ARENA ENROLLS PATIENTS IN OBESITY TRIAL

Arena Pharmaceuticals has completed patient enrollment in the first of three planned Phase III pivotal trials evaluating the efficacy and safety of its lead drug candidate, lorcaserin hydrochloride, for the treatment of obesity. Known as BLOOM, this double-blind, randomized, placebo-controlled trial enrolled 3,182 patients at approximately 100 centers in the U.S. Arena expects that BLOOM's independent data safety monitoring board will perform its six-month review of echocardiograms during the third quarter and deicide whether it is appropriate to continue the trial.

The BLOOM trial is evaluating a 20-mg daily dose of lorcaserin versus placebo over a two-year treatment period in obese patients (those with body mass indexes of 30 to 45) with or without co-morbid conditions and overweight patients (those with body mass indexes of 27 to 30) with at least one co-morbid condition. The proportion of patients with a 5 percent or greater weight reduction from baseline at week 52 is the primary efficacy endpoint. All patients received echocardiograms at screening and will receive follow-up echocardiograms at six, 12, 18 and 24 months after starting the trial.

The complete lorcaserin Phase III program is designed to enroll a total of approximately 6,000 overweight and obese patients in three pivotal trials. In addition to the BLOOM trial, two additional Phase III pivotal trials enrolling a total of approximately 3,000 patients will be initiated. In these additional pivotal trials, Arena plans to evaluate the 20- and 10-mg daily doses versus placebo over a one-year treatment period, with one of the trials likely evaluating patients who also have Type 2 diabetes. Diet and exercise will be part of each of the pivotal trials in accordance with FDA guidelines.

Lorcaserin stimulates the 5-HT2C serotonin receptor, located in the hypothalamus, an area of the brain which helps regulate satiety and influences metabolic rate. Results from a Phase II study demonstrated that treatment with lorcaserin produced highly statistically significant, progressive and dose-dependent weight loss over a 12-week period.