Previous allogeneic bone marrow transplant Patients with previous allogeneic bone marrow transplant Has had a prior stem cell or bone marrow transplant. Has received an allogeneic bone marrow or allogeneic stem cell transplant. ELIGIBILITY CRITERIA FOR BONE MARROW TRANSPLANT EXCLUSION CRITERIA FOR BONE MARROW TRANSPLANT History of an allogeneic bone marrow transplant. Prior allogeneic bone marrow transplant. Participants who have received a previous allogeneic bone marrow transplant Suitable for imminent bone marrow transplant, or within weeks of one. Bone marrow transplant: patient must be:\r\n* >= months since allogeneic bone marrow transplant prior to registration\r\n* >= months since autologous bone marrow/stem cell prior to registration Autologous or allogeneic stem cell or bone marrow transplant within months prior to cycle day Participants who are within months of an allogeneic bone marrow transplant INCLUSION CRITERIA FOR STRATUM C: Patient must be:\r\n* >= weeks since autologous bone marrow/stem cell transplant prior to enrollment\r\n* >= years since allogeneic bone marrow transplant prior to enrollment with no evidence of active graft versus (vs.) host disease Previous bone marrow or stem cell transplant Clinically significant pulmonary dysfunction, active infection, prior allogeneic bone marrow transplant, active autoimmune disease Prior allogeneic bone marrow transplant within months of screening date We will exclude patients who are eligible for an allogeneic bone marrow transplant at the time of study enrollment; if an enrolled patient subsequently becomes eligible for transplant, they will not be prevented from proceeding to the appropriate clinical treatment indicated Prior allogeneic bone marrow- or stem cell-transplant FOR ALL PHASES (Ib AND II): History of having received an allogeneic bone marrow or organ transplant Previous allogeneic bone marrow transplant Prior allogeneic bone marrow transplant Prior bone marrow or stem cell transplant Post-transplant bone marrow blast count ? % confirmed by standard of care bone marrow biopsy performed post-transplant (at least days post-transplant). Have undergone a prior allogeneic bone marrow transplant (BMT) Prior stem cell or bone marrow transplant Prior allogeneic bone marrow/peripheral blood stem cell transplant History of organ allograft (allogeneic bone marrow or stem cell transplant) within months prior to first dose of study drug Prior bone marrow or stem cell transplant. Subject has undergone a bone marrow transplant Undergone an organ transplant(s) including allogeneic stem cell or bone marrow transplants Previous bone marrow or stem cell transplant Patients with secondary AML, and patients with a prior autologous and allogeneic bone marrow transplant are eligible Prior allogeneic bone marrow or stem cell transplant Prior allogeneic bone marrow or stem cell transplant Pregnancy at the time of bone marrow transplant (BMT) History of bone marrow transplant; Receipt of an allogeneic bone marrow or allogeneic stem cell transplant Patients who received an allogeneic bone marrow or allogeneic peripheral blood stem cell transplant less than months prior to initiation of study Prior bone marrow or stem cell transplant Has a transplanted organ or has undergone allogeneic bone marrow transplant Prior autologous or allogeneic bone marrow or stem cell transplant Prior allogeneic bone marrow transplant Patients with an organ transplant, including those that have received an allogeneic bone marrow transplant. History of having received an allogeneic bone marrow or organ transplant Participant is a candidate for a bone marrow or stem cell transplant within weeks after study enrollment. Relapsed and or refractory multiple myeloma after at least one prior line of therapy; there is no upper limit of prior lines of therapy; patients who are ineligible for stem cell transplantation are allowed; patients should have received at least one prior novel agent (immunomodulatory agents or proteasome inhibitors); patients eligible for bone marrow transplant must have undergone bone marrow transplant (BMT) prior to enrollment Previous allogeneic bone marrow transplant. Prior autologous or allogeneic bone marrow/peripheral blood stem cell transplant History of any organ or bone marrow transplant Patients with a history of bone marrow transplant within the previous two years The patient had a previous bone marrow or stem cell transplant Patients with a history of bone marrow transplant within the previous two years History of allogeneic bone marrow/stem cell transplant Autologous or allogeneic bone marrow transplant as second-line therapy. Not eligible for stem cell/bone marrow transplant or have refused stem cell/bone marrow transplant or have relapsed after autologous or allogeneic stem cell/bone marrow transplant Has had a prior stem cell or bone marrow transplant Prior bone marrow transplant Prior bone marrow or stem cell transplant; Autologous or allogeneic stem cell or bone marrow transplant within months prior to first dose of study drug. Has received an allogeneic bone marrow or allogeneic stem cell transplant. Recent bone marrow transplant Autologous or allogeneic stem cell or bone marrow transplant within months prior to first dose of study treatment. Eligible for allogeneic bone marrow transplant. No more than prior lines of systemic anti-cancer therapy and no prior bone marrow transplant or stem cell transplant within months of dosing, and no prior allogeneic transplant. Patients with a history of bone marrow transplant within the previous two years Patients eligible for bone marrow transplant, regardless of age Subjects who received an allogeneic bone marrow or allogeneic peripheral blood stem cell transplant All patients must be enrolled within hours of admission except patients in the bone marrow transplant arm who may be enrolled at the beginning or during their bone marrow transplant Patients receiving myeloablative chemotherapy in preparation for allogeneic or autologous bone marrow or stem cell transplant Previous bone marrow transplant Admission to the University of North Carolina (UNC) Hospital Bone Marrow Transplant Unit for allogeneic stem cell transplant History of bone marrow transplant No current or history of a hematologic malignancy is allowed, including subjects who have undergone a bone marrow transplant. Recipient of a stem cell or bone marrow transplant.