Description
Andarine S4 Powder — Research Overview
Andarine (S4, GTx-007) is a non-steroidal SARM developed by GTx Inc. as part of the same research program that produced Ostarine. S4 has a distinct pharmacological profile — higher AR binding affinity than Ostarine with additional partial agonist activity at the retinal androgen receptor, a property unique among SARMs that has made it a tool compound for ocular androgen receptor research.
Mechanism of Action
S4 binds the androgen receptor with an affinity approximately 33% of testosterone, acting as a partial agonist. In muscle and bone, it activates anabolic AR programs including myosin heavy chain expression, satellite cell activation, and osteoblast differentiation. Its unique feature is partial AR agonism in retinal tissue — at higher doses, S4 produces reversible changes in light adaptation in rodents, related to its partial activity at retinal AR. This makes it a valuable tool for studying ocular AR biology.
Bone Density Research
S4 demonstrates anabolic effects on cortical bone mineral density in ovariectomised rat models, with dose-dependent improvements in femoral neck strength and trabecular bone volume comparable to testosterone propionate but without uterotrophic effects, supporting its classification as a tissue-selective AR ligand for bone research.
Powder Format for Research
Powder enables cell culture assays, receptor binding studies, and pharmacokinetic profiling. Soluble in DMSO (≥50mg/mL) and ethanol. Standard in vivo dosing: 3–10mg/kg/day oral in rodent studies.
Purity: ≥98% (HPLC verified) | Format: Lyophilised powder | Quantity: 1g
For research use only. Not for human consumption.






Dr. C. Chen –
Andarine S4 bulk powder for our large-scale SARM selectivity research. Purity confirmed >98.5% by HPLC. Powder dissolved cleanly in DMSO. COA detailed. Ideal format for high-volume research protocols.
H. Lindgren –
1g Andarine S4 powder — excellent for research applications requiring bulk material. Purity >98%. COA thorough. Fast delivery. Our AR binding panel showed expected tissue selectivity.
T. Boateng –
Good bulk Andarine powder. Purity >98.2%. Dissolved in DMSO cleanly. COA comprehensive. Practical format for high-volume SARM research.