LGD-3303 is a drug which acts as a selective androgen receptor modulator

Selective androgen receptor modulator

Selective androgen receptor modulators or SARMs are a novel class of androgen receptor ligands. They are intended to have the same kind of effects as androgenic drugs like anabolic steroids but be much more selective in...

, with good oral bioavailability. It is a selective agonist for the androgen receptor

Androgen receptor

The androgen receptor , also known as NR3C4 , is a type of nuclear receptor that is activated by binding of either of the androgenic hormones testosterone or dihydrotestosterone in the cytoplasm and then translocating into the nucleus...

, producing functional selectivity

Functional Selectivity

Functional selectivity is the ligand-dependent selectivity for certain signal transduction pathways in one and the same receptor. This can be present when a receptor has several possible signal transduction pathways...

 with effective dissociation of anabolic and androgen

Androgen

Androgen, also called androgenic hormone or testoid, is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of male characteristics in vertebrates by binding to androgen receptors...

ic effects, acting as a partial agonist for androgenic effects, but a full agonist for anabolic effects. It has been investigated as a possible treatment for osteoporosis

Osteoporosis

Osteoporosis is a disease of bones that leads to an increased risk of fracture. In osteoporosis the bone mineral density is reduced, bone microarchitecture is deteriorating, and the amount and variety of proteins in bone is altered...

, and was shown in animal studies to enhance the effectiveness of a bisphosphonate

Bisphosphonate

Bisphosphonates are a class of drugs that prevent the loss of bone mass, used to treat osteoporosis and similar diseases...

drug.