	Introduction

Medical device regulation is complex, in part because of the wide variety of items that are categorized as medical devices. The federal agency responsible for regulating medical devices is the Food and Drug Administration (FDA)—an agency within the Department of Health and Human Services (HHS). FDA's Center for Devices and Radiological Health (CDRH) is primarily responsible for medical device premarket review. CDRH activities are funded by congressional appropriations and user fees collected from device manufacturers, which together comprise the program level budget. User fees account for 43% of FDA's total FY2016 program level and 28% of CDRH's FY2016 program level. FDA's authority to collect medical device related user fees, originally authorized in 2002 ( P.L. 107-250 ), has been reauthorized in five-year increments and was reauthorized through FY2017 by the 112 th Congress via Title II of the FDA Safety and Innovation Act (FDASIA, P.L. 112-144 ). Congress has historically been interested in balancing the goals of allowing consumers to have access, as quickly as possible, to new and improved medical devices with preventing devices that are not safe and effective from entering or remaining on the market. Problems related to medical devices can have serious consequences for consumers. Reports by the Government Accountability Office (GAO), the Department of Health and Human Services Office of the Inspector General, and the Institute of Medicine (IOM) have voiced concerns about FDA's device review process. In 2009, 2011, 2013, and 2015 GAO included FDA's oversight of medical products on the GAO list of high-risk areas. FDA classifies devices according to the risk they pose to consumers. There are two main paths that manufacturers can use to bring moderate- and high-risk devices to market with FDA's permission. One path consists of conducting clinical studies, submitting a premarket approval (PMA) application, and requires evidence providing reasonable assurance that the device is safe and effective. The other path is shorter and less costly. It involves submitting a 510(k) notification demonstrating that the device is substantially equivalent to a device already on the market (a predicate device ) that does not require a PMA. The 510(k) process is unique to medical devices and results in FDA clearance . Substantial equivalence is determined by comparing the performance characteristics of a new device with those of a predicate device. Class III devices are those under current law which "cannot be classified as a class I device because insufficient information exists to determine that the application of general controls are sufficient to provide reasonable assurance of the safety and effectiveness of the device," and "cannot be classified as a class II device because insufficient information exists to determine that the special controls ... would provide reasonable assurance of [their] safety and effectiveness," and are "purported or represented to be for a use in supporting or sustaining human life or for a use which is of substantial importance in preventing impairment of human health," or present "a potential unreasonable risk of illness or injury, [are] to be subject ... to premarket approval to provide reasonable assurance of [their] safety and effectiveness." Generally speaking, under the Federal Food, Drug and Cosmetic Act (FFDCA), manufacturers
are prohibited from selling an adulterated product; are prohibited from misbranding a product; must register their facility with FDA and list all of the medical devices that they produce or process; must file the appropriate premarket submission with the agency at least 90 days before introducing a non exempt device onto the market; and must report to FDA any incident that they are aware of that suggests that their device may have caused or contributed to a death or serious injury. The CDRH program level budget in FY2016 is $450 million, including $127 million in user fees. In 2015, 98% of PMAs accepted for filing were approved by FDA. According to FDA data, 85% of 510(k)s accepted for review in 2015 were determined to be substantially equivalent. The Medical Device Review Process:Post-Market Requirements

Once approved or cleared for marketing, manufacturers of medical devices must comply with various regulations on labeling and advertising, manufacturing, and postmarketing surveillance.
Prior to and since the passage of the Medical Device Amendments of 1976, Congress has debated how best to ensure that consumers have access, as quickly as possible, to new and improved medical devices and, at the same time, prevent devices that are not safe and effective from entering or remaining on the market. Medical device regulation is complex, in part, because of the wide variety of items that are categorized as medical devices; examples range from a simple tongue depressor to a life-sustaining heart valve. The regulation of medical devices can affect their cost, quality, and availability in the health care system.
In order to be legally marketed in the United States, many medical devices must be reviewed by the Food and Drug Administration (FDA), the agency responsible for protecting the public health by overseeing medical products. FDA's Center for Devices and Radiological Health (CDRH) is primarily responsible for medical device review. CDRH activities are funded by congressional appropriations and user fees collected from device manufacturers, which together comprise the program level budget. User fees account for 43% of FDA's total FY2016 program level and 28% of CDRH's FY2016 program level. The CDRH program level budget in FY2016 is $450 million, including $127 million in user fees. FDA's authority to collect medical device user fees, originally authorized in 2002 (P.L. 107-250), has been reauthorized in five-year increments and was reauthorized through FY2017 in the FDA Safety and Innovation Act (FDASIA, P.L. 112-144).
Under the Federal Food, Drug, and Cosmetic Act (FFDCA), all medical device manufacturers must register their facilities and list their devices with FDA and follow general controls requirements. FDA classifies devices according to the risk they pose to consumers. The FFDCA requires premarket review for moderate- and high-risk devices. There are two main paths that manufacturers can use to bring such devices to market. One path consists of conducting clinical studies and submitting a premarket approval (PMA) application that includes evidence providing reasonable assurance that the device is safe and effective. The other path involves submitting a 510(k) notification demonstrating that the device is substantially equivalent to a device already on the market (a predicate device) that does not require a PMA. The 510(k) process results in FDA clearance and tends to be much less expensive and less time-consuming than seeking FDA approval via PMA. Substantial equivalence is determined by comparing the performance characteristics of a new device with those of a predicate device. Demonstrating substantial equivalence does not usually require submitting clinical data demonstrating safety and effectiveness. Once its device is approved or cleared for marketing, a manufacturer must comply with regulations on manufacturing, labeling, surveillance, device tracking, and adverse event reporting. In 2015, FDA approved 98% of PMAs accepted for review and 85% of 510(k)s accepted for review were determined to be substantially equivalent.
Problems related to medical devices can have serious consequences for consumers. Defects in medical devices, such as artificial hips and pacemakers, have caused severe patient injuries and deaths. Reports published in 2009 through 2011—by the Government Accountability Office (GAO), the Department of Health and Human Services Office of the Inspector General, and the Institute of Medicine—have voiced concerns about FDA's device review process. In 2009, 2011, 2013, and 2015 FDA's oversight of medical products was included on the GAO list of high-risk areas. In response to these concerns, FDA has conducted internal reviews and has implemented changes, including plans for a new National Evaluation System for health Technology (NEST).