Preclinical development of a drug allows the prediction of its safety profile, as well as mechanisms of action. This enables the safety and toxicity to be predicted, providing information on whether it is a viable candidate for further study.
The target organs and tissues can be identified during preclinical development, with in vitro assays used to determine which organs are targeted. If heart tissue, for example, was also found to be a target of the drug, development may be paused due to the safety risk it could present.