Arena Pharmaceuticals receives United States patent.

Arena Pharmaceuticals, Inc. (San Diego, CA) announced that the United States Patent and Trademark Office issued Arena a patent entitled "Non-Endogenous, Constitutively Activated Human Protein Coupled Receptors." This patent, United States Patent 6,555,339, covers one of Arena's proprietary methods of constitutively activating G protein-coupled receptors, or GPCRs, to facilitate drug screening. The patent describes a method for making a single amino acid change to GPCR sequences that causes the GPCR to favor an active state.

"This is an exciting development for Arena because it demonstrates that we are able to obtain patents on our core technologies that are broadly applicable to GPCRs. We believe that the ability to stabilize GPCRs in the active state and to reliably screen such GPCRs constitutes a robust discovery platform. This platform allows us to identify novel pharmacologically active compounds, such as inverse agonists and allosteric modulators, that regulate GPCR function," stated Dominic Behan, one of Arena's founders and Vice President, Research.

Including this patent, Arena owns or has exclusively licensed the following number of issued patents: 13 in the United States, 10 in European countries, two in Australia, two in New Zealand, and one in Japan. In addition, Arena has more than 220 pending patent applications before the United States Patent and Trademark Office, foreign patent offices and international patent authorities. These issued and pending patents are directed to Constitutively Activated Receptor Technology, or CART, Melanophore technology, chemical compositions of matter, methods of treatment utilizing chemical compositions, or GPCR genes. There is no assurance that any of these pending patents will issue, or that any of the issued patents will be enforceable or cover a drug product or other commercially significant product or method.

Arena is a biopharmaceutical company focused principally on discovering and developing drugs that act on GPCRs, an important class of drug targets. Arena uses its CART, Melanophore technology and other proprietary technologies to better understand GPCRs and to more efficiently and effectively identify compounds that may lead to new drugs. Arena focuses its efforts in four major therapeutic areas: metabolic diseases, cardiovascular diseases, central nervous system disorders and inflammatory diseases. In addition, Arena is pursuing an internal drug discovery program that is called Project Genesis. Project Genesis is comprised of the following steps: identifying therapeutically relevant GPCRs; determining expression levels and localization of these GPCRs; using Arena's proprietary technologies for high-throughput screening of these GPCRs against its chemical compound library; and optimizing small molecule leads identified from Arena's chemical library screens into drug candidates. With the completion of the sequencing of the human genome, Arena views Project Genesis as a strategic extension of its scientific and business capabilities that will allow Arena to discover new drug leads at therapeutically relevant GPCRs.

Arena Pharmaceuticals, Inc.

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