FDA Regulation of Medical Devices

FDA Regulation of Medical Devices
January 4, 2023
Medical devices are an important part of health care service delivery, and developments in new
technologies can improve their ability to diagnose and treat illness. The medical device industry
Amanda K. Sarata
produces a wide range of products—from bandages to ventilators to pacemakers—that pose
Specialist in Health Policy
varying amounts of risk to the consumer. Given the range of products available and the potential

risks associated with them, the regulation of medical devices is complex and differs from
regulation of other medical products (e.g., drugs).

The Food and Drug Administration (FDA), an agency within the Department of Health and Human Services (HHS), is
responsible for regulating the safety and effectiveness of medical devices. FDA’s Center for Devices and Radiological Health
(CDRH) is primarily responsible for medical device regulation, with assistance from the Center for Biologics Evaluation and
Research (CBER). Medical device manufacturers are subject to a range of regulatory controls (i.e., requirements) to ensure
that devices are not adulterated or misbranded and to otherwise assure their safety and effectiveness for their intended use.
These requirements include, for example, premarket review, labeling, establishment registration and device listing, and
quality system regulation (good manufacturing practices for devices).
This report describes (1) FDA’s authority to regulate medical devices; (2) medical device classification panels and regulatory
classes; (3) device regulatory controls, including general and special controls, as well as premarket approval; (4) special
programs to improve access to specific devices; and (5) postmarket surveillance systems. This report is intended to provide a
broad overview of FDA medical device regulation, and as such, it may not describe every applicable device requirement.
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Contents
Introduction ..................................................................................................................................... 1
FDA’s Authority to Regulate Medical Devices ............................................................................... 1
Medical Device Classification Panels and Regulatory Classes ....................................................... 2
Classification Panels ................................................................................................................. 2
Regulatory Classes .................................................................................................................... 3
Reclassification ................................................................................................................... 4
Medical Device Regulatory Controls .............................................................................................. 6
General Controls ....................................................................................................................... 6
Establishment Registration ................................................................................................. 6
Device Listing ..................................................................................................................... 7
Premarket Notification (510(k)) ......................................................................................... 8
Current Good Manufacturing Practices (Quality System Regulation) ............................. 12
Adulterated and Misbranded Devices ............................................................................... 13
Records and Medical Device Reporting ........................................................................... 15
Banned Devices ................................................................................................................ 16
Notification and Recall ..................................................................................................... 17
Labeling ............................................................................................................................ 18
Special Controls ...................................................................................................................... 20
Premarket Approval (PMA) .................................................................................................... 20

PMA Amendments and Supplements ................................................................................ 22
Investigational Device Exemption (IDE) .......................................................................... 24
Facilitating Access to Medical Devices ......................................................................................... 25
Humanitarian Device Exemption ............................................................................................ 25
Breakthrough Device Designation .......................................................................................... 26
Postmarket Surveillance ................................................................................................................ 26
Mandatory Postmarket Studies ............................................................................................... 27
522 Studies ........................................................................................................................ 28
Post-Approval Studies ...................................................................................................... 29
Adverse Event Reporting ........................................................................................................ 30
National Evaluation System for Health Technology (NEST) and Real-World
Evidence (RWE) .................................................................................................................. 31

Figures
Figure 1. The 510(k) Third Party Review Program Process.......................................................... 12

Tables
Table 1. Medical Device Classification ........................................................................................... 4
Table 2. Types of PMA Supplements ............................................................................................ 23

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Appendixes
Appendix A. History of Laws Governing Medical Device Regulation ......................................... 34
Appendix B. Acronyms Used in This Report ................................................................................ 40

Contacts
Author Information ........................................................................................................................ 41


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FDA Regulation of Medical Devices

Introduction
Medical devices are an important part of health care service delivery and developments in new
technologies can improve their ability to diagnose and treat illness. The medical device industry
produces a wide range of products—from bandages to ventilators to pacemakers—that pose
varying amounts of risk to the consumer. The FDA regulates more than 190,000 distinct devices.1
Given the large number of devices, and the potential risks associated with them, the regulation of
medical devices is complex and differs from regulation of other medical products (e.g., drugs).
The Food and Drug Administration (FDA), an agency within the Department of Health and
Human Services (HHS), is responsible for regulating the safety and effectiveness of medical
devices. FDA’s Center for Devices and Radiological Health (CDRH), established in 1982, is
primarily responsible for medical device regulation. Medical device manufacturers—and, in some
cases, user facilities, device labelers, and importers—are subject to a number of requirements to
ensure that devices are not adulterated or misbranded and to otherwise assure their safety and
effectiveness. These requirements include, for example, device tracking and reports of removals
and corrections.
Congress has historically been interested in allowing consumers to have access, as quickly as
possible, to new and improved medical devices while at the same time preventing unsafe and
ineffective devices from entering or remaining on the market. These contrasting goals may exert
opposite pulls, with implications for consumers, the health care system, and the economy.
Manufacturers decide to develop new devices based in part on the cost of doing so. Additional
regulatory requirements may escalate these costs, while other incentives, such as tax breaks, may
diminish them. If a device development cost is too high, that device or product may be not
developed or brought to market, and consumers are denied access to its potential benefits. This
lack of access has led to proposals for, and the enactment of, incentives to develop medical
devices for rare diseases and pediatric populations. However, if the regulation and oversight of
device development are not adequate, unsafe or ineffective products may reach the market and
harm consumers.
This report describes (1) FDA’s authority to regulate medical devices; (2) medical device
classification and regulatory controls, including premarket review requirements; (3) postmarket
surveillance systems; and (4) compliance and enforcement. This report is intended to provide a
broad overview of FDA medical device regulation, and as such, it may not describe every
applicable device requirement.
FDA’s Authority to Regulate Medical Devices
Under its authorities in the Federal Food, Drug, and Cosmetic Act (FFDCA), FDA regulates the
safety and effectiveness of medical devices, which are a type of medical product. A medical
device (or “device”) is defined in the FFDCA as “an instrument, apparatus, implement, machine,
contrivance, implant, in vitro reagent, or other similar or related article, including any component,
part, or accessory, which is ... intended for use in the diagnosis of disease or other conditions, or

1 FDA, “Statement from FDA Commissioner Scott Gottlieb, M.D. and Jeff Shuren, M.D., Director of the Center for
Devices and Radiological Health, on transformative new steps to modernize FDA’s 510(k) program to advance the
review of the safety and effectiveness of medical devices,” November 26, 2018, https://www.fda.gov/news-events/
press-announcements/statement-fda-commissioner-scott-gottlieb-md-and-jeff-shuren-md-director-center-devices-and.
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in the cure, mitigation, treatment, or prevention of disease, in man or other animals.”2 All FDA-
regulated medical products conceptually meet the definition of a drug as defined in the FFDCA.3
However, unlike a drug, a device “does not achieve its primary purpose through chemical action
within or on the body ... and is not dependent on being metabolized for the achievement of its
primary intended purposes.”4 Certain products are considered combination products—therapeutic
or diagnostic products that combine drugs and devices—and may be assigned to FDA’s CDRH,
Center for Drug Evaluation and Research (CDER), or to the Center for Biologics Evaluation and
Research (CBER), depending on the primary mode of action, among other factors.5
Medical devices are regulated based on the risk posed to the consumer. All devices are subject to
general controls (e.g., registration and listing), which are intended to ensure that the devices are
safe and effective once marketed. Certain devices, because of the risk they pose to consumers,
must undergo FDA premarket review to determine whether they provide reasonable assurance of
safety and effectiveness prior to marketing. Additionally, some devices are subject to special
controls
—for example, requirements for special labelling or postmarket studies.
FDA can take corrective action against a device manufacturer, importer, distributor, or other
registrant if the agency finds that such registrant is in violation of FFDCA requirements or FDA
regulations. Such corrective actions include warning letters, seizures, injunctions, and criminal
prosecution (with the Department of Justice).6
Medical Device Classification Panels and
Regulatory Classes
Medical devices are classified both by medical specialty (i.e., classification panels) and by the
risk posed to the consumer (i.e., regulatory classes). A manufacturer unsure of the classification
panel and regulatory class in which its device belongs may submit to FDA a formal request for
clarification.7
Classification Panels
FDA has developed classifications for over 1,700 generic device types—groups of devices that do
not have differing features regarding safety and effectiveness and require similar regulatory
controls8—and grouped them into 16 medical specialties (e.g., cardiovascular, orthopedic).9 These

2 FFDCA §201(h); 21 U.S.C. §321(h). Pursuant to FFDCA §520(o) (21 U.S.C. §360j(o)), as amended by the 21st
Century Cures Act (Cures Act; P.L. 114-255), certain categories of software functions are excluded from the definition
of a device (e.g., certain types of clinical support software and health administrative software).
3 FDA, Guidance for Industry and FDA Staff: Classification of Products as Drugs and Devices & Additional Product
Classification Issues, September 2017, p. 5, https://www.fda.gov/media/80384/download.
4 FFDCA §201(h); 21 U.S.C. §321(h).
5 FFDCA §503(g)(1); 21 U.S.C. §353(g)(1).
6 For more information, see CRS Report R43609, Enforcement of the Food, Drug, and Cosmetic Act: Select Legal
Issues
, by Jennifer A. Staman.
7 FFDCA §513(g); 21 U.S.C. §360c(g). See also FDA, Guidance for Industry and Food and Drug Administration Staff:
FDA and Industry Procedures for Section 513(g) Requests for Information under the Federal Food, Drug, and
Cosmetic Act
, December 2019, https://www.fda.gov/media/78456/download.
8 21 C.F.R. §860.3(i).
9 FDA, “Classify Your Medical Device,” current as of February 7, 2020, https://www.fda.gov/medical-devices/
overview-device-regulation/classify-your-medical-device.
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16 medical specialties are referred to as classification panels, which are listed in Title 21 of the
Code of Federal Regulations (C.F.R.).10 For each generic device type listed in a respective
classification regulation within a broader classification panel, the C.F.R. gives a general
description of the intended use of the device, information about the marketing requirements, and
the regulatory class (i.e., class I, class II, or class III) in which the device belongs. Device
manufacturers may try to locate the type of device they are intending to market by looking
through the classification panels and associated classification regulations for more information on
likely regulatory controls for their specific device. This process in part supports the regulatory
framework the FDA uses for some devices, specifically those subject to 510(k) notification,
which is based on determinations of substantial equivalence with a predicate device (discussed
below in the “Premarket Notification (510(k))” section.
Genetic Health Risk (GHR) tests, a type of genetic test pioneered by 23andMe, exemplify the
device classification process. Specifically, GHR tests are “intended to provide information on an
individual’s genetic risk for certain medical diseases or conditions.”11 Generally, consumers can
use the results from these tests in discussions with health care providers, or to help guide lifestyle
choices. The GHR test classification panel is “Immunology,” and the generic device type is
“Genetic health risk assessment system.”12 The classification regulation (21 C.F.R. §866.5950)
classifies these devices as class II, as exempt from 510(k) notification in certain cases, and
includes extensive labelling special controls. An example of a specific GHR test within the
generic device type is 23andMe’s Personal Genome Service (PGS) Genetic Health Risk Test for
Hereditary Thrombophilia.13
Regulatory Classes
As established by the Medical Device Amendments (MDA) of 1976 (P.L. 94-295), medical
devices are classified and regulated based on risk posed to the consumer. Each regulatory class
comprises different regulatory controls (i.e., general controls, special controls, and premarket
approval [PMA]), which is described below (see the “Medical Device Regulatory Controls”
section).
Class I medical devices are considered low risk. As such, general controls are considered
sufficient to provide reasonable assurance of safety and effectiveness.14
Class II medical devices are considered moderate risk; therefore, general and special controls are
considered to provide reasonable assurance of safety and effectiveness.15
Class III medical devices are considered high risk; therefore, they are subject to general controls
and the PMA process to provide reasonable assurance of safety and effectiveness.16

10 These panels are found in Parts 862 through 892 in Title 21 of the C.F.R.
11 FDA, “Direct-to-Consumer Tests,” https://www.fda.gov/medical-devices/in-vitro-diagnostics/direct-consumer-tests.
12 21 C.F.R. §866.5950.
13 See FDA, “Device Classification Under Section 513(f)(2)(De Novo),” https://www.accessdata.fda.gov/scripts/cdrh/
cfdocs/cfpmn/denovo.cfm?ID=DEN160026.
14 FFDCA §513(a)(1)(A); 21 U.S.C. §360c(a)(1)(A).
15 FFDCA §513(a)(1)(B); 21 U.S.C. §360c(a)(1)(B).
16 FFDCA §513(a)(1)(C); 21 U.S.C. §360c(a)(1)(C).
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Table 1. Medical Device Classification
Regulatory Class and Classification Panel
Generic Device Type
Regulatory Class
Example
Classification Panel
(Level of Risk)
Regulatory Controls
(Title 21 of the C.F.R.)
(Title 21 of the C.F.R.)
Class I
General Controls
Elastic Bandage
General Hospital
(Low)
(21 C.F.R. §880.5075)
(21 C.F.R. Part 880)
Class II
General and Special
Stethoscope
Cardiovascular
(Moderate)
Controls
(21 C.F.R. §870.1875)
(21 C.F.R. Part 870)
Class III
General Controls and PMA Silicone gel-fil ed breast
General and Plastic Surgery
(High)
prosthesis
Devices
(21 C.F.R. §878.3540)
(21 C.F.R. Part 878)
Source: Created by CRS.
Notes: C.F.R. = Code of Federal Regulations; PMA = Premarket Approval.
Reclassification
As information about a particular medical device changes, it may be subject to reclassification.
Two reclassification processes can be used to change a medical device’s regulatory class (i.e.,
class I, class II, and class III), as outlined in the FFDCA.
Reclassification Request (FFDCA §513(e))
Upon receipt of new information regarding a device type, FDA may initiate or respond to a
petition for reclassification.17 Through an administrative order process,18 FDA may reclassify a
device from any regulatory class to another class (e.g., class III to class II, class I to class III).
Before finalizing the administrative order, FDA is required to (1) publish a proposed order in the
Federal Register that includes the proposed reclassification and a summary of evidence
supporting the proposal, (2) hold a device classification panel meeting, and (3) take into account
comments received through the applicable public docket.19
De Novo Classification Request
Any devices that were not on the market before the passage of the MDA—known as
postamendments devices—are automatically placed in class III, regardless of the risk they pose to
consumers (unless the device is substantially equivalent to one within a preamendments device
type, or to a type that has since been classified as class I or class II).20 The De Novo pathway—
first established in 1997 by the FDA Modernization Act (FDAMA, P.L. 105-115) and amended in
2012 by the FDA Safety and Innovation Act (FDASIA, P.L. 112-144)—allows certain devices
automatically classified, by statute, as class III devices to be reclassified.21 Specifically, through
this pathway, FDA can reclassify a novel low- to moderate-risk device as class I or II from its

