LGD-3303

Muscle Growth & Body Composition

Also known as: LGD3303, Ligand 3303

Selective Androgen Receptor ModulatorsResearch phase: PreclinicalRegulatory: Not FDA-approved. Research chemical only. No human clinical trials.

Mechanism

LGD-3303 is an orally active SARM developed by Ligand Pharmaceuticals with strong anabolic effects on both muscle and bone. Preclinical studies show it can increase bone mineral density and lean muscle mass while maintaining selectivity over reproductive tissues.

Technical detail

LGD-3303 is a non-steroidal, orally bioavailable SARM developed by Ligand Pharmaceuticals that acts as a full agonist at the AR in muscle and bone tissue. In ovariectomized rat models, it demonstrated potent increases in femoral bone mineral density and cortical bone mass comparable to DHT, with concurrent anabolic effects on muscle. It exhibits tissue selectivity through differential AR cofactor recruitment. It was not advanced into clinical trials and remains a preclinical research compound.

Evidence

Pharmacokinetics and pharmacodynamics of LGD-3303 [9-chloro-2-ethyl-1-methyl-3-(2,2,2-trifluoroethyl)-3H-pyrrolo-[3,2-f]quinolin-7(6H)-one], an orally available nonsteroidal-selective androgen receptor modulator
Vajda et al. (2009) — J Pharmacol Exp Ther — PMID: 19017848
In castrated rats, LGD-3303 increased levator ani muscle activity while remaining only a partial agonist in prostate tissue and did not stimulate ventral prostate above intact levels, supporting tissue-selective anabolic activity that appeared independent of PK exposure profile.
emerging

Build a personalized protocol with LGD-3303 →