Arena Pharmaceuticals Announces Shareholders and Board of Directors Approve Reverse Stock Split

SAN DIEGO, June 14, 2017

"We started last year with a charter to reset Arena.  This reverse stock split is another step toward driving long-term shareholder value," stated Amit Munshi, President and CEO of Arena.  "We continue to look forward to the upcoming ralinepag Phase 2 data readout in July."

Upon the effectiveness of the reverse stock split, each 10 shares of the Company's issued and outstanding common stock will be automatically combined and converted into one issued and outstanding share of common stock, par value $0.0001 per share. As a result of the reverse split, there will be approximately 31.7 million shares of common stock issued and outstanding. The common shares will trade under a new CUSIP number, 040047 607, effective June 19, 2017.  All options, warrants, and convertible securities of the Company outstanding immediately prior to the reverse stock split will be adjusted.

No fractional shares of common stock will be issued as a result of the reverse stock split. Stockholders of record who would otherwise be entitled to receive a fractional share will receive a cash payment in lieu thereof. 

Arena has chosen its transfer agent, Computershare Inc., to act as exchange agent for the reverse stock split.  Stockholders owning shares via a bank, broker or other nominee will have their positions automatically adjusted to reflect the reverse stock split, and will not be required to take further action in connection with the reverse stock split, subject to brokers' particular processes.  For those stockholders holding physical stock certificates, Computershare will send instructions for exchanging those certificates for shares held in book-entry form representing the post-split number of shares.  Computershare can be reached at (877) 854-4583.

About Arena Pharmaceuticals
At Arena, we are 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 including ulcerative colitis (UC), and APD371 in Phase 2 evaluation for the treatment of pain associated with Crohn's disease. In addition, we have 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. These statements can be identified by introductory words such as "expects," "plan," "believes," "will," "achieve," "anticipate," "would," "should," "subject to" or words of similar meaning, and by the fact that they do not relate strictly to historical or current facts.  Such forward-looking statements include statements regarding driving long-term value; timing of data readout; Arena's focus, goals, strategy and clinical programs; and statements regarding the reverse stock split.  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 the timing of regulatory approval; the timing and outcome of research, development and regulatory review is uncertain; we expect to need additional funds to advance all of our programs, and you and others may not agree with the manner we allocate our resources; our drug candidates may not advance in development or be approved for marketing; risks related to developing and commercializing drugs; unexpected or unfavorable new data; nonclinical and clinical data is voluminous and detailed, and regulatory agencies may interpret or weigh the importance of data differently and reach different conclusions than Arena or others, request additional information, have additional recommendations or change their guidance or requirements before or after approval; Arena's and third parties' intellectual property rights; 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 expected or at all; and those factors 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.