The FDA separates medical devices into three classifications:
- Class I devices carry low risk and are subject to the least regulatory controls (e.g., dental floss).
- Class II devices are higher risk than Class I and require greater regulatory controls to provide reasonable assurance of the device’s safety and effectiveness (e.g., condoms).
- Class III devices are the highest risk and are therefore subject to the highest level of regulatory control. These devices must be approved by the FDA through testing before they are marketed (e.g., replacement heart valves).
Many medical devices produced by companies have similarities to existing devices or improve upon existing medical devices. The 510(k) process allows companies to prove that their new device has substantial equivalence to a legally marketed, previously approved device (a “predicate”.)
A device is substantially equivalent if, in comparison to a predicate, it either:
- Has the same intended use as the predicate and has the same technological characteristics as the predicate; or
- Has the same intended use as the predicate and has different technological characteristics as the predicate, but the supplementary information submitted to FDA:
- Does not raise new questions of safety and effectiveness; and
- Demonstrates that the device is at least as safe and effective as the legally marketed device.
As the FDA points out, a claim of substantial equivalence does not mean the new and predicate devices must be identical. Substantial equivalence is established with respect to intended use, design, energy used or delivered, materials, chemical composition, manufacturing process, performance, safety, effectiveness, labeling, biocompatibility, standards, and other characteristics, as applicable.
De novo classification is a process for medical device approval when there is no substantially equivalent predicate. Medical device manufacturers have two options for de novo classification:
- If the manufacturer submits a 510(k) clearance and receives a “not substantially equivalent” (NSE) determination from FDA, they may request, within 30 days of receiving the determination, that the FDA make a risk-based classification of the device; or,
- If there is no legally marketed device upon which a determination of substantial equivalence can be based, the manufacturer may request the FDA to make a risk based classification under without first submitting the 510(k) clearance.