Omeros Corporation announced positive results from a pre-specified interim analysis of its ongoing Phase 1b clinical trial of OMS906, the company's lead MASP-3 inhibitor, in complement-inhibitor-nave adults with paroxysmal nocturnal hemoglobinuria (PNH), a rare and life-threatening hemolytic blood disorder. Statistically significant and clinically meaningful improvements were observed in all measured markers of hemolysis, including hemoglobin (Hgb) and lactate dehydrogenase (LDH). OMS906 has been safe and well tolerated in this trial, consistent with Phase 1 safety observations in healthy subjects.

This single-arm, open-label clinical trial is evaluating the effect of once-monthly subcutaneous administration of OMS906 in patients with PNH. A total of 9 patients have been enrolled to date and all have been complement-inhibitor- treatment nave. achievement of once-quarterly dosing would be well received by physicians and their patients, representing a paradigm shift in the treatment of PNH and other alternative pathway disorders." Omeros' second OMS906 clinical trial in PNH patients, treating those who have demonstrated an inadequate response toravulizumab, a C5 inhibitor, just recently entered the OMS906 dosing phase and is ongoing.

The OMS906 clinical trial In C3 glomerulopathy is also underway. Preliminary data from both of these trials are expected in the third quarter of this year. Omeros is also preparing to initiate a clinical trial assessing once-quarterly systemic delivery of OMS906, avoiding the need for intravitreal delivery, in patients with geographic atrophy, an advanced form of dry age-related mac macular degeneration (AMD).

Omeros will present detailed clinical trial data, including data in this preliminary analysis, at an upcoming international conference. Omeros is also amending both of its ongoing Phase 1ss clinical trials in PNH to Phase 2, expanding enrollment, assessing planned higher doses, and making preparations to meet with regulatory authorities to discuss the clinical development plan to approval. About Omeros Corporation Omeros is an innovative biopharmaceutical company committed to discovering, developing and commercializing small- molecule and protein therapeutics for large-market and orphan indications targeting immunologic disorders including complement-mediated diseases, cancers, and addictive and compulsive disorders.

Omeros' lead MASP-2 inhibitor narsoplimab targets the lectin pathway of complement and is the subject of a biologics license application pending before FDA for the treatment of hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA). Narsoplimab is also in multiple late-stage clinical development programs focused on other complement-mediated disorders, including IgA nephropathy, COVID-19, and atypical hemolytic uremic syndrome. Omeros' long-acting MASP-2 inhibitor OMS1029 is currently in a Phase 1 clinical trial.

OMS906, Omeros' inhibitor of MASP-3, the key activator of the alternative pathway of complement, is advancing in clinical programs for paroxysmal nocturnal hemoglobinuria (PNH), complement 3 (C3) glomerulopathy and other related indications.