Blastic Plasmacytoid Dendritic Cell Neoplasm

This research study is studying a drug as a possible treatment for diagnosis of AML, BPDCN and high-risk MDS. The interventions involved in this study are: * SL-401 * Azacitidine * Venetoclax

CP-MGD024-01 is a Phase 1, open-label, multi-center study of MGD024 as a single agent in participants with select blood cancers that have not responded to treatment with standard therapies or who have relapsed after treatment. The study is designed to determine the safety, tolerability, pharmacokinetics (affect of the body on the drug), pharmacodynamic (affect of the drug on the body), immunogenicity (development of antibodies against the drug), and preliminary anti-cancer effect of MGD024. Participants will receive treatment with MGD024 in consecutive 28-day cycles for a study treatment period of up to 12 cycles (approximately 1 year) or until treatment or study discontinuation criteria are met. Response assessments will be performed after Cycle 1 and then after every even numbered cycle starting with Cycle 2 until progression or study treatment discontinuation. Participants will be checked for side effects throughout the study.

This phase II trial studies how well naive T-cell depletion works in preventing chronic graft-versus-host disease in children and young adults with blood cancers undergoing donor stem cell transplant. Sometimes the transplanted white blood cells from a donor attack the body's normal tissues (called graft versus host disease). Removing a particular type of T cell (naive T cells) from the donor cells before the transplant may stop this from happening.

This phase II trial studies how well venetoclax, SL-401, and chemotherapy works in treating patients with blastic plasmacytoid dendritic cell neoplasm. Venetoclax may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. SL-401 is a recombinant protein consisting of IL-3 linked to a toxic agent called DT. IL-3 attaches to IL-3 receptors on tumor cells in a targeted way and delivers DT to kill them. Drugs used in chemotherapy work in different ways to stop the growth of tumor cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Giving venetoclax and SL-401 with chemotherapy may be an effective treatment for patients with blastic plasmacytoid dendritic cell neoplasm.

This phase II trial studies how well giving an umbilical cord blood transplant together with cyclophosphamide, fludarabine, and total-body irradiation (TBI) works in treating patients with hematologic diseases. Giving chemotherapy, such as cyclophosphamide, fludarabine and thiotepa, and TBI before a donor cord blood transplant (CBT) helps stop the growth of cancer and abnormal cells and helps stop the patient's immune system from rejecting the donor's stem cells. When the healthy stem cells from a donor are infused into the patient they may help the patient's bone marrow make stem cells, red blood cells, white blood cells, and platelets. Sometimes the transplanted cells from a donor can make an immune response against the body's normal cells. Giving cyclosporine and mycophenolate mofetil after transplant may stop this from happening in patients with high-risk hematologic diseases.