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Vanda Pharmaceuticals rises on sleep drug results

WASHINGTON (AP) -- Shares of Vanda Pharmaceuticals Inc. rose more than 27 percent Tuesday after the company reported positive results for a drug designed to treat a rare sleep disorder that affects blind people.

THE SPARK: Vanda said its study of 84 patients showed that those taking tasimelteon improved sleep time, nap duration and timing of sleep. The study tracked sleeping patterns of patients who were randomly assigned to take the company's drug or a placebo.

THE BIG PICTURE: Tasimelteon is designed to treat a chronic sleep disorder in which patients can't synchronize their bodies with the 24-hour day cycle. As a result, they continually go to bed later and then wake up later. The condition occurs almost exclusively in people who are completely blind. If approved by the Food and Drug Administration, the company's drug would be the first treatment specifically aimed at the disorder, which affects between 65,000 and 95,000 people in the U.S., according to Vanda.

SHARE ACTION: Vanda Pharmaceuticals Inc. rose 90 cents, or 28 percent, to $4.12 in afternoon trading. Over the past year, shares have traded between $2.92 and $5.47.