A phase I trial is a first step in testing a new drug or treatment approach in people. It determines the drug’s safety, dosage, how patients tolerate it and whether the drug has side effects. This phase usually involves small groups of patients. If the phase I trial is successful, further clinical trials will study the effectiveness of the treatment.
A phase 2 trial tests the safe dosage of a drug or treatment on a larger group of patients. Researchers define side effects, learn how the drug is used in the body and discover how it helps the condition.
Phase 3 trials compare the new treatment to the current standard of care. Some participants receive the new drug while others receive the commonly used treatment. Researchers determine if the new treatment is better than, the same as or worse than a standard treatment. This phase may involve hundreds or even thousands of patients at multiple centers.
Phase 4 trials take place once the new treatment is approved for standard use and put on the market. We do not conduct phase 4 trials at The University of Kansas Cancer Center.