Wednesday’s hearing of the FDA’s Radiological Devices Advisory panel highlighted the fact that though FDA cannot legally mandate studies of off-label uses for PMA approvals of devices, it has ways of forcing applicants to do such studies all the same.

In this case, the sponsor of a computer-aided detection (CAD) program may be required to design a study that would evaluate its software for use in both concurrent and sequential readings even though the label doesn’t indicate the concurrent method. Concurrent readings are those in which a radiologist looks at the unprocessed images alongside the CAD-processed images while sequential reading is a process in which a radiologist carefully looks over the raw images before examining the CAD-processed images.

Pat Milbank, a regulatory consultant at the meeting to discuss FDA’s requirements, told Medical Device Daily that sequential reading “is the standard use and has been since the first PMAs were approved in CAD.”

This is so even though the agency does not have “the [legal] authority to require studies for off-label use” as defined by the Medical Device Amendments of 1976.

Milbank said that panel members are aware of this legal roadblock, but they “would like to see these off-label studies” all the same.

“My opinion is that the vast majority of radiologists will use the product as labeled,” Milbank said, but academe is curious as to the results from concurrent use, in part because of recent articles suggesting that some radiologists are viewing CAD-processed imaging concurrently with the raw images in an effort to shave some radiology lab time.

Milbank said a lawsuit isn’t the most cost-effective approach for industry on this issue. “The most productive approach is to work with FDA,” she said, because “any legal proceeding would [probably] require more time and more expense” than complying with agency requirements.

Daniel Troy, former chief counsel at FDA and now a partner at the law practice of Sidley Austin (Washington), told MDD that the difference between sequential and concurrent reading may be too fine a hair to expect the statute to have covered. “This may be a close call” where the language of the law is concerned, but that “FDA nonetheless has some discretion to ask for studies it’s not entitled to.”

“The practical matter is that your remedies are limited” because of the time and money that lawsuits typically devour, Troy said. The agency’s practice of requiring off-label studies is “becoming increasingly common, given the current environment and the fact that FDA appears to be constantly under attack” from a number of quarters, including Congress.

— MARK McCARTY