Drugs and biologics in the research pipeline must undergo stringent preclinical toxicology and safety assessments before use in a clinical trial. Most traditional preclinical toxicology screenings include testing in animal models in order to define toxicological and pharmacological parameters that are critical to determining appropriate dosing such as maximum tolerated dose (MTD).
Toxicology studies typically include clinical and pathological data but flow cytometry has become a valuable tool for evaluating the safety profile of immunomodulatory drugs and biologics. Consider these benefits of including flow cytometry-based assays in your preclinical toxicology and safety assessment.
Defining Immunomodulatory Effects:
Many drugs or biologics may impact immune function or hematopoiesis without otherwise causing acute toxicity. Flow cytometric analysis of different immune cell subsets can identify undesirable effects a candidate drug may have on the immune system, and this can be critical for determining if a candidate advances to a clinical trial.
Flow cytometric analysis can be used to identify a biomarker in peripheral blood that correlates with unfavorable pathological outcomes. Biomarkers on specific immune populations may be evidence of unfavorable pathologic responses caused by an experimental therapy.
Flow cytometry-based toxicological analysis can provide a broad picture of the immune response to an experimental biologic or drug. Insight into how different immune cell populations respond to an experimental therapy can provide critical mechanistic understanding and be valuable to determining if a therapy may trigger catastrophic immune reactions.
Flow cytometry-based assays can be a valuable part of any preclinical or toxicological screening. Many experimental therapies in the research pipeline currently are being developed specifically for their immunomodulatory effects, and flow cytometry-based assays are becoming essential to the assessment of these candidates.
 McFarland, D. and Harkins, K. R. (2010) Flow Cytometry in Preclinical Toxicology/Safety Assessment, in Flow Cytometry in Drug Discovery and Development (eds V. Litwin and P. Marder), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470910085.ch6