5 Pharmaceutics
Anthony W. Fox
5.1 Introduction
It is a triumph of modern pharmaceutics that most
of us do not give a thought to the difference
between a white powder and a tablet, and think
that ‘a drug is a drug is a drug’. This huge presump-
tion is doubtless because we do not, any more,
make pharmaceutical (or Gallenical) formulations
ourselves, and precious few of us have even
observed that complicated process. Nevertheless,
it is important to understand some elements of this
science because of the following:
Packaged white powders are probably not mar-
ketable, and overcoming Gallenical problems is
asine qua nonfor product success.
A suitable formulation permits the conduct of
clinical trials.
Formulations constrain clinical trial design.
Among other things, likely bioavailability must
be compared with toxicology coverage, well-
matched placebos may or may not be available,
and special procedures may be required (e.g.
masking colored intravenous infusions).Product storage and stability (or lack thereof)
can bias clinical trials results, and dictate shelf-
life in labeling.Formulation can strongly influence patient
acceptability and compliance.For all these reasons, and more, marketing and
clinical input on suitable formulations should be
included in the earliest considerations of project
feasibility, and it behooves the clinical researcher
to be able to provide such input in an informed
manner. Equally, we should understand the con-
straints, difficulties and regulatory ramifications
that all of our colleagues experience, including
those in the research pharmacy. At the end of the
day, product licences are awarded and NDAs are
approved typically after the resolution of at least as
many questions about ‘chemistry, manufacturing,
and controls’ (for which read ‘pharmaceutics’) as
about clinical efficacy and safety.Principles and Practice of Pharmaceutical Medicine, 2nd Edition Edited by L. D. Edwards, A. J. Fletcher, A. W. Fox and P. D. Stonier
#2007 John Wiley & Sons, Ltd ISBN: 978-0-470-09313-9