Acusphere says its imaging agent is different

Shares of Acusphere Inc. rose 11 percent to $1.50 in aftermarket trading today after the Watertown drug developer said its experimental imaging agent is structurally different from similar products that have come under government scrutiny.

Earlier today, the shares plummeted 31 cents, or 18.7 percent, to $1.35 after news reports said the government is seeking new warning labels for certain contrast agents, used to sharpen images of heart scans.

The FDA confirmed it is investigating reports of death and heart problems in patients treated with drugs from Bristol-Myers Squibb and General Electric. The agency asked them to add warnings about the risks to their product labels.

The drugs are delivered via injection prior to an ultrasound of the heart, to improve visibility of the image.

Acusphere is preparing to submit its own contrast agent, Imagify, to the FDA later this year. It said there have been no reported deaths in more than 1,000 patients who were tested with the drug.

Acusphere currently has no products on the market.
(AP)