For the development and future commercialization of a drug, there are three phases of clinical trials before the MA.
The phases of clinical trials on people are only started if the results of the animal testing upstream were found to be positive.
> Phase 1: We validate the tolerance.
It involves administering increasing amounts of the new molecule to healthy volunteers (under close surveillance) to evaluate the broad lines of product tolerance and pharmacological activity.
> Phase 2: Check the effectiveness and find the "right" dose.
This phase occurs in a small number of hospitalized patients. This is to verify that the benefit / tolerance ratio is favorable, and at least equivalent to the existing treatment without causing significant side effects. We try to establish the optimal dose, that is to say the one for which the therapeutic effect is the best with the least possible side effects.
> Phase 3: We do studies called "pivot".
In conditions as close as possible to the usual conditions of use of the treatments, the efficacy-tolerance ratio is checked on a large group of patients. Precautions for use are analyzed, and the risks of interactions with other products are identified. Trials can be performed in several hundred to several thousand patients.
Phase 4 applies after the MA (see interview), it concerns pharmacovigilance stricto sensu. It lasts as long as the drug remains on the market.
Clinical trials can be public or private. They are always taken on the initiative of a promoter and supervised by an investigator.
Promoter: the sponsor takes the initiative of the clinical research. It can be a drug company, a public research center, a health care facility ...
Investigator: The investigator is the person who directs and supervises the conduct of the clinical trial. In the majority of cases, it is a doctor.