In vitro models represent an alternative technique to in vivo or ex vivo studies in the drug development process. Cell-based assays are used to measure the level of proliferation and toxicity, as well as activation of signalling pathways and changes in morphology in cultivated cells. The studies conducted in vitro are aimed to estimate the newly synthesised drugs’ ability to permeate biological barriers and exert their therapeutic or cytotoxic effects. However, more than half of all studied drugs fail in the second or third phase of clinical trials due to a lack of confirmed efficacy. About a third of drugs fail because of safety issues, such as unacceptable levels of toxicity. To reduce attrition level in drug development, it is crucial to consider the implementation of translational phenotypic assays as well as to decipher various molecular mechanisms of action for new molecular entities. In this review, we summarise the existing cell-based methods most frequently used in the studies on drugs, taking into account their advantages and drawbacks.
Running title: Cell-based approaches in drug development