17 FFDCA §513(e); 21 U.S.C. §360c(e). See also FDA, “Reclassification,” https://www.fda.gov/about-fda/cdrh-
transparency/reclassification.
18 Prior to the Food and Drug Administration Safety and Innovation Act (FDASIA; P.L. 112-144), this reclassification
process was administered through rulemaking.
19 FFDCA §513(e)(1)(A)(i); 21 U.S.C. §360c(e)(1)(A)(i).
20 FFDCA §513(f)(1); 21 U.S.C. §360c(f)(1).
21 FFDCA §513(f)(2); 21 U.S.C. §360c(f)(2).
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statutorily mandated class III status. A device granted de novo classification creates a new device
type and may serve as a predicate device for new devices of the same type going forward.
Within this pathway, manufacturers have two options when submitting a De Novo reclassification
request. Under the first option, a manufacturer submits a De Novo request after receiving a not
substantially equivalent (NSE) determination in response to a 510(k) submission. Because this
option was deemed burdensome
and time intensive, FDASIA (P.L.
Digital Health and the De Novo Pathway
112-144) created a second option
The De Novo pathway is relatively new compared with other
that allows FDA to classify certain
premarket pathways for devices, but it has played a role in helping
novel devices without first issuing
to review novel types of medical devices, specifically Software as a
an NSE determination after
Medical Device (SaMD) and new types of in vitro diagnostics,
particularly new genomic tests and technologies. For newer classes
reviewing a 510(k) submission.
of medical device technologies that are iterative and/or adaptive—in
particular in vitro diagnostics (IVDs) and software—the De Novo
Under this second option, a
pathway provides a premarket review pathway where no predicate
manufacturer submits a request for
devices exist. The FDA introduced in 2017 and developed and
initial classification of a device,
began piloting the Software Precertification (Pre-Cert) Program in
January 2019, and the De Novo pathway was the regulatory
noting that no legally marketed
pathway used for devices included in this pilot program. FDA
device can be relied upon for a
announced the completion of the Pre-Cert pilot in September 2022,
substantial equivalence
presenting lessons learned from the program, and specifically noting
determination.22 The request can
limitations encountered and the need for additional statutory
authority in this area.
recommended a classification for
the novel device. If the
Source: FDA, “Digital Health Software Precertification (Pre-Cert)
Program,” https://www.fda.gov/medical-devices/digital-health-center-
manufacturer recommends class II,
excellence/digital-health-software-precertification-pre-cert-program.
the request would need to include a
draft proposal for general controls and special controls needed to provide reasonable assurance of
safety and effectiveness, including a description of how the special controls provide such
assurance.23 Upon review of the request, FDA can reclassify the device based on certain risk
classification criteria within 120 days,24 thereby granting marketing authorization of the device
and allowing the device to be used as a predicate device for future novel class II device
submissions.
FDA can decline a De Novo classification request for various reasons. For example, FDA could
determine that there is a legally marketed device that could be used as a predicate device in a
510(k) submission, or that the novel device should be a class III (high risk) device, or that general
controls would be inadequate to control risks, and that special controls to mitigate the risks cannot
be developed.25
FDA has issued guidance to assist manufacturers with the De Novo classification process. Among
other things, the guidance outlines the review process and includes scenarios under which a De
Novo request could and could not be submitted, and when an optional presubmission prior to the
De Novo request may be warranted.26 In December 2018, FDA issued a proposed rule that would
have established regulatory requirements for the De Novo classification process.27 The final De

22 FFDCA §513(f)(2)(A)(ii); 21 U.S.C. §360c(f)(2)(A)(ii).
23 FFDCA §513(f)(2)(A)(v); 21 U.S.C. §360c(f)(2)(A)(v).
24 FFDCA §513(f)(2)(A)(iii); 21 U.S.C. §360c(f)(2)(A)(iii).
25 FFDCA §513(f)(2)(A)(iv); 21 U.S.C. §360c(f)(2)(A)(iv).
26 FDA, Guidance for Industry and Food and Drug Administration Staff: De Novo Classification Process (Evaluation
of Automatic Class III Designation)
, October 5, 2021, https://www.fda.gov/media/72674/download.
27 Food and Drug Administration, HHS, “Medical Device De Novo Classification Process,” 83 Federal Register
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Novo rule outlining procedures and criteria for De Novo requests and a pathway to marketing
authorization was published in the Federal Register on October 5, 2021.28
Medical Device Regulatory Controls
As required by the Medical Device Amendments (MDA), all medical devices are subject to basic
regulatory requirements—general controls—intended to provide reasonable assurance of a
device’s safety and effectiveness. As the risk of the use of a device to a patient increases,
corresponding regulatory requirements are put in place to assure the device is safe and effective—
special controls and premarket approval (PMA). These regulatory controls are described in
greater detail below.
General Controls
General controls are the regulatory requirements that all medical devices are subject to and, taken
together, are intended to ensure that all devices meet the standard of reasonable assurance of
safety and effectiveness
. General controls include a range of premarket and postmarket
requirements.
Some class I and II devices are exempt from certain general controls—specifically, premarket
notification (i.e., a 510(k) submission) and current good-manufacturing practices (i.e., Quality
System [QS] regulation). Each general control, as well these exceptions, is described in further
detail below.
Establishment Registration
Domestic and foreign establishments that manufacture devices must register with FDA. Domestic
establishments are those located in a state or territory of the United States, the District of
Columbia, and the Commonwealth of Puerto Rico. Foreign establishments are those located in
foreign countries and that import or offer for import devices into the United States.29 Generally,
facilities that manufacture the raw materials used in the manufacturing of devices (e.g., valve in a
ventilator) are not required to register with FDA.30
A person who owns or operates a domestic establishment that manufactures devices must register
with FDA and submit specified information. The registration requirement applies regardless of
whether the manufactured device is intended for U.S. commercial distribution.31 A person must
register an establishment upon first engaging in the manufacture of a device, and the
establishment must be registered annually thereafter between October 1 and December 31.32
Registrants must immediately register any additional establishments they own in which a device

63127-63146, December 7, 2018.
28 86 Federal Register 54826, October 5, 2021.
29 21 C.F.R. §207.1.
30 21 C.F.R. §807.65. See also, FDA, “Who Must Register, List, and Pay the Fee,” September 27, 2018,
https://www.fda.gov/medical-devices/device-registration-and-listing/who-must-register-list-and-pay-fee.
31 FDA, “Implementation of Device Registration and Listing Requirements Enacted in the Public Health Security and
Bioterrorism Preparedness and Response Act of 2002, the Medical Device User Fee and Modernization Act of 2002,
and Title II of the Food and Drug Administration Amendments Act of 2007,” 77 Federal Register 45941, August 2,
2012.
32 FFDCA §510(b) and (c); 21 U.S.C. §360(b) and (c).
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is initially manufactured.33 The registration must include the name, place of business, specified
contact information, and all such establishments that engage in the manufacture of a device or
devices.34 FDA regulations specify that registrants must initially register each domestic (and
foreign) establishment no later than 30 days after beginning any process of device manufacturing.
As with domestic facilities, a person who owns or operates an establishment in a foreign country
that manufactures devices for import into the United States must register with FDA upon
engaging in the manufacture of a drug or device, and the establishment must be registered
annually thereafter between October 1 and December 31.35 Such registrants generally must
submit to FDA the same information required for domestic facilities. However, the registration
must also include the name and place of business of the establishment, the name of the U.S. agent
for the establishment, the name of each importer of the device in the United States known to the
establishment, and the name of each person who imports or offers for import the device to the
United States.36 Foreign establishments are required to update their registration information to
reflect any changes in a U.S. agent’s name, address, or phone number within 10 business days.
FDA regulations include additional requirements that apply to both domestic and foreign
establishments. For example, per agency regulations, if covered operations are conducted at more
than one establishment under common ownership and control, the parent, subsidiary, or affiliate
company may submit registration information for all establishments. In addition, registrants are
required to update their registration no later than 30 calendar days after changing the name,
mailing address, or website address (if any) of the device establishment; the name, address, phone
number, fax number, and email address of the owner or operator; the name, address, phone
number, fax number, and email address of the establishment’s official correspondent; or all trade
names used by the establishment.37
Certain entities are exempt from the registration requirements, including pharmacies; licensed
health care practitioners; persons who manufacture devices not for sale but solely for research,
teaching, or chemical analysis; wholesale distributors of devices; and other classes of persons
exempted by FDA by regulation.38
Device Listing
Every person who registers with FDA must, at the time of registration, file with FDA a list of
devices—by their established and proprietary names—being manufactured for commercial
distribution. Device listing generally occurs at two times: (1) at initial registration and listing,
which must occur within 30 days of commencing device manufacturing, and (2) at annual
registration and listing, which occurs between October 1 and December 31 of each year. A
registrant may—but is not required—to make changes to modify the listing information at other
times, such as when a device is first introduced into commercial distribution.39

33 FFDCA §510(d); 21 U.S.C. §360(d).
34 FFDCA §510(b)(2); 21 U.S.C. §360(b)(2); 21 C.F.R. Part 807 Subpart B.
35 FFDCA §510(i); 21 U.S.C. §360(i).
36 FFDCA §510(i)(1)(A)(ii); 21 U.S.C. §360(i)(1)(A)(ii); and 21 C.F.R. Part 807 Subpart C.
37 21 C.F.R. §807.25(b).
38 FFDCA §510(g); 21 U.S.C. §360(g).
39 FDA, “When to Register and List,” December 23, 2017, https://www.fda.gov/medical-devices/device-registration-
and-listing/when-register-and-list.
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Specified information is required at the time of initial listing. Each device in the list must be
accompanied by a brief explanation about why it is not being listed as a drug. In addition, a
reference to the authority under which certain devices are being marketed (e.g., an FDA-assigned
premarket application number), including the reason for not marketing them under certain
authorities, is required.40 A description of each activity or process that contributes to the device
(e.g., manufacturing, sterilization) must be provided, including which part of the process occurred
at which establishment under the owner or operator’s control.41 Regarding labeling and
advertising information, listings for restricted devices—those that can be sold only under
authorization from a licensed health care provider or under conditions specified in regulation—
must include a copy of all labeling and a representative sampling of advertisements. 42 If
requested by FDA for a good cause, a copy of all advertisements for the restricted device must be
submitted. For all other devices, the label and package insert for a device and a representative
sampling of any other labeling must be submitted.43
Each registrant must review and submit additional device listing information on an annual basis
between October 1 and December 31. Registrants must (1) provide a list of devices introduced for
commercial distribution that were not included on any previously submitted list; (2) report if the
manufacture of any previously listed device has been discontinued since the last report (or
resumed if previously discontinued); and (3) report any material change to previously submitted
information.44 Registrants must maintain in a historical file any material changes to labeling or
advertisements made after the initial listing, and must maintain this file in a secure location, with
additional storage requirements as specified in regulation.45
Premarket Notification (510(k))
The Premarket Notification pathway (510(k)) is the most commonly used device premarket
review pathway. In 2017, CDRH cleared 3,173 devices through the 510(k) pathway, representing
82% of the total devices cleared or approved that year.46 Unless subject to a PMA or otherwise
exempt, device manufacturers are required to submit a premarket notification—often referred to
as a traditional 510(k) or 510(k)—at least 90 days prior to marketing the device.47 In general,
most class I devices are exempt from the 510(k) notification requirement (except for “reserved
devices”),48 whereas the majority of, but not all, class II devices are required to have a 510(k)
clearance. A 510(k) submission must demonstrate that the device proposed to be marketed is
substantially equivalent to a device already on the market (i.e., predicate device)—in other words,
the new device must be as safe and effective as the predicate device. Substantial equivalence, as

40 FFDCA §510(j)(1); 21 U.S.C. §360(j)(1).
41 21 C.F.R. §807.25(g).
42 FFDCA §520(e); 21 U.S.C. §360j(e).
43 FFDCA §510(j)(1)(B); 21 U.S.C. §360(j)(1)(B).
44 FFDCA §510(j)(2); 21 U.S.C. §360(j)(2); and 21 C.F.R. §807.22(b)(3) and §807.28.
45 21 C.F.R. §807.26.
46 FDA, “Statement from FDA Commissioner Scott Gottlieb, M.D. and Jeff Shuren, M.D., Director of the Center for
Devices and Radiological Health, on transformative new steps to modernize FDA’s 510(k) program to advance the
review of the safety and effectiveness of medical devices,” November 26, 2018, https://www.fda.gov/news-events/
press-announcements/statement-fda-commissioner-scott-gottlieb-md-and-jeff-shuren-md-director-center-devices-and.
47 FFDCA §510(k), (n)(1); 21 U.S.C. §360(k), (n)(1).
48 FFDCA §510(l)(1); 21 U.S.C. §360(l)(1). This section of the act provides that class I devices are exempt from the
510(k) requirement unless they are “intended for a use that is of substantial importance in preventing impairment of
human health” or they “present(s) a potential unreasonable risk of illness or injury.”
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defined in statute, means that the proposed device has the same intended use as the predicate
device. In addition, the proposed device also must have either the same technological
characteristics—generally materials, design, or energy source—as the predicate device, or must
have different technological characteristics that do not raise different questions of safety and
effectiveness as demonstrated through performance data submitted to FDA showing comparable
safety and effectiveness to the predicate device.49 In other words, substantial equivalence does not
mean that the new device is necessarily identical to the predicate device, and the amount and type
of information required to demonstrate substantial equivalence vary based on the device.50 In
determining substantial equivalence, FDA may consider, as applicable, “intended use, design,
energy used or delivered, materials, chemical composition, manufacturing process, performance,
safety, effectiveness, labeling, biocompatibility, standards, and other characteristics.”51 The type
of data required by FDA to determine substantial equivalence varies by device, particularly when
there are differences between the proposed device and the predicate device (with more differences
likely to require more evidence).52
Once FDA determines that the device to be marketed is substantially equivalent to the predicate
device, the agency provides 510(k) clearance for the device to be marketed and classifies it to the
same class and subsequent regulatory controls as its predicate. Although devices recently cleared
under a 510(k) are commonly used as predicate devices, any legally marketed devices can be used
as predicates. A legally marketed device is (1) a device that was legally marketed prior to May 28,
1976 (preamendments device); (2) a device that has been reclassified from class III to class II or I
through administrative order or De Novo classification (and not exempt from premarket
notification); or (3) a device that has been cleared through the 510(k) process.53 If a manufacturer
makes a significant change to a legally marketed device, the manufacturer may need to submit a
new 510(k) if such a change would affect the safety or effectiveness of the device (e.g., changes
in sterilization, cleaning, or disinfection).54
510(k) Reform
Medical devices that were on the market prior to the enactment of the MDA are termed preamendment devices.
Some preamendment device types were initially regulated as class III devices but were subject to 510(k) clearance
to expedite the review of such a large volume of devices fol owing enactment of the MDA. While this was
intended to be a temporary mechanism, FDA has relied on the 510(k) to clear many devices on the market, as
demonstrated by 2017 data that indicate 82% of marketed devices that have undergone premarket review have
been cleared through a 510(k).55 In 2011, the Institute of Medicine (IOM), now known as the National Academy of

