Which statement best differentiates the two US pathways for medical device premarket clearance and approval?

• A. 510(k) is for lower-risk devices; PMA is for high-risk devices.
• B. 510(k) demonstrates substantial equivalence to a predicate device; PMA requires substantial evidence of safety and effectiveness via clinical data.
• C. 510(k) requires no clinical data; PMA requires no data.
• D. 510(k) and PMA are interchangeable.

Answer: (B)

The main idea is how the FDA proves a device can be marketed through two different routes that require different kinds of evidence. The premarket notification path is based on substantial equivalence to a predicate device already on the market. That means the new device has the same intended use and similar technological characteristics as a legally marketed device, so the evidence is typically nonclinical data and performance testing, with any clinical data only as needed to address questions of safety and effectiveness. The emphasis is on showing the new device measures up to an existing one rather than proving its own safety and effectiveness from scratch.

The premarket approval path, by contrast, is about substantial evidence of safety and effectiveness, and that usually comes from clinical data. This route is used for high-risk devices and requires robust clinical studies to demonstrate that the device provides benefits that outweigh risks for its intended use.

So the best statement captures that 510(k) relies on substantial equivalence to a predicate, while PMA requires substantial evidence of safety and effectiveness via clinical data. The other options misstate the roles of clinical data, risk classification, or whether the pathways are interchangeable.