Quoted from http://www.reuters.com/article/marketsNews/idCNN1737499420091117
US FDA sees varying risk from MRI agents
WASHINGTON, Nov 17 (Reuters) - Some contrast agents used with magnetic resonance imaging scans appear to carry a higher risk of a potentially fatal skin disease than others, U.S. drug reviewers said in documents released on Tuesday.
The Food and Drug Administration said a staff review found the highest risk of the skin disease, nephrogenic systemic fibrosis (NSF), was associated with GE Healthcare's Omniscan, Bayer AG's Magnevist and Covidien's Optimark.
The lowest risk was associated with Prohance and Multihance, made by Bracco Diagnostics, the agency said, adding "the data do not appear to rule out an NSF risk for each of the agents."
The agency said the staff review that found variations among the drugs had limitations and it would take the issue to a panel of outside experts that meets in December.
The products, used to help make MRI scans easier to read, have been given to millions of patients. They are members of a family known as gadolinium-based imaging agents. The FDA announced in 2007 it was requiring a strong "black box" warning on all of the drugs to alert physicians that patients with certain kidney and liver conditions were at risk for for NSF.
Staff in the FDA's drug safety unit said the magnitude of the risk "does not compel removal of specific (imaging agents) from the U.S. market" but recommended that the drug labels note the varying levels of risks with each product.
NSF triggers thickening of the skin, organs and other tissues that makes it difficult to move and can lead to broken bones, although the exact cause is unclear. There is no effective treatment.