49 FFDCA §513(i)(1)(A); 21 U.S.C. §360(i)(1)(A).
50 FDA, “Premarket Notification 510(k),” https://www.fda.gov/medical-devices/premarket-submissions/premarket-
notification-510k#intro.
51 FDA, “Format for Traditional and Abbreviated 510(k)s,” September 13, 2019, https://www.fda.gov/media/130647/
download, p. 5.
52 FDA, “The 510(k) Program: Evaluating Substantial Equivalence in Premarket Notifications [510(k)],” July 28, 2014,
https://www.fda.gov/media/82395/download, pp. 6-7.
53 21 C.F.R. §807.92(a)(3); and FDA, “Premarket Notification 510(k),” https://www.fda.gov/medical-devices/
premarket-submissions/premarket-notification-510k#intro.
54 FDA, Guidance for Industry and Food and Drug Administration Staff: Deciding When to Submit a 510(k) for a
Change to an Existing Device
, October 25, 2017, https://www.fda.gov/media/99812/download.
55 FDA, “Statement from FDA Commissioner Scott Gottlieb, M.D. and Jeff Shuren, M.D., Director of the Center for
Devices and Radiological Health, on transformative new steps to modernize FDA’s 510(k) program to advance the
review of the safety and effectiveness of medical devices,” November 26, 2018, https://www.fda.gov/news-events/
press-announcements/statement-fda-commissioner-scott-gottlieb-md-and-jeff-shuren-md-director-center-devices-and.
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Medicine, released a report evaluating the 510(k) pathway and concluded that devices being marketed through this
pathway were not being thoroughly evaluated for safety and effectiveness.56
In response to continued concern from stakeholders and reports of adverse events associated with certain
devices,57 FDA, in a November 2018 press release, outlined steps that the agency had taken to help modernize the
510(k) pathway and stated that the agency would consider revising the 510(k) pathway.58 In tandem with this press
release, FDA released a document outlining numerous steps it had taken to strengthen the 510(k) process,
including, among others, increasing its expectations for 510(k) submissions; eliminating the use of over 1,000
510(k) devices as predicate devices; and taking steps to eliminate the use of the 510(k) pathway for class III
devices.59 However, certain changes envisioned by the FDA to revamp the 510(k) pathway may require
congressional action.
There is no standardized 510(k) form or application, but submission format and requirements are
described in regulation60 and guidance.61 Among other things, a 510(k) submission must include
the device name, establishment registration number (if applicable), proposed labeling, a statement
of how the device is similar to and/or different from the predicate device (i.e., a 510(k) summary),
and any other information that FDA deems relevant to make a substantial equivalence
determination.62
Special 510(k) and Abbreviated 510(k)
In 1998, FDA developed the optional Special and Abbreviated 510(k) programs to create more
efficient review processes for certain changes to devices that are subject to 510(k) requirements.
These programs were first described together in a single guidance document,63 but in 2019, FDA
split the programs into two distinct guidance documents.64 Although both pathways are similar to
the traditional 510(k) in that they require demonstration of substantial equivalence by comparing
a new device to a predicate device, they allow for different (and streamlined) methods for
demonstrating substantial equivalence.

56 IOM, Medical Devices and the Public’s Health: The FDA 510(k) Clearance Process at 35 Years, Washington, DC,
July 2011.
57 See, for example, Investigative Consortium of Investigative Journalists (ICIJ), “Medical Devices Harm Patients
Worldwide As Governments Fail On Safety,” November 25, 2018, https://www.icij.org/investigations/implant-files/
medical-devices-harm-patients-worldwide-as-governments-fail-on-safety/.
58 FDA, “Statement from FDA Commissioner Scott Gottlieb, M.D. and Jeff Shuren, M.D., Director of the Center for
Devices and Radiological Health, on transformative new steps to modernize FDA’s 510(k) program to advance the
review of the safety and effectiveness of medical devices,” November 26, 2018, https://www.fda.gov/news-events/
press-announcements/statement-fda-commissioner-scott-gottlieb-md-and-jeff-shuren-md-director-center-devices-and.
59 FDA, “FDA Has Taken Steps to Strengthen The 510(k) Program,” November 2018, https://www.fda.gov/media/
118500/download.
60 21 C.F.R. Part 807 Subpart E.
61 See, for example FDA, Guidance for Industry and Food and Drug Administration Staff: Format for Traditional and
Abbreviated 510(k)s
, September 13, 2019, https://www.fda.gov/media/130647/download, and FDA, Guidance for
Industry and Food and Drug Administration Staff, The 510(k) Program: Evaluating Substantial Equivalence in
Premarket Notifications [510(k)]
, July 28, 2014, https://www.fda.gov/media/82395/download.
62 21 C.F.R. §807.87.
63 FDA, “The New 510(k) Paradigm; Alternate Approaches to Demonstrating Substantial Equivalence in Premarket
Notifications; Availability,” 63 Federal Register 25865, May 11, 1998.
64 FDA, Guidance for Industry and Food and Drug Administration Staff: The Special 510(k) Program, September 13,
2019, https://www.fda.gov/media/116418/download, and FDA, Guidance for Industry and Food and Drug
Administration Staff: The Abbreviated 510(k)
, September 13, 2019, https://www.fda.gov/media/72646/download.
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The Special 510(k) pathway is intended for manufacturers that modify their own legally marketed
devices when such a modification would warrant a new 510(k) submission. However, to be
eligible for a Special 510(k) pathway, the modification must meet specified conditions. Among
other things, FDA needs to be able to evaluate such modifications based on well-established
methods (e.g., methods found in an FDA guidance document), and performance data must be
sufficiently reviewable in a summary or risk analysis format.65 FDA typically reviews such
submissions within 30 days of receipt. If the agency determines that the submission is not
appropriate for a Special 510(k), the submission is converted to a traditional 510(k) and the
submitter is notified.66
The Abbreviated 510(k) is intended for new applicants of devices who can use FDA guidance
documents, special controls (described below in the “Special Controls” section), or voluntary
consensus standards to demonstrate substantial equivalence.67 Voluntary consensus standards are
established by national or international organizations; they are subsequently recognized by FDA
and permissible for use in premarket submissions in accordance with processes specified in
statute and guidance.68 An Abbreviated 510(k) is subject to a 90-day review period by FDA. As
with a Special 510(k), if FDA determines that the submission is not appropriate for an
Abbreviated 510(k), the submission is converted to a traditional 510(k) and the submitter is
notified.69
In February 2019, FDA expanded the concept of the Abbreviated 510(k) to include the Safety and
Performance Based Pathway for certain devices that are well understood. Similar to an
Abbreviated 510(k)’s reliance on FDA guidance, special controls, or voluntary consensus
standards to support substantial equivalence, the Safety and Performance Based Pathway relies on
FDA-identified performance criteria to demonstrate substantial equivalence to a predicate device.
Performance criteria are established by FDA in guidance and are specific to a device type. In
other words, a device is eligible for this pathway only if FDA has finalized a guidance document
specifying performance criteria for that device.70 As of late 2022, FDA has issued nine such final
guidance documents and one such draft guidance.71
Accredited Persons
FDA is required to accredit individuals to review 510(k) submissions and make recommendations
to FDA regarding how a device should be classified.72 Pursuant to this statutory requirement,

65 FDA, Guidance for Industry and Food and Drug Administration Staff: The Special 510(k) Program, September 13,
2019, https://www.fda.gov/media/116418/download, p. 9.
66 FDA, Guidance for Industry and Food and Drug Administration Staff: The Special 510(k) Program, September 13,
2019, https://www.fda.gov/media/116418/download.
67 FDA, Guidance for Industry and Food and Drug Administration Staff: The Abbreviated 510(k), September 13, 2019,
https://www.fda.gov/media/72646/download.
68 FFDCA §514(c); 21 U.S.C. §360d(c). FDA, Guidance for Industry and Food and Drug Administration Staff:
Appropriate Use of Voluntary Consensus Standards in Premarket Submissions for Medical Devices
, September 14,
2018, https://www.fda.gov/media/71983/download.
69 FDA, “How to Prepare an Abbreviated 510(k),” https://www.fda.gov/medical-devices/premarket-notification-510k/
how-prepare-abbreviated-510k.
70 FDA, Guidance for Industry and Food and Drug Administration Staff: Safety and Performance Based Criteria,
September 20, 2019, https://www.fda.gov/media/112691/download.
71 FDA, “Safety and Performance Based Pathway,” https://www.fda.gov/medical-devices/premarket-notification-510k/
safety-and-performance-based-pathway.
72 FFDCA §523(a)(1); 21 U.S.C. §360m(a)(1).
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FDA has established the 510(k) Third Party Review Program to allow accredited third-party
review organizations to review certain low- to moderate-risk medical devices. The voluntary
program is intended to speed up the 510(k) review process, while allowing FDA to focus
resources on reviewing higher-risk devices.73 FDA estimates that about half of 510(k)
applications are eligible for this program. An overview of the 510(k) Third Party Review process
is provided in Figure 1.
Figure 1. The 510(k) Third Party Review Program Process

Source: FDA, “510(k) Third Party Review Program,” https://www.fda.gov/medical-devices/premarket-
submissions/510k-third-party-review-program.
Notes: The sole program payment is made between the 510(k) submitter and the review organization (i.e., a
user fee payment to FDA is not required). FDA generally makes a decision within 30 days after receiving a
recommendation from a review organization.
Accredited organizations must meet certain requirements specified in statute. Among other
things, accredited persons may not be federal government employees, must be independent
organizations not affiliated with device manufacturers, and cannot engage in the manufacture,
design, sale, or promotion of devices.74 FDA keeps an up-to-date list of accredited review
organizations on its website.75
Current Good Manufacturing Practices (Quality System Regulation)
Device manufacturers must comply with current good manufacturing practices (CGMPs) to
assure that their products are safe, effective, and otherwise in compliance with the FFDCA. FDA
may promulgate regulations requiring that, among other things, the manufacture, packaging, and

73 FDA, “510(k) Third Party Review Program,” https://www.fda.gov/medical-devices/premarket-submissions/510k-
third-party-review-program.
74 FFDCA §523(b)(3); 21 U.S.C.§360m(b)(3).
75 FDA, “Current List of FDA-Recognized 510(k) Third Party Review Organizations,” database updated November 16,
2020, https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfthirdparty/accredit.cfm.
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storage of a device conform to CGMPs.76 FDA first promulgated CGMP regulations in 1978. In
1990, to address provisions in the SMDA and conform CGMPs to international medical device
quality system standards, FDA reissued regulations for devices as the quality system (QS)
regulation. The revised regulation went into effect in 1997.77 Among other things, the regulation
includes requirements for design controls, production and process controls, corrective and
preventive action, labeling and packaging controls, storage, and records.78 More recently, the
agency published a proposed rule in February of 2022 to update the QS regulation so it will
“align more closely with the international consensus standard for devices by converging with the
quality management system (QMS) requirements used by other regulatory authorities from other
jurisdictions (i.e., other countries).”79
Because the QS regulation applies to many different device types, it is intended to be broad and
flexible. Rather than prescribing specific CGMPs for each device type, the regulation requires
that manufacturers develop and follow procedures for designing, manufacturing, and distributing
their specific devices. Based on the device type, the manufacturer determine the necessity of
adhering to certain details within the QS regulation framework. Further, some devices are exempt
from most CGMPs, as specified in their respective classification regulation. However, devices
that are exempt from CGMP requirements are still subject to complaint file requirements80 and
general requirements concerning records,81 as specified in the QS regulation.
Records required to be kept to be in compliance with the device QS regulation do not, in general,
need to be proactively reported by manufacturers; however, documentation of CGMPs must be
included in a PMA or PMA supplement application.82 Under most circumstances, compliance
with the QS regulation is assessed during FDA facility inspections. These inspections could
include preapproval inspections for devices subject to a PMA or PMA supplement, risk-based
surveillance inspections intended to assess compliance with CGMPs, or for-cause inspections if
there have been consumer complaints or previous violations regarding CGMPs.
Adulterated and Misbranded Devices
The FFDCA prohibits the adulteration and misbranding of devices, as well as the introduction,
receipt, and delivery of adulterated and misbranded devices into interstate commerce.83
Adulterated Devices
In general, a device is deemed adulterated if
 it consists, in whole or in part, of any filthy, putrid, or decomposed substance;

76 FFDCA §520(f)(1)(A); 21 U.S.C. §360j(f)(1)(A).
77 FDA, “Medical Devices; Current Good Manufacturing Practice (CGMP) Final Rule; Quality System Regulation,” 61
Federal Register 52602, October 7, 1996.
78 21 C.F.R. Part 820.
79 87 Federal Register 10119, February 23, 2022.
80 21 C.F.R. §820.198. Manufacturers must establish and maintain procedures for receiving, reviewing, and evaluating
complaints by a formally designated unit. A complaint is defined as “any written, electronic, or oral communication
that alleges deficiencies related to the identity, quality, durability, reliability, safety, effectiveness, or performance of a
device after it is released for distribution” (21 C.F.R. §820.3).
81 21 C.F.R. §820.180.
82 FFDCA §515(c)(1)(C); 21 U.S.C. §360e(c)(1)(C); 21 C.F.R. §§814.20 and 814.39.
83 FFDCA §301(a)-(c); 21 U.S.C. §331(a)-(c).
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 it has been prepared, packed, or held in insanitary conditions where it may have
been contaminated or otherwise made injurious to health;
 its container is composed, in whole or in part, of any poisonous or deleterious
substance;
 it contains, for coloring purposes only, an unsafe color additive; or
 its strength differs from, or its purity or quality falls below, what it claims to
represent.84
The MDA amended Section 501 of the FFDCA by adding device-specific adulteration provisions
related to other aspects of FDA regulation of devices, including other general controls, special
controls, and PMA requirements.85 Pursuant to changes made by the MDA, a device is also
deemed adulterated if
 it is subject to a performance standard and does not comply with all aspects of
that standard;
 it is a class III device that does not conform with specified PMA application
procedures;
 it is a banned device (discussed below);
 it is in violation of CGMPs; or
 it fails to comply with applicable IDE requirements.86
Misbranded Devices
Many of the misbranding provisions for devices also apply to drugs. In general, a device (or drug)
is misbranded if
 it was manufactured in an establishment that was not properly registered or was
not listed as required;
 its labeling is false or misleading;
 its packaging does not bear a label containing the name and place of business of
the manufacturer, packer, or distributor and an accurate statement of the content
quantities by weight, measure, or numerical count;
 any word, statement, or other required information is not prominently placed on
the labeling or not clearly stated so that it can be read and understood by an
individual under customary conditions of purchase and use;
 its label does not bear adequate directions for use, including warnings against use
in certain pathological conditions or by children, when applicable;
 it is dangerous to health when used in the dosage or manner, or with the
frequency or duration, prescribed, recommended, or suggested in the labeling; or
 it is a color additive used for the purpose of coloring only and does not comply
with relevant packaging and labeling requirements.87

