Pathology in Non-Clinical Drug Safety Assessment

Abstract The process of drug discovery and development is highly complex, demanding extraordinary scientific acumen as well as an understanding of the regulatory milieu. Veterinary pathologists in industry find themselves at the vanguard of this process, helping companies to bring innovative new therapies to patients in need. In this chapter we focus on the role of the toxicologic pathologist in understanding both the nature of drug efficacy, as well as the pathogenic mechanisms of drug toxicity, and the way in which both perspectives play into decisions to either develop or halt development of a potentially promising drug candidate. We review the role of the toxicologic pathologist in discovering and developing small molecules as well as some of the extraordinary variety of biotherapeutic agents, with their inherent challenges and often unexplored potentialities. Other issues such as reversibility or delayed toxicity, imaging, GLP regulations, and the use of some advanced scientific tools used by toxicologic pathologists developing pharmaceutical agents are discussed. In progressive companies, as well as regulatory agencies, toxicologic pathologists bring their expertise to bear across the entire drug discovery and development pipeline to improve our understanding of the advantages and potential liabilities of new therapies.