CORRECTED - CORRECTED-UPDATE 1-XenoPort's restless legs drug meets main goal
(Corrects paragraph four to clarify that the lower dose of the drug also showed statistically significant improvements compared with the dummy drug in the latest trial) (Recasts; adds details, share movement)
Feb 28 (Reuters) - Biopharmaceutical company XenoPort Inc (XNPT.O) said its drug to treat restless legs syndrome met the main goals of a third late-stage trial, sending its shares up as much as 6 percent.
XenoPort and co-developer British drugmaker GlaxoSmithKline (GSK.L) (GSK.N) plan to seek approval for marketing the drug, XP13512, in the third quarter. The companies will submit data from all three late-stage trials to U.S. health regulators.
People with restless legs syndrome (RLS) experience sensations in the legs that result in a compelling urge to move, to relieve the discomfort temporarily. Because symptoms typically occur at night, RLS patients often suffer from sleep disruption.
The third late-stage trial studied two doses of XP13512, 1200mg and 600mg. Both doses showed statistically significant improvements compared with a dummy drug.
One of the main goals of the trial was to show improvement in the International Restless Legs Syndrome (IRLS) rating scale score at the end of treatment. The IRLS rating scale is a ten-item scale used to assess the severity of RLS.
The second main goal of the trial was to show significant improvement in the Investigator Clinical Global Impression of Improvement (CGI-I) scale score at end of treatment, a scale used to measure if a patient's illness improved or worsened.
Withdrawals from the trial due to adverse effects like dizziness were 7 percent in the higher-dose group and 6 percent in both the lower-dose and dummy-drug groups.
The adverse effects were generally mild or moderate in intensity, the company said in a statement.
Xenoport shares rose to a high of $ 58.25, before falling back to trade up $2.78 at $57.67 Thursday in early morning trade on Nasdaq.
Shares of GSK were trading down 31 cents at $45.16 on the New York Stock Exchange. (Reporting by Jennifer Robin Raj in Bangalore; Editing by Pratish Narayanan)
