FDA: Acusphere drug may have ‘risks’

Washington —- Shares of Acusphere plunged Monday after federal regulators raised serious safety concerns about an imaging drug the company has touted as a potential blockbuster product.

Watertown, Mass.-based Acusphere has asked the Food and Drug Administration to approve its AI-700 formula as an injectable drug to improve the clarity of echocardiograms, medical images of the heart.

The FDA said that animal studies of the chemical showed evidence of hypertension, decreased blood pressure and abnormal behavior.

The agency is “concerned that the safety risks associated with the product are inappropriate for the product’s proposed clinical use,” according to documents posted online Monday. Reviewers said the company’s two studies do not clearly show its effectiveness.

In its briefing documents, Acusphere said no deaths or life-threatening side effects were reported among the nearly 2,000 patients tested.

The company also said the drug’s risk are comparable to those of other drugs used in stress testing procedures.

“I think that in the vast majority of patients, AI-700 is well tolerated,” Acusphere Chief Executive Sherri Oberg said in an interview Monday morning. “I think the FDA and other scientists look to animal studies for supportive evidence, but the most important information is what’s found in the human studies.”

While Acusphere has several other drugs in development, it has no products currently on the market.

Acusphere shares plunged 57.3 percent to 32 cents in midday trading after earlier hitting a 52-week low of 26 cents.