Clinical trials usually progress through the following phases:
Phase I: Tests the safety, dosage, and side effects of a new intervention in a small group of healthy volunteers or patients. Phase II: Expands the study to a larger group to evaluate the intervention’s efficacy and further assess its safety. Phase III: Involves large-scale testing in different populations and settings to confirm efficacy, monitor side effects, and compare with standard treatments. Phase IV: Conducted after the intervention has been approved and marketed, focusing on long-term effects and real-world effectiveness.
