LORCASERIN HYDROCHLORIDE FOR ARENA DRUG CANDIDATE APD356

Arena Pharmaceuticals, Inc. announced today that the United States Adopted Names (USAN) Council has approved the nonproprietary name lorcaserin hydrochloride for APD356, a selective 5-HT2C serotonin receptor agonist under investigation for the treatment of obesity. Lorcaserin hydrochloride, which is orally administered and was internally discovered by Arena, is expected to enter Phase 3 clinical development in the second half of 2006. Yahoo News (http://biz.yahoo.com/prnews/060505/laf029.html?.v=52)