Two FDA Doctors Said Omniscan Worse Than Other MRI Contrast Agents

Pittsburgh, PAMRI contrast side effects and MRI health risks could prove to be a problem for multinational General Electric (GE), according to the October 26 issue of Business Week. GE makes Omniscan, a contrast agent that contains gadolinium.

Omniscan is one of a handful of contrast agents that have come under scrutiny by the US Food and Drug Administration (FDA) with regard to nephrogenic systemic fibrosis (NSF) in patients with weakened or diseased kidneys. At present there have been more than 400 lawsuits filed in US federal courts against GE, Bayer and two other manufacturers.

GE maintains there is no proof that Omniscan causes the disease. In a position paper released back in February, GE stated, "NSF is a complex disease with a number of contributing factors."

It should be noted that the FDA has put all of the allegedly problematic contrast agents into one category for the purpose of the issuance of a black box warning in May 2007. It has been reported that GE had urged the FDA to treat all agents with equal concern.

However Business Week revealed this month that two of the FDA's own staff doctors determined that Omniscan carries a greater risk than the others. In 2007 Dr. Melanie Blank concluded that an "undeniable and strong association" existed between contrast agents containing gadolinium and NSF, finding that medical and sales data indicated Omniscan "had most of the cases and less of a share of the market, so I believed Omniscan was the worst player."

Following his own, separate review of Omniscan Dr. Louis Marzella said, "a contraindication for Omniscan is warranted" for patients with severe kidney disease.

The FDA subsequently ordered a black box warning for all contrast agents containing gadolinium with respect to the potential for NSF in patients with compromised kidneys and listed Omniscan as the drug most often associated with NSF. However the agency did not contraindicate the drugs for any patient.

A leading imaging-safety expert now says the agency's decision to lump all contrast agents together is "inappropriate and indefensible," according to Dr. Emanuel Kanal of the University of Pittsburgh Medical Center.

Gadolinium is routinely used during MRI scans. While toxic to the human body, gadolinium is expelled by the kidneys before the drug can have any harmful effect. However patients with compromised kidneys risk that gadolinium remains in the body for longer periods. Screening out those with kidney issues appears to mitigate the risk for NSF. However, it has proven too late for some…

GE Healthcare generated a profit of $2.85 billion from sales of $17.4 billion last year, according to Business Week. Omniscan was not broken out in the report.