OMEROS CORP

Omeros Corporation ( Omeros, the Company or we ) is an innovative, commercial-stage biotechnology company that discovers and develops first-in-class protein and small-molecule therapeutics for large-market and orphan indications, with particular emphasis on complement-mediated diseases, cancers, and addictive or compulsive disorders. Our complement-targeted product, product candidates, and therapeutic programs are primarily focused on diseases and disorders associated with the lectin and/or alternative pathways of complement. Our lectin pathway program includes inhibitors of mannan-binding lectin-associated serine protease 2 ( MASP-2 ) and our alternative pathway program includes inhibitors of mannan-binding lectin-associated serine protease 3 ( MASP-3 ). Our Commercial Product: YARTEMLEA (narsoplimab-wuug) YARTEMLEA (narsoplimab-wuug) is the first and only approved therapy for hematopoietic stem cell transplant-associated thrombotic microangiopathy ( TA-TMA ), an often-fatal complication of stem cell transplantation driven by activation of the lectin pathway of complement. YARTEMLEA selectively inhibits MASP-2, the effector enzyme of the lectin pathway, blocking the pathway’s activation while preserving classical and alternative complement functions important for host defense against infection. YARTEMLEA was approved by the U.S. Food and Drug Administration ( FDA ) on December 23, 2025 for the treatment of TA-TMA in adult and pediatric patients aged two years and older.