The Four Trial Categories




  • Preclinical studies – So-called in vitro methods implies laboratory studies of bacterial, animal or human cells. In vitro is latin for: “Within the glass”. The purpose is:                             Observe natural processes or manipulate processes within single cells or between cells                                                                                                                                       Learn about how a component (drug) influence the cells functioning
  • Animal studies –  Often, but not always, it is considered as necessary or useful to test a drug on animals before moving on to trials on humans. Animal trials can be done on small organisms like flies, small animals like mice and rats or bigger animals like pigs. The purpose is:  

                                Test safety of a drug in a living organism without risking to harm humans 

                                Measure efficacy and test dosing in a living organism without risking to harm humans 

  • Clinical trials – testing treatment on humans:
  • Phase I – These trials test an experimental treatment on a small group of people for the first time. The purpose is:

Assess the treatment’s safety

Find out what a safe range would be for dosage

Identify side effects

  •  Phase II -The treatment is given to a larger group of people to:

  Obtain preliminary data on the effectiveness of the treatment for a particular disease or condition

   Further assess the treatment’s safety

   Determine the best dose

  •  Phase III –  The treatment is given to even larger groups of people to:

Confirm its effectiveness

Monitor side effects

Compare it to commonly used treatments

Collect information that will allow the treatment to be used safely on the market

  •  Phase IV-

Done after the treatment is approved and is on the market

Gather information on things, like the best way to use a treatment, and the long-term benefits and risks