What is a “Not Substantially Equivalent” (NSE) determination?

A “Not Substantially Equivalent” (NSE) determination refers to a conclusion that a device does not meet the standard for substantial equivalence to a predicate device. In the context of regulatory affairs, particularly under the FDA’s 510(k) clearance process, the concept of substantial equivalence is crucial. When a new device is compared to a predicate device, it is assessed on its intended use and technological characteristics. If the agency determines that the new device does not have the same intended use or is not as safe and effective as the predicate, it is classified as NSE.

This determination has significant implications for the regulatory pathway of the device. An NSE classification means that the device cannot be marketed based on the 510(k) process and typically requires a more rigorous review process, such as a premarket approval application (PMA). This outcome emphasizes the importance of demonstrating substantial equivalence to ensure patient safety and efficacy in medical devices.

The other choices do not accurately reflect what an NSE determination entails. For instance, declaring a device superior to its predicate does not necessarily indicate a lack of substantial equivalence; it may instead suggest a different regulatory route. Similarly, stating that all clinical trials have failed or that conclusions are based only on marketing assessments does