84 FFDCA §501(a)-(c); 21 U.S.C. §351(a)-(c).
85 FDA, “General Controls for Medical Devices,” https://www.fda.gov/medical-devices/regulatory-controls/general-
controls-medical-devices#adulteration.
86 FFDCA §501(e)-(i); 21 U.S.C. §351(e)-(i).
87 FFDCA §502; 21 U.S.C. §352; FDA, “General Controls for Medical Devices,” https://www.fda.gov/medical-
devices/regulatory-controls/general-controls-medical-devices#misbranding.
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Similar to the adulteration provisions, the MDA amended Section 502 of the FFDCA by adding
device-specific misbranding provisions. In general, a device is considered misbranded if
 its name (established or otherwise) is not prominently printed in type at least half
as large as the proprietary name or designation (exemptions may be granted in
certain cases);
 it is marketed without a 510(k) clearance (when applicable);
 a restricted device uses false or misleading advertising or is sold, distributed, or
used in violation of FDA regulations;
 a restricted device manufacturer fails to include specified information in all
advertisements or other descriptive materials;
 it is subject to a performance standard and the labeling does not comply with the
requirements of that standard; or
 it does not comply with other specified requirements of the FFDCA.88
Records and Medical Device Reporting
Medical device manufacturers and importers are required to establish and maintain records and
make reports to assure that medical devices are not adulterated or misbranded and are otherwise
safe and effective.89 Through regulation, FDA can require medical device manufacturers and
importers to report if a medical device may have caused or contributed to death or serious injury,
or malfunctioned in a way that the device would likely cause death or serious injury.90 Required
reports cannot be overly burdensome and cannot disclose the identity of a patient, except under
certain circumstances, among other things.
FDA has promulgated Medical Device Reporting (MDR) regulations that further specify
reporting requirements for device manufacturers, importers, and user facilities. A medical device
manufacturer or importer is required to report device-related deaths, serious injuries, and
malfunctions to FDA, within 30 days of becoming aware of them.91 In addition, an importer is
required to report device-related malfunctions to a manufacturer within 30 days of becoming
aware of them, and a manufacturer is required to submit a report (i.e., a five-day report) to FDA
within five work days of becoming aware of an event that requires “remedial action to prevent an
unreasonable risk of substantial harm to the public health” or a reportable event for which FDA
made a written request.92 A device user facility—a hospital, ambulatory surgical facility, nursing
home, outpatient diagnostic facility, or outpatient treatment facility that is not a physician’s
office—is required to report to FDA and the manufacturer, if known, device-related deaths as
soon as practicable but no later than 10 work days after becoming aware of them. Device-related
serious injuries must be reported to the manufacturer, or FDA if the manufacturer is unknown,
within 10 work days of becoming aware of them.93 If any of these events are reported by a user

88 Ibid.
89 FFDCA §519(a); 21 U.S.C. §360i(a); 21 C.F.R. Part 803.
90 As defined in FFDCA §519(a)(2) (21 U.S.C. §360i(a)(2)), a serious injury is an injury that is life threatening, results
in permanent impairment of body function or damage to a body structure, or requires medical or surgical intervention
to prevent permanent impairment or damage.
91 21 C.F.R. §803.20.
92 21 C.F.R. §803.53.
93 21 C.F.R. §803.30.
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facility, the facility is also required to submit an annual report documenting the total number of
reports attached within that time period, among other things.94
A required report can be submitted in writing or electronically using FDA Form 3500A, with
other information required—as specified in regulation—depending on the type of event and
whether it is the device manufacturer, importer, or user facility reporting the event. All MDR files
are required to be retained by the manufacturer or importer for a period of two years or the shelf
life of the device, whichever is greater. A user facility or distributor is required to retain MDR
files for two years.95 While a device distributor is not subject to reporting requirements, it is
subject to record maintenance requirements.96
In addition to these mandatory reporting (and recordkeeping) requirements, certain entities are
encouraged to voluntarily report adverse events to FDA, as a complement to mandatory reporting
requirements. Although user facilities are required to report device-related deaths, they are not
required to report device malfunctions to FDA or manufacturers, but instead, are encouraged to
do so. Health care professionals may use FDA Form 3500 to submit voluntary reports of
significant adverse events. Patients, caregivers, and consumers may make voluntary reports using
Form 3500B.97 Such voluntary reports are submitted to MedWatch: The FDA Safety Information
and Adverse Event Reporting Program for medical products, and may include instances of
unexpected side effects or adverse events, product quality problems, product use errors, and
therapeutic failures.98
The Manufacturer and User Facility Device Experience (MAUDE) houses both mandatory and
voluntary reports from specified time periods: “voluntary reports since June 1993, user facility
reports since 1991, distributor reports since 1993, and manufacturer reports since August 1996.”99
FDA notes that “MAUDE data is not intended to be used either to evaluate rates of adverse events
or to compare adverse event occurrence rates across devices.”100
Banned Devices
FDA may, by regulation, ban a device if the agency finds that the device presents substantial
deception to users or unreasonable and substantial risk of illness or injury that cannot be corrected
by a labeling change.101 When the agency makes such a determination and subsequently
completes procedures for banning the device,102 the device is subject to a prohibition on current
and future sales, distribution, and manufacture.

94 21 C.F.R. §803.33.
95 21 C.F.R. §803.18.
96 21 C.F.R. §803.1(a).
97 FDA, “Medical Device Reporting (MDR): How to Report Medical Device Problems,” https://www.fda.gov/medical-
devices/medical-device-safety/medical-device-reporting-mdr-how-report-medical-device-problems.
98 FDA, “MedWatch Online Voluntary Reporting Form,” https://www.accessdata.fda.gov/scripts/medwatch/.
99 FDA, “Manufacturer and User Facility Device Experience Database - (MAUDE),” https://www.fda.gov/medical-
devices/mandatory-reporting-requirements-manufacturers-importers-and-device-user-facilities/manufacturer-and-user-
facility-device-experience-database-maude.
100 Ibid.
101 FFDCA §516(a); 21 U.S.C. §360f(a); 21 C.F.R. §895.20.
102 21 C.F.R. Part 895 Subpart A; FDA, “Medical Device Bans,” https://www.fda.gov/medical-devices/medical-device-
safety/medical-device-bans.
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FDA rarely acts on this authority. As of early 2022, FDA regulations ban prosthetic hair fibers,
powdered surgeon’s gloves, powdered patient examination gloves, and absorbable powder for
lubricating a surgeon’s glove.103 FDA used this authority most recently in March 2020, when the
agency published a final rule banning electrical stimulation devices used for self-injurious or
aggressive behavior (and did not ban its use for other purposes, for example, smoking
cessation).104 However, for the first time in the history of the use of this authority, the ban was
overturned by the D.C. Circuit Court of Appeals in July 2021. The court found that FDA could
ban the marketing of a device but could not prohibit only specific uses of a given device that
continues to be marketed, because doing so would stray into the territory of the practice of
medicine, in which the agency is prohibited from interfering.105
Notification and Recall
To protect the public from faulty or fraudulent devices, FDA has the authority to notify certain
individuals and take other actions to ensure that such devices are repaired, replaced, or
refunded.106 A recall—one of these actions—is a method of removing or correcting products that
FDA considers to be in violation of the law. Recall does not include market withdrawal, routine
servicing, or a stock recovery. A market withdrawal is a firm’s removal or correction of a
distributed product for a minor violation that does not violate the law and would not be subject to
legal action by FDA (normal stock rotation practices, routine equipment adjustments and repairs,
etc.). Stock recovery involves correcting a problem before a product is shipped (i.e., is still in the
manufacturer’s control).107
Medical device recalls are almost always conducted voluntarily by a manufacturer after
negotiation with FDA.108 Manufacturers (including refurbishers and reconditioners) and importers
are required to report to FDA any correction or removal of a medical device that is undertaken to
reduce a health risk posed by the device.109 However, a report is not required if one was already
made under the MDR regulations. Additionally, manufacturers and importers must keep records
of those corrections and removals that are not required to be reported to FDA.110 A recall may
involve the removal of all or a portion of the product on the market (such as a single lot). In rare
instances, if a manufacturer or importer does not voluntarily recall a device that poses a risk to
public health, FDA can issue a mandatory recall order to the manufacturer upon determining that
there is a “reasonable probability that a device intended for human use would cause serious,
adverse health consequences or death.”111
When a recall is initiated voluntarily, FDA evaluates the health hazard presented, taking into
account the following factors, among others:112

103 21 C.F.R. Part 895 Subpart B.
104 FDA, “Banned Devices; Electrical Stimulation Devices for Self-Injurious or Aggressive Behavior,” 85 Federal
Register
13312-13354, March 6, 2020.
105 FDA Law Blog, “FDA Medical Device Ban Overturned For the First Time,” https://www.thefdalawblog.com/2021/
07/fda-medical-device-ban-overturned-for-the-first-time/; see FFDCA §1006; 21 U.S.C. §396.
106 FFDCA §518; 21 U.S.C. §360h.
107 FDA, “Recalls, Corrections and Removals (Devices),” https://www.fda.gov/medical-devices/postmarket-
requirements-devices/recalls-corrections-and-removals-devices.
108 21 C.F.R. Part 7.
109 21 C.F.R. Part 806.
110 21. C.F.R. §806.20.
111 FFDCA §518(e); 21 U.S.C. §360h(e); 21 C.F.R. Part 810.
112 21 C.F.R. §7.41.
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 Whether any disease or injuries have occurred from the use of the product.
 Whether any existing conditions could contribute to a clinical situation that could
expose humans or animals to a health hazard.
 Assessment of hazard to various populations (e.g., children, surgical patients,
pets, livestock) that would be exposed to the product.
 Assessment of the degree of seriousness of the health hazard to which the
populations at risk would be exposed.
 Assessment of the likelihood of occurrence of the hazard.
 Assessment of the consequences (immediate or long-range) of the hazard.
Following the health hazard assessment, FDA classifies the recall according to the relative degree
of health hazard. This action can sometimes create some confusion because devices are classified
as class I, II or III as well, but this is an entirely distinct classification process with no relation to
the risk classification of the device. Class I recalls are the most serious, reserved for situations
where there is a reasonable probability that the use of, or exposure to, a product will cause serious
adverse health consequences or death. Class II recalls are for situations where the use of, or
exposure to, a product may cause temporary or medically reversible adverse health consequences,
or where the probability of serious adverse health consequences is remote. In a Class III recall
situation, the use of, or exposure to, a product is not likely to cause adverse health consequences.
A recalling firm must develop a recall strategy that is reviewed and approved by FDA, and that
addresses the depth of the recall, public notification, and effectiveness checks.113 In addition, a
recalling firm must promptly notify all affected parties about the recall, and FDA must “promptly
make available to the public in the weekly FDA Enforcement Report a descriptive listing of each
new recall according to its classification, whether it was Food and Drug Administration-requested
or firm-initiated, and the specific action being taken by the recalling firm.”114
Labeling
All medical devices are required to be labeled in a way that informs a user of how to use the
device. The FFDCA defines a “label” as a “display of written, printed, or graphic matter upon the
immediate container of any article.”115 “Labeling” is defined as “all labels and other written,
printed, or graphic matter upon any article or any of its containers or wrappers, or accompanying
such article” at any time while a device is held for sale after shipment or delivery for shipment in
interstate commerce.116 The term “accompanying” is interpreted to mean more than physical
association with the product; it extends to posters, tags, pamphlets, circulars, booklets, brochures,
instruction books, direction sheets, fillers, and web pages, among other things.117 Accompanying
can also include labeling that is connected with the device after shipment or delivery for shipment
in interstate commerce.

113 FDA, “Recalls, Corrections and Removals (Devices),” https://www.fda.gov/medical-devices/postmarket-
requirements-devices/recalls-corrections-and-removals-devices#5.
114 21 C.F.R. §7.50.
115 FFDCA §201(k); 21 U.S.C. §321(k).
116 FFDCA §201(m); 21 U.S.C. §321(m).
117 FDA, “Device Labeling,” https://www.fda.gov/medical-devices/overview-device-regulation/device-labeling.
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All devices must conform to the general labeling requirements.118 Minimum requirements for the
label include name and place of business, intended use, and adequate directions for use (e.g.,
route or method of application, quantity of dose, route of administration), among others. Some
categories of devices are required to comply with additional or modified requirements (e.g., in
vitro diagnostics and over-the-counter [OTC] devices). Additionally, some specific devices (e.g.,
hearing aids) require special labeling, which may include not only package labeling, but
informational literature, patient release forms, performance testing, and/or specific tolerances or
prohibitions on certain ingredients.119 Various exemptions to the labeling requirements (e.g., for
prescription devices) are outlined in regulation.
Certain sections of the QS regulation also relate to different aspects of labeling.120 For example,
the QS regulation requires that labels remain legible and affixed to the product under normal
conditions of use over the expected life of the device. In addition, the QS regulation addresses
inspection, handling, storage, and distribution of labeling. These requirements, however, do not
generally apply to the adequacy of labeling content, although failure to comply with CGMP
requirements, such as proofreading, may result in labeling content errors.
Unique Device Identification (UDI)
To enhance postmarket surveillance of devices, the FDA Amendments Act of 2007 (FDAAA) and
FDASIA required FDA to issue regulations establishing a unique device identification (UDI)
system for devices.121 This system requires devices to bear a unique identifier to identify the
device through both distribution and use. The UDI system enables rapid identification of a device
and its attributes, especially those that could affect its safety and effectiveness. Among other
things, the UDI system is intended to reduce medical error, simplify integration of device use
information into data systems, and rapidly identify devices with associated adverse events.122
In September 2013, FDA published the final UDI Rule.123 Device labelers (usually, but not
always, the device manufacturer) are required to include a UDI on device labels and packages
(except where specified exceptions apply). In cases where a device is intended for more than one
use and intended to be reprocessed before each use, the device labeler must also place the UDI
directly on the device. A UDI is a unique numeric or alphanumeric code, including both a device
and a production identifier, and it must be placed on labels and packages in both plain text and in
a machine-readable format. A device labeler (or its designated contact) is required to provide
FDA with certain information, which is then entered into the publically available Global Unique
Device Identification Database (GUDID).124

118 21 C.F.R. Part 801.
119 21 C.F.R. §§801.405 - 801.437. These devices include denture repair kits, impact-resistant lenses in sunglasses and
eyeglasses, ozone emission levels, chlorofluorocarbon propellants, hearing aids, menstrual tampons,
chlorofluorocarbons or other ozone-depleting substances, latex condoms, and devices containing natural rubber.
120 21 C.F.R. §820.120.
121 P.L. 110-85 §226(a) amended FFDCA §519 to add a new subsection (f), which directed FDA to issue regulations
establishing a UDI system for devices, as specified. P.L. 112-144 §614 further amended FFDCA §519(f) to establish a
deadline for FDA to promulgate proposed and final regulations.
122 FDA, “Unique Device Identification System,” 78 Federal Register 58785, September 24, 2013.
123 Ibid.; 21 C.F.R. Part 801, Subpart B (Labelling Requirements for Unique Device Identification).
124 21 C.F.R. Part 830 Subpart E (Global Unique Device Identification Database).
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Special Controls
Special controls are the additional regulatory requirements put in place for moderate-risk (class
II) devices because general controls do not provide reasonable assurance of safety and
effectiveness. A special control is generally device-specific, and there must be sufficient
information to establish the special control to provide an assurance of safety and effectiveness.
Such requirements can include, among other things, performance standards, postmarket
surveillance, patient registries, and development and dissemination of guidelines.125
FDA has developed numerous guidance and guideline documents for individual generic device
types (e.g., Antimicrobial Susceptibility Test [AST] systems, bone sonometers) to address the
required special controls. These documents identify specific risks associated with the device type
that are not addressed through general controls and outline FDA’s suggested approaches for
mitigating the identified risks. FDA notes that although manufacturers do not have to follow the
agency’s specific recommendations for mitigating a risk as outlined in a given guidance
document, they must still address the identified risks “by some other means that provides
equivalent assurances of safety and effectiveness.”126
Premarket Approval (PMA)
A PMA is the most stringent device marketing application required by FDA, and it is reserved for
evaluating the safety and effectiveness of a class III medical device prior to marketing. PMA
approval is based on a determination by FDA that the application contains sufficient valid
scientific evidence
to provide reasonable assurance that the device is safe and effective for its
intended use(s).127 FDA defines valid scientific evidence as “evidence from well-controlled
investigations, partially controlled studies, studies and objective trials without matched controls,
well-documented case histories conducted by qualified experts, and reports of significant human
experience with a marketed device, from which it can fairly and responsibly be concluded by
qualified experts that there is reasonable assurance of the safety and effectiveness of a device
under its conditions of use.”128 Approval is based not only on the strength of the scientific data,
but also on inspection of the manufacturing facility to ensure that the facility and the
manufacturing process are in compliance with the QS regulation, among other things.129
A PMA application must include, among other things, indications for use of the device, a device
description, foreign and U.S. marketing history, summary of clinical and nonclinical studies,
conclusions drawn from such studies, proposed labeling, and references to any required
performance or voluntary standards.130 Although the FDA does not provide a preprinted form for
a PMA application, the agency suggests ways to format the application to expedite its
processing.131 To facilitate the submission of required application sections in a serial fashion as
data become available, manufacturers may use a PMA pathway known as the “modular PMA.”132

