What is a clinical trial ?

Clinical trials are an integral part of clinical research and are at the heart of all medical advances. Clinical trials aim at developing new methods to prevent, detect and treat disease.

A clinical trial is a medical research conducted on humans in order to develop new treatments (vaccines, drugs, medical devices, surgical procedures) by assessing the safety, efficiency and/or other properties of an investigational product. Before being tested on humans, investigational products are evaluated first in the laboratory and then on animals (pre-clinical studies). This pre-clinical testing leads to the selection of the most promising products. Clinical trials are conceived to answer scientific questions while ensuring the safety of research subjects, and are conducted according to strict protocols. Investigational products follow several phases of clinical development before they reach the market. Clinical trials pertaining to each clinical phase have a distinct objective and aim at answering a specific question.

Phase I clinical trial:
Phase I clinical trials include all the initial tests of the investigational product on humans. The product is tested on a small group of volunteers (20-80 people). This first phase of clinical development aims at evaluating the safety of the product and its potential side effects.

Phase II clinical trial:
The experimental product is then administered to a larger group of volunteers (100-300 persons) to determine its efficacy and further evaluate its safety.

Phase III clinical trial:
Once the investigational product has successfully passed the first two clinical development phases, it is administered to a large group of volunteers (1000-3'000 people) in phase III. These large scale trials can confirm efficacy, monitor side effects and compare the product with a standard-of-care. Information on the most suitable use of the product is also collected.

Phase VI or post-marketing clinical trial:
A product that has received marketing authorization and is available to the general population will enter Phase IV of clinical development. During this phase the product is monitored on the long-term. Potential rare side effects and late complications may be identified in this manner.

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 Dernière mise à jour le 18/08/2021 à 15:27