What are Phase 1 clinical trials?


Phase 1 trials (sometimes called early treatment trials) aim to test the safety of various doses of a new drug. This includes looking at the side effects of a drug – for example, does it make people feel bad, raise their blood pressure etc? Phase 1 trials involve only a small number of people, who are usually healthy volunteers. In exceptional cases, for instance in cancer or HIV, patients who are at a very advanced stage of the disease may participate.