This is a study to determine the clinical benefit (how well the drug works), safety and tolerability of combining varlilumab and atezolizumab. Phase l of the study will enroll patients with a number of tumor types; Phase ll will enroll only patients with renal cell carcinoma (RCC).

Many tumor cells, in contrast to normal cells, have been shown to require the amino acid glutamine to produce energy for growth and survival. To exploit the dependence of tumors on glutamine, CB-839, a potent and selective inhibitor of the first enzyme in glutamine utilization, glutaminase, will be tested in this Phase 1 study in patients with solid tumors.