FDA decides to take warning label off ultrasound contrast
The International Contrast Ultrasound Society (ICUS) has applauded the FDA’s decision to modify the U.S. product label for Definity Injectable Suspension, an ultrasound contrast agent.

ICUS filed a Citizen Petition with the FDA in September asking the agency to remove boxed warnings from ultrasound contrast agents, stating that the warnings deter use of a "safe, inexpensive and radiation-free diagnostic imaging tool with potential life-saving benefits for patients."

“The FDA decision should lead to increased use of contrast, better imaging studies, better diagnosis for patients, and saved lives,” Michael Main, MD, treasurer of ICUS and director of the echocardiography laboratory at Saint Luke’s Mid-America Heart Institute in Kansas City, Mo., said in a statement.

Main added that current safety data doesn’t warrant the FDA’s boxed warnings for ultrasound contrast agents, but the change to Definity’s label makes progress in reflecting the risk-benefit profile of the contrast agent.

“Based on all of the recent studies, without exception, we now know that ultrasound contrast agents are extremely safe and may be an excellent low cost alternative to other diagnostic procedures, including nuclear scans that expose patients to ionizing radiation,” said Steven Feinstein, MD, ICUS co-president and cardiologist at Rush University Medical Center in Chicago. “This will spare many patients from the cumulative effects of ionizing radiation that are inherent in certain alternative forms of diagnostic imaging, including SPECT and CT.”

The Definity label change was made after the FDA reviewed a 2010 proposed label change application from Lantheus Medical Imaging, manufacturer of Definity. New product labels means that it no longer requires 30 minutes of monitoring after drug administration. The label also no longer notes that serious cardiopulmonary reactions are uncommon and removes statements saying the safety and efficacy of Definity with exercise stress or pharmacologic stress testing have not been established.

ICUS reiterated that it believes boxed warnings on ultrasound contrast agents are inconsistent with the FDA’s standards for use of boxed warnings given the strong safety profile of such products, and said boxed warnings on ultrasound contrast agents “stand in direct opposition to the FDA’s statutory responsibility to protect the health of the American public.”