Omeros' PDE7 program expands addiction franchise

Omeros Corporation (NASDAQ: OMER) today announced that its phosphodiesterase 7 (PDE7) inhibitors demonstrated robust efficacy in animal models of nicotine addiction.  These data add to earlier studies showing strong effects in models of cocaine addiction as well as binge eating.  Omeros' PDE7 program was founded on the Company's discovery of a previously unknown link between PDE7 and any movement disorder, such as Parkinson's disease.  Omeros believes that it also is the first to link PDE7 to any addiction or compulsive behavior, and is now advancing PDE7 inhibitors for the treatment of these as well as movement disorders. Omeros is collaborating on this program with both the National Institute on Drug Abuse (NIDA) and The Michael J. Fox Foundation.

The studies, conducted by well-recognized addiction researcher R. Ciccocioppo, Ph.D., and his colleagues at the University of Camarino, demonstrated that PDE7 inhibitors reduced nicotine self-administration and inhibited relapse induced by cues and stress.  Smoking is the leading cause of preventable disease, disability and death in the United States, and it is estimated that 1.3 billion people worldwide, or approximately 20% of the world's population, are smokers. The smoking cessation market was estimated at $3.1 billion in 2007. Chantix® (varenicline) is the pharmaceutical market leader for the treatment of nicotine addiction.  However, Chantix® received a black box warning from the U.S. Food and Drug Administration highlighting the risk of serious mental health events including changes in behavior, depressed mood, hostility, and suicidal thoughts when taking the drug.  PDE7 inhibitors are thought to exert their effect through a different mechanism than Chantix® and, therefore, may not have these side effects.

PDE7 appears to modulate the dopaminergic system, which plays a significant role in regulating both movement and addiction. Omeros believes that PDE7 inhibitors could be effective therapeutics for the treatment of movement disorders as well as addiction and compulsive disorders. Omeros had previously shown in animal models of cocaine addiction that PDE7 inhibitors reduce cocaine self-administration, inhibit relapse induced by cues and stress, and facilitate drug abstinence in previously addicted animals. Importantly, no effect on normal feeding was observed in the cocaine studies, suggesting that PDE7 inhibitors selectively reduce addiction-related behaviors. In a similarly well-established animal model of binge eating, Omeros' PDE7 inhibitors demonstrated equally robust efficacy, again showing no effect on normal feeding behavior.

Omeros' PDE7 Program Expands its Addiction Franchise

As previously announced, Omeros is evaluating peroxisome proliferator-activated receptor gamma (PPARγ) agonists for the treatment of addiction in two Phase 2 clinical studies. NIDA is funding substantially all costs of these studies, which are evaluating the effects of PPARγ agonists on oxycontin and heroin use. Pilot human and preclinical data suggest that PPARγ agonists may be most effective in the treatment of addiction to opioids, alcohol and nicotine, and that they are less effective for treating addiction to psychostimulants such as cocaine and methamphetamine. In contrast, preclinical data suggest that phosphodiesterase 7 (PDE7) inhibitors may be effective in the treatment of addiction to cocaine and methamphetamine, nicotine and compulsive behaviors. Together, the PPARγ and PDE7 programs provide Omeros with a potentially broad franchise of drug treatments for addiction and compulsive disorders. In addition, Omeros also believes that it controls the worldwide rights to any PDE7 inhibitor for the treatment of any movement disorder, including Parkinson's disease, restless leg syndrome and Huntington's disease. Omeros has licensed its PDE7 inhibitors from Daiichi Sankyo Co., Ltd. for worldwide exclusivity in the fields of movement disorders, addictions and compulsive disorders.