Vertex Pharmaceuticals Inc said its experimental drug improved lung function in adults with cystic fibrosis in a mid-stage trial, sending its shares 53 percent higher in after-hours trading Thursday.
The company said the favorable results were seen in patients who took its experimental VX-661 drug in combination with the its already approved treatment for cystic fibrosis, Kalydeco (ivacaftor).
The Phase II study involved 128 people with cystic fibrosis who had two copies of the most common gene mutation responsible for the debilitating condition in which the lungs are unable to flush out salt and therefore become flooded with mucous and can become easily infected.
Vertex said the drug was generally well tolerated when used alone and in combination with Kalydeco.
Vertex shares were up 53 percent at $81 in after-hours trading from their closing of $52.87 Thursday on the Nasdaq.
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