Biomedical Engineering Reference
In-Depth Information
industry is extremely large and diverse, and it is the
responsibility of the approximately 1000 employees
of the CDRH to oversee this impressive enterprise.
The CDRH is divided into eight offices, one of which
(the Office of Device Evaluation, or ODE) is
primarily responsible for reviewing and approving
devices prior to their market release. Although this
responsibility is the one that consumers are perhaps
most aware of, the CDRH performs several other
important roles in overseeing the medical device
industry, and a different office is responsible for each
one: monitoring devices already on the market
(Office of Surveillance and Biometrics); taking action
against firms that violate the law (Office of Compli-
ance); performing research and developing standard
methods of evaluation (Office of Science and Engi-
neering Laboratories); and educating professionals
and consumers on the safe use of devices (Office of
Communication, Education and Radiation Programs).
Although the FDA was first given authority over
medical devices by the Food, Drug and Cosmetic Act
of 1938 (described in more detail in the next section),
premarket approval (PMA) for devices was not
required until that law was amended in 1976. At that
time, lawmakers realized that there were already
thousands of medical devices on the market and that
requiring companies to seek “retroactive” approval
for those existing devices would not be feasible. They
also recognized the fact that devices span a wide
range of risk (e.g., from stethoscopes to heart valves)
and that the relatively limited resources of the FDA
would be best used by concentrating them on the
highest risk devices and spending less time on rela-
tively low-risk devices, or devices with a long history
of safe performance. As a result, the system for
premarket regulatory approval was set up with two
major but diverging pathways: a more rigorous set of
requirements (usually requiring clinical testing) for
newer, higher risk devices, and a different pathway
for lower risk devices that could be demonstrated to
be “substantially equivalent” to devices that were
already established on the market prior to 1976.
These pathways will be described in more detail in
the following sections.
products made from PEEK, there a number of
common misconceptions about the FDA that should
be addressed up front. To begin with, it is not true that
FDA has explicitly approved PEEK (or any other
material) for use in the body because the FDA does
not approve materials themselves. It is true that
several devices manufactured from PEEK have been
cleared or approved by the FDA (these will be
described further in Section 17.9). It is also true that
the most common type of device application, the
510(k) premarket notification, relies on the sponsor's
ability to demonstrate that their new device is
equivalent to an existing legally marketed device, and
therefore similarity of materials is one of the many
factors taken into account when determining that
equivalence. FDA reviewers, however, are often
asked if there is a website or document that lists all of
the “FDA-approved materials,” although no such list
exists in reality. All applications to the FDA are
specific to a device, defined by an intended use and
its technological characteristics, not a material alone.
To be even more precise, the FDA does not issue
blanket approvals for a device either, but only
a device paired with a specific set of indications for
use.
Indications for use
generally describes the use of
the device (e.g., “immobilization and stabilization of
the spine”) and patient population (e.g., “patients
with degenerative disc disease”), along with other
pertinent details of how the device will be marketed.
This distinction is very important because receiving
FDA approval only allows the manufacturer to
market their new device for that particular set of
indications, not for any other purposes. If a manu-
facturer wishes to begin marketing the same device
for a different purpose (known as
expanding the
indications
), a new submission to the FDA is usually
required. If a device is used for indications beyond
those that were stated in its original FDA submission,
this is known as “off-label use” (sometimes also
called “physician directed use”). Over the years,
there have been a number of high-profile legal cases
in which manufacturers and their sales representa-
tives have promoted off-label use, a practice that is
explicitly in violation of the law. Note that, in
contrast, physicians are not prevented by the FDA
from using a device “off-label,” as long as they are
not doing so as part of an investigational trial inten-
ded to support an FDA submission for a new labeling
change
[1]
. Off-label use by physicians is considered
“practice of medicine” and specifically does not fall
under the jurisdiction of the FDA regulation of
17.3 Common Misconceptions
About What the FDA Does
Because this chapter is specifically intended to
discuss the role of the FDA in regulating PEEK, or
