Previous assignment to treatment during this study; subjects permanently withdrawn from study participation will not be allowed to re-enter study Previous assignment to treatment during this study. Subjects permanently withdrawn from study participation will not be allowed to re-enter study. Previous assignment to treatment during this study; subjects permanently withdrawn from study participation will not be allowed to re-enter study Previous assignment to treatment during this study; subjects permanently withdrawn from study participation will not be allowed to re-enter study Previous assignment to treatment during this study; subjects permanently withdrawn from study participation will not be allowed to re-enter study Previous assignment to treatment during this study; subjects permanently withdrawn from study participation will not be allowed to re-enter the study Previous assignment to treatment during this study; patients permanently withdrawn from study participation will not be allowed to re-enter the study REGORAFENIB EXCLUSION CRITERIA: Previous assignment to treatment during this study; patients permanently withdrawn from study participation will not be allowed to reenter Previous assignment to treatment during this study. Subjects permanently withdrawn from study participation will not be allowed to re-enter study. Patients who progress on placebo are specifically allowed to enroll on the treatment arm of the study if they meet all other entry criteria Previous assignment to treatment during this study; patients permanently withdrawn from study participation will not be allowed to re-enter the study Previous assignment to treatment during this study; subjects permanently withdrawn from study participation will not be allowed to re-enter study Previous assignment to treatment during this study; subjects permanently withdrawn from study participation will not be allowed to re-enter study Previous assignment to treatment during this study. Subjects permanently withdrawn from study participation will not be allowed to re-enter study. Previous assignment to treatment during this study; subjects permanently withdrawn from study participation will not be allowed to re-enter study Previous assignment to treatment during this study; subjects permanently withdrawn from study participation will not be allowed to re-enter study Previous assignment to treatment during this study. Subjects permanently withdrawn from study participation will not be allowed to re-enter study. Prior use of regorafenib; subjects permanently withdrawn from study participation will not be allowed to re-enter study Previous assignment to treatment during this study; subjects permanently withdrawn from study participation will not be allowed to re-enter study