FLOW CYTOMETRY IN THE DRUG DEVELOPMENT PROCESS - Flow Cytometry in Drug Discovery and Development - page 66

PART II

FLOW CYTOMETRY IN THE DRUG
DEVELOPMENT PROCESS

V IRGINIA L ITWIN AND P HILIP M ARDER

The ultimate objective of the drug development process is to match a therapeutic need
with a safe and efficacious treatment.
The lifecycle of a new drug entity begins in research laboratories where disease
mechanisms are identified. In drug discovery laboratories, molecular targets for
disease intervention are established and target-specific screening assays developed.
Lead compounds then undergo comprehensive characterization followed by pre-
clinical toxicological assessment. Finally, a small percentage of compounds enters the
realmof clinical trials. The purpose of the clinical testing is to evaluate drug safety and
effectiveness after the compounds have been administered to healthy volunteers and/
or patient populations.
Flow cytometric methods are being employed at all stages of the drug development
process:

. In the earliest stages of drug discovery, multiparametric intracellular flow
cytometric analysis supports target identification. In addition, high-throughput
flow cytometry is used for compound screening so that potential compounds can
be selected from large libraries.
. During lead compound characterization, multiparametric analysis enables an
extensive investigation of the complex interrelated mechanisms of action.

In vitro and ex vivo flow methods employed in toxicology studies assist in
identifying and characterizing off-target effects at the single cell level.

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