- Within the durvalumab monotherapy arm (cohort 1), subjects will be enrolled in a 3+3 design starting at dose level 0 (Table 2). If < 1 out of 3 subjects experience DLT, dose level 0 will be declared the RP2D for durvalumab monotherapy. If 1 out of 3 subjects experience DLT, an additional 3 subjects will be enrolled at dose level 0. If < 2 out of 6 subjects experience DLT, dose level 0 will be declared the RP2D for durvalumab monotherapy. If > 2 out of 6 subjects experience DLT, a RP2D will not be established and the study will close.