Phase IV

Phase IV studies are conducted after the FDA has approved the drug for marketing and are referred to as post-marketing surveillance trials. These studies evaluate how well the treatment works over time in the general population and monitor for new adverse effects that occur over time or were not seen in earlier phases.

Other goals of Phase IV trials are to assess quality of life or cost effectiveness of the intervention.

Source: Types and Phases of Clinical Trials | What Are Clinical Trial Phases? (n.d.). American Cancer Society. Retrieved January 8, 2022, from https://www.cancer.org/treatment/treatments-and-side-effects/clinical-trials/what-you-need-to-know/phases-of-clinical-trials.html