Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Head-to-head comparison of AC-262536 and GSK-2881078 — mechanism, side effects, legal status, and pricing.
AC-262536 is a non-peptide nonsteroidal selective androgen receptor modulator (SARM) with an azabicyclooctane naphthalene-carbonitrile structure. It acts as a partial AR agonist, showing tissue-selective anabolic effects in preclinical models. No human trials have been conducted, and it is not FDA-approved. SARMs are prohibited in athletic competition under WADA category S1.2.
GSK-2881078 is a nonsteroidal selective androgen receptor modulator (SARM) of the indole-5-carbonitrile chemotype, developed by GlaxoSmithKline to produce tissue-selective anabolic effects in skeletal muscle with reduced activity in androgen-sensitive tissues. It has been studied in three human clinical trials (Phase I and Phase IIa) but has never been approved for any indication and is not in active further development. SARMs as a pharmacological class are prohibited in sport at all times under WADA category S1.2 (Other Anabolic Agents), though GSK-2881078 is not individually named in reviewed WADA documents.
AC-262536
GSK-2881078
Category
Legal Status
Mechanism
Side Effects
COA-verified vendors · trust score ≥70 required · single-vial price — bulk/bundle deals may be lower
AC-262536
GSK-2881078
COA corpus from Disclosed Labs — independently tested batches only.
AC-262536
No COA data yet.
Submit testing data →GSK-2881078
2
COAs
99.6%
Avg purity
2
Labs
No human data exist. All pharmacology derives from a single 2008 preclinical publication. In castrated male rats dosed chronically for two weeks, AC-262536 significantly increased levator ani muscle growth and suppressed elevated luteinizing hormone, while producing only weak effects on prostate and seminal vesicle weight compared to testosterone. The compound has also been included in validated analytical panels for SARM residue surveillance in bovine muscle tissue, reflecting its presence in food-safety monitoring rather than therapeutic development.
Human data are the most extensive of any compound in the SARM class: a Phase I first-in-human study in healthy men and postmenopausal women (Clark 2017) established dose-proportional systemic exposure and a long half-life (>100 hours) supporting once-daily dosing; a Phase I dose-escalation study in adults ≥50 years (Neil 2018) showed dose-dependent lean body mass gains (~3.39 kg in women, ~1.76 kg in men versus placebo at 8 weeks) accompanied by transient ALT elevations and 30–45% HDL-cholesterol reductions at the highest doses, both reversible on stopping treatment; and a Phase IIa randomized controlled trial in 97 COPD patients with muscle weakness (Mohan 2023) demonstrated increased lean body mass and leg-press strength (more consistently in men) over 13 weeks, with reversible HDL-C reduction and transient ALT increases as the main treatment-related safety signals. No peer-reviewed animal or in-vitro pharmacology/toxicology data for GSK-2881078 were located via PubMed or PubChem.
Key references
AC-262536 and GSK-2881078 are both in the Performance category and may have overlapping mechanisms. Researchers should review both profiles carefully, understand the mechanisms of action, and monitor the relevant biomarkers when combining compounds in the same class. As always, consult a licensed healthcare provider before making any decisions about combining research compounds.
This platform provides informational tools only, not medical advice. This comparison is for educational purposes only. Consult a licensed provider.
Contraindications
Lab Testing