GPR61 Inverse agonist 3 is a selective compound capable of crossing the blood-brain barrier, functioning as an inverse agonist for GPR61. It demonstrates an IC50 of 4.0 nM for human receptors and 8.8 nM for mouse receptors, with a Ki of 0.34 nM in humans and 1.1 nM in mice. This compound disrupts the GPR61-Gαs protein interaction, thus eliminating the constitutive activity of GPR61. Additionally, GPR61 Inverse agonist 3 moderately inhibits the GABAA chloride ion channel and PDE3A1, with IC50 values of 4.6 μM and 8.9 μM, respectively. When co-administered with pan-CYP inhibitors, it shows no functional effect on food intake in adult mice. GPR61 Inverse agonist 3 can be utilized in research related to cachexia/sarcopenia.