The U.S. Food and Drug Administration (FDA) has granted orphan drug designation for Iomab-B, a radioimmunotherapeutic that conditions relapsed and refractory Acute Myeloid Leukemia (AML) patients for a Hematopoietic Stem Cell Transplant (HSCT), commonly referred to as a Bone Marrow Transplant (BMT). Iomab-B will soon begin a 150 patient, pivotal Phase 3 multicenter trial in relapsed and refractory AML patients over the age of 55.
Iomab-B is a radioimmunoconjugate consisting of BC8, a novel murine monoclonal antibody, and iodine-131 radioisotope. BC8 has been developed by the Fred Hutchinson Cancer Research Center to target CD45, a pan-leukocytic antigen widely expressed on white blood cells. This antigen makes BC8 potentially useful in targeting white blood cells in preparation for hematopoietic stem cell transplantation in a number of blood cancer indications, including acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL), Hodgkin’s disease (HD), Non-Hodgkin lymphomas (NHL) and multiple myeloma (MM). When labeled with radioactive isotopes, BC8 carries radioactivity directly to the site of cancerous growth and bone marrow while avoiding effects of radiation on most healthy tissues.
Sandesh Seth, Executive Chairman of Actinium Pharmaceuticals, the company developing Iomab-B said in a prepared statement, “We are pleased to have been granted orphan drug status by the FDA for Iomab-B, particularly ahead of its pivotal Phase 3 clinical trial. There has not been a new drug approved for relapsed and refractory AML patients over the age of 55 in decades and with Iomab-B being the only therapy of its kind, we are pleased to have achieved this important milestone. Orphan drug status for Iomab-B follows Actimab-A, which was granted the designation in November 2014. Orphan drug status provides Actinium with several development and financial incentives, including seven years of market exclusivity in the United States, if Iomab-B receives marketing approval and exemption from prescription drug user fees.”
The FDA, through its Office of Orphan Products Development (OOPD), grants orphan status to drugs and biologic products that are intended for the safe and effective treatment, diagnosis, or prevention of rare diseases or disorders that affect fewer than 200,000 people in the U.S. Orphan drug designation provides a drug developer with certain benefits and incentives, including a period of marketing exclusivity if regulatory approval is ultimately received for the designated indication; potential tax credits on U.S. clinical trials; eligibility for orphan drug grants; and waiver of certain administrative fees.