MK-0773 is a selective androgen receptor modulators (SARMs) that binds to AR with an IC50 of 6.6 nM. IC50: 6.6 nM (AR)
The IC50 of MK-0773 binding to AR is increased 3.5-fold in the presence of 25% rat serum and 13-fold in the presence of 25% human serum, indicating that it binds to serum proteins. The affinity of MK-0773 for AR across species is evaluated using COS cells transfected with AR, and IC50 values are very similar in four species (rat, 0.50 nM; dog, 0.55 nM; rhesus, 0.45 nM; human, 0.65 nM)[1].
MK-0773 (6 and 80 mg/kg, s.c.) produces exposure-related stimulatory effects on cortical BFR and LBM in the OVX rat model. MK-0773 (5, 15, and 80 mg/kg, s.c.) increases seminal vesicle weights, and has reduced effects on the prostate. The partial agonism and tissue selectivity of MK-0773 does not translate into differential effects on lipid metabolism in OVX rats[1].
[1]. Schmidt A, et al. Discovery of the selective androgen receptor modulator MK-0773 using a rational development strategy based on differential transcriptional requirements for androgenic anabolism versus reproductive physiology. J Biol Chem. 2010 May 28;285