During the US Food and Drug Administration’s two-day public workshop on its Mobile Medical Applications Draft Guidance held September 12 and 13, 2011, attendees and FDA officials wrestled with the issue of how to classify applications that serve as accessories to medical devices.

FDA policy advisor Bakul Patel and Bryan Benesch, determination officer at the Center for Devices and Radiological Health’s (CDRH) office of compliance, reiterated the agency’s general purpose approach that an accessory’s classification typically aligns with that of its associated device during a panel discussion on connecting accessories to devices. However, Benesch and other panelists acknowledged that the issue of apps connecting to multiple devices with different classifications—not covered by the FDA mobile app guidance—does not fit neatly within that approach. Given how varied accessory-device configurations can be, regulators will require a much more nuanced approach in this area, but the details of such an approach need hashing out.

Bradley Thompson, attorney at law firm EpsteinBeckerGreen, suggested intended use statements from the manufacturer or developer of an accessory—what the manufacturer is saying about the app and how the app is being marketed—as one criterion to be taken into account in order to determine the proper level of regulation. Furthermore, the FDA should focus on classifying accessory apps based on their functionality rather than their technology, Thompson argued, in order to avoid overregulation.

Jorge Valdes, chief technology officer at glucose sensor product developer Dexcom, made a point of distinguishing between apps that simply move data between sources or devices and those that actually analyze that data. FDA regulators should focus on where in the process analysis of medical data is occurring, according to Valdes. Apps and devices only providing displays of data should be kept on a low-risk, low-regulatory pathway while still complying with quality system requirements.

Expected treatment outcomes should also factor into how the FDA regulates medical device accessories, argued Marc Anderson of the Juvenile Diabetes Research Foundation. Particularly in challenging cases involving apps and accessories connect to multiple devices, he said, focusing on the intended or expected outcomes for patients treated via those configured systems should figure significantly in how those systems are classified.

Following the panel discussion, the FDA appears hardly closer to forming a viable regulatory process for apps as accessories to medical devices. The agency is accepting comments on all aspects of its proposed approach to regulating medical apps until October 19^th—enough time, perhaps, to get a firmer grip on how to deal with the accessories-to-medical-devices issue.