Hideharu Shintani
Biological products are mostly macromolecular entities that are considerably larger than most chemical
products. With the exception of synthetic oligonucleotides or peptides, living cells-complex metabolic factories
produce them. The target molecule(s) must be isolated from a biochemical milieu consisting of chemical entities
relatively similar to the desired product. As such, it may be difficult to completely eliminate impurities derived from
the host system. The purified target may comprise several structurally heterogeneous forms, some or all of which
might be active. Compared to traditional chemical drugs, biological materials are highly labile, and unable to tolerate
high temperatures or undue chemical or physical stress. Higher-order biological products (e.g., cells and tissues)
may have a very short window of viability. It requires numerous complex analytical methods to provide an effective
physiochemical profile of biotechnology products.
This paper has presented several factors to consider when selecting the analytical methods to assess the
identity, purity, impurities, concentration, potency, stability, and (in some cases) comparability of biotechnology
products. Since no single method can provide data on all key product parameters, orthogonal analytical methods
should be used to increase confidence in the quality of product. Methods used under good laboratory practice (GLP)
or CGMP quality practices must be validated for their intended use. The strategies for qualifying and/or validating
biomolecular methods should be based on the type of method, the nature of the product, and the parameter to be
evaluated with the data. Laboratories that adopt validated methods (e.g., compendial methods) must experimentally
verify the suitable performance of these methods in the user environment. In order to provide a complete product
development record, all of these activities must be adequately documented to demonstrate how, when, and by whom
they were conducted.
As has been noted, "Some data are worthless; some data are priceless. The conditions and procedures used to
find data ultimately determine their value". All decisions regarding the control of the process and the quality of the
product are based on data generated by analytical tests. If there are design flaws in the test methods, unrecognized
sources of method variation, or a method is chosen that cannot support the specification requirements, the data
will inevitably be inadequate, inaccurate, or unreliable. So, while it is certainly critical to understand the process by
which a biological or biotechnological product is produced, it is equally vital to understand the methods of analysis
that are applied to the product. Otherwise, it will be very difficult to distinguish between those data that are priceless
and those that are worthless.