Omeros Announces Completion of Enrollment in OMS103HP Phase 3 Clinical Trial

-- On Track to Report Data Later this Year --

SEATTLE, Aug. 8, 2012 /PRNewswire/ -- Omeros Corporation (NASDAQ: OMER) today reported the completion of enrollment in the first of two planned Phase 3 clinical trials evaluating OMS103HP in patients undergoing arthroscopic partial meniscectomy surgery. OMS103HP is a proprietary drug product added to standard irrigation solutions and delivered to the operative site throughout arthroscopy to preemptively block the molecular-signaling and biochemical cascade caused by surgical trauma and to improve postoperative functional outcomes.

The Phase 3 clinical program for OMS103HP is assessing the drug's safety and efficacy in improving postoperative joint function and reducing pain following arthroscopic partial meniscectomy surgery. The program is expected to consist of two randomized, double-blind, vehicle-controlled, multicenter trials. The primary endpoint for both trials will be performance on the Knee Injury and Osteoarthritis Outcome Score (KOOS), a validated patient-reported outcomes measure used in Omeros' earlier successful Phase 2 meniscectomy trial.

The last patient enrolled in this Phase 3 clinical trial has undergone surgery and is now participating in the study protocol's postoperative evaluations. Omeros expects to be able to announce data from this trial during the second half of 2012 after those evaluations are complete. Assuming positive data from the current trial, Omeros plans to initiate enrollment in its second Phase 3 meniscectomy trial following discussions with European regulatory authorities.

"With this enrollment milestone achieved, we expect to announce data from three of our clinical programs during the remainder of 2012," said Gregory A. Demopulos, M.D., chairman and chief executive officer of Omeros. "In addition to wrapping up our Phase 3 OMS103HP trial, our other Phase 3 clinical program – OMS302 for lens replacement surgery – will complete its Phase 3 trial and, if the outcome is positive, we plan to submit both US and EU marketing applications in the first part of 2013. The Phase 1 clinical trial of our PDE10 inhibitor for cognitive disorders also remains on track for 2012 data, and we expect that one or more of our other pipeline programs will advance into the clinic next year."

Omeros' OMS103HP Program

OMS103HP is Omeros' PharmacoSurgery™ product candidate being developed for use during arthroscopic procedures, including partial meniscectomy surgery, and was designed to provide a multimodal approach to preemptively block the inflammatory cascade induced by arthroscopy. OMS103HP is a proprietary combination of anti-inflammatory/analgesic active pharmaceutical ingredients (APIs), each with well-known safety and pharmacologic profiles. Each of the APIs are components of generic, FDA-approved drugs that have been marketed in the United States as over-the-counter or prescription drug products for over 15 years and have established and well-characterized safety profiles.

In a Phase 2 clinical trial that evaluated OMS103HP in patients undergoing partial meniscectomy surgery, OMS103HP provided clinically meaningful and significantly greater efficacy than vehicle as measured by patient-reported functional scores using the Knee Injury and Osteoarthritis Outcome Score (KOOS), passive knee flexion and visual analog scale pain scores. The patient-reported outcomes measuring symptoms, pain, activities of daily living, sport and recreational activities and quality of life associated with the operated knee showed a sustained benefit through postoperative Day 90.

About Omeros Corporation

Omeros is a clinical-stage biopharmaceutical company committed to discovering, developing and commercializing products focused on inflammation, coagulopathies and disorders of the central nervous system. The Company's most clinically advanced potential products are derived from its proprietary PharmacoSurgery™ platform designed to improve clinical outcomes of patients undergoing a wide range of surgical and medical procedures. Omeros has four ongoing clinical development programs. Omeros may also have the near-term capability, through its GPCR program, to add a large number of new drug targets and their corresponding compounds to the market. Behind its clinical candidates and GPCR platform, Omeros is building a diverse pipeline of protein and small-molecule preclinical programs targeting inflammation, bleeding and central nervous system disorders.

Forward-Looking Statements

This press release contains forward-looking statements as defined within the Private Securities Litigation Reform Act of 1995, which are subject to the "safe harbor" created by those sections. These statements include, but are not limited to, statements regarding the following expectations of Omeros: the potential clinical benefits of OMS103HP; that Omeros will be able to announce clinical data this year from its OMS302, OMS103HP and PDE10 programs; that Omeros will initiate the second Phase 3 clinical trial of OMS103HP following discussions with European regulatory authorities; that it will file US and EU marketing applications for OMS302 during the first part of 2013; that one or more additional programs will enter the clinic in 2013; and that it will be able to unlock orphan GPCRs and add a large number of new drug targets and their corresponding compounds to the market. Forward-looking statements are based on management's beliefs and assumptions and on information available to management only as of the date of this press release. Omeros' actual results could differ materially from those anticipated in these forward-looking statements for many reasons, including, without limitation, the risks, uncertainties and other factors described under the heading "Risk Factors" in the Company's Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on August 7, 2012. Given these risks, uncertainties and other factors, you should not place undue reliance on these forward-looking statements, and the Company assumes no obligation to update these forward-looking statements publicly, even if new information becomes available in the future.

SOURCE Omeros Corporation