Study objectives
The primary objective is to determine the overall response rate for pembrolizumab given with QS RT. Secondary objectives are to determine the following: response rate at the target and nontarget lesions, durability of response at the target lesion, PFS, OS and tolerability of the combination of QS RT and pembrolizumab. The exploratory objectives are to evaluate the effect of QS on pembrolizumab-mediated immune activation and to determine possible mechanisms of any observed immunosensitizing effects of the proposed ICI plus QS RT treatment regimen.