Each stage of a clinical trial has its own purpose of ensuring that a treatment is safe and effective for public use, Phase 1 clinical trial. Clinical trials follow a typical series ranging from initial small-scale phase 1 studies to large-scale late-stage phase 3 studies. Phase 1 studies are closely monitored and collect information about how a drug interacts with the human body. Researchers adjust dosing schedules based on animal data to find out how much drug the body can tolerate and what its acute side effects are.
As the phase 1 trial continues, researchers answer research questions related to how it works in the body, the side effects associated with increasing the dose, and early information on the effectiveness of drug administration in limiting risks and maximizing potential benefits. This is important for the design of phase 2 studies. Phase 3 studies provide the majority of safety data. In previous studies, less common side effects may not have been detected.
Because these studies are longer and longer lasting, results are more likely to show rare or long-term side effects. At this stage of the FDA clinical trials, your product has received FDA approval and your marketing campaigns are underway. Answering these questions, while giving as few people as possible an unknown treatment, often requires several clinical trials in different “phases”. As in other trials, patients in phase III clinical trials are closely monitored for side effects and treatment is stopped if they are too difficult to manage.
They are willing to see if they can help others, and possibly themselves, by participating in a phase I clinical trial. But does this mean that sufferers are more likely to live longer? Are there rare side effects that have not yet been observed or side effects that only appear after a person has taken the medication for a long time? Answering these types of questions can take many more years and are often addressed in phase IV clinical trials. Treatments that have been shown to work in phase II clinical trials must be successful in one more phase before they are approved for general use. The FDA may withdraw approval of a drug if new research shows that it is not as safe or effective as previous tests have shown.
All new treatments must undergo clinical trials before being approved by the Food and Drug Administration (FDA). In a phase IV clinical trial, doctors may study the drug or treatment in different doses or with other drugs or treatments. For example, a drug may get FDA approval because it has been shown to reduce the risk of cancer recurrence after treatment. Although there are clinical trials for devices, as well as for other diseases and treatments, drugs for cancer patients are used in the example phases of clinical trials described here.
Knowing the phase of the clinical trial is important because it can give you an idea of how much is known about the treatment being studied. Phase III clinical trials compare the safety and effectiveness of the new treatment with the current standard treatment. If doctors believe the treatment is safe, it will be studied in a phase II trial.