Cancer handbook: How clinical trials are run
For more information on clinical trials, please see our clinical trials page on our Kids Research website.
There are three phases or parts to a clinical trial. These are usually completed one after the other.
Phase 1
Investigates the side effects of a new drug and determines the optimal dose of that drug
Phase 2
Studies the activity the new drug has against individual tumour types
Phase 3
Determines how effective the new drug is compared to standard therapy