AM-1241, was developed at the University of Connecticut. AM-1241 was derived from the known non-selective indole class of cannabinoid receptor agonists represented by WIN55212-2 and JWH-015. Compared to earlier agonists that exhibited modest selectivities, AM-1241 exhibited 82-fold selectivity for CB2 over CB1 based on binding affinity assays. Using AM-1241, it was demonstrated that a selective CB2 receptor agonist provides relief of pain without the psychotropic effects produced by a pan-cannabinoid receptor agonist. After injection of AM-1241 into the hindpaw of a mouse, analgesic activity toward a thermal stimulus applied to the same paw was observed. Co-administration of a CB2 receptor antagonist blocked the effect, while a CB1 antagonist did not. The results of this initial study led researchers to investigate the use of a CB2 receptor selective agonist for the treatment of pain as well as other disease states that involve the CB2 receptor. It was found that AM-1241 inhibited nociception in CB+/+ mice, but not CB2+/+ littermates, providing strong evidence of its direct activation of CB2. AM-1241 was shown to dose-dependently inhibit capsaicin-induced release of the pain biomarker calcitonin gene-related peptide (CGRP) in rat spinal cord slices, a result that also suggests the presence of CB2 in neurons of the spinal cord. AM-1241 has being shown to be a promising target for the management of cancer pain.