Tasimelteon Non-Addictive Drug for the Treatment of Sleep Disorders

One fourth of all chronic sleep disorders caused by a disruption in a person's "internal body clock" (regulates 24-hour schedule 1), otherwise known as circadian rhythm sleep disorders. "The National Institute of Health estimates that over 35 million Americans suffer from circadian rhythm disorders." 2 Also, estimated in 2007, approximately two-thirds of about 100 million people who took international flights from the United States probably suffered jet lag or change in normal sleep and wake time. 12 "Our daily activity and sleep rhythms are regulated by a control center in the hypothalamus region of the brain called the Suprachaismatic Nucleus (SCN) or layman's terms, the body clock." Normal signals received to our body clock when to shut down, prepare for sleep and when to produce active waking hormones (Melatonin hormone made by the pineal gland located just above the middle of the brain. 10). 2

Circadian rhythm disorders caused by many factors including: Change in time zone (when traveling), shift work hours from day time to night time (When waking up and working during night time hours instead during day light hours when the body normally functions, including normal hours to eat during the day. 3), as result of medication, pregnancy and changes in daily schedule. Also, circadian rhythm disorders occur during delayed sleep phase syndrome (DSPS - "People with DSPS tend to fall sleep at very late times and have difficulty waking up in time for work, school or social engagements.") and Advanced sleep Phase syndrome (Cause related to evening sleepiness, an early sleep onset, and waking up earlier than planned). 1 The onset of circadian rhythm disorders is predominant in women (three times the rate as men) beginning during early teenage years, and usually noticeable in men in their late teen years. Advanced circadian rhythm speeds up more in women internal clocks in their early 40's and men until they reach their 60's. 2

Common symptoms of circadian rhythm sleep disorders include: Tiredness or lack of energy in the morning hours, increase energy (mood) in the evening or late night hours, difficulty staying asleep or falling asleep and / or late night insomnia, concentrating, being alert or accomplishing tasks becomes difficult, and oversleeping or waking up is very hard. 2 Also, circadian rhythm disorders especially may prove more harmful to those who have high blood pressure and heart diseases. Besides disrupting the body's internal clock cause many to feel irritable, disoriented (After traveling through time zones), and depressed. 3

Current treatment for circadian rhythm includes combing cognitive behavior treatments, and external stimulus therapy such as chronotherapy or bright light therapy. 1

In December 2008 published online edition of The Lancet and available hard-copy, Dr. Shantha M.W. Rajaratnam and Dr. Elizabeth B. Kleman (Bright and Women's Hospital, Harvard Medical School, Boston MA, USA, Monash University, Australia) and colleagues wrote an article regarding the drug Tasimelteon, proven effective in phase two and three trials to treat circadian rhythm sleep disorders. 4 Tasimelteon mimics the effects of melatonin hormone regulating circadian rhythm. 11 Also, involved in the research study of Tasimelteon is Vandra Pharmaceuticals.5 According to results of phase two (39 people from two U.S. sites) and three (411 people from 19 U.S. Sites) trials who had received 20 mg, 50 mg, and 100 milligrams of Tasimelteon (or a placebo), 30 minutes before bedtime (during phase three) and five hour advance of sleep wake schedule with treatment before sleep: Medication reduced latency and improved sleep efficiency compared to taking a placebo. 4 Observed during trial study: Participants took an average of seven minutes to fall sleep, compared to eleven minutes before the trial and twenty-two minutes for those receiving a placebo. 8 During phase three trial the positive effects of Tasimelteon persisted for four weeks (duration of the study), and importantly first night of treatment positive results observed. 6

The authors of the study stated: "By simultaneously improving sleep latency and sleep maintenance with a shift in circadian rhythms, tasimelteon has the potential for the treatment of patients with transient insomnia associated with circadian rhythm sleep disorders, including people affected by jet lag, or those who work at night, and early-rise workers." Tasimelteon compared to bezodiazepines (and Ambien or Lunesta 8) treatment for sleep disorders (therapies) is not addictive or causes dependency. 4

Dr. Jay Udani, who runs the integrative medicine program at Northridge Hospital Medical Center, said regarding approval usage of Tasimelteon requires: "That needs controlled studies in the field". 8 Further studies will evaluate how Tasimelteon will regulate role of Circadian rhythm sleep disorders for the treatment of other health concerns including depression, non-diper hypertension (condition when the blood pressure does not fall at night. 7) and other conditions. 9 Expected Tasimelteon will be approved for sale within three years. 11

References:

1.) Sleep and Circadian Rhythm Disorders - http://www.webmd.com/sleep-disorders/guide/circadian-rhythm-disorders-cause

2.) Circadian Rhythm Sleep Disorders - http://www.talkaboutsleep.com/circadian-rhythm-disorders/circadian-rhythm-sleep-disorders/07-circadian-rhythm-sleep-disorders.htm

3.) Circadian Rhythm Helpful Information - http://www.soundsleeping.org/articles/circadian-rhythm.htm

4.) Tasimelteon Shown to Help People Sleep Better and Shift The Internal Clock in Jet Lag/ Night Work, The Lancet - http://www.medicalnewstoday.com/articles/131400.php

5.) New medication brings hope of jet lag cure - http://www.eurekalert.org/pub_releases/2008-12/mu-nmb120108.php#

6.) Vanda Pharmaceuticals, Inc, (VNDA) Says Insomnia Drug Trial Meets Goal

6/26/2008 - http://www.biospace.com/news_story.aspx?StoryID=101583&full=1

7.) High blood pressure - http://www.umm.edu/patiented/articles/what_will_confirm_diagnosis_of_high_blood_pressure_000014_2.htm

8.) New drug may put jet lag to rest - http://www.latimes.com/news/science/la-sci-sleep2-2008dec02,0,6502985.story?track=rss

9.) Clinical Trail Results on the Sleep-Promoting Effects of Vanda Pharmaceuticals Circadian Regulator Tasiemelteon (VEC-162) Published in The Lancet - http://biz.yahoo.com/prnews/081201/ph49235.html?.v=1

10.) The Sleep = Wake Cycle - http://www.sleepfoundation.org/site/c.huIXKjM0IxF/b.2421201/k.5FF7/Melatonin__The_Basic_Facts.htm

11.) New drug brings hope for jet lag sufferers - http://www.cnn.com/2008/TRAVEL/12/02/jet.lag.drug/index.html?section=cnn_latest

12.) Jet Lag Sleeplessness Targeted by Vanda's New Pill (Update 2) - http://www.bloomberg.com/apps/news?pid=20601202&sid=aqfILQbRJ0t4