Pembrolizumab Alone or With Idelalisib or Ibrutinib in Treating Patients With Relapsed or Refractory Chronic Lymphocytic Leukemia or Other Low-Grade B-Cell Non-Hodgkin Lymphomas

This phase II trial studies how well pembrolizumab alone or with idelalisib or ibrutinib works in treating patients with chronic lymphocytic leukemia or other low-grade B-cell non-Hodgkin lymphomas that have returned after a period of improvement (relapsed) or have not responded to treatment (refractory). Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Idelalisib and ibrutinib may stop the growth of cancer cells by blocking some of the enzymes needed for cell growth. Giving pembrolizumab alone or with idelalisib or ibrutinib may be an effective treatment in patients with chronic lymphocytic leukemia or other low-grade B-cell non-Hodgkin lymphomas.