BMS 986122 is a positive allosteric modulator of μ-opioid receptors that increases β-arrestin recruitment stimulated by endomorphin 1 in U2OS-OPRM1 human osteosarcoma cells expressing μ-opioid receptors (EC50 = 3 μM).

ML-335 is a μ-δ isomer-targeted agonist, a μOR-δOR-biased ligand that can serve as a scaffold for the development of unique types of (isomer-biased) drugs.

BTRX-335140 is a potent and selective, orally active κ opioid receptor (KOR) antagonist, has antagonist activity for κOR, μOR and δOR with IC50 values of 0.8 nM, 110 nM, and 6500 nM, respectively.