Boehringer Ingelheim and Arena Pharmaceuticals Collaborate to Advance Research in Schizophrenia

Ingelheim, Germany, and San Diego, CA, USA, January 13, 2016 - Boehringer Ingelheim and Arena Pharmaceuticals, Inc. (NASDAQ: ARNA) announced today that they have signed an exclusive agreement to conduct joint research to identify drug candidates targeting an undisclosed G protein-coupled receptor (GPCR), which belongs to the group of orphan CNS receptors. An “orphan receptor” is structurally related to a family of proteins that are known to act as functional cell-surface receptors but whose ligand has not yet been identified.

Arena will provide Boehringer Ingelheim exclusive rights to its internally discovered, novel compounds and intellectual property for an orphan CNS receptor. The companies will jointly conduct research to identify additional drug candidates that are suitable for continued research and development as therapeutic compounds for various disease indications. The agreement grants Boehringer Ingelheim exclusive worldwide rights to develop, manufacture and commercialize products resulting from the collaboration.

According to the World Health Organization, mental illness - together with substance abuse disorders - remains the leading cause of disability worldwide. At least 450 million people¹ suffer from mental health problems. The global economic burden of mental illness is larger than for cancer, cardiovascular disease or diabetes and continues to grow – with significant health, social and economic consequences. As currently available treatment options leave many patients unsatisfactorily treated, more effective medicines for mental diseases are urgently needed.

“This agreement reflects our new corporