In order for a drug candidate under consideration for development to be eventually approved by the Food and Drug Administration (FDA) for human use, a series of Clinical Research Studies must be undertaken to demonstrate and adequately characterize the drug candidate’s effectiveness and side effects profile. This data package, once sufficiently compiled, will then be submitted to the FDA for their review and potential approval.
Generally, the clinical evaluation of a new drug progresses in stages.
The initial stage in the clinical development process is referred to as Phase-1. The main focus of Phase-1 studies is to determine whether the drug is safe for human consumption. An additional focus is to characterize how the drug candidate is metabolized by the human body. These types of studies are generally conducted in normal health individuals, and not in people suffering from the condition being considered for treatment. If the drug is determined to be safe for human consumption, the development progrm can advance to Phase-2
The second phase of clinical development is often referred to as hypothesis testing. It is during this phase of clinical evaluation that the question of whether the drug is actully effective in treating the condition under study is evaluated. The participants in this phase of clinical testing are people whoactually suffer from the disease in question, but are otherwise healthy. For example, in Joint Pain Research Studies, one of the questions being asked might be does the drug siginficantly reduce a key aspect of the underlying cause of the pain thatpeople with this type of condition frequently experience.
If there is sufficient confidentce that the drug under consideration for development does appear to do what it is intended to do, and continues to prove to be safe to take, the clinical research program may advance to Phase-3. Trials in this phase are generally referred to as “registrational” because these are the main trials that the FDA will focus on to determine whether the drug under consideration is acceptable for approval. These types of trials generally involve considerably more patients than were evaluated in Phase-2 trials, and to now allow patients to participate who are more representative of the types of people who would be eventually taking the medication, if it were approved. In other words, people who also suffer from an array of other co-morbid medical conditions.
The final stage of clinical development is Stage-4. These studies are conducted after a drug has already been approved. The purpose of these studies is to collect additional long-term data on the continued safety and effectiveness of the drug in question.