Raptor Pharmaceutical Corp said its experimental brain disorder drug slowed the loss of muscle control in patients with Huntington's disease after 18 months of treatment.
Raptor's shares were up 9 percent at $16.24 in premarket trading on Thursday.
The drug slowed the progression of muscle spasms, eye and hand movements and loss of balance compared to a placebo.
The company said seven patients discontinued treatment during the study. Six of them were treated with the drug, codenamed RP103.
Raptor is also testing the drug in a mid-stage study for non-alcoholic fatty liver disease in children.
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