Study | Description |
---|---|
Observational study | A study where researchers are learning about HIV/AIDS without actually testing a drug or other intervention. Such a study might involve drawing blood from trial participants over time, to understand characteristics of non-infected individuals and to observe what happens at the cellular level when they become infected. |
Pre-clinical trials | Studies of vaccines or treatment which are carried out in animals. |
Clinical trials | |
Phase I | Researchers test a vaccine in a small group of people (20–80) to determine how a drug should be given, how many doses are needed, and whether it is safe |
Phase II | Experimental vaccine is given to a larger group of people (100–300) to see if it is effective and to further evaluate its safety |
Phase III | Experimental vaccine is given to large groups of people (1,000-3,000) to confirm its effectiveness, monitor side effects, and compare to commonly used treatments. |
Phase IV | Post-marketing studies determine a drug’s risks, benefits, and optimal use. |