Arena Pharmaceuticals is a clinical-stage biopharmaceutical company focused on discovering, developing and commercializing oral drugs that target G protein-coupled receptors, or GPCRs, in four major therapeutic areas: cardiovascular, central nervous system, inflammatory and metabolic diseases.

Our Focus

We focus on GPCRs because they are a validated class of drug targets that mediate the majority of cell-to-cell communication in humans. A high percentage of today’s prescription drugs target one or more GPCRs, and we believe that approved GPCR-based drugs target only approximately one-third of the known non-sensory GPCRs. Selective targeting of specific GPCRs is intended to increase the likelihood of the desired pharmacology and minimize the risk of “off target” effects. We believe our GPCR-focused technologies and integrated discovery and development capabilities will allow us to continue to build our pipeline of unique and selective drug candidates.

Our Development Pipeline

Our most advanced drug candidate is lorcaserin for weight management. Lorcaserin has completed a pivotal Phase 3 clinical trial program and is under review by the FDA for U.S. marketing approval. In 2009, we reported positive results from the two trials comprising lorcaserin’s pivotal Phase 3 clinical trial program, BLOOM and BLOSSOM. In addition to the pivotal program, we are evaluating lorcaserin in obese and overweight patients with type 2 diabetes in our Phase 3 BLOOM-DM trial. We plan to file the results of BLOOM-DM as a supplement to the NDA.

In addition to lorcaserin, our internal development programs include APD791, APD916 and APD811, all of which are oral drug candidates that we internally discovered. APD791 is a selective inverse agonist of the serotonin 2A receptor intended for the treatment of arterial thrombosis and other related conditions, and it has completed Phase 1a and Phase 1b clinical trials. APD916 is a histamine H3 inverse agonist intended for the treatment of narcolepsy and cataplexy, and we initiated a Phase 1 clinical trial for this drug candidate in March 2010. APD811 is a selective agonist of the prostacyclin receptor intended for the treatment of pulmonary arterial hypertension, and it is in preclinical development.

Along with our internal programs, we have a clinical-stage collaboration with Ortho-McNeil-Janssen Pharmaceuticals, Inc., or Ortho-McNeil-Janssen, to develop compounds for the treatment of type 2 diabetes and other disorders by targeting the GPR119 receptor.

Our Strategy

The key elements of our scientific and business strategy are to:

• Commercialize lorcaserin.  We intend to commercialize lorcaserin initially in the U.S. and then in other major markets independently or with a pharmaceutical company or companies.
• Selectively advance our other lead candidates.  We intend to selectively advance our pipeline of drug candidates independently or through licensing, collaborations or other opportunities.
• Maintain research capabilities to discover and develop additional drug candidates.  Our technologies, our drug discovery infrastructure and the integrated approach to research used by our scientists have allowed us to identify a number of GPCR targets and novel compounds. We intend to maintain discovery research capabilities to fuel our pipeline.
• Focus on attractive market opportunities.  We intend to continue to develop drug candidates with large market opportunities, including obesity and type 2 diabetes, but also consider smaller market opportunities that might offer attractive commercial potential.
• Improve our capabilities.  To capitalize on our discoveries, we plan to selectively improve our capabilities as our drug candidates enter into, and move through, clinical trials and to commercialization.

Our drug candidates have not been approved by the U.S. Food and Drug Administration or any international regulatory agency.