125 FFDCA §513(a)(1)(B); 21 U.S.C. §360c(a)(1)(B).
126 FDA, “Class II Special Controls Documents,” https://www.fda.gov/medical-devices/guidance-documents-medical-
devices-and-radiation-emitting-products/class-ii-special-controls-documents.
127 FFDCA §513(a)(1)(C); 21 U.S.C. §360c(a)(1)(C); 21 C.F.R. Part 814.
128 21 C.F.R. §860.7.
129 FFDCA §515(d)(2); 21 U.S.C. §360e(d)(2).
130 FFDCA §515(c)(1); 21 U.S.C. §360e(c)(1); 21 C.F.R. §814.20.
131 FDA, “PMA Application Contents,” updated June 3, 2020, https://www.fda.gov/medical-devices/premarket-
approval-pma/pma-application-contents.
132 FFDCA §515(c)(4); 21 U.S.C. §360e(c)(4).
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PMA review is a four-step process
involving (1) an acceptance and
PMA Versus 510(k)
filing review, (2) a substantive
There is a fundamental difference between the PMA and 510(k)
review, (3) a panel review, and (4)
pathways. In a PMA review, FDA directly determines whether the
notification of FDA’s final decision.
device is reasonably safe and effective for its intended use. In a
510(k) review, FDA determines whether the device is substantially
During the first step, FDA notifies
equivalent to another device already on the market. Substantial
the PMA applicant within 45 days
equivalence is determined by comparing the performance
after the application has been
characteristics of a new device with those of a predicate device. To
received whether the application has
be considered substantially equivalent, the new device must have
been filed. An application is suitable
the same intended use and technological characteristics as the
predicate device and cannot raise different questions of safety and
for filing if it contains all
effectiveness.
information required by statute and
regulation.133 FDA will refuse to file an application if, among other things, it contains a false
statement or if the data presented in the application are presented unclearly or incompletely. If
such a refusal occurs, an applicant may resubmit the PMA with additional information or request
an informal conference with the Director of the associated Office of Health Technology to review
the decision not to file the PMA.134
Once an application is determined suitable for filing, FDA generally has 180 days to issue an
order approving or denying the application.135 During substantive review, the second step in the
process, FDA may notify the applicant of any major/minor deficiencies and the applicant may
request to meet with FDA within 100 days of filing to discuss the application.136 Following
substantive review, FDA may refer the PMA to an advisory committee (panel review). In general,
all “first-of-a-kind” devices are taken before the appropriate advisory panel for review and
recommendation.
Advisory committees may be convened to make recommendations on any scientific or policy
matter before FDA.137 The committees are composed of scientific, medical, and statistical experts,
and industry and consumer representatives. An advisory committee meeting allows interested
persons to present information and views at a public hearing.138 FDA typically accepts advisory
committee recommendations for an application (approvable, approvable with conditions, or
nonapprovable). However, there have been cases where FDA’s decision has not been consistent
with the committee’s recommendation. When necessary, CDRH holds joint advisory committee
meetings with other FDA centers. Though FDA regulations allow 180 days to review the PMA
and make a determination, total review time may be longer due to agreement between the
applicant and FDA or specific review times agreed to in a user fee agreement.139

133 21 C.F.R. §814.42(e). FDA may also consider recommendations included in guidance, such as FDA, Guidance for
Industry and Food and Drug Administration Staff: Acceptance and Filing Reviews for Premarket Approval
Applications (PMAs)
, updated December 16, 2019, https://www.fda.gov/media/83408/download.
134 21 C.F.R. §814.42(d).
135 FFDCA §515(d)(1)(A); 21 U.S.C. §360e(d)(1)(A); 21 C.F.R. §814.40.
136 21 C.F.R. §814.44; FDA, Guidance on PMA Interactive Procedures for Day-100 Meetings and Subsequent
Deficiences – for Use by CDRH and Industry
, February 19, 1998, https://www.fda.gov/media/72655/download.
137 For further information, see http://www.fda.gov/AdvisoryCommittees/.
138 21 C.F.R. Part 14.
139 For example, see 1st Quarter FY2016 Package, MDUFA III (FY2013-2017) Performance, February 18, 2015, p. 15,
at http://www.fda.gov/downloads/ForIndustry/UserFees/MedicalDeviceUserFee/UCM487953.pdf. See also 21 C.F.R.
§814.40.
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Least Burdensome Provisions
Congress has directed FDA to take a “least burdensome” approach to medical device premarket evaluation, as
first required in the Food and Drug Administration Modernization Act of 1997 (FDAMA),140 and subsequently
amended by FDASIA and the 21st Century Cures Act. The two provisions added by FDAMA stipulated that FDA
consider the “least burdensome” data or information “necessary” to demonstrate a reasonable assurance of
device effectiveness in a PMA application or substantial equivalence to predicate devices with differing
technological characteristics in certain 510(k) notifications. In 2019 final guidance, FDA defined “least
burdensome” as “the minimum amount of information necessary to adequately address a relevant regulatory
question or issue through the most efficient manner at the right time.”141
Although the original FDAMA provisions focused on the PMA and 510(k) submissions, in 2002 guidance FDA
noted its intention to apply the provisions to all medical device premarket regulatory activities.142 The
amendments made by FDASIA and the 21st Century Cures Act “clarified the original least burdensome provisions
and further recognized the role of postmarket activities as they relate to premarket decisions.”143 In its final 2019
guidance, the agency clarified that “least burdensome principles should be consistently and widely applied to all
medical device regulatory activities in the premarket and postmarket settings”144 and that it wil apply tools to
achieve this goal with respect to activities throughout the device total product lifecycle.
PMA Amendments and Supplements
If changes need to be made to an original PMA submission, either after its approval or pending its
approval, an applicant can submit a PMA supplement or PMA amendment, respectively. If an
applicant already has an approved PMA, a PMA supplement is required for a change that affects a
device’s safety or effectiveness.145 Such changes include, among other things, new indications for
use of the device, labeling changes, use of a different facility to manufacture the device, and
changes in sterilization procedures.146 Based on the change proposed, different types of PMA
supplements can be submitted, as listed in Table 2.
Devices approved via a PMA supplement have smaller fees, shorter review times, and do not
always require the collection of premarket clinical data. Clinical data refers to data obtained
during a clinical trial involving human subjects, whereas preclinical data refers to nonhuman
studies, such as mechanical engineering tests and animal studies. According to some observers,
the features of the PMA supplement “encourage manufacturers to implement evolving
technologies to create new models of devices that are incrementally different from previously
approved additions. This helps facilitate rapid improvement in device technology, but also means
that high-risk medical devices can gain PMA approval as supplements without any direct clinical
study of the specific change made to the device.”147

140 Section 205 of P.L. 105-115.
141 FDA, Guidance for Industry and Food and Drug Administration Staff: The Least Burdensome Provisions: Concepts
and Principles
, February 2019, https://www.fda.gov/media/73188/download.
142 Ibid., p. 6.
143 Ibid.
144 Ibid., p. 7.
145 21 C.F.R. §814.39.
146 21 C.F.R. §814.39(a).
147 Benjamin N. Rome, Daniel B. Kramer, and Aaron S. Kesselheim, “Approval of High-Risk Medical Devices in the
US: Implications for Clinical Cardiology,” Current Cardiology Reports, vol. 16, no. 6 (June 2014), pp. 489-502.
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Table 2. Types of PMA Supplements
Types of Changes
Type of PMA Supplement
Authorization
to Device
Data Needed
Panel-Track
FFDCA §737(4)(B);
Significant design or
Clinical; limited preclinical data
21 C.F.R. §814.39(c) performance
in some cases
change; new
indication
180-Day
FFDCA §737(4)(C);
Significant change in
Preclinical; confirmatory clinical
21 C.F.R. §814.39(a) components,
data in some cases
materials, design,
software, color
additives, or
labeling; for changes
that affect the safety
and effectiveness of
the device
Real-Time
FFDCA §737(4)(D)
Minor change in
Preclinical only
design, software,
sterilization, or
labeling
Special
21 C.F.R. §814.39(d) Labeling change that No specific data requirements
enhances device
safety
30-Day Notice and 135-Day
FFDCA §737(5);
Modifications to
No specific data requirements
21 C.F.R. §814.39(f)
manufacturing that
affect the safety and
effectiveness of the
device; excludes
changes in a
manufacturing/
sterilization site or
to design or
performance
specifications
Manufacturing Site Change
21 C.F.R.
For the use of a
Information submitted to the
§814.39(a)(3)
different facility or
FDA must demonstrate
establishment to
compliance with the Quality
manufacture,
System (QS) Regulation
process, or package
the device
Annual (Periodic) Report or
21 C.F.R. §814.39(e) FDA may allow
In written correspondence,
30-Day
certain changes to
FDA will identify the type of
be reported in an
information that is to be
annual
included in the report
report instead of a
PMA supplement
submission
Source: FDA, “PMA Supplements and Amendments,” https://www.fda.gov/medical-devices/premarket-approval-
pma/pma-supplements-and-amendments; and Benjamin N. Rome, Daniel B. Kramer, and Aaron S. Kesselheim,
“FDA approval of cardiac implantable electronic devices via original and supplement premarket approval
pathways, 1979-2012,” JAMA, vol. 311, no. 4 (January 22/29, 2014), p. 386.

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A PMA amendment is a revision or addition to a PMA or PMA supplement submitted to FDA
before its approval (i.e., to a pending PMA or PMA supplement). An amendment may be
submitted at the initiative of the applicant or FDA, and it includes any additional correspondence
after PMA or PMA supplement approval.148 FDA may extend the review period up to an
additional 180 days with the submission of an amendment by the applicant.149
Investigational Device Exemption (IDE)
An investigational device exemption (IDE) allows a significant-risk device that has not been
authorized for marketing to be used in a clinical study to collect safety and effectiveness data,
which are most commonly used to support a PMA application. 150 A significant-risk device,
among other things, has the potential for serious risk to the health, safety, or welfare of a
subject.151 The IDE also permits these devices to be shipped lawfully for investigation without
requiring the manufacturer to comply with other requirements of the FFDCA requirements, such
as registration and listing.152
As the FFDCA requires,153 FDA has promulgated regulations specifying the procedures and
conditions under which an IDE may be granted.154 An IDE application must include, among other
things, the name and address of the sponsor, a complete report of prior investigations of the
device, and the list of the name, address, and chairperson of each Institutional Review Board
(IRB) that has been or will be asked to review the investigation.155 Once FDA receives the
original application, an IDE number is assigned and the application is considered approved 30
days after it has been received by FDA.156 A sponsor must have received an IDE before initiating
the clinical study and must comply with additional requirements while conducting the study,
including specified labeling of the investigational device, obtaining informed consent for study
participants, and distribution restrictions of the device, among others.157
Certain categories of significant-risk devices are exempt from IDE requirements, such as a device
undergoing consumer preference testing.158 Moreover, nonsignificant-risk devices are those that
do not pose a significant risk to human subjects and, as such, do not require submission of a full
IDE application to proceed with a clinical evaluation.159 However, these devices are required to

148 21 C.F.R. §814.37; FDA, “PMA Supplements and Amendments,” https://www.fda.gov/medical-devices/premarket-
approval-pma/pma-supplements-and-amendments.
149 21 C.F.R. §814.37(c)(1).
150 Most 510(k) submissions do not require clinical data to support the application. See FDA, “Investigational Device
Exemption (IDE),” https://www.fda.gov/medical-devices/how-study-and-market-your-device/investigational-device-
exemption-ide.
151 21 C.F.R. §812.3(m).
152 21 C.F.R. §812.1.
153 FFDCA §520(g)(2); 21 U.S.C. §360j(g)(2).
154 21 C.F.R. Part 812.
155 21 C.F.R. §812.20(b).
156 There are certain circumstances under which FDA may disapprove or withdraw an IDE application. See FDA,
Guidance for Sponsors, Clinical Investigators, Institutional Review Boards, and Food and Drug Administration Staff:
FDA Decisions for Investigational Device Exemption Clinical Investigations, August 2014, https://www.fda.gov/
media/81792/download.
157 21 C.F.R. Parts 50 and 812. See also FDA, “IDE Approval Process,” https://www.fda.gov/medical-devices/
investigational-device-exemption-ide/ide-approval-process.
158 21 C.F.R. §812.2(c).
159 FDA, “IDE Approval Process,” https://www.fda.gov/medical-devices/investigational-device-exemption-ide/ide-
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comply with abbreviated IDE requirements, such as certain labeling requirements and IRB
approval.160
Facilitating Access to Medical Devices
Congress has authorized in statute certain pathways to allow for timely access to devices needed
most by vulnerable populations. For example, Congress created the Humanitarian Device
Exemption (HDE) to encourage the development of devices intended to treat and diagnose rare
diseases and conditions. To expand access to innovative devices, Congress subsequently
established the Breakthrough Device Pathway, which led to FDA creating the Breakthrough
Devices Program. These efforts are described further below.
Humanitarian Device Exemption
For diseases that occur in a small number of patients, device manufacturers may find it difficult to
provide sufficient data typically needed for device marketing applications. In response, Congress
first authorized the HDE in the Safe Medical Devices Act of 1990 (P.L. 101-629). An HDE is an
exemption from the effectiveness requirements of a PMA for a humanitarian use device (HUD)
intended to treat or diagnose a condition affecting fewer than 4,000 individuals in the United
States.161 Subsequent legislation (i.e., FDAMA, FDAAA, the 21st Century Cures Act, and
FDARA) made changes to the HDE program. For example, perhaps most significantly, the 21st
Century Cures Act (P.L. 114-255), among other things, expanded the scope of the HDE by
allowing it to apply to conditions affecting fewer than 8,000 (rather than 4,000) individuals.162
FDA may approve an HDE application for use of a HUD in clinical care under specified
circumstances. Such circumstances include if (1) the device (as mentioned above) is designed to
treat or diagnose a disease or condition affecting less than 8,000 individuals in the United States,
(2) the device would not be available unless the exemption is otherwise granted and there is no
comparable device to treat the disease or condition, and (3) the benefits of the device outweigh
the risks.163 FDA is required to approve or deny HDE requests no later than 75 days after it
receives them. If an HDE is granted, the HUD may be used only under specified circumstances,164
including that it must be used only in a health care facility with Institutional Review Board (IRB)
oversight. In addition, the HDE holder may need to demonstrate continued compliance with
certain requirements to maintain the HDE.165
With the exception of certain, mostly pediatric, devices, a HUD may not be sold for an amount
that exceeds the cost of the research, development, fabrication, and distribution of the device.166 If
a HUD is eligible to be sold for profit, the number of devices that may be sold is limited to the
number of devices needed to treat 8,000 individuals, otherwise known as the annual distribution

