Amzar File

FDA approves first imaging agent to enhance scans of blood flow

WASHINGTON, Dec. 24 -- The U.S. Food and Drug Administration on Wednesday approved Vasovist Injection, the first contrast imaging agent for use in patients undergoing magnetic resonance angiography, or MRA, a minimally invasive test for examining blood vessels.

Although MRA can be performed without the use of a contrast imaging agent, Vasovist provides a clearer image in patients who are suspected of having blockages or other problems with the blood vessels in their abdomen or limbs. The MRA is performed using magnetic resonance imaging (MRI), which relies on magnetic fields to create highly detailed images of the inside the body.


"This MRA contrast imaging agent provides clinicians with a much clearer scan of blood vessels, compared to MRA without contrast, even in vessels that are difficult to scan because they twist and turn in the body," said John Jenkins, the FDA official in charge of new drugs.

When blood vessels are scanned using MRA without any contrast, radiologists are unable to interpret the images about 10 percent to 30 percent of the time. As a result, radiologists have typically used X-rays to detect blood vessel abnormalities. But this is a lengthy procedure and requires sticking a needle into an artery to inject the X-ray dye, a procedure that may result in injury to vessel walls, blood clots, allergic reactions and potential kidney damage. Vasovist is injected into a peripheral vein and no artery is punctured, thus the potential risks are fewer.

Vasovist is manufactured by a Massachusetts pharmaceuticals company. The active substance in Vasovist is gadolinium, a rare earth metal element that is detected by MRI scanners. When injected, gadolinium interacts with water molecules in the body, giving a stronger signal and, in turn, a better picture.