MK-2866 (Capsules)

MK-2866, commonly known as ostarine or enobosarm (GTx-024), is a potent nonsteroidal selective androgen receptor modulator developed by GTx Inc [1]. This compound binds to the androgen receptor with high affinity (Ki approximately 3-5 nM), activating AR-dependent transcription while maintaining tissue selectivity [2]. Unlike traditional hormone-based compounds, ostarine demonstrates selective anabolic effects in muscle and bone tissue while minimizing androgenic effects in reproductive tissues such as prostate and seminal vesicles [3]. Preclinical and limited clinical-stage research has examined its applications in muscle wasting conditions, cachexia, sarcopenia, osteoporosis, and stress urinary incontinence. The compound shows oral bioavailability suitable for mechanistic research into androgen receptor pharmacology and tissue-selective signaling.

Chemical Structure and Identification

• Compound Name: MK-2866 (Ostarine)
• Per capsule: 12.5 mg per capsule
• Molecular Formula: C₁₉H₁₄F₃N₃O₃
• Molecular Weight: 389.33 g/mol
• CAS Number: 841205-47-8

Research Applications

• Androgen Receptor Pharmacology: Mechanistic investigation of nonsteroidal androgen receptor binding activity and AR-dependent transcription [1][2]
• Muscle Protein Synthesis: Preclinical studies of lean body mass development, muscle fiber growth, and strength parameters in cell-based models [2][3]
• Bone Metabolism: Research into bone mineral density, osteoblast function, and bone anabolism mechanisms in experimental systems [3]
• Muscle Wasting Models: Evaluation in cachexia, disuse atrophy, and age-related muscle loss preclinical research paradigms [4]
• Tissue-Selective Receptor Effects: Comparative analysis of anabolic versus androgenic responses across tissue types in controlled laboratory settings [1][2]

Reference Citations

1. MedKoo Biosciences – Ostarine (MK-2866) Selective Androgen Receptor Modulator Information | https://www.medkoo.com/products/5709
2. InvivoChem – MK-2866 (GTx-024) Androgen Receptor Modulator with Tissue Selectivity | https://www.invivochem.com/mk-2866-gtx-024.html
3. PubMed (40514634) – A Computational and In Vitro Appraisal of Ostarine to Target Androgen Receptor in Cell Models | https://pubmed.ncbi.nlm.nih.gov/40514634/
4. Journal of Medicinal Chemistry – Nonsteroidal selective androgen receptor modulators: dissociating anabolic and androgenic activities | https://pubmed.ncbi.nlm.nih.gov/
5. MedChemExpress – Ostarine (MK-2866) Research Applications in Myogenic Differentiation | https://www.medchemexpress.com/ostarine.html

Important Regulatory Notice

These products are for research use only and are not intended for human consumption, therapeutic use, or diagnostic purposes. All compounds described herein have not been approved by the FDA for human use. These products are strictly intended for in vitro laboratory research and analytical purposes when conducted by qualified research professionals in licensed facilities. Users are responsible for ensuring compliance with all applicable laws regarding purchase and use of these materials.