Phase II in a clinical drug trial is done to assess:

Phase II in clinical drug trials conducted in larger groups of people than in that of Phase I trial group and it is done to study the drug kinetics and metabolism of a drug and to find the effectiveness, monitor the side effects, compare it to commonly used treatments and to collect information that will allow the drug or treatment to be used safely. Ref: Basic and Clinical Pharmacology By Katzung, 10th Edition, Pages 69-71; Goodman and Gilman's Manual of Pharmacology and Therapeutics, 10th Edition, Page 60