What Are the Phases of Clinical Trials?

Clinical trials are scientific research studies that involve patients as subjects to test treatments and newly developed medicines. The research goes through several stages to make sure that the results are unarguably accurate and reliable. The first stage is usually done for a small group of around 20 to 80, where the subject therapy will be administered for the first time.

The second phase involves about a hundred to 300 patients. The results of the Phase I tests will be checked against and compared to the Phase II results. The study will only reach the third stage if the pre-determined number of patients benefit from the treatment. In Phase III, the respondents are a much larger group of a thousand to three thousand. This phase involves evaluation of the treatment's effectiveness and monitoring of its side-effects.

For a certain drug to pass the stringent standards of the Food and Drugs Administration, it should make it through the third phase. However, this isn't the last step; Phase IV trials will have to be conducted while the drug is already in the market.

The purpose of the fourth phase is to continually evaluate the effectiveness of the treatment or drug and to discover any new benefits that may come up from them. This is why it's common to hear about scientists “discovering new uses for X medicine or Y drug.” In the end, clinical trials assure you that your medication, barring all other factors, can give you the cure you need.