approval-process.
160 21 C.F.R. §812.2(b).
161 FFDCA §520(m); 21 U.S.C. §360j(m).
162 Section 3052 of P.L. 114-255.
163 FFDCA §520(m)(2); 21 U.S.C. §360j(m)(2); 21 C.F.R. Part 814 Subpart H.
164 FFDCA §520(m)(4); 21 U.S.C. §360j(m)(4).
165 FFDCA §520(m)(5); 21 U.S.C. §360j(m)(5).
166 FFDCA §520(m)(3), (6); 21 U.S.C. §360j(m)(3), (6).
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number (ADN). FDA provides the ADN number to the requestor upon HDE approval, but the
requestor may petition FDA to modify the ADN in an HDE supplement.167
Breakthrough Device Designation
Pursuant to FFDCA Section 515B—added by the 21st Century Cures Act and amended by the
FDA Reauthorization Act of 2017 (FDARA; P.L. 115-52)—FDA can expedite development and
prioritize review of certain devices and device-led combination products designated as a
“breakthrough device.” Such devices would (1) provide more effective diagnosis or treatment of a
life-threatening or irreversibly debilitating condition, and (2) represent breakthrough technologies
for which no approved alternatives exist, offer significant advantages over existing alternatives,
or are in the best interest of patients.168 The Breakthrough Device Program includes two phases:
(1) the Designation Request phase, in which a sponsor formally requests that a device receive a
“breakthrough” designation, and (2) “actions to expedite development of the device and the
prioritized review of subsequent regulatory submissions.”169
This program supersedes the former Priority Review Program and the Expedited Access Pathway
(EAP) that together provided priority review for certain PMA applications, as well as support for
development and review of breakthrough technologies. Devices designated under the EAP are
now part of the Breakthrough Device Program, given similarities in the two programs.
The sponsor of a device or device-led combination product may request “breakthrough device”
designation any time prior to review of a 510(k), PMA, or De Novo application. FDA’s senior
staff and managers must review the request, and the agency is required to make a decision within
60 calendar days.170 If a request is approved, a team of FDA staff with relevant expertise are
assigned to oversee the expedited development and premarket review of a device. As required by
the 21st Century Cures Act, FDA issued guidance regarding implementation of the Breakthrough
Device Program in December of 2018.171 The guidance outlines overall program principles, ,
including, for example, timely and interactive communication, efficient and flexible clinical study
design, senior management engagement, and manufacturing considerations for PMA
submissions.172
Postmarket Surveillance
FDA’s premarket review process is not designed to completely ensure the safety of all medical
devices before they enter the market. Therefore, it is necessary to have a strong surveillance
system that monitors device safety once they enter the market and clinical use. When a problem is

167 FDA, Guidance for Industry and Food and Drug Administration Staff: Humanitarian Device Exemption (HDE)
Program
, September 6, 2019, https://www.fda.gov/media/74307/download, pp. 24-26.
168 FFDCA §515B(b); 21 U.S.C. §360e-3(b).
169 FDA, “Guidance for Industry and Food and Drug Administration Staff: Breakthrough Devices Program,” December
2018, https://www.fda.gov/media/108135/download, p. 2.
170 FFDCA §515B(d); 21 U.S.C. §360e-3(d).
171 FDA, “Guidance for Industry and Food and Drug Administration Staff: Breakthrough Devices Program,” December
2018, https://www.fda.gov/media/108135/download.
172 In October 2022, FDA published draft guidance to propose making changes to the Breakthrough Devices Program,
specifically to clarify the program’s applicability to certain devices that might benefit populations affected by health
disparities, among other things. FDA, “Select Updates for the Breakthrough Devices Program Guidance: Reducing
Disparities in Health and Health Care,” October 21, 2022, https://www.fda.gov/media/162413/download.
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identified, various corrective actions may be implemented, such as removing the device from the
market, changing the device labeling and instructions for use, or improving user training. FDA’s
postmarket surveillance activities currently include mandated studies; adverse event reporting, or
passive surveillance; and, more recently, efforts to develop active surveillance of medical devices
in real-world settings.
Active surveillance “involves proactively obtaining and rapidly analyzing information occurring
in millions of individuals recorded in large healthcare data systems to verify safety signals
identified through passive surveillance or to detect additional safety signals that may not have
been reported as adverse events to passive surveillance systems.”173 Passive surveillance which
may be voluntary or mandatory, relies on unsolicited reports of adverse events that are sent to a
central database or health authority. By definition, passive surveillance relies on outside entities
(e.g., manufacturers, users, or importers).174 In general, more robust passive surveillance relies on
a combination of voluntary and mandatory systems or mechanisms, as is the case with FDA’s
postmarket surveillance systems for medical devices.
Relying on only passive mechanisms for the postmarket surveillance of medical devices such as
traditional adverse event reporting systems—and to identify potential issues with devices for
further investigation—may provide incomplete information. Moreover, passive surveillance may
flag a possible issue or overemphasize certain safety signals, while missing others. Active
surveillance, on the other hand, may decrease the burden on regulated entities, provide
information in real-time, and provide more complete information about a device’s overall safety
and effectiveness profile. The use of both active and passive surveillance systems—in concert
with targeted mandated studies based on findings from these systems—likely provides the most
robust system of postmarket surveillance for devices.
Mandatory Postmarket Studies
Postmarket studies can help fill gaps in premarket data about a given device, and can help
manufacturers respond to safety concerns identified through either active or passive surveillance
systems (e.g., MDR or NEST). FDA can order two primary types of mandatory postmarket
studies: so-called “522 studies” (also referred to as postmarket surveillance studies) and Post-
Approval Studies (PAS). These studies differ in some respects, but both are an important
component of the agency’s overall medical device postmarketing surveillance activities.
Researchers have found that mandatory postmarket studies “have often been difficult to
implement and complete reliably.”175 For example, a “key challenge in conducting these studies is
a lack of incentives for clinicians and patients to participate, because they represent already
marketed devices and an additional reporting burden and other requirements on top of their usual
practice.”176 A September 2015 GAO study described “(1) the types of devices for which FDA

173 FDA, “COVID-19 Vaccine Safety Surveillance,” https://www.fda.gov/vaccines-blood-biologics/safety-availability-
biologics/covid-19-vaccine-safety-surveillance.
174 Ibid.
175 The Brookings Institution, Engelberg Center for Health Care Reform, Strengthening Patient Care: Building an
Effective National Medical Device Surveillance System
, Washington, DC, February 2015, p. 12,
http://www.brookings.edu/~/media/research/files/papers/2015/02/23-medical-device-policy-surveillance/med-device-
report-web.pdf.
176 The Brookings Institution, Engelberg Center for Health Care Reform, Strengthening Patient Care: Building an
Effective National Medical Device Surveillance System
, Washington, DC, February 2015, p. 12,
http://www.brookings.edu/~/media/research/files/papers/2015/02/23-medical-device-policy-surveillance/med-device-
report-web.pdf.
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has ordered a postapproval study and the status of these studies, and (2) the types of devices for
which FDA has ordered a postmarket surveillance study and the status of these studies.”177 GAO
analyzed FDA data on 313 postapproval studies that FDA ordered between January 1, 2007, and
February 23, 2015. Of the 313 postapproval studies, GAO found that 225 (72%) were ongoing,
62 (20%) were completed, and 26 (8%) were inactive.178 Of the 225 ongoing studies, 81% were
making adequate progress and 19% were delayed due to, for example, limited patient
enrollment.179 GAO also analyzed FDA data on 392 postmarket surveillance studies that FDA
ordered between May 1, 2008, and February 24, 2015. GAO found that 88% of the 392
postmarket surveillance studies were inactive, 10% were ongoing, and 2% were completed.180
Partially prompted by the GAO study’s findings, FDA released updated draft guidance documents
for both 522 studies and PAS in May 2021. The draft guidance on 522 studies aims to increase
transparency, as well as to provide information on how to fulfill Section 522 obligations.181 The
draft guidance on PAS includes recommendations concerning the format, content, and review of
PAS-related submissions, along with modified review-time goals for PAS-related submissions,
among other things.182 These guidance documents were finalized in October 2022.183
522 Studies
FDA has the authority to require, by order, manufacturers to conduct mandatory post-market
studies to evaluate specific aspects of or overall device performance after device marketing—also
called a 522 study, after the relevant section in the FFDCA. The order may be issued either at the
time of a device’s approval or clearance, or at any other time thereafter. FDA can determine the
need for a 522 study based on many different reasons, including “analysis of adverse event
reports, a recall or corrective action, post-approval data, review of premarket data, reports from
other governmental authorities, or review of scientific literature.”184
Specifically, for certain class II and class III devices, FDA may order a manufacturer to conduct a
postmarket surveillance study for an approved or cleared device in order to gather additional
safety and effectiveness data.185 A postmarket surveillance study may be ordered for class II or
class III devices if
 device failure would be reasonably likely to have serious adverse health
consequences;

177 U.S. Government Accountability Office, Medical Devices: FDA Ordered Postmarket Studies to Better Understand
Safety Issues, and Many Studies Are Ongoing
, GAO-15-815, September 2015. For purposes of the GAO report, the
term “postmarket surveillance studies” refers to studies under the authority of FFDCA Section 522.
178 Ibid., p. 14.
179 Ibid., p. 15.
180 Ibid., p. 20.
181 FDA, Postmarket Surveillance Under Section 522 of the Federal Food, Drug, and Cosmetic Act,” May 27, 2021,
https://www.fda.gov/media/149346/download.
182 FDA, “Procedures for Handling Post-Approval Studies Imposed by Premarket Approval Application Order,” May
26, 2021, https://www.fda.gov/media/149340/download.
183 FDA, “Postmarket Surveillance Under Section 522 of the Federal Food, Drug, and Cosmetic Act,” October 7, 2022,
https://www.fda.gov/media/81015/download; and FDA, “Procedures for Handling Post-Approval Studies Imposed by
Premarket Approval Application Order,” October 7, 2022, https://www.fda.gov/media/71327/download.
184 FDA, “Postmarket Surveillance Under Section 522 of the Federal Food, Drug, and Cosmetic Act,” October 7, 2022,
https://www.fda.gov/media/81015/download, p. 6.
185 FFDCA §522(a); 21 U.S.C. §360l(a).
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 the device is expected to have significant use in pediatric populations;
 the device is intended to be implanted in the body for more than one year; or
 the device is intended to be a life-sustaining or life-supporting device used
outside a device user facility.186
A specific class II or class III device may be the subject of one or more requirements under a 522
order. Mandated 522 studies are not a condition of clearance or approval for most medical
devices; however, FDA may require a 522 study as a condition of clearance or approval for a
device with significant use in pediatric populations.187 This is in contrast with Post-Approval
Studies (described in the next section), which are a condition of an approval pursuant to a PMA or
HDE.
Generally, manufacturers are required to submit a plan for postmarket surveillance to FDA for
approval within 30 days of receiving a 522 order, and must begin any required postmarket
surveillance not later than 15 months after being so ordered.188 Manufacturers are required to
provide certain reports during a 522 study, including interim reports to provide status updates, as
well as a final postmarket surveillance report. FDA generally responds to the final report within
60 days, indicating either that the obligations under the order have been fulfilled, or that
additional actions may be required (e.g., labeling change).189
Post-Approval Studies
As a condition of approval for a PMA or an HDE, FDA may include a requirement for a post-
approval study to obtain additional information on device safety, effectiveness, and/or reliability
over long-term use of the device in real world populations.190 Specifically, FDA can impose these
requirements either in a PMA approval order, in regulation at the time of a PMA approval order,
or through regulation after the PMA approval order.191 Specifically, regulation notes that the
agency may require “continuing evaluation and periodic reporting on the safety, effectiveness,
and reliability of the device for its intended use” and “such other requirements as FDA determines
are necessary to provide reasonable assurance, and continuing reasonable assurance, of the safety
and effectiveness of the device.”192 A device may be the subject of one or more required post-
approval studies imposed by an approval order. If a manufacturer fails to comply with these post-

186 FFDCA §522(a)(1)(A); 21 U.S.C. §360l(a)(1)(A). A device user facility means a hospital, ambulatory surgical
facility, nursing home, or outpatient treatment facility that is not a physician’s office.
187 FFDCA §522(a)(1)(B); 21 U.S.C. §360l(a)(1)(B). A pediatric population is defined “to mean patients who are 21
years of age or younger at the time of diagnosis or treatment, that is, from birth through the twenty-first year of life, up
to, but not including the patient’s twenty-second birthday.” FDA, “Postmarket Surveillance Under Section 522 of the
Federal Food, Drug, and Cosmetic Act,” October 7, 2022, https://www.fda.gov/media/81015/download, p. 7.
188 FDA, “Postmarket Surveillance Under Section 522 of the Federal Food, Drug, and Cosmetic Act,” October 7, 2022,
https://www.fda.gov/media/81015/download, p. 13.
189 Ibid., p. 22.
190 For further information, see FDA, “Procedures for Handling Post-Approval Studies Imposed by Premarket Approval
Application Order,” October 2022, https://www.fda.gov/media/71327/download; and Post-Approval Studies,
http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/PostmarketRequirements/PostApprovaStudies/
default.htm.
191 21 C.F.R. §814.82(a).
192 21 C.F.R. §814.82(a)(2) and (9).
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approval study requirements, as imposed through a PMA or HDE order, the agency is authorized
to withdraw the approval.193
Adverse Event Reporting
To date, FDA has relied on passive surveillance mechanisms to identify safety and other concerns
with medical devices on the market. These mechanisms, which may be mandatory or voluntary,
rely on a number of different entities, including device manufacturers, hospitals, health care
providers, and patients themselves. FDA has taken steps to make reporting easier, for example by
developing different reporting forms for different entities, establishing electronic Medical Device
Reporting, and establishing a voluntary quarterly summary reporting option in certain cases for
MDR reports.
Adverse event reporting requirements began with passage of the Safe Medical Devices Act of
1990 (SMDA, P.L. 101-629), which required FDA to establish a system for monitoring and
tracking serious adverse events that resulted from the use or misuse of medical devices.194 As
noted above, MDR is one mechanism that FDA uses to identify and monitor significant adverse
events involving medical devices,195 and which involves variable reporting requirements for
device manufacturers, user facilities, and importers.196
In August 2009, FDA published notice of a proposed rule, as well as a related draft guidance
document, that would require manufacturers to submit MDRs to the agency in an electronic
format.197 According to FDA, the proposed regulatory changes would provide the agency with an
efficient data entry process that would facilitate timely access to adverse event information for
medical devices and identification of emerging public health issues. The device industry
requested a longer time frame to implement the changes. In February 2014, FDA published a final
rule on Electronic Medical Device Reporting (eMDR) requiring manufacturers and importers to
submit MDRs to the agency in an electronic format.198 User facilities may also submit eMDR
reports, but the final rule allows user facilities to continue to submit paper MDR reports.199

