The process of learning about and developing an investigational medicine is divided into four phases. At first, very few people receive the medicine being studied. The number of people participating in clinical studies grows along with our understanding of the investigational medicine, and the research continues as long as the potential benefits outweigh the risks.
Trial Phases As a participant in a Phase 1 clinical trial, you’ll help researchers to understand the safety of an investigational medicine. You may have frequent clinical exams and lab work and will be asked to report any issues or side effects. These studies are often called “first in human.” TO SEVERAL MONTHS 1 TO By joining a Phase 2 clinical trial, you’re helping researchers determine effective dosages of the investigational medicine, along with its side effects and risk factors. Even after medicines are approved for use, you can continue to participate in long-term clinical studies designed to better understand the risks and potential benefits of the approved medicine over time. These clinical trials are often called “open-label studies.” PHASE 3 In a phase 3 clinical trial, you’ll be part of a larger group of people from around the world with the disease being studied. Your participation gives researchers a clearer understanding of the investigational medicine’s side effects and the potential effectiveness. PHASE 1 4 YEARS OVER A YEAR UP TO 2 YEARS 1 WEEK PHASE 2 PHASE 4 20 TO 100 PARTICIPANTS AS MANY AS SEVERAL HUNDRED PARTICIPANTS SEVERAL HUNDRED TO A THOUSAND PARTICIPANTS SEVERAL THOUSAND PEOPLE