In vitro research is the lowest level of evidence in the hierarchy, following animal research. Both methods are used in measuring the safety and effectiveness of new treatments for humans and animals. Animal research, also known as in vivo testing, involves using living animals for drug development, whereas in vitro research uses tissue or cells for the same purposes (Khan et al., 2018). For many years, regulators and scientists have sought alternative methods to animal testing to reduce or stop their use in research. In in vitro research, human or animal cells are taken, prepared in the laboratory, and used for drug development (Khan et al., 2018). Although both techniques aim at the same objective, their benefits and drawbacks are different.
While the debate on if in vitro methods should replace animal research continues, understanding the contrast between the two levels of evidence is critical. In vitro research methods are quicker and cheaper than animal testing. However, animal research is most effective when assessing the impact of drugs on the entire organism (Khan et al., 2018). In vitro research involving human cells is perceived as a better representative of how the drug would behave on humans than animal tests. Nevertheless, animal research must be done after the in vitro tests to ascertain the findings. In vitro studies have successfully identified properties such as carcinogenic and mutagenic effects and toxicity mechanisms (Khan et al., 2018). In addition, they provide more relevant and precise findings on these properties. The success of in vitro research relies on the belief that toxicity manifestations observed during animal tests begin with a small number of identifiable events (Movia et al., 2020). In vitro testing has succeeded where animal testing fails, such as in the oral contraceptive evaluation and dementia (Khan et al., 2018). Therefore, each of the evidence levels presents advantages and limitations that scientists can balance for optimum results.
References
Khan, A., Waqar, K., Shafique, A., Irfan, R., & Gul, A. (2018). In vitro and in vivo animal models: The engineering towards understanding human diseases and therapeutic interventions. In D. Barh & V. Azevedo (Eds.), Omics Technologies and Bio-Engineering (pp. 431-448). Academic Press.
Movia, D., Bruni-Favier, S., & Prina-Mello, A. (2020). In vitro alternatives to acute inhalation toxicity studies in animal models—A perspective. Frontiers in Bioengineering and Biotechnology, 8, 549. Web.