193 21 C.F.R. §814.82(c).
194 FFDCA §519(a); 21 U.S.C. §360i.
195 The searchable MDR database for devices is available at http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmdr/
search.CFM.
196 Device manufacturers are required to report to FDA (1) within 30 calendar days of acquiring information that
reasonably suggests one of their devices may have caused or contributed to a death, serious injury, or malfunction and
(2) within 5 working days if an event requires action other than routine maintenance or service to prevent a public
health issue [21 C.F.R. §803.10(c)(1) and §803.10(c)(2)]. Importers are required to report deaths and serious injuries
within 30 days to both FDA and the manufacturer; reports of malfunctions have to be made only to the manufacturer,
also within 30 days [21 C.F.R. §803.10(b)]. User facilities, such as hospitals and nursing homes, are also required to
report deaths to both the manufacturer, if known, and FDA within 10 working days [21 C.F.R. §803.10(a)(1)(i)]. User
facilities must report serious injuries to the manufacturers (or FDA if the manufacturer is unknown) within 10 working
days [21 C.F.R. §803.10(a)(1)(ii)]. User facilities must also submit annual reports to FDA of all adverse event reports
sent to manufacturers or FDA in the past year [21 C.F.R. §803.10(a)(2) and §803.33].
197 FDA, “Proposed Rule, Medical Device Reporting: Electronic Submission Requirements,” 74 Federal Register
42203-42217, August 21, 2009; and FDA, “Draft Guidance for Industry, User Facilities, and Food and Drug
Administration Staff; eMDR—Electronic Medical Device Reporting; Availability,” 74 Federal Register 42310, August
21, 2009.
198 79 Federal Register 8832, February 14, 2014.
199 For further information, see http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/
PostmarketRequirements/ReportingAdverseEvents/eMDR–ElectronicMedicalDeviceReporting/default.htm.
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In August 2018, FDA finalized an alternative format for reporting MDRs. The Voluntary
Malfunction Summary Reporting Program was developed in response to goals outlined in the
MDUFA IV commitment letter for streamlining malfunction reporting.200 This option allows
certain groups of reports to be summarized and submitted on a quarterly basis. There are many
exceptions to this alternative form of reporting, including, for example, that reports of death or
serious injury still must be made separately.201
National Evaluation System for Health Technology (NEST) and
Real-World Evidence (RWE)
Although mandated studies and passive surveillance methods provide useful information to
monitor the safety and effectiveness of devices postmarket, they have limitations; for example,
the data on medical devices come from “disparate data sources with variable data elements, data
definitions, data quality, and frequently from only limited subsets of patient exposures.”202 In light
of these and similar concerns, a 2011 Institute of Medicine (now called the National Academies
of Medicine) report recommended that FDA “develop and implement a comprehensive strategy to
collect, analyze, and act on medical-device postmarket performance information.”203
In response, FDA released a report in September 2012 outlining the parameters of a new national
system for all stakeholders involved in the use of medical devices—patients, physicians,
hospitals, payers, manufacturers, and regulators—that would rely on Real-World Data (RWD).204
The September 2012 report described “FDA’s vision” for the creation of a national system
focused on medical devices that “would augment, not replace, other mechanisms of surveillance
such as FDA’s MDR and MedSun.”205 The new national system would conduct “active
surveillance in near real-time using routinely collected electronic health information containing
unique device identifiers,” quickly identify “poorly performing devices,” accurately characterize
the “real-world clinical benefits and risks of marketed devices,” and facilitate the “development
of new devices and new uses of existing devices through evidence generation, synthesis and
appraisal.”206
FDA’s September 2012 report proposed four specific actions to strengthen the U.S. medical
device postmarket surveillance system:

200 FDA, “MDUFA PERFORMANCE GOALS AND PROCEDURES, FISCAL YEARS 2018 THROUGH 2022,”
December 2, 2016, https://www.fda.gov/media/102699/download, p. 18.
201 See generally FDA, “Medical Device Reporting (MDR): How to Report Medical Device Problems,”
https://www.fda.gov/medical-devices/medical-device-safety/medical-device-reporting-mdr-how-report-medical-device-
problems#voluntary.
202 The Medical Device Registry Task Force and the Medical Devices Epidemiology Network, Recommendations for a
National Medical Device Evaluation System, Draft for Public Comment
, August 20, 2015, p. 9.
203 IOM, Medical Devices and the Public’s Health: The FDA 510(k) Clearance Process at 35 Years, Washington, DC,
July 2011, Recommendation 7-2.
204 FDA defines RWD as “data relating to patient health status and/or the delivery of health care routinely collected
from a variety of sources.” See FDA, “Use of Real-World Evidence to Support Regulatory Decision-Making for
Medical Devices,” August 31, 2017, https://www.fda.gov/media/99447/download, p. 4.
205 FDA, Strengthening Our National System for Medical Device Postmarket Surveillance, Silver Spring, MD,
September 2012, http://www.fda.gov/downloads/AboutFDA/CentersOffices/OfficeofMedicalProductsandTobacco/
CDRH/CDRHReports/UCM301924.pdf, p. 8.
206 FDA, Strengthening Our National System for Medical Device Postmarket Surveillance, Silver Spring, MD,
September 2012, http://www.fda.gov/downloads/AboutFDA/CentersOffices/OfficeofMedicalProductsandTobacco/
CDRH/CDRHReports/UCM301924.pdf.
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 establish a UDI system and promote its
Sentinel System
incorporation into electronic health
Pursuant to Section 905 of the FDAAA, FDA was
information;
required to establish an Active Postmarket Risk
 promote the development of national and
Identification and Analysis (ARIA) in order to link
international device registries for selected
and analyze safety data from multiple sources.209
In response to this requirement, in May 2008,
products;
FDA launched the Sentinel Initiative to create a
 modernize adverse event reporting and
national electronic system for medical product
analysis; and
safety surveillance. The ful system was available in

February 2016.210 While Section 615 of FDASIA
 develop and use new methods for evidence directed FDA to include medical devices in the
generation, synthesis, and appraisal.207
Sentinel Initiative, the system appears to be used
only in certain circumstances as a complement to
In subsequent reports, FDA and its partners have
other FDA medical device surveillance databases,
further refined this vision and provided updates on
such as MAUDE and NEST.211
efforts to create a new system for medical device
surveillance and evaluation. The reports discuss ways to implement the system as a whole,
including the role of a coordinating center, a seven-year implementation plan, and several pilot
programs.208 These ideas and early steps have helped establish the National Evaluation System for
Health Technology (NEST) Coordinating Center (NESTcc) and of many of its current activities.
FDA continues to work with relevant stakeholders to support NEST, a collaborative database
intended to “link and synthesize data from different sources across the medical device landscape,
including clinical registries, electronic health records, and medical billing claims.”212 Although
the system builds upon requirements authorized in statute (e.g., unique device identification),213
this effort appears to be FDA-initiated. The development of NEST was included in CDRH’s
2016-2017 Strategic Priorities,214 and in 2016 FDA awarded funding to the Medical Device
Innovation Consortium (MDIC) to establish NESTcc.215 NESTcc “provides governance for the
NEST ecosystem, oversees infrastructure building, promotes standards, and monitors
progress.”216 FDA has noted that NESTcc is working to “develop the infrastructure needed to

207 FDA, Strengthening Our National System for Medical Device Postmarket Surveillance, Silver Spring, MD,
September 2012, http://www.fda.gov/downloads/AboutFDA/CentersOffices/OfficeofMedicalProductsandTobacco/
CDRH/CDRHReports/UCM301924.pdf, pp. 4 and 8.
208 For additional information see FDA, Remarks by Robert Califf to the Medical Device Manufacturers Association,
May 5, 2016, at http://www.fda.gov/NewsEvents/Speeches/ucm499546.htm; National Evaluation System, at
http://www.fda.gov/AboutFDA/CentersOffices/OfficeofMedicalProductsandTobacco/CDRH/CDRHReports/
ucm301912.htm; and Jeffrey Shuren and Robert M. Califf, “Need for a National Evaluation System for Health
Technology,” JAMA, published online July 11, 2016.
209 FFDCA §505(k)(3); 21 U.S.C. §355(k)(3).
210 FDA, “FDA’s Sentinel Initiative,” https://www.fda.gov/safety/fdas-sentinel-initiative.
211 Sentinel, “Devices & Radiological Health Assessments,” https://www.sentinelinitiative.org/assessments/devices-
radiological-health#section-1592428975873.
212 FDA, “National Evaluation System for health Technology (NEST),” https://www.fda.gov/about-fda/cdrh-reports/
national-evaluation-system-health-technology-nest.
213 FFDCA §519(f); 21 U.S.C. §360i(f).
214 FDA, “2016-2017 Strategic Priorities Center for Devices and Radiological Health,” pp. 5-6, https://www.fda.gov/
media/95317/download.
215 MDIC, “Medical Device Innovation Consortium (MDIC) Awarded $3 million for National Evaluation System for
health Technology Coordinating Center,” September 13, 2016, https://mdic.org/wp-content/uploads/2016/09/Final-
Press-Release-MDIC-awarded-NEST-Coordinating-Center-20160913.pdf.
216 FDA, “National Evaluation System for health Technology (NEST),” https://www.fda.gov/about-fda/cdrh-reports/
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establish an active surveillance system that can be utilized by FDA and other stakeholders.”217
This work has included evaluations of more than 20 test cases in various areas, including (1)
exploring the feasibility of device manufacturers using RWD and Real-World Evidence (RWE)218
for various pre- and postmarket regulatory activities, (2) publishing Data Quality and Methods
Frameworks, and (3) accepting proposals for the development of active surveillance cloud
infrastructure.219
The information generated through NEST may be used not only for purposes of postmarket
surveillance, but it may also be used to support premarket regulatory decision-making and
expanded indications for use after clearance or approval, among other things. On July 27, 2016,
FDA released draft guidance—and final guidance in August 2017—explaining how
manufacturers may use RWD to support development of RWE to meet regulatory requirements
and supporting regulatory decisions across the total product life cycle (TPLC) of a device.220 FDA
defines RWD as “data relating to patient health status and/or the delivery of health care routinely
collected from a variety of sources,”221 and notes that such sources may include, for example,
“administrative and healthcare claims, electronic health records, data obtained as part of a public
health investigation or routine public health surveillance, and registries.”222 The guidance outlines
the characteristics of RWD that are important to the agency, and identifies several examples of
regulatory decision-making where RWE derived from such data may be used. In addition, in
March 2021, CDRH published an analysis of the use of RWE in regulatory decisions for medical
devices from 2012 to 2019 using 90 different device examples.223 The “examples come from the
full continuum of clinical and device areas throughout CDRH and across the medical device total
product life cycle but do not comprise an exhaustive list of all submissions that have relied on
RWE.”224

national-evaluation-system-health-technology-nest.
217 Department of Health and Human Services, “Fiscal Year 2022 FDA Justification of Estimates for Appropriations
Committees,” https://www.fda.gov/media/149616/download, p. 191.
218 FDA defines real world evidence as “the clinical evidence regarding the usage, and potential benefits or risks, of a
medical product derived from analysis of RWD.” See FDA, “Use of Real-World Evidence to Support Regulatory
Decision-Making for Medical Devices,” August 31, 2017, https://www.fda.gov/media/99447/download, p. 4.
219 NEST, “NEST Coordinating Center: About Us,” https://nestcc.org/about/about-us/.
220 FDA, “Use of Real-World Evidence to Support Regulatory Decision-Making for Medical Devices,” August 31,
2017, https://www.fda.gov/media/99447/download.
221 Ibid., p. 4.
222 Ibid., p. 4.
223 FDA, “Examples of Real-World Evidence (RWE) Used in Medical Device Regulatory Decisions,”
https://www.fda.gov/media/146258/download.
224 FDA, “Leveraging Real World Evidence in Regulatory Submissions of Medical Devices,” March 16, 2021,
https://www.fda.gov/news-events/fda-voices/leveraging-real-world-evidence-regulatory-submissions-medical-devices.
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Appendix A. History of Laws Governing Medical
Device Regulation

The Federal Food, Drug and Cosmetic Act of 1938 (FFDCA)
The first general federal food and drug law, the Food and Drugs Act of 1906 (P.L. 59-384), did
not contain any provisions to regulate medical device safety or claims made regarding such
devices. Strong support for reform developed during the 1930s due to “false therapeutic claims
for medical devices [that] were being presented to the public through radio and newspaper
advertising.”225 Medical devices came under federal scrutiny when Congress passed the Federal
Food, Drug and Cosmetic Act (FFDCA) of 1938 (P.L. 75-717). The regulatory authority provided
to FDA by the 1938 law was “limited to action after a medical device has been offered for
introduction into interstate commerce” and only when the device was deemed to be “adulterated
or misbranded.”226
Most of the legitimate devices on the market at the time the 1938 act became law “were relatively
simple items which applied basic science concepts such that experts using them could readily
recognize whether the device was functioning properly; the major concern with respect to these
devices was assuring truthful labeling.”227 During the first 20 years following enactment of the
1938 law, FDA’s activity with respect to medical devices involved protecting the American
public from fraudulent devices; FDA began to turn its attention to the hazards from legitimate
devices around 1960.228
Congress amended the FFDCA in 1962 to require FDA approval of a new drug application prior
to marketing and to require that a new drug be shown to be effective as well as safe. Following
these changes, FDA began “to impose rigorous premarket approval of some products that today
would be deemed devices.” Court decisions in the late 1960s upheld FDA’s authority to regulate
some medical devices as drugs due in part to the overlapping definitions of drug and device in the
1938 law. FDA classified a number of devices as drugs (contact lenses, injectable silicone,
pregnancy-test kits, bone cement), and only such devices were subject to premarket review (prior
to 1976). However, the approach of classifying devices as a drug was unsuccessful in other court
decisions, and the need for more comprehensive authority to regulate devices was recognized by
the Kennedy, Johnson, and Nixon Administrations.229
The Medical Device Amendments of 1976
The Medical Device Amendments of 1976 (MDA; P.L. 94-295) was the first major legislation
passed to address the review of medical devices. The MDA provided a definition for the term

