The development of immuno-oncologic agents poses unique statistical challenges in study designs, data analyses and result interpretations. Discussion questions: (1)The use of combination therapies, for example combination with anti-CTLA-4 or anti-PD-L1, has become common in immuno-oncology clinical trials. How should we design a study to evaluate simultaneously the safety and efficacy of combination dose levels, and select the optimal combination dose? (2)Identifying an immune treatment which benefits a particular group of cancer subjects such as PD-L1+ subjects or PD-L1- subjects, is always critical in clinical development. How should we identify a biomarker and determine the cutoff for a continuous immune-related biomarker such PD-L1 to help with the strategic decision? (3)It has been observed that conventional RECIST criteria had limitation to evaluate the characteristics of immune-related tumor response. Several new sets of immune-related response criteria (irRC) have been introduced for efficacy evaluation in recent years. How should we implement the new criteria?