 TIK-301 (PD-6735, LY-156,735) has been in phase II clinical trial in the United States (US) since 2002.The FDA granted TIK-301 orphan drug designation in May 2004, to use as a treatment for circadian rhythm sleep disorder in blind individuals without light perception and individuals with tardive dyskinesia.In 2005 ramelteon (Rozerem®) was approved in the US indicated for treatment of insomnia, characterized as difficulty with falling asleep, in adults.