Regulatory Process for the Approval of Drugs

Before any drug can be prescribed Regulatory agencies such as the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) require evidence that a drug is safe and effective.  Once this has been established a manufacturer receives a license to make the drug available for the general medical community’s use. 

A drug that is being developed for a disease or condition is put through a series of tests and studies BEFORE it enters clinical studies.  “Clinical studies” refer to testing a drug in humans:  that is, in the clinic.  The term “preclinical” or “nonclinical” refers to research conducted in the lab before advancing to safety and efficacy studies in humans.  Once evidence that the drug holds promise for the treatment of humans is collected from preclinical studies, the manufacturer submits an Investigational New Drug Application (IND) with the FDA.

Clinical research typically occurs in phases: 
• Phase 1 studies are the first studies in humans and usually involve testing in healthy adult volunteers
• Phase 2 studies involve testing in patients with the disease of interest and collect information on the drug’s effectiveness as well as continuing to collect safety information
• Phase 3 studies involve more detailed testing on the drug’s safety and effectiveness in a larger study population
• Phase 4 studies would occur after approval of the drug and are used to evaluate safety and effectiveness in a larger group of patients and/or over a longer period of time

For some diseases including cancers and rare diseases, the first human studies may be done in patients with the disease and these are often called Phase 1/2 studies. 

After all required information has been collected from the preclinical and clinical studies, the manufacturer submits a Biologics License Application (BLA) or a New Drug Application (NDA) to the FDA for marketing approval.  (The process is similar in Europe but uses different terminology.)  The critical question for the FDA approval is whether the drug’s health benefits outweigh its known risks.