UPDATE 1-Chelsea says data on hypotension drug positive, shrs up

* Says further data shows significant symptomatic benefit

* Shares rise 36 pct (Adds analyst comment; updates share movement)

By Anand Basu

BANGALORE, Oct 1 (Reuters) - Chelsea Therapeutics' (CHTP.O) shares jumped as much as 36 percent after it said additional analysis from a late-stage trial of its drug Droxidopa, which missed the main goal of the study last week, showed significant symptomatic benefit in treating a neurological disorder.

Chelsea is developing the drug as a treatment for symptomatic neurogenic orthostatic hypotension (NOH) -- a neurological disorder that causes blood pressure to drop when the afflicted person assumes a standing position.

With the exception of vision, the drug showed a marked improvement over the dummy drug for each of the five other symptoms measured by dizziness, weakness, fatigue, concentration, and head/neck pain, Chelsea said in a statement on Thursday.

The company, which plans to report results from a second late-stage trial in the same indication later this quarter, expects the outcome of the trial to be enhanced by the washout period, when it will stop dosing patients for seven days.

In the first late-stage trial, Study 302, all patients received the drug during the initial open label titration phase. Patients who responded to the drug at any of the doses were kept on the treatment for at least seven days.

Following this, half the responder group was put on the drug daily for two weeks, while the rest got a dummy drug.

However, in the second trial, Study 301, there is a washout period before the patients are randomized for one week.

Data from Study 301 shows a rise in average dizziness score to 5.4 from 1.0 following dose titration after a seven-day washout period, suggesting a reduction in the carry-over effect that appeared in Study 302 subsequent to sustained drug treatment, Chelsea said.

"There is a big increase in the dizziness score, which was the primary endpoint that failed in the 302 study, and that's key data that lowers clinical risk for the 301 study," Wedbush Morgan Securities analyst Liana Moussatos said.

Last Thursday, the company said Droxidopa did not show a statistically significant improvement, measured by the mean score of dizziness or light-headedness of Orthostatic Hypotension Symptom Assessment, compared to a dummy drug.

Oppenheimer & Co analyst Brian Abrahams said, "On the previously-reported secondary endpoint of blood pressure improvement, Droxidopa's effects were less robust than placebo."

"The additional analyses do support the idea that Droxidopa improves NOH symptoms, but the lack of correlation to blood pressure improvements is still somewhat mysterious," he added.

The analyst said the U.S Food and Drug Administration would definitely require another positive trial prior to the drug's approval even with a successful 301 study.

Shares of the company, which lost about 75 percent of their market value last week, touched a high of $3.42, making them one of the top percentage gainers on Nasdaq. The shares were trading up 27 percent at $3.20 Thursday afternoon. (Editing by Aradhana Aravindan)