In food animal pharmacology, microbial resistance will continue to be a domi-
nant concern arising from antimicrobial drug use, although improved vaccines may
well better control the diseases they are currently used to treat. This would further
decrease market share and hence potentially the development of novel compounds.
The limited profitability of antimicrobial drugs is also a major consideration in
human medicine. Another likely advance is the emergence of non-hormonal growth
regulating technologies. Moreover, novel drugs approved in food animal species
will have short or even zero withdrawal times based on better SAR, whilst drug
delivery devices will be less invasive and have minimal impact on carcass quality or
safety. Tracking individual animals using implanted microchips may generate the
epidemiological databases that would facilitate control of drug resistance problems.
Implantation of biochemical sensors based either on nanotechnology or microflui-
dics together with wireless alert devices might permit sentinel monitoring of
specific genetic markers or metabolites of selected bacteria (e.g. enteropathogenic
E. coliH0157) or chemical exposures to prevent such animals from entering the
food supply.
Although such advances may be readily predicted from existing developments in
several newer technologies, the emergence of products with marketing authorisa-
tions will ultimately be critically dependent on regulatory acceptance of such novel
compounds and systems. History informs us that regulatory agencies have been
inflexible in adapting to new technologies; good examples being the difficulty of
replacing visual meat inspectors with specific microbial screening tests (National
Research Council 2001 ), or batch product testing with real-time individual-unit
product manufacturing technologies (e.g. Process Analytical technology (PAT))
(Rantanen 2007 ). One may therefore ask, how will combination products (for
example a novel drug in a computer controlled microfluidic device) be tested,
judged and approved? Differences in organisation and policy of regulatory agencies
across different jurisdictions regarding combination products are large. A similar
division occurs when food safety is handled under a different agency than com-
panion drug approval. Such agency structure may be deeply enshrined in tradition
and legal precedence, rendering major changes difficult even within a single country
and even more difficult globally. Likewise, the question can be put, will regulatory
agencies allow product development for specifically targeted populations. How
narrowly can such populations be defined and what will the data requirements be
for approval in subpopulations? Existing experiences in the United States with
minor species drug approvals suggest this area will not be easy to effect change.
Will regulatory agencies have the knowledge base and guidelines to regulate novel
products and their method of manufacture? For example, the definition of “nano” is
context specific with many existing formulations containing particles that might be
considered nano-size, yet they do not fit the strict material science definition of a
“true” nanomaterial , in which one dimension is less than 100 nm and the particle
has resulting unique physicochemical properties. Regulations designed to prevent
widespread environmental exposure and occupational exposure may inadvertently
raise the hurdle to the approval of a novel nanotherapeutic. As well as hurdles within
any one regulatory environment, there is uncertainty as to whether international
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