Omeros Identifies Orphan GPCR-Targeting Compound Potentiating Chemotherapeutic Activity

SEATTLE, Nov. 9, 2010 /PRNewswire/ -- Omeros Corporation (Nasdaq: OMER), a biopharmaceutical company committed to discovering, developing and commercializing products focused on inflammation and disorders of the central nervous system, today announced that a compound identified by the Company as an antagonist of GPR87, an orphan GPCR recently unlocked for drug development by Omeros and linked to squamous cell carcinoma, potentiates the tumor-killing activity of doxorubicin (Adriamycin), a widely used chemotherapeutic agent. This is the first compound in a series of GPR87 antagonists exclusively identified by Omeros that the Company has evaluated in proof-of-concept models. Omeros is currently initiating medicinal-chemistry optimization of the compound.

Adriamycin is a potent chemotherapy drug commonly used to treat leukemias and Hodgkin's lymphoma, as well as cancers of the breast, lung, stomach, bladder, ovaries and thyroid, soft tissue sarcoma, multiple myeloma, and other types of cancer. While very effective in killing cancer cells, Adriamycin's dosing is limited by its life-threatening damage to heart muscle. The ability to reduce Adriamycin's dosing and its dose-related toxicity, while maintaining its cancer lethality, would be a significant advance in the treatment of multiple types of cancer.

"We are excited by these recent data further confirming that our Cellular Redistribution Assay identifies compounds that interact with orphan GPCRs and affect their function," said Gregory A. Demopulos, M.D., chairman and chief executive officer of Omeros. "Despite not yet having optimized this GPR87 antagonist, the compound demonstrates the expected benefit of potentiating tumor-cell killing by Adriamycin. We are eager to evaluate our other GPR87 antagonists, as well as the compounds that we identified as antagonists of GPR85 and GPR101, and look forward to screening the remaining orphans."

Ongoing GPCR Program

Omeros has begun screening orphan GPCRs against its small-molecule chemical libraries using a proprietary, high-throughput assay. Based on the limited screening of libraries to date, Omeros has already identified and confirmed sets of compounds that interact selectively with, and modulate signaling of, three of these orphan receptors linked to cancer (GPR87), obesity (GPR85) and appetite control (GPR101). The assay detects receptor antagonists and agonists. Antagonists comprise the majority of marketed drugs, and all of the compounds identified so far by Omeros are antagonists.

About G Protein-Coupled Receptors

GPCRs, which mediate key physiological processes in the body, are one of the most valuable families of drug targets. Annual worldwide drug sales exceed $700 billion and, according to Insight Pharma Reports, GPCR-targeting drugs represent 30 to 40 percent of marketed pharmaceuticals. Examples include Claritin® (allergy), Zantac® (ulcers and reflux), OxyContin® (pain), Lopressor® (high blood pressure), Imitrex® (migraine headache), Reglan® (nausea) and Abilify® (schizophrenia, bipolar disease and depression) as well as all other antihistamines, opioids, alpha and beta blockers, serotonergics and dopaminergics.  

The industry focuses its GPCR drug discovery efforts mostly on non-sensory GPCRs. Of the 363 total non-sensory GPCRs, approximately 240 have known ligands (molecules that bind the receptors) with nearly half of those targeted either by marketed drugs (46 GPCRs) or by drugs in development (about 70 GPCRs). There are approximately 123 GPCRs with no known ligands, which are termed "orphan GPCRs." Without a known ligand, drug development for a given receptor is extremely difficult.

Omeros uses a proprietary high-throughput assay to identify small-molecule agonists and antagonists for orphan GPCRs, unlocking them to drug development. Omeros believes that it is the first to possess the capability to unlock orphan GPCRs in high-throughput, and that currently there is no other comparable technology. The Company believes that there may be more than 60 new drugable targets among the orphan GPCRs. Unlocking these receptors could lead to the development of drugs that act at these new targets. There is a broad range of indications linked to orphan GPCRs including cardiovascular disease, asthma, diabetes, pain, obesity, Alzheimer's disease, Parkinson's disease, multiple sclerosis, schizophrenia, learning and cognitive disorders, autism, osteoporosis, osteoarthritis and several forms of cancer.

About Omeros Corporation

Omeros is a clinical-stage biopharmaceutical company committed to discovering, developing and commercializing products focused on inflammation and disorders of the central nervous system. The Company's most clinically advanced product candidates 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 five ongoing clinical development programs, including four from its PharmacoSurgery™ platform, the most advanced of which is in a Phase 3 clinical program, and one from its Addiction program. Omeros may also have the near-term capability, through its GPCR program, to add wholly new drug targets to the market. Behind its clinical candidates and GPCR platform, Omeros is building a diverse pipeline of antibody and small-molecule preclinical programs targeting inflammation 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. 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 and include the Company's capability to continue high-throughput de-orphanization of orphan GPCRs and to develop product candidates that act at these new potential drug targets, the ability of GPR87-targeting compounds to reduce Adriamycin's dosing and its dose-related toxicity while maintaining its cancer lethality, the potential market size for GPCR-targeting drugs and the number of new drugable targets that are estimated to exist among the orphan GPCRs. 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 November 4, 2010. 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