The 1976 Medical Device Amendments granted the US Food and Drug Administration (FDA) regulatory authority over medical devices. The FDA’s regulatory review requirements are intended to correspond to the amount of information needed to provide “reasonable assurance of device safety and effectiveness” and establish a 3-tiered system for classifying devices based on their risk profile (low, moderate, and high) with a corresponding degree of evidence required for review. Low-risk devices are typically only subject to general controls (eg, good manufacturing practices) and exempt from premarket review. Nearly 90% of medical devices that undergo regulatory review are classified as moderate risk and receive authorization through the 510(k) process, which additionally requires manufacturers to demonstrate “substantial equivalence” to a previously authorized (predicate) device, usually without being required to show evidence of device safety and effectiveness from clinical studies. Devices in the third category, high risk, are fewer in number, frequently implanted and/or life-sustaining, and undergo the most rigorous regulatory review through the premarket approval pathway, which requires evidence from clinical studies demonstrating safety and effectiveness.
