7. Patients who are <90 days post allogeneic stem cell transplant will be excluded. Patients beyond 90 days post-allogeneic stem cell transplant with active uncontrolled GVHD > grade 1 will be excluded. Patients who are on a stable dose of immunosuppressive therapy (tacrolimus, cyclosporine, or other) for > 2 weeks will be eligible but those with recent increase in the immunosuppressive medication dose within last 2 weeks to control GVHD will not be included. Note: Subjects may be using systemic corticosteroids or topical or inhaled corticosteroids post allogeneic stem cell transplant (inclusion based on post stem cell transplant activity and tolerability of checkpoint inhibitor by Matthew D, et al., ASH 2015 Annual Conference abstract # 860).