DESIGN AND DEVELOPMENT OF MEDICAL ELECTRONIC ...

PATH THROUGH THE FDA 443intended use is to cut tissue. A subset of intended use arises when a more specialized indicationis added in the device’s labeling, such as “for making incisions in the cornea.”Class I devices are those for which the FDA requires the lowest level of regulatory control.This classification is given to devices for which there is sufficient information to concludethat safety and effectiveness can be ensured by “general controls” alone. Generalcontrols give FDA authority to enforce against misbranding and adulteration. In addition,the FDA requires manufacturers to register and list their devices, notify consumers ofproblems associated with devices, and follow good manufacturing practices (GMPs) intheir manufacturing operations.Class II devices are those for which the FDA does not believe that general controlssuffice, but for which there is sufficient information that the FDA can establish special controlsto ensure their safety and effectiveness. As such, class II devices are not only subjectto general controls but are also subject to compliance with specific standards, guidelines,and patient or special follow-up once in the market.Class III devices are those for which the FDA requires the strictest regulatory control.This class is reserved for devices for which general and special controls cannot providereasonable assurance of safety and effectiveness or those for which there is insufficientinformation to make that assessment. Typically, a class III device is “represented to be fora use in supporting or sustaining human life or for a use which is of substantial importancein preventing impairment of human health, or presents a potential unreasonable risk of illnessor injury.”PATH THROUGH THE FDAThe requirements for medical devices to be used in human patients vary according to theregulatory classification of the device. Regardless of classification, all medical devicesneed to be cleared by the FDA before commercial distribution. Most devices are clearedfor marketing either through approval of a premarket approval (PMA) application orthrough clearance of a premarket notification submission on the basis of section 510(k) ofthe FD&C Act.Class I and class II devices are often subject to section 510(k) of the act, which is usedto determine whether a new device is substantially equivalent to a device in use prior toMay 28, 1976 (a preamendment device), or should be classified as a postamendmentsdevice. Substantial equivalence is based on the device’s intended use, its technical characteristics,as well as safety and effectiveness aspects. A manufacturer submitting a 510(k)application must supply information identifying a medical device that was marketedlegally prior to the amendment. If the device is found to be substantially equivalent, it canbe marketed immediately, whereas a new device that is not substantially equivalentrequires to go through the PMA process. The advantage of the 510(k) route is that it is substantiallyfaster and less costly than the PMA application.Preparing a PMA application is definitely not a trivial pursuit. A PMA application mustinclude:• Full reports of all information known to the manufacturer (regardless of whether it isgood or bad) concerning all research done to demonstrate safety and effectiveness• Detailed description of all components, properties, and principles of operation of thedevice• Detailed manufacturing data• Proposed labeling (which includes any text or informational figures on the device,packaging, and literature)