An Updated Clinical Trial for Totally Blind Individuals with Sleep Disorders

Graphic of a clock face shrouded in darkness, with the hour hand between 1 AM and 2 AM

Vanda Pharmaceuticals, Inc., a biotechnology company in Rockville, MD, is currently recruiting study participants for a Phase 3 clinical trial of an experimental drug treatment for totally blind individuals with no light perception who experience a sleep problem called “Non-24-Hour Sleep-Wake Disorder.” In the United States, this disorder affects approximately 65,000 totally blind individuals who lack the light sensitivity necessary to reset their internal “body clocks.”

About the Study

Here is the study announcement, along with clinical trial information from the Vanda Pharmaceuticals website:

Individuals who are totally blind with recurring sleeping or napping problems are needed to answer a survey and/or take part in a clinical research study. For each completed survey, $25 will be donated to organizations that support people with blindness.

Eligible persons who take part in the clinical research study will be compensated for their time and will receive all study-related investigational medication, medical evaluation, and transportation at no cost.

Sleep problems and napping occur in some individuals who are totally blind. This may be caused by the lack of light needed to reset the “body clock.” The result is recurrent sleep problems similar to jet lag.

Individuals may qualify who:

  • are between 18 and 75 years of age
  • are totally blind with no light perception
  • have recurrent trouble sleeping at night or experience daytime sleepiness or napping.

For more information, visit the project website at; call 1-888-389-7033 (toll free) Monday-Friday, 9:00 AM to 5:00 PM EST; or send an email to

About Non-24 Hour Sleep-Wake Disorder

You can find additional information about Non-24-Hour Sleep-Wake Disorder, including frequently-asked questions, news, and research updates at the 24SleepWake website.

Tasimelteon is the drug that is being studied in the clinical trial:

Graphic of the chemical composition of Tasimelteon

Tasimelteon is an oral compound in development for sleep and mood disorders, including Circadian Rhythm Sleep Disorders (CRSD). Examples of CRSD include transient disorders such as jet lag and chronic disorders such as shift work sleep disorder and Non-24-Hour Sleep-Wake Disorder.

Tasimelteon has been shown to improve sleep parameters in prior clinical studies that simulated a [disruption] of the circadian clock. In two such studies, tasimelteon caused significant improvement in sleep onset and sleep maintenance without evidence of next-day residual effects.

On January 19, 2010, the FDA granted orphan drug designation status for tasimelteon in Non-24-Hour Sleep-Wake Disorder in blind individuals without light perception.

Orphan Drug Status

Here is more information about orphan drug status and the Orphan Drug Designation program:

The Food and Drug Administration has charged the Office of Orphan Products Development to dedicate its mission to promoting the development of products (drugs, biologics, devices, or medical foods) that demonstrate promise for the diagnosis and/or treatment of rare diseases or conditions.

The Orphan Drug Designation program provides orphan status to drugs and biologics which are defined as those intended for the safe and effective treatment, diagnosis, or prevention of rare diseases/disorders that affect fewer than 200,000 people in the United States, or that affect more than 200,000 persons but not are not expected to recover the costs of developing and marketing a treatment drug.

For more information about the clinical trial and project, visit the project website at; call 1-888-389-7033 (toll free) Monday-Friday, 9:00 AM to 5:00 PM EST; or send an email to


Matilda Ziegler magazine has published an informative five-part series on Non-24-Hour Sleep-Wake Disorder by Lynne Lamberg, a science writer with expertise in the area of circadian rhythm biology. It’s well worth a read!

VisionAware will provide additional updates of this research as they become available.