Clinical trials play an important role in the development of new treatment opportunities. Patients can decide voluntarily to take part in them. The studies are subject to a strict quality control plan in order to guarantee the safety of the participants.
To obtain an approval for a clinical trial of the European Medicines Agency (EMA) or the Food and Drug Administration (FDA), the results from the preclinical phase have to be known. Therefore, the scrutinizing substance is tested for possible dangerous effects in labs. After the drug is considered to be safe, it gets the permission for clinical trials. These are divided in three phases, where efficacy and safety of the investigating substance is evaluated in a large number of patients (more than 100 or 1000).
Clinical trials involving new drugs are commonly classified into several phases. Each phase of the drug approval process is treated as a separate clinical trial. The drug-development process will normally proceed through four phases over many years. If the drug successfully passes through the phases 1, 2 and 3 it will usually be approved by the national regulatory authority for use in the general population.
For more information about the background and processes of clinical trials, click the following: