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Omeros Corporation's Phase 2 OMS721 Trial Resulting in Extended Access for Compassionate Use

- The Company Agrees to Physician Request to Continue Treatment of Patients with aHUS -

SEATTLE, Feb. 19, 2015 /PRNewswire/ -- Omeros Corporation (NASDAQ: OMER) today announced that it has completed dosing of the low-dose cohort of patients in its ongoing Phase 2 clinical trial evaluating the efficacy and safety of OMS721, the lead human monoclonal antibody for its mannan-binding lectin-associated serine protease-2 (MASP-2) program, in treating thrombotic microangiopathies (TMAs). TMAs are a family of rare, debilitating and life-threatening disorders characterized by excessive thrombi (clots) in the microcirculation of the body's organs, most commonly the kidney and brain. All patients in this study cohort received OMS721 and improvements were observed across TMA disease markers. The investigators treating all of these patients at different sites consider the improvements to be treatment-related and clinically meaningful. Based on observations in this cohort, a European investigator has requested that Omeros provide extended access to OMS721 for compassionate use in his two study patients, both of whom suffer from atypical hemolytic uremic syndrome (aHUS), a form of TMA.

In the clinical trial, the first cohort consisted of three patients treated with the lowest dose of OMS721. All three patients have aHUS. Platelet count, serum lactate dehydrogenase (LDH), and serum haptoglobin were measured as markers of disease activity. When compared to baseline levels, platelet counts improved in all patients. Serum LDH levels remained normal in one patient, substantially decreased to close to the normal range in another and remained elevated in the third. Haptoglobin improved in two patients, normalizing in one. Creatinine levels in the one patient with independent renal function also improved.

Under this program of extended access, the two patients treated by the investigator requesting compassionate use will continue to undergo current or higher dosing with OMS721. The third patient, treated at a site other than that of the requesting investigator, appeared clinically to no longer be in the acute phase of the disease after treatment with OMS721. The patient subsequently relapsed following cessation of OMS721 treatment. This patient was discontinued from the trial for precautionary reasons because of a serious adverse event – a localized inflammatory response often related to certain types of infections, one of which the patient previously had for three years while on immunosuppressive therapy. Such infections are associated with widely used TNF-alpha-targeting drugs. All data to date indicate no active infection in this patient. No other significant safety issues were observed in either this trial or in the previously completed Phase 1 program. Consistent with the Phase 2 trial protocol, a pre-planned data review by internal and external physicians resulted in a recommendation to proceed with the planned dose escalation to the mid-dose cohort.

Omeros has agreed to provide the requested access to OMS721 for compassionate use, subject to approval from the applicable European regulatory authority, which has indicated its interest in facilitating the request. Notification of the investigator's request for extended access was posted on, the U.S. government's publicly accessible clinical trial registry website. In response to interest generated by the posting, Omeros is issuing this press release to provide more detailed information.  

About Omeros' MASP-2 Program

Omeros 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 appears to be unique to, and required for the function of, one of the principal complement activation pathways, known as the lectin pathway. 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 the 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. Therefore, Omeros believes that it may be possible to deliver MASP-2 antibodies systemically and OMS721, its lead MASP-2 antibody, is designed to be self-administered by subcutaneous injection.

Omeros also believes that it has identified the proteins that activate 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 the development of antibodies that would block activation of the alternative pathway alone or in combination with the lectin pathway.

About Omeros Corporation

Omeros is a biopharmaceutical company committed to discovering, developing and commercializing small-molecule and protein therapeutics for large-market as well as orphan indications targeting inflammation, coagulopathies and disorders of the central nervous system. Derived from its proprietary PharmacoSurgery® platform, the company's first drug product, Omidria (phenylephrine and ketorolac injection) 1%/0.3%, has been approved by the FDA for use during cataract surgery or intraocular lens replacement (ILR) to maintain pupil size by preventing intraoperative miosis (pupil constriction) and to reduce postoperative ocular pain. Omeros is completing preparations for a planned U.S. product launch in early 2015. Omidria is currently under review for marketing approval by the European Medicines Agency. Omeros has six clinical-stage development programs focused on: complement-related thrombotic microangiopathies; Huntington's disease, schizophrenia, and cognitive impairment; addictive and compulsive disorders; and preventing problems associated with surgical procedures. In addition, Omeros has a proprietary GPCR platform, which is making available an unprecedented number of new GPCR drug targets and corresponding compounds to the pharmaceutical industry for drug development.

Forward-Looking Statements

This press release contains "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, which are subject to the "safe harbor" created by those sections for such statements. All statements other than statements of historical facts are forward-looking statements. Terms such as "anticipate," "believe," "could," "estimate," "expect," "goal," "intend," "may," "plan," "potential," "predict," "project," "should," "will," "would," and similar expressions and variations thereof are intended to identify forward-looking statements, but these terms are not the exclusive means of identifying such statements. 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, risks associated with Omeros' ability to begin U.S. commercial sales of Omidria (OMS302) in early 2015, Omeros' ability to obtain regulatory approval for its Marketing Authorization Application in the EU for the commercialization of Omidria, Omeros' unproven preclinical and clinical development activities, regulatory oversight, product commercialization, intellectual property claims, competitive developments, litigation, and 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 November 10, 2014. 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, even if new information becomes available in the future.


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SOURCE Omeros Corporation

Jennifer Cook Williams, Cook Williams Communications, Inc., Investor and Media Relations, 360.668.3701,