Q: At what point in the development process should sponsors start considering device classification?
A: Class I devices: From a risk-based standpoint, this class is expected to have the least amount of risk to patient safety. These devices are subject to general controls. General controls are the basic provisions required to ensure the device is safe and effective. Most of the devices in this class are considered 510(k) exempt. However, there are Class I devices on the Reserved Devices list that are not exempt and require a 510(k). Examples of these are blood bank supplies and dental hand pieces & accessories.
Class II devices: These devices are determined by the FDA to provide a higher risk than Class I devices and require special controls in addition to the general controls. The more stringent regulatory controls are intended to provide additional assurance of their effectiveness and safety. The additional controls may include special labeling requirements, mandatory performance standards, and post-market surveillance. Examples of Class II devices include surgical drapes, anesthesia conduction kits, and arthroscope. Class II devices are not exempt from GMP requirements. There are some Class II devices that are 510(k) exempt. Class I and II exempt devices are defined in the Code of Federal Regulation and can be found in 21 CFR Parts 862-892. Examples of Class II devices that are 510(k) exempt are catheter guide wires, trocars, and stethoscopes.
Class III devices requiring premarket approval (PMA): When devices are used to support or sustain human life, prevent the impairment of human health, or present a potential, unreasonable risk of illness or injury, they often receive Class III designation. These products carry the highest risk to practitioners and patients, and require general controls and Premarket Approval (PMA). Class III devices require a PMA unless they were on the market prior to 1976 or they are substantially equivalent to a device on the market prior to 1976. Class III devices that meet either of these two criteria require the submission of a 510(k). Examples of Class III devices requiring a PMA include aortic stent, intraocular lens, and pacemaker batteries.