To be sold legally in the United States, a medical device must be either cleared or approved by the FDA. Both “FDA-cleared” and “FDA-approved” provide a reassuring and lofty appeal to the casual observer, but the difference in these terms is stark and significant.
FDA-approved medical devices must undergo testing carried out on humans along with meeting stringent standards (note, however, that the manufacturers are tasked with performing their own clinical testing in pursuit of approval). FDA-cleared medical devices, on the other hand, are those that have been determined by the FDA to be substantially similar to another legally sold medical device. The practical effect is huge – with only one class of devices having undergone direct, device-specific testing.
Unlike with FDA-approved devices, no human testing is required for FDA-cleared devices. Instead, companies must submit a 510(k) to the FDA for review.
The 510(k) is a premarket submission made to the FDA to demonstrate that the device to be marketed is at least as safe and effective, in other words, substantially equivalent, to a legally marketed device that is not subject to premarket approval. The 510(k) pathway is a system created by the FDA exempting companies from more thorough device testing as long as they are substantially similar to a product that has come before. The intention of this system was to ensure innovation was not impeded, but it also inadvertently made possible a method allowing devices to be similar to past devices dating from decades before, to the point where the differences could outweigh the similarities. Once a 510(k) submission is approved and the device is FDA-cleared, future 510(k)
submissions can refer to this latest FDA-cleared device; they are not required to refer solely to FDA-approved devices for support. Because 510(k) submissions are not required to make “primary” references to FDA-approved devices, successive layers of FDA-cleared devices will emerge that rely on an ever-lengthening historical chain of FDA-cleared devices. This dilutes the value of 510(k) submissions, much like the way that copying copies of keys over and over compounds minor distortions and ultimately results in a useless key. Translated to medical devices, as the differences between the devices compound in 510(k) submissions over time, we know less and less about the safety and efficacy of medical devices on the market. Today, the majority of medical devices on the market are FDA-cleared, not FDA-approved.
According to the Internal Consortium of Investigative Journalists, over the past ten years there have been upwards of 1.7 million injuries and 80,000 deaths potentially relating to medical devices. Many of the devices involved were FDA-cleared as opposed to FDA-approved, and had not been tested in a clinical trial setting prior to being implanted in patients. A recent example of the potential risks of FDA-cleared medical devices is the 2018 case of DePuy Synthes, a franchise of orthopedic and neurosurgery companies.
DePuy Synthes had developed a hip replacement procedure using a metal ball and socket, which was FDA-cleared as it was deemed to have substantial similarities to six previous devices, and shared traits with devices from as far back as 1975. Despite FDA-clearance, the metal hip devices experienced degradation problems and high failure rates; the resulting damage to patients caused by DePuy’s metal hip devices has resulted in over $3 billion in settlements. These damages, along with complaints by patients, led to the FDA revoking FDA clearance for the devices and forcing the manufacturer to seek FDA approval.
by Kalyan Emerick