HU-308 (also known as HU308, PPP-003 and ARDS-003) is a cannabidiol (CBD)-derivative drug that acts as a potent cannabinoid agonist. It is highly selective for the cannabinoid-2 receptor (CB2 receptor) subtype, with a selectivity more than 5,000 times greater for the CB2 receptor than the CB1 receptor. The synthesis and characterization of HU-308 took place in the laboratory of Raphael Mechoulam at the Hebrew University of Jerusalem (the HU in HU-308) in the late 1990s. The pinene dimethoxy-DMH-CBD derivative HU-308 was identified as a potent peripheral CB2-selective agonist in studies in 1990 and 1999.