Anthera Shares Plunge on Stopping Heart Trial for Lack of Effectiveness

Anthera Pharmaceuticals Inc. (ANTH) plummeted 45 percent after canceling a late-stage trial of an experimental treatment for heart disease because it didn’t work.

Anthera declined to $3.56 at the close of trading, for the biggest single-day drop since the Hayward, California-based company first sold shares to the public in March 2010.

Anthera closed enrollment in the study and told investigators to immediately remove patients from the therapy, varespladib, the company said in a statement on March 9. The treatment was being used with cholesterol-lowering drugs to prevent a recurrence in patients who had suffered from acute coronary syndrome, Anthera said on its website. Varespladib was in the third and final stage of clinical testing generally needed for regulatory approval.

“This new information was totally unexpected and disappointing given the potential benefits of this drug,” Stephen Nicholls, chairman of the executive committee overseeing the trial, said in the statement.

Acute coronary syndrome is an umbrella term that covers a range of medical issues involving blood blocked from the heart, such as heart attack, according to the American Heart Association.

With varespladib’s failure, the company’s lead drug is now blisibimod, a therapy for systemic lupus in the second stage of testing that will face a challenging market, Steve Scala, an analyst at Cowen & Co. in Boston said today in a note to clients.

“A poorly defined lupus market and disappointing sales of novel agents in this space further temper our enthusiasm,” he wrote.

To contact the reporter on this story: Ryan Flinn in San Francisco at rflinn@bloomberg.net

To contact the editor responsible for this story: Reg Gale at rgale5@bloomberg.net

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