225 U.S. Congress, House Committee on Interstate and Foreign Commerce, Medical Device Amendments of 1976, to
accompany H.R. 11124, 94th Cong., 2nd sess., February 29, 1976, H. Rept. 94-853, p. 6.
226 Ibid. “A device is adulterated if it includes any filthy, putrid, or decomposed substance, or if it is prepared, packed,
or held under unsanitary conditions. A device is misbranded if its labeling is false or misleading; unless it identifies the
manufacturer, packer, or distributor and quantity of contents; if required labeling statements are not conspicuous; if it
fails to bear adequate directions for use or adequate warnings; or if it is dangerous to health when used as indicated.”
227 Ibid.
228 Ibid., p. 7.
229 U.S. Congress, House Committee on Interstate and Foreign Commerce, Medical Device Amendments of 1976, to
accompany H.R. 11124, 94th Cong., 2nd sess., February 29, 1976, H. Rept. 94-853, pp. 8-9.
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device.230 It established a number of requirements referred to as general controls that applied to
all devices.231 Examples include provisions on adulteration and misbranding, prohibitions on false
or misleading advertising, and a requirement to register all medical device manufacturers with
FDA. One such provision required manufacturers to notify FDA 90 days prior to the marketing of
any new device; if the agency failed to act, marketing could begin. Because this provision is
outlined in Section 510(k) of the FFDCA, it is often referred to as a “510(k) notification.”
The MDA directed FDA to classify, into one of three classes, all medical devices that were on the
market at the time of enactment; these are the preamendment devices.232 Congress provided
definitions for the three classes—class I, class II, class III—based on the risks to patients posed
by the devices. In contrast to the approach taken with pharmaceuticals (all, except generic agents,
undergo rigorous premarket review and approval), Congress limited premarket approval to only a
small number of devices. “Only the highest-risk category [class III] would require agency review
and approval as a precondition for commercial sale and routine medical use. The other two
categories would be subject not to a rigorous review but merely a requirement [510(k)] that the
manufacturer of a device notify FDA, at least 90 days before commencing marketing, of its intent
to distribute the product commercially.”233 For class I devices, no additional review was needed
once that status was confirmed; general controls were considered to be sufficient to protect public
health. For class II devices, limited supplemental review was needed to verify conformity with
performance standards if such standards had been established by the agency.234
Under MDA, all devices coming to market after enactment were automatically placed in class III
until reclassified; these are the postamendment devices. As stated above, class III medical devices
receive more intense scrutiny and require an application for premarket approval (PMA) before
they can be marketed. However, the MDA allowed for the reclassification of a device from one
class to another.
The MDA did not provide a definition for the term substantially equivalent. Nor did the MDA
itemize the required contents of a 510(k). Such a notification “need only set forth its proposed
intended use or indications for use, the device to which substantial equivalence is claimed, and
evidence demonstrating that equivalence.”235

230 “An instrument, apparatus, implement, machine, contrivance, implant, in vitro reagent, or other similar or related
article, including any component, part, or accessory, which is (1) recognized in the official National Formulary, or the
United States Pharmacopeia, or any supplement to them; (2) intended for use in the diagnosis of disease or other
conditions, or in the cure, mitigation, treatment, or prevention of disease, in man or other animals; or (3) intended to
affect the structure or any function of the body of man or other animals, and which does not achieve any of its principal
intended purposes through chemical action within or on the body of man or other animals and which is not dependent
upon being metabolized for the achievement of its primary intended purposes.” The definition was changed in 1992
from “any of its principal intended purposes” to “its primary intended purposes.” Current definition at FFDCA §201(h),
(21 U.S.C. §321(h)).
231 The law has since been amended to exempt many (class I) products from some general controls or to limit the
application of general controls to subsets of (class II or class III) products that pose higher risks. IOM, Medical Devices
and the Public’s Health: The FDA 510(k) Clearance Process at 35 Years
, Washington, DC, July 2011, p. 175.
232 Preamendment devices were presumed to be marketable. They did not undergo premarket review and could be
legally marketed unless FDA required their removal. After classifying the preamendment devices, FDA used them as
the first cadre of “predicate” devices in order to demonstrate substantial equivalence.
233 Ibid., p. 24.
234 Ibid., p. 177.
235 Ibid., p. 180.
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The Safe Medical Devices Act of 1990
The Safe Medical Devices Act of 1990 (SMDA; P.L. 101-629) made a number of changes to the
law, such as providing a definition for the term substantial equivalence and revising the definition
for class II devices. FDA had not promulgated performance standards for most class II devices.
The new law authorized the use of alternative restrictions, called special controls, at the agency’s
discretion and simplified the process of establishing performance standards for class II devices.
Examples of special controls include special labeling requirements, mandatory performance
standards, patient registries, and postmarket surveillance.
FDA also had experienced difficulty in promulgating regulations needed to require submission of
PMA applications for class III devices. SMDA authorized FDA to reconsider all the
preamendment devices that had been placed in class III and to reclassify some of these devices
into class I or class II.236 The purpose was “to reduce the number of device types that needed
PMA review.”237 For those devices remaining in class III, the agency was directed to establish a
schedule for promulgation of regulations calling for PMAs of devices that still used the 510(k)
notification as an entry to the marketplace.
SMDA established postmarket requirements for medical devices. It required facilities that use
medical devices to report to FDA any incident that suggested that a medical device could have
caused or contributed to the death, serious illness, or injury of a patient. Manufacturers of certain
permanently implanted devices were required to establish methods for tracking the patients who
received them and to conduct postmarket surveillance to identify adverse events. The act
authorized FDA to carry out certain enforcement actions, such as device product recalls, for
products that did not comply with the law.
The FDA Modernization Act of 1997
The Food and Drug Administration Modernization Act of 1997 (FDAMA; P.L. 105-115)
mandated wide-ranging reforms in the regulation of foods, drugs, and medical devices by FDA.
In general, provisions involving medical devices “were designed to reduce FDA’s workload and
permit concentration of resources on devices that presented greater potential for harm” and “to
limit the FDA’s discretion and authority in regulating the device industry” in order to “accelerate
the pace of technology transfer.”238
FDAMA eliminated the 510(k) notification requirement for most class I devices and some class II
devices. It authorized the creation of a third-party review system of 510(k) submissions for class I
and most class II devices that still required 510(k) review. It allowed certain new devices (those
not substantially equivalent to another device and automatically placed in class III) to be
evaluated for immediate placement in class I or class II.
For substantial equivalence determinations in which a new device has a different technological
characteristic, FDAMA requires that FDA “consider the least burdensome means of
demonstrating substantial equivalence and request information accordingly.”239 For a medical

236 FFDCA §515(i); 21 U.S.C. §360e.
237 IOM, Medical Devices and the Public’s Health: The FDA 510(k) Clearance Process at 35 Years, Washington, DC,
July 2011, p. 205.
238 Ibid., p. 213.
239 FFDCA §513(i)(1)(D); 21 U.S.C. §360c.
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device using an important breakthrough technology, or that does not have an approved alternative
device, priority review of the PMA must be provided by FDA.240
FDAMA limited the use of some postmarket controls (device tracking and postmarket
surveillance) to class II and class III devices, eased reporting requirements of adverse events for
device user facilities, eliminated mandatory reporting of adverse events by medical device
distributors, and directed FDA to establish a sentinel reporting system to collect information on
deaths and serious injuries or illnesses associated with the use of a medical device.241
Medical Device User Fee Acts of 2002
The Medical Device User Fee and Modernization Act of 2002 (MDUFMA; P.L. 107-250)
established a user fee program for specified premarket activities (e.g., review of premarket
submissions); user fees may not be used for other FDA or CDRH activities. MDUFMA also made
targeted changes that reduced regulatory burden and agency workload, such as allowing
establishment inspections to be conducted by accredited persons (third parties). MDUFMA was
amended and clarified by two laws—the Medical Device Technical Corrections Act of 2004
(MDTCA, P.L. 108-214) and the Medical Device User Fee Stabilization Act of 2005 (MDUFSA,
P.L. 109-43). MDUFSA made substantive changes to the MDUFA small business fee
waiver/reduction, specifically, expanding the applicability of the reduction in certain fees to more
businesses by modifying the definition of small business from those with gross receipts totaling
less than $30 million to those with gross receipts totaling less than $100 million (see Section
2(a)(3) and (4) of P.L. 109-43). The medical device user fee program established by MDUFMA
was subsequently reauthorized in 2007, 2012, 2017 and most recently in 2022.
FDA Amendments Act of 2007
The Food and Drug Administration Amendments Act of 2007 (FDAAA; P.L. 110-85) amended
the FFDCA and the PHSA to reauthorize the prescription drug and medical device user fee
programs and to make agency-wide changes, several of which had implications for the regulation
of medical devices. FDAAA created incentives, as well as reporting and safety requirements, for
manufacturers of medical devices for children; required that certain clinical trials for medical
devices and some other products be publicly registered and have their results posted; created
requirements to reduce conflicts of interest in advisory committees for medical devices and other
products;242 and made certain other amendments to the regulation of devices.
FDA Safety and Innovation Act of 2012
The Food and Drug Administration Safety and Innovation Act of 2012 (FDASIA, P.L. 112-144)
amended the FFDCA and the PHSA to reauthorize the prescription drug and medical device user
fee programs, create new user fee programs for generic and biosimilar drug approvals, and
modify FDA authority to regulate medical products. Several provisions in FDASIA modified
aspects of premarket and postmarket medical device regulation. Examples of premarket changes
include those that affect the efficiency, transparency, and data requirements of the 510(k) and
PMA processes, and alter or make clarifications to certain types of exempt devices; for example,

240 FFDCA §515(d)(5); 21 U.S.C. §360e.
241 FFDCA §519 and §522. A device user facility means a hospital, ambulatory surgical facility, nursing home, or
outpatient treatment facility that is not a physician’s office.
242 FDA uses advisory committees to gain independent advice from outside experts.
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custom devices and humanitarian use devices. Provisions affecting postmarket regulation include
those that focus on expanding active postmarket surveillance, altering requirements related to
postmarket studies for devices, and strengthening both device recall and tracking capabilities
through a recall program and the unique device identifier system. FDASIA also required the
Secretary to establish a program to improve the device recall system.243
Miscellaneous reforms include those aimed at increasing transparency of FDA’s approval and
clearance decisions and processes for issuing industry guidance documents, improving health
information technology for the agency, and harmonizing device regulation with FDA’s
international counterparts.
21st Century Cures Act
The 21st Century Cures Act (P.L. 114-255) was signed into law on December 13, 2016. Division A
of the law provides funding for biomedical research—including the Precision Medicine Initiative
(PMI) and the Cancer Moonshot Initiative—and for the opioid crisis response; modifies FDA
pathways for the approval of regulated medical products; and makes a number of reforms to the
National Institutes of Health (NIH). Certain provisions made changes to the regulation of medical
devices to enhance access to innovative devices and to streamline aspects of the medical device
review process.
Specifically, the law established the Breakthrough Device Designation to codify certain existing
agency efforts and to help speed access to innovative devices that “provide more effective
diagnosis or treatment of a life-threatening or irreversibly debilitating condition” and that
“represent breakthrough technologies for which no approved alternatives exist” without
compromising or altering the standards of review for the devices. In addition, the law expanded
the applicability of the HDE, ensuring that this exemption would apply to more devices affecting
more people.
Other changes included establishing a formal mechanism for requesting recognition of standards
that may be used for purposes of premarket review; requiring FDA to clarify class I and class II
devices that are exempt from 510(k) notification requirements; and ensuring that there is
“adequate expertise” on device classification panels. In addition, it provided flexibility for
Institutional Review Board (IRB) requirements related to Investigational Device Exemptions
(IDEs); ensured that each FDA employee involved in the review of premarket submissions,
including supervisors, receives training on the “meaning and implementation of the least
burdensome requirements,” and clarified that least burdensome principles should include the
effect of postmarket activities on premarket decisions; and modified the definition of medical
device
to exclude certain types of health software, including products that provide a variety of
administrative and health management functions, electronic health record technology, and
software that interprets and analyzes patient data to help make clinical diagnosis or treatment
decisions.
FDA Reauthorization Act of 2017
The Food and Drug Administration Reauthorization Act of 2017 (FDARA, P.L. 115-52) Title II,
the Medical Device User Fee Amendments of 2017, reauthorized the medical device user fee
program through FY2022. FDARA also made certain changes relevant to regulation of pediatric

243 FDASIA §605; FFDCA §518A; 21 U.S.C. §360h–1. Among other things, it required an assessment of information
on device recalls, an assessment of the effectiveness of corrections or action plans for recalls, and documentation of the
basis for terminations of recalls.
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devices specifically, including adding additional elements to the required annual report on
pediatric medical devices; reauthorizing funding for an FDA demonstration grant program for
improving pediatric medical devices, and requiring a nonprofit consortium that receives a
demonstration grant to provide regulatory consultation to device sponsors in support of a
pediatric device application; and requiring the Secretary to convene a public meeting on the
development, approval or clearance, and labeling of pediatric medical devices not later than one
year after enactment.
FDARA made a number of changes to improve the inspection process for device manufacturing
facilities. These included, among others, changing the inspection schedule of establishments
engaged in the manufacture or processing of a device from biennial to a risk-based approach;
requiring the Secretary to identify and adopt uniform standards and processes for the conduct of
device establishment inspections, other than for-cause inspections; adding that a device may be
considered to be adulterated if a device establishment delays, denies, or limits an inspection, or
refuses to permit entry or inspection; and allowing the Secretary to recognize a wider range of
auditing organizations to facilitate international device establishment inspections. In addition,
FDARA made changes to the classification of accessories that are used with medical devices;
directed the Secretary to initiate one or more voluntary postmarket pilot projects to generate
timely and reliable information on the safety and effectiveness of approved or cleared medical
devices (the pilot projects will use electronic health data and will prioritize certain specified
devices and device types); and required the Secretary, acting through the FDA Commissioner, to
conduct a review through an independent third-party contract to determine whether such pilot
projects generate reliable and timely evidence about the safety and effectiveness of medical
devices. Finally, FDARA made changes to the regulation of over-the-counter hearing aids and
required a report on medical device servicing.
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Appendix B. Acronyms Used in This Report
ADN
Annual Distribution Number
CBER
Center for Biologics Evaluation and Research
CDER
Center for Drug Evaluation and Research
CDRH
Center for Devices and Radiological Health
C.F.R.
Code of Federal Regulations
CGMP
Current Good Manufacturing Practice
eMDR
Electronic Medical Device Reporting
FDA
Food and Drug Administration
FDAAA
Food and Drug Administration Amendments Act of 2007
FDAMA
Food and Drug Administration Modernization Act of 1997
FDARA
Food and Drug Administration Reauthorization Act of 2017
FDASIA
Food and Drug Administration Safety and Innovation Act of 2012
FFDCA
Federal Food, Drug, and Cosmetic Act
GUDID
Global Unique Device Identification Database
HDE
Humanitarian Device Exemption
HHS
Department of Health and Human Services
HUD
Humanitarian Use Device
IDE
Investigational Device Exemption
IRB
Institutional Review Board
MAUDE
Manufacturer and User Facility Device Experience
MDA
Medical Device Amendments of 1976
MDR
Medical Device Reporting
MDUFA
Medical Device User Fee Amendments of 2017
NEST
National Evaluation System for Health Technology
NSE
Not Substantially Equivalent
OMB
Office of Management and Budget
OTC
Over-the-Counter
PAS
Post-Approval Study
PMA
Premarket Approval
QS
Quality System
RWD
Real-World Data
RWE
Real-World Evidence
SaMD
Software as a Medical Device
SE
Substantially Equivalent
SMDA
Safe Medical Devices Act of 1990
STeP
Safer Technologies Program
UDI
Unique Device Identification
U.S.C.
U.S. Code

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Author Information

Amanda K. Sarata

Specialist in Health Policy


Acknowledgments
Victoria Green, former Analyst in Health Policy, and Judith Johnson, former Specialist in Biomedical
Policy, contributed to earlier versions and drafts of this report.

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