Hematological malignancies are cancers that affect blood, bone marrow, and lymph nodes, and include leukemias and lymphomas. They are also referred to as blood cancers or liquid tumors. Hematological malignancies result from improper production, function, and proliferation of blood cell including lymphocytes. Depending on the specific disease and its severity, treatment of hematological malignancies may involve chemotherapy, radiotherapy, or bone marrow transplant.
miRagen’s lead program targets miR-155, a microRNA that has key roles in the differentiation, function and proliferation of blood and lymph cells. Therapeutic inhibition of miR-155 in lymphoma cells is believed to restore normal function and reduce the aberrant cell proliferation that is characteristic of cancerous cells. We are developing MRG-106, to treat patients who suffer from the mycosis fungicides (MF) form of cutaneous T-cell lymphoma (CTCL). MF is the most common form of CTCL. It generally affects the skin, often causing rash and sometimes disfiguring skin lesions and tumors that can progress internally over time.
In addition to MF, elevation of miR-155 has been associated with several other blood cancers and certain solid tumors. We believe there is a potential opportunity to develop a companion diagnostic that could detect and quantify levels of miR-155 in circulating blood or malignant cells. We believe this approach may then allow for the selection of patients with elevated miR-155 levels who may be more likely to benefit from MRG-106 treatment and allow the drug to be used selectively in multiple cancers. There are several types of cancer in which high levels of miR-155 have been discovered, including subsets of diffuse large B-cell lymphoma, acute myeloid leukemia, certain virally induced lymphomas such as HTLV-1 associated lymphoma and Burkitt’s Lymphoma, Down Syndrome-associated acute lymphocytic leukemia, and other types of cancer. We plan to evaluate additional types of lymphoma and leukemia in Phase 1 clinical trials and intend to explore other potential applications for MRG-106 through additional clinical studies in other tumor types.