterone production.
No. Ostarine (MK-2866) is not FDA-approved for any indication and is sold strictly as a research chemical, not a medication or dietary supplement.
Muscle-Wasting Research — Ostarine has been studied in Phase 2 human clinical trials for cancer cachexia and age-related muscle loss, where trial data showed increases in lean body mass, giving it one of the stronger human-trial safety and efficacy records among SARMs.
In the US, UK, Canada and Australia, Ostarine (MK-2866) is generally sold labeled "for research use only, not for human consumption." It is not approved as a dietary supplement or medication in any of these countries.
Ostarine/Enobosarm clinical trial data is indexed on PubMed under "Ostarine MK-2866 Enobosarm clinical trial" and "GTx SARM cachexia."
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