A key decision point on oncology drug development pathway is the proof of concept (POC) study. These POC studies need to provide information to the project teams to enable reasonable decision making about further developing a drug candidate. With increased costs of drug development, efficient studies for the POC study has become critical. However, resources allocated to POC are generally very limited and sample size are much smaller compared to confirmatory trial. Bayesian Approach can enhance the efficiency of the design and data analysis.