Arena Pharmaceuticals, Inc.
Jan 4, 2001

Arena Pharmaceuticals, Inc. Expects First Profitable Quarter, Strong Fourth Quarter 2000 Results and Sets Conference Call

SAN DIEGO, Jan. 4 /PRNewswire/ Arena Pharmaceuticals, Inc. (Nasdaq: ARNA) today announced that it will host both a telephone and internet fourth quarter conference call on Thursday, January 18, 2001 at 4:30 p.m. Eastern Time (1:30 p.m. San Diego Time).

Jack Lief, president and chief executive officer, and Joseph Mooney, chief financial officer, will discuss the fourth quarter results and expand upon the summary points raised above, and will also provide information as to the Company's outlook for 2001, the progress of Arena's CART Technology collaborations, and other topics. A Question and Answer session will follow the presentation. To access by telephone, dial in toll free at 800-288-8968 and specify that you would like to join the "Fourth Quarter Earnings Conference Call." To access the call via the Internet, go to www.arenapharm.com and click on "Investor Relations." Then, click on "Calendar of Events." The conference call will be listed at the top of the page. Click on the "Live Webcast" link. Then, follow the links and instructions provided. Listening to the conference call on the Internet will require speakers and RealPlayer.

Arena's CART Technology allows for the direct identification of modulators of G protein-coupled receptors (GPCR) in a ligand-independent manner, making the technology particularly useful with respect to orphan GPCRs that are estimated to comprise approximately 2% of the human genome. Such ligand independent screening is made possible by genetic alteration of these receptors, using routinely applicable and proprietary genetic cassettes. Arena has established collaborations with Eli Lilly and Company, Fujisawa Pharmaceutical Co., Ltd., Taisho Pharmaceutical Co., Ltd., Lexicon Genetics, Inc. and Neurocrine Biosciences, Inc.

"Arena Pharmaceuticals" and the corporate logo are registered U.S. trademarks of the company. "Arena" and "CART" are trademarks of the company. Arena's headquarters are located at 6166 Nancy Ridge Drive, San Diego, CA 92121. On the Internet, please refer to the Investor Relation's Center at Arena's website: http://www.arenapharm.com for further information. SOURCE Arena Pharmaceuticals, Inc.

CONTACT: Jack Lief, President and CEO of Arena Pharmaceuticals, Inc., 858-453-7200/