Arena Pharmaceuticals and Ildong Pharmaceutical Enter Into Co-Development and License Agreement for Temanogrel, a Novel Agent for Thrombotic Diseases

SAN DIEGO, Nov. 28, 2012 /PRNewswire/ -- Arena Pharmaceuticals, Inc. (NASDAQ: ARNA) today announced that it has entered into a co-development and license agreement with Ildong Pharmaceutical Co., Ltd., for temanogrel, Arena's internally discovered inverse agonist of the serotonin 2A receptor. The agreement grants Ildong exclusive rights to commercialize temanogrel in South Korea for myocardial infarction, acute coronary syndrome, stroke, peripheral artery disease, and other cardiovascular diseases, subject to further development and regulatory approval of temanogrel. Initially, Ildong will be responsible for funding and conducting, under the direction of a joint steering committee, the next two planned clinical trials in this program: an additional Phase 1 trial in healthy volunteers and a Phase 2a proof-of-concept trial in patients.

"The Phase 1 trials Arena previously conducted support temanogrel's potential to treat a variety of conditions related to thrombosis through a novel mechanism that may provide advantages over currently available therapies," said Jack Lief, Arena's President and Chief Executive Officer. "A successful product in this category has the potential to serve as an important treatment option for many patients, and this collaboration with Ildong enables us to resume clinical development in a cost-effective manner."

Arena will maintain ownership of temanogrel outside of South Korea, and has the rights to use data generated by Ildong for the development and potential commercialization of temanogrel outside of South Korea by Arena or other Arena licensees. In addition, Ildong has agreed to pay Arena a $2 million development milestone if the planned additional Phase 1 and Phase 2a clinical trials conducted by Ildong support continued development and Arena or another Arena licensee initiates a Phase 2b clinical trial of temanogrel. Arena is also eligible to receive a royalty on net sales of temanogrel in South Korea, while Ildong is eligible to receive a share of future payments received by Arena related to licensing transactions and sales of temanogrel in other territories.

"It is a great pleasure to establish this collaboration with Arena for temanogrel," said Jung-chi Lee, Ildong's Chairman and Chief Executive Officer. "We look forward to supporting the global development of this drug candidate and having the opportunity to bring temanogrel to patients in South Korea as a treatment for thrombotic diseases."

About Thrombosis

Thrombosis is the formation of a clot, or thrombus, inside a blood vessel. Thrombus formation that occurs in the blood vessels of the heart or brain can lead to serious thrombotic diseases including myocardial infarction, acute coronary syndrome and stroke. One of the initial events in thrombus formation is the activation of platelets, which then aggregate and adhere to one another as they release certain factors, including high concentrations of serotonin. Serotonin promotes further platelet aggregation and also causes constriction, or narrowing, of the blood vessels. Elevated serotonin levels have been associated with increased cardiovascular risk. The prothrombotic effects of serotonin on platelets and blood vessels are mediated by the serotonin 2A receptor, and inverse agonists of the serotonin 2A receptor have the potential to inhibit this activity.

About Temanogrel

Temanogrel is an inverse agonist of the serotonin 2A receptor intended for the treatment of thrombotic diseases, and has completed single- and multiple-ascending dose Phase 1 trials in healthy volunteers. Temanogrel has the potential to prevent serotonin-mediated platelet aggregation and reverse serotonin-mediated vasoconstriction. This dual mechanism of temanogrel may be therapeutically useful for the treatment or prevention of thrombotic diseases.

About Arena Pharmaceuticals

Arena Pharmaceuticals is a biopharmaceutical company focused on discovering, developing and commercializing novel drugs for weight management, cardiovascular disease, inflammation and other disorders. BELVIQ^® (lorcaserin HCl), Arena's internally discovered drug, was approved by the US Food and Drug Administration in June 2012, and is under review for regulatory approval in additional territories. Arena's US operations are located in San Diego, California, and its operations outside of the United States, including its commercial manufacturing facility, are located in Zofingen, Switzerland. For more information, visit Arena's website at www.arenapharm.com.

Arena Pharmaceuticals^® and Arena^® are registered service marks of Arena Pharmaceuticals, Inc. BELVIQ^® is a registered trademark of Arena Pharmaceuticals GmbH.

About Ildong Pharmaceutical Co., Ltd.

Ildong Pharmaceutical Co., Ltd., based in Seoul, Korea, is a leading Korean company focused on the development, manufacturing and marketing of pharmaceuticals and OTC products with sales of $294 million in 2011. Ildong, founded in 1941, is known to have leading expertise in various therapeutic categories, including antibiotics, gastrointestinal, anti-diabetics, cardiovascular and oncology. For more information, visit Ildong's website at www.ildong.com.

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 development, therapeutic indication and use, safety, efficacy, mechanism of action, regulatory approval and commercialization of temanogrel; the potential of temanogrel and other products in the same category, including as compared to other therapies; rights, obligations, expectations and future activities related to the co-development and license agreement with Ildong, including funding, the development and commercialization of temanogrel and milestone and other payments, the significance of such agreement, and the cost-effectiveness of development thereunder; Arena's use of data generated under such agreement, ownership of temanogrel and establishment of other licensing agreements relating to temanogrel; the regulatory review of BELVIQ; and Arena's focus, goals, strategy, research and development programs, and ability to discover and develop compounds and commercialize drugs. 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, but are not limited to, the following: risks related to the implementation and continuation of the co-development and license agreement with Ildong and the development of temanogrel; risks related to commercializing drugs, including regulatory, manufacturing and supply issues and the pace of market acceptance; cash and revenues generated from BELVIQ, including the impact of competition; the timing and outcome of regulatory review is uncertain; government and commercial reimbursement and pricing decisions; risks related to relying on collaborative arrangements; the timing and receipt of payments and fees, if any, from collaborators; the entry into or modification or termination of collaborative arrangements; 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; data and other information related to any of Arena's research and development may not meet safety, efficacy or other regulatory requirements or otherwise be sufficient for further research and development, regulatory review or approval or continued marketing; Arena's ability to obtain and defend patents; the timing, success and cost of Arena's research and development programs; 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; having adequate funds; and satisfactory resolution of litigation or other disagreements with others. Additional factors that could cause actual results to differ materially from those stated or implied by Arena's forward-looking statements are 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.

SOURCE Arena Pharmaceuticals, Inc.