This is not to be confused with experiments done in vitro ("within the glass"), i.e., in a laboratory environment using test tubes, Petri dishes, etc.
Examples of investigations in vivo include: the pathogenesis of disease by comparing the effects of bacterial infection with the effects of purified bacterial toxins; the development of non-antibiotics, antiviral drugs, and new drugs generally; and new surgical procedures.
In vivo testing is often employed over in vitro because it is better suited for observing the overall effects of an experiment on a living subject.
This discovery of anthrax toxin through the use of in vivo experiments had a major impact on studies of the pathogenesis of infectious disease.
"[6] Studies on In vivo behavior, determined the formulations of set specific drugs and their habits in a Biorelevant (or Biological relevance) medium.