PF-04457845 is a potent and selective inhibitor of fatty acid amide hydrolase (FAAH), an enzyme responsible for the breakdown of endocannabinoids such as anandamide. By inhibiting FAAH, this compound increases endogenous levels of anandamide, which modulates pain, inflammation, and mood without the psychoactive effects associated with direct cannabinoid receptor agonists. It has been investigated for the treatment of chronic pain conditions, including osteoarthritis and neuropathic pain, due to its potential to provide analgesic effects through enhancement of the body’s natural pain-relief pathways. Additionally, it has shown promise in preclinical models for reducing inflammation and improving symptoms in conditions like anxiety and depression. Its selectivity and oral bioavailability make it a candidate for development in CNS-related disorders where modulation of the endocannabinoid system is beneficial.