"FDA has finalized the risk management plan with the manufacturer of Definity and has approved labeling changes that remove most of the contraindications cited in the October, 2007 warnings, as well as monitoring procedures upon patients with pulmonary hypertension or unstable cardiopulmonary conditions.
"FDA is working with the manufacturer of Optison to effect similar changes to the label and to finalize a risk assessment and management program," according to the FDA paper published last month.
"FDA remains concerned about the safety of these products and they continue to contain a boxed warning that highlights the risk for serious cardiopulmonary reactions," the paper concludes.
GE's Dr. Black says that the concern about ultrasound bubbles was an "over-interpretation" of patients who were already sick and should not have had the procedure.
He says that ultrasound bubbles have the fewest side effects of any contrast media, but sometimes give the least information. Other contrast media include iodinations and gadolinium dyes.
Iodinations are used with X-rays and CT scans. These dyes are used to look at coronary vessel blockages with angiograms and also for tumors in body cavities, such as the abdomen. (See https://www.dotmed.com/news/story/6518.)
The gadolinium dyes, considered the most dangerous dyes for patients with kidney disease, are used with MRIs and are most commonly used for tumors or abnormal structures, Dr. Black says.
"If you have a patient with cancer, it may be more important to use a more risky gadolinium or iodine contrast dye and see where the structure is, than to not take any risk at all," he adds. "In other words, just like with the ultrasound bubbles, the benefit of using MRI or CT with contrast media should outweigh the risk of using contrast to the patients. In the vast majority of cases, we clearly think it does."
Dr Black notes, "It was quite a shock to the FDA after Vioxx and other drugs were taken off the market" so the agency is being particularly cautious now.
He says GE is trying to work with the FDA to try to come up with an appropriate warning label.
"Every company wants to do the right thing. Everyone is trying to figure out where the appropriate balance is between risk and benefit. But there's not enough progress being made because everyone is afraid of the regulatory process," Dr. Black says.
He adds, "We're going through a bump now. It seems to many of us that we need more scientific discussion. Concern of the public is just about safety; they don't realize the benefits derived from being able to see the structure and function of organs."