This research study is a Phase II clinical trial. Phase II clinical trials test the safety and effectiveness of an investigational intervention to learn whether the intervention works in treating a specific disease.~The FDA (the U.S. Food and Drug Administration) has not approved Obinutuzumab for prevention of chronic Graft-vs.-Host Disease (cGVHD), but it has been approved for other uses.~In this research study, the investigators are aiming to determine the effect of Obinutuzumab on the incidence of corticosteroid-requiring cGVHD after allogeneic Hematopoetic Cell Transplant (aHCT).~Chronic GVHD is a medical condition that can occur after bone marrow or stem cells are transplanted from one individual to another. After the transplant, the donor immune system may recognize the recipient body as foreign and may attempt to 'reject' the body. This process is referred to as Graft-vs. -Host Disease and may occur at any time, although generally not earlier than one hundred days after transplantation.~The immune system produces two types of lymphocytes (white blood cells), B cells and T cells. B cells are part of the 'memory' for the immune system, and they make antibodies (proteins) when bacteria, viruses or other potentially harmful materials enter the body. Obinutuzumab is an antibody, a molecule that targets certain cells by binding to specific parts of the target cell. In this case, Obinutuzumab will bind to a component of B cells called CD20, resulting in the B cell getting killed. It is thought that reducing the number of B cells will reduce the chances of developing cGVHD after transplant. Previous studies with another antibody targeting CD20 on B cells suggests that there may be a reduced chance of developing cGVHD and the need to prescribe Corticosteroids to treat cGVHD when B cells are killed.~This is a randomized, placebo controlled trial. This means that approximately half of the study participants will receive Obinutuzumab, and the other half will receive a placebo (saline solution). A computer will decide which participants will receive Obinutuzumab or placebo, and neither the participant or the study doctor will know which the participant has received until the study is completed. It is important to note that the current standard is to receive no therapy specifically to prevent cGVHD.
This research study is studying a drug called obinutuzumab as a means of preventing chronic Graft vs. Host Disease (cGVHD).