Arena Pharmaceuticals' Lorcaserin to Be Featured in Presentations at the American Diabetes Association's 70th Scientific Sessions

SAN DIEGO, June 17, 2010 -- /PRNewswire-FirstCall/ -- Arena Pharmaceuticals, Inc. (Nasdaq: ARNA) announced today that new data analyses from lorcaserin's pivotal Phase 3 clinical trial program will be presented in poster sessions at the American Diabetes Association's 70th Scientific Sessions in Orlando, Florida. The two posters highlighted below will be displayed in the Poster Hall from June 26, 2010, at 10:00 a.m. Eastern Time (ET) until June 28, 2010, at 4:00 p.m. ET.

- Changes in Glucose Tolerance and Cardiovascular Risk Factors after 52 Weeks of Treatment with Lorcaserin

The poster has been assigned presentation number 1855-P in category 19-B Obesity – Human, and has been selected to be featured on a guided tour titled Obesity – Human I, scheduled for June 26, 2010, from 11:30 a.m.-12:30 p.m. ET.

- Lorcaserin, a Selective 5-HT2C Agonist, is Efficacious for Weight Loss Across Patient Subgroups

The poster has been assigned presentation number 1845-P in category 19-B Obesity – Human, and has been selected to be featured on a guided tour titled Obesity – Human Treatment, scheduled for June 28, 2010, from 1:00-2:00 p.m. ET.

William R. Shanahan, M.D., Arena's Senior Vice President and Chief Medical Officer; Christen M. Anderson, M.D., Ph.D., Arena's Vice President, Clinical Development; and Meredith C. Fidler, Ph.D., Arena's Senior Clinical Scientist, will be available at the posters to discuss and address questions during the guided tours and on June 27, 2010, from 12:00-2:00 p.m. ET.

About Lorcaserin

Lorcaserin is a novel single agent that represents the first in a new class of selective serotonin 2C receptor agonists. The serotonin 2C receptor is expressed in the brain, including the hypothalamus, an area involved in the control of appetite and metabolism. Stimulation of this receptor is strongly associated with feeding behavior and satiety. Arena has patents that cover lorcaserin in the US and other jurisdictions, which in most cases are capable of continuing into 2023 without taking into account any patent term extensions or other exclusivity Arena might obtain.

Phase 3 Program Overview

The pivotal Phase 3 clinical trial program, BLOOM (Behavioral modification and Lorcaserin for Overweight and Obesity Management) and BLOSSOM (Behavioral modification and LOrcaserin Second Study for Obesity Management), evaluated nearly 7,200 patients treated for up to two years. In both trials, lorcaserin produced statistically significant weight loss with excellent safety and tolerability. These double-blind, randomized, placebo-controlled trials evaluated obese patients, Body Mass Index (BMI) 30 to 45, with or without co-morbid conditions and overweight patients, BMI 27 to 29.9, with at least one co-morbid condition, such as hypertension, cardiovascular diseases or glucose intolerance.

In addition to the pivotal program, Arena is evaluating lorcaserin in obese and overweight patients with type 2 diabetes in its BLOOM-DM (Behavioral modification and Lorcaserin for Overweight and Obesity Management in Diabetes Mellitus) trial. Results are expected late this year, and Arena plans to file the results of BLOOM-DM as a supplement to the NDA.

About Arena Pharmaceuticals

Arena is a clinical-stage biopharmaceutical company focused on discovering, developing and commercializing oral drugs that target G protein-coupled receptors, an important class of validated drug targets, in four major therapeutic areas: cardiovascular, central nervous system, inflammatory and metabolic diseases. Arena's most advanced drug candidate, lorcaserin, is intended for weight management, including weight loss and maintenance of weight loss, and has completed a pivotal Phase 3 clinical trial program. Arena has filed an NDA for lorcaserin with the FDA, and the FDA has assigned a PDUFA date of October 22, 2010, for the review of the application.

Arena Pharmaceuticals(R) and Arena(R) are registered service marks of the company.

Forward-Looking Statements

Certain statements in this press release are forward-looking statements that involve a number of risks and uncertainties. Such forward-looking statements include statements about the advancement, therapeutic indication and use, safety, efficacy, tolerability, regulatory review and potential of lorcaserin; the BLOOM-DM trial, including the filing of the results of such trial; lorcaserin's patent coverage; and Arena's focus, goals, strategy, research and development programs, and ability to develop compounds and commercialize drugs. For such statements, Arena claims the protection of the Private Securities Litigation Reform Act of 1995. Actual events or results may differ materially from Arena's expectations. Factors that could cause actual results to differ materially from the forward-looking statements include, but are not limited to, regulatory authorities or advisors may not find data from Arena's clinical trials and other studies sufficient for regulatory approval; the timing and ability of Arena to receive regulatory approval for its drug candidates; the timing, success and cost of Arena's lorcaserin program and other of its research and development programs; results of clinical trials and other studies are subject to different interpretations and may not be predictive of future results; clinical trials and other studies may not proceed at the time or in the manner Arena or others expect or at all; Arena's ability to enter into agreements to develop or commercialize its compounds or programs; Arena's ability to commercialize lorcaserin with a pharmaceutical company or independently; Arena's ability to obtain adequate funds; Arena's ability to obtain and defend its patents; and the timing and receipt of payments and fees, if any, from Arena's collaborators. Additional factors that could cause actual results to differ materially from those stated or implied by Arena's forward-looking statements are disclosed in Arena's filings with the Securities and Exchange Commission. These forward-looking statements represent Arena's judgment as of the time of this release. Arena disclaims any intent or obligation to update these forward-looking statements, other than as may be required under applicable law.

SOURCE Arena Pharmaceuticals, Inc.