SEATTLE, Nov. 7, 2013 /PRNewswire/ -- Omeros Corporation (NASDAQ: OMER) today announced positive clinical data in a Phase 1 clinical trial of OMS721, the company's lead human monoclonal antibody targeting mannan-binding lectin-associated serine protease-2 (MASP-2), an important regulator of the lectin pathway of the immune system. Subcutaneous administration of OMS721 achieved a high degree of lectin pathway inhibition. The drug was well tolerated and no drug-related adverse events were observed. A Phase 2 clinical program to evaluate OMS721 in the treatment of thrombotic microangiopathies (TMAs), a family of disorders that occurs in the microcirculation of the body's organs, most commonly the kidney and brain, is expected to begin enrollment in early 2014. This Phase 1 trial is a placebo-controlled, double-blind, single-ascending-dose study to evaluate the safety, tolerability, pharmacodynamics and pharmacokinetics of OMS721 administered either intravenously or subcutaneously in healthy subjects. To date, four cohorts of subjects have received OMS721 or placebo by subcutaneous injection at increasing dose levels. OMS721 or placebo injections were well tolerated in all subjects. No clinically significant abnormalities on laboratory tests or electrocardiograms have been observed. At the highest subcutaneous dose administered to date, OMS721 achieved serum concentrations that resulted in a high degree of inhibition of lectin pathway activation. The serum concentrations seen in the Phase 1 subjects are similar to those associated with efficacy in animal models of diseases linked to the lectin pathway, including those of TMA and neovascular age-related macular degeneration (AMD), a leading cause of vision loss in individuals over 60 years of age. Earlier this year, Omeros reported positive data using OMS721 in a well-established model of TMA. The company also recently announced preclinical findings indicating that blockade of MASP-2 by OMS721 may provide a new treatment for AMD. Omeros controls the worldwide rights to MASP-2 and all therapeutics targeting MASP-2. MASP-2 is critical to the function of the lectin pathway, one of the principal components of the complement system, a key part of the immune response.