There Must Be Some Misunderstanding: FDA Issues a Warning Letter to a Medical Device Company That Made the Wrong Decision on Regulatory Classification

Footnotes for this article are available at the end of this page.

In 1980, the British rock band, Genesis, released “Misunderstanding.” Forty-three years later, the Food and Drug Administration and a medical device company fell into a misunderstanding about a product’s regulatory classification and status. The “misunderstanding” resulted in a Warning Letter that caught our eye. It waded into the enforcement area of medical device versus Medical Device Data Systems (“MDDS”) and Clinical Decision Support (“CDS”) Software.1 In this case, FDA found that the product was a medical device, lacked a Premarket Approval Application, and was, therefore, “adulterated.”2 In this Bulletin, we will focus on the MDDS/CDS/medical device discussion in the Warning Letter.3


  • As background, for our purposes, the criteria for a CDS product are:
    • not intended to acquire, process, or analyze a medical image or a signal from an in vitro diagnostic device or a pattern or signal from a signal acquisition system;
    • intended for the purpose of displaying, analyzing, or printing medical information about a patient or other medical information (such as peer-reviewed clinical studies and clinical practice guidelines);
    • intended for the purpose of supporting or providing recommendations to a healthcare professional about prevention, diagnosis, or treatment of a disease or condition; and
    • intended for the purpose of enabling such healthcare professional to independently review the basis for such recommendations that such software presents so that it is not the intent that such healthcare professional rely primarily on any of such recommendations to make a clinical diagnosis or treatment decision regarding an individual patient.
  • If all four criteria are met, the software function may be a Non-Device CDS, excluded from the medical device definition.4
  • Non-Device MDDS are software functions that are solely intended to transfer, store, convert formats, or display medical device data and results.5
  • The product at issue in the Warning Letter was software, which pairs with heart pumps, and encompasses a web-based user portal and a remote link module. It is designed to work with a user control interface that is part of a medical device system, which provides temporary ventricular support to help a patient’s heart to pump blood in a critical care setting.
  • The software allows users to monitor the performance of the heart pumps, view case information on demand, and filter notifications by alarm status.
    • These functions provide patient-specific medical information to detect a life-threatening condition and generate time-critical alarms intended to notify a healthcare provider (“HCP”).
  • FDA contended that the software was a medical device and lacked marketing authorization.
  • In response, the company said that the software was exempt from device regulation.
  • The company claimed that the software provides clinical users with the ability to receive email notifications based on the interface alert trigger data that is streamed to the cloud. The software enables clinicians to view case tile pump metrics, which displays information equivalent to what is communicated on the interface.
  • The company contended that these features were Non-Device CDS functions, because they support an HCP by providing a concise and user-friendly view of active case status and notifications.
  • FDA disagreed and said that, by functioning as a secondary alarm system with color-coded tiles and pre-set thresholds to notify users by email of alarms issued from the interface, the software failed to meet the criteria of Non-Device CDS Software.
  • FDA reiterated that, although some functions of the software may be CDS-related or a MDDS product, the system was a medical device, because the color-coded alarms and email notifications of alarms provide patient-specific medical information to detect a life-threatening condition and display time-critical alarms intended to notify an HCP about the need for potential clinical intervention.

AGG Observations

  • The Warning Letter distinguishes between MDDS/CDS and medical devices. Companies should review their product labeling, promotion, and other product attributes to evaluate a product’s regulatory status. FDA guidance and our previous Bulletin are useful resources.
  • It appears FDA became aware of the issue during an inspection, and not because of any product promotion.
  • A “misunderstanding” of the law or FDA’s expectations may lead to “some kind of mistake” (another lyric in the aforementioned song), a mistake that can be costly and delay product authorization and sales.



[2] 21 U.S.C. § 351(f)(1)(B). The device company was also deficient in many quality-related and other issues, but that is beyond the scope of this Bulletin.

[3] For more information on FDA’s CDS software guidance, please view a previous AGG Bulletin here.