What happens in a phase 1 clinical trial?

In a phase 1 clinical trial, researchers figure out whether a new treatment is safe. They look at what its side effects are, whether people can tolerate it, and the highest dose that people can tolerate. They also make sure the treatment affects the cancer.

Phase 1 trials are done in a small group of people, usually around 15 to 30.

Phase 1 is the first of four phases. Early phases (1 and 2) focus on safety, such as side effects and finding a safe dose. Later phases (3 and 4) compare the treatment to current standard treatments. Depending on the results of each phase, a treatment may move on to the next phase. Your healthcare team can explain what phase a trial is in and what that would mean for you.