Phase III is a critical stage in the clinical trial process for new drugs or treatments. During this phase, researchers test the effectiveness and safety of a treatment on a larger group of participants, often involving thousands of people. This helps to gather more comprehensive data about how the treatment works in diverse populations and under various conditions. The results from Phase III trials are essential for regulatory approval. If the treatment proves to be effective and safe, the data is submitted to regulatory agencies like the U.S. Food and Drug Administration (FDA) for review. Successful completion of this phase can lead to the treatment being made available to the public.