NRA-0160 is a selective dopamine D4 receptor antagonist, with a Ki value of 0.48 nM and with negligible affinity for dopamine D2 receptor (Ki: >10000 nM), D3 receptor (Ki: 39 nM), rat 5-HT2A receptor (Ki: 180 nM) and rat α1 adrenoceptor (Ki: 237 nM).
ABT-670 is a selective, oral bioavailable agonist of dopamine D4 receptor, with EC50 of 89 nM, 160 nM, and 93 nM for human?D4, ferret?D4, and rat?D4, respectively.