Arena Pharmaceuticals to Present at the 16th Annual Needham Healthcare Conference on April 4th

SAN DIEGO, March 27, 2017

A live audio webcast of the presentation will be available under the investor relations section of Arena's website at www.arenapharm.com. A replay of the presentation will be available for 30 days following the event.

About Arena Pharmaceuticals
Arena Pharmaceuticals is a biopharmaceutical company focused on developing novel, small molecule drugs with optimized receptor pharmacology designed to deliver broad clinical utility across multiple therapeutic areas. Our proprietary pipeline includes potentially first- or best-in-class programs for which we own global commercial rights.  Our three most advanced investigational clinical programs are ralinepag (APD811) in Phase 2 evaluation for pulmonary arterial hypertension (PAH), etrasimod (APD334) in Phase 2 evaluation for multiple autoimmune indications, and APD371 entering Phase 2 evaluation for the treatment of pain associated with Crohn's disease. In addition, Arena has collaborations with the following pharmaceutical companies: Eisai Co., Ltd. and Eisai Inc. (commercial stage), Axovant Sciences (Phase 2 candidate), and Boehringer Ingelheim International GmbH (preclinical candidate).

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 upcoming presentation; and Arena's focus, the potential of its programs, and collaborations. 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 those 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.

Contact: Arena Pharmaceuticals, Inc.
Kevin R. Lind, Chief Financial Officer
klind@arenapharm.com
858.210.3636