Phase 0

Not always used, phase 0 clinical trials are sometimes considered the bridge between preclinical research and phase 1 trials.

Duration: Varies, but usually less than one month

Participants: Phase 0 trials are conducted on a very small group of people, usually fewer than 15

Method: Participants are given a single microdose of the drug and are monitored to see how the body will react

Goal: The main goal is to observe how the body responds to, and processes the drug. Because the dose given is so low, phase 0 trials are not used to test the safety of dosage or if the drug will work. These trials can be used to determine which drugs show promise in terms of how the body processes them.