phase II

Definition of phase II clinical trial

phase II clinical trial

(fayz … KLIH-nih-kul TRY-ul)
A study that tests whether a new treatment works for a certain type of cancer or other disease (for example, whether it shrinks a tumor or improves blood test results). Phase II clinical trials may also provide more information about the safety of the new treatment and how the treatment affects the body. Also called phase 2 clinical trial.

Source: NCI Dictionary of Cancer Terms