Clinical trials are a platform that takes up drugs, new medicines and devices from their idea stage to being available in the open market. Thousands of trials are underway almost every day across the world. They have helped to introduce numerous effective treatment methods and instruments and changed the history of medicines.
Here is a breakdown on the most commonly referenced phases of clinical trials:
Phase 0 is named for the beginning phase of human clinical trials. During the first test on humans, the treatment or drugs is applied to the patient with micro doses. A tiny amount of drug is given to a group of participating patients. The patients are then monitored and watched closely to determine if the expected effects are visible or not. The dose is usually minute to be therapeutic but is being tested to determine if the effects are being visible or not. It is designed to prove tolerability. This enables the researchers to test the viability for a large number of drugs and make decisions accordingly.
Phase 1 Trials are those in which a normal therapeutic dose is being administered to the human. There are several types of studies carried in this phase including the single ascending dose study, multiple ascending dose study and food effects study. In single ascending study, each patient is given similar doses and then the next group of patients get a higher dose. In a multiple ascending study, each patient is given multiple doses and then tested. Food effect study helps to determine the possible difference in effectiveness and absorption of drugs with or without food.
Phase II Trials start once the safety of the drug is verified from the previous phase. Larger groups of up to 300 patients are used in this phase and are intended to evaluate the efficacy of the treatment or drugs. The researchers continue to monitor the side effects, tolerability, and safety of the larger groups side by side.
In Phase IIA, evaluation of the most effective dose is made. In phase IIB, studies determine how well the medication works at this established dose.
Phase III trials usually start with the largest patient group of the any trial phases, usually numbered into thousands. They are designed such that it provides data on how well established efficacy works on the larger population. In order to provide information on the side effects and allowance of drugs, the current therapies are measured against performance.
Phase IV trials follow the Phase III and they include the process when the drugs ultimatelly reach the market. These studies help to monitor long term, unseen side effects and study the drugs in certain population groups that were earlier not included in original studies. The harmful side effects, if discovered in Phase IV, often lead the medication to be removed from the market.