Omeros Corporation (NASDAQ: OMER) today announced that it has filed an application for orphan drug designation with the U.S. Food and Drug Administration (FDA) for OMS721 in the treatment of immunoglobulin A (IgA) nephropathy (also known as Berger's disease). IgA nephropathy leads to end-stage renal disease in up to 40 percent of patients. Orphan drug designation is granted to treatments that target conditions affecting 200,000 or fewer U.S. patients per year. Orphan-designated drugs are eligible for financial incentives and regulatory advantages such as a faster approval process and additional market exclusivity. OMS721 is Omeros' lead human monoclonal antibody targeting mannan-binding lectin-associated serine protease-2 (MASP-2), the effector enzyme of the lectin pathway of the complement system. FDA earlier granted orphan designation for OMS721 in thrombotic microangiopathies (TMAs), including atypical hemolytic uremic syndrome (aHUS) and hematopoietic stem cell-associated TMA (HSCT-TMA). Based on positive Phase 2 data in renal diseases, Omeros also recently filed for FDA fast track designation for OMS721 in IgA nephropathy. The company already has received fast track designation for OMS721 in aHUS. In addition to positive Phase 2 data in IgA and membranous nephropathies, Omeros has reported positive data from Phase 2 clinical trials in both aHUS and HSCT-TMA. Following guidance from FDA and from the European Medicines Agency, Omeros plans to open enrollment for its single Phase 3 trial in patients with aHUS later this year. Based on discussions with the FDA, the company is pursuing breakthrough therapy designation for OMS721 in IgA nephropathy and in HSCT-TMA, neither of which has any approved treatment. Omeros plans to initiate OMS721 Phase 3 programs in both IgA nephropathy and HSCT-TMA next year. About Orphan Drug StatusOrphan drug designation is granted by the FDA's Office of Orphan Products Development for treatments that are expected to provide significant therapeutic advantage over existing treatments and that target conditions affecting 200,000 or fewer U.S. patients per year. Orphan drug designation qualifies a company for several benefits under the Orphan Drug Act of 1983. The benefits apply across all stages of drug development and include accelerated approval process; seven years of market exclusivity following marketing approval; tax credits on U.S. clinical trials; eligibility for orphan drug grants; and waiver of certain administrative fees. About Omeros' MASP-2 ProgramOmeros controls the worldwide rights to MASP-2 and all therapeutics targeting MASP-2, a novel pro-inflammatory protein target involved in activation of the complement system, which is an important component of the immune system. The complement system plays a role in the inflammatory response and becomes activated as a result of tissue damage or microbial infection. MASP-2 is the effector enzyme of the lectin pathway, one of the principal complement activation pathways. Importantly, inhibition of MASP-2 does not appear to interfere with the antibody-dependent classical complement activation pathway, which is a critical component of the acquired immune response to infection, and its abnormal function is associated with a wide range of autoimmune disorders. MASP-2 is generated by the liver and is then released into circulation. Adult humans who are genetically deficient in one of the proteins that activate MASP-2 do not appear to be detrimentally affected by the deficiency. Omeros has received both Orphan Drug status and fast track designation from the U.S. FDA for its lead human MASP-2 antibody OMS721. Following discussions with both the FDA and the European Medicines Agency, a Phase 3 program for OMS721 in atypical hemolytic uremic syndrome is in progress. Also, two Phase 2 trials are ongoing with one evaluating OMS721 in glomerulonephropathies, which has generated positive data in patients with immunoglobulin A (IgA) nephropathy and with membranous nephropathy, and the other in thrombotic microangiopathies (TMAs), with positive data reported in patients with hematopoietic stem cell transplant-associated TMA. In addition to potential intravenous administration, Omeros plans to commercialize OMS721 for one or more therapeutic indications as a subcutaneous injection and is also developing small-molecule inhibitors of MASP-2. Based on requests from treating physicians, Omeros has established a compassionate-use program for OMS721, which is active in both the U.S. and Europe. Omeros also has identified MASP-3 as the protein that is critical to the activation of the complement system's alternative pathway in humans, which is linked to a wide range of immune-related disorders. In addition to its lectin pathway inhibitors, the company is advancing its development of antibodies and small-molecule inhibitors against MASP-3 to block activation of the alternative pathway.