Alexion Pharmaceuticals (ALXN - Get Report) shares were taking a pounding after the company's heart drug failed to meet the main target of a study in which it was aiming to prevent heart attacks in a moderate- to high-risk group of patients.
Lately, the shares were plunging $8.19, or 27.7%, to $21.37. Volume was extremely heavy, with 20 times more shares trading than the daily average for the last three months. By midsession, more than 10 million shares had changed hands, compared with about 458,000 on a normal day.
The trial of Alexion's pexelizumab was designed to determine whether the drug could reduce the rate of heart attacks and death 30 days after coronary artery bypass surgery, with or without another valve surgery, compared with a placebo. The drug did reduce both outcomes, but fell short of the threshold for statistical significance.
The trial, which was also conducted to study the drug's safety, involved 4,250 patients at 250 sites worldwide."We are clearly disappointed that pexelizumab did not meet its primary endpoint in