Clocinnamox (CCAM or C-CAM; developmental code name NIH-10443) is a selective and irreversible antagonist of the ü-opioid receptor. Closely related compounds include methocinnamox (MCAM) and methoclocinnamox (MCCAM). They were derived via structural modification of buprenorphine. Clocinnamox was first described in the scientific literature by 1992.