Industry appeals to FDA to maintain current guidelines for heart imaging agents
The current guidelines require companies to prove anatomical benefits before approval, said Dwaine Rieves, MD, director of the FDA’s division of medical imaging. Rieves told the panel that the agency wanted advice on what safety concerns to consider as companies seek expanded indications for the agents.
Several companies, including Acusphere of Watertown, Mass., are currently seeking FDA approval for ultrasound heart imaging agents.
An FDA panel composed of outside medical experts discussed contrast agents, including how the agency should assess the drugs' safety. The panel did not vote on any regulatory action. The panel was charged with discussing the risks of two currently FDA-approved agents, GE Healthcare’s Optison and Lantheus Medical Imaging’s Definity.
Definity and Optison came under increased scrutiny last year after post-marketing reports associated the drugs with hundreds of adverse events. In October 2007, the agency added a black-box warning on ultrasound contrast agents, after receiving about 200 reports of serious allergic reactions, seven of which resulted in death.
Panel members agreed that “psuedo-complications” prompted the deaths and other adverse events, but questioned the drugs’ effectiveness in saving patients’ lives, prompting some to suggest that the FDA change the pre-approval guidelines.
Since October, the FDA has approved labeling changes for Definity that remove most of the warnings added in October, and the agency is working with GE to make similar changes for Optison. However, the drugs still carry black-box warnings.
“There is a strong sentiment on the committee that some outcome is needed to drive decisions on whether these drugs are effective," said panel chairman William R. Hiatt, president of the Colorado Prevention Center in Denver.
While the agency is awaiting the clinical results from randomized controlled trials, the panel also suggested that observational studies could provide needed insight.