Regulatory Challenges in Biomaterials: Focus on Medical Devices - Biomaterials Science: An Integrated Clinical and Engineering Approach - page 247

fast rate, perhaps an effect of the enormous pressure made by advo-
cates of patients, as well as to the economic interest of pharmaceuti-
cal companies in having a product that would fulfill the enormous
demand created by the increasing number of patients infected with
HIV. In addition, HIV protease inhibitors were developed by ratio-
nal computer design rather than by combinatory chemistry or high-
throughput screening, both time-consuming processes [44]. In
the case of medical devices, we have the case of highly innovative
and complex micro devices such as bio-micro-electro-mechanical
systems (BioMEMS), e.g., microchip drug-delivery systems, which
could take a considerable time for research and development (owing
to the several iterative cycles to optimize the device) before entering
a clinical phase and thereafter the market [45].
4) The control, or comparative, group : Many medical device trials use his-
torical controls instead of a placebo or the current best management
standards (BMS) as a comparative group. This could be attributed to
the fact that there are many problems in designing a control group
in device trials. An implantable device that needs a placebo surgery
against which it could be compared may not be ethically accepted.
The testing of some devices used to treat low-incidence diseases
where patient enrollment could be difficult to achieve would benefit
from using historical control groups. It could also become difficult
to provide a control group with an alternative device because such a
device might not exist.
5) The environment: The environment in which a trial is being run dif-
fers in drug and in medical device trials. Whereas medical device tri-
als are performed in highly specialized centers with highly trained
operators, drug trials are conducted through visits to the clinical
investigator office where the patient takes a simple pill, without
any inconvenience and without further need from any operator or
trained professional [37].
Table 10.3 sums up all the above regarding FDA pathways for the
approval of medical devices. We will describe a case study related to hip
replacement.
Challenges in Regulatory Approval of Medical Devices
In spite of the many efforts made by the FDA, many challenges remain to be
solved in the regulatory process of biomaterial medical devices. In the fol-
lowing section, we will describe some of these challenges that in the coming
years will demand innovative solutions.