Tasimelteon

Tasimelteon (trade name Hetlioz) is a drug approved by the FDA solely for the treatment of non-24-hour sleep –wake disorder (often designated as N24HSWD) in totally blind adults. It is a selective agonist for the melatonin receptors MT1 and MT2 in the suprachiasmatic nucleus of the brain, similar to other members of the melatonin receptor agonist class of which ramelteon (2005) and agomelatine (2009) were the first approved. (In Vitro) :Tasimelteon (BMS-214778) has 2.1-4.4 times greater affinity for the MT2 receptor believed to mediate circadian rhythm phase-shifting (Ki=0.0692 nM and Ki=0.17 nM in NIH-3T3 and CHO-K1 cells, respectively), than for the MT1 receptor (Ki=0.304 nM and Ki=0.35 nM, respectively) . Tasimelteon has no appreciable affinity for more than 160 other pharmacologically relevant receptors and several enzymes.