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Ahead of the Bell: Insmed shares sink

The Associated Press

Shares of Insmed slumped Wednesday in premarket trading after its lung disease treatment fell short of its main goal in a mid-stage study.

The inhaled antibiotic Arikayce did not lead to a statistically significant reduction in bacteria density when compared to a fake drug or placebo in the study. A total of 90 patients with a treatment-resistant lung infection received standard-of-care treatment plus either Arikayce or the placebo in the study.

Insmed has no products on the market and is developing inhaled treatments for patients battling rare lung diseases. Arikayce is the company's most advanced treatment. It also is studying the drug as a treatment for an infection found in cystic fibrosis patients.

The company, based in Monmouth Junction, N.J., said it will talk to regulators in both the United States and Europe to determine the next step forward for the drug. The treatment did yield a statistically significant difference in culture conversion, a secondary goal of the study, and Insmed said it would seek a "breakthrough therapy" designation from U.S. regulators based on those results.

Shares of Insmed Inc. fell 7 percent, or $1.28, to $17.02 less than an hour before markets opened Wednesday. That move largely wiped out the stock's gains so far this year, after closing 2013 at $17.