AT-076 is a so-called opioid "pan" antagonist and is the first reasonably balanced antagonist known of all four opioid receptor types. It acts as an antagonist of all four types of opioid receptor, behaving as a competitive antagonist of the μ-opioid receptor (Ki = 1.67 nM) and δ-opioid receptor (Ki = 19.6 nM) and as a noncompetitive antagonist of the κ-opioid receptor (Ki = 1.14 nM) and nociceptin receptor (NOP, Ki = 1.75 nM). AT-076 was derived from the κ-opioid receptor antagonist JDTic, which showed affinity for NOP, by removal of two methyl groups from the piperidine ring. This increased affinity for NOP 10-fold relative to the parent compound.
See also AT-121 Cebranopadol Buprenorphine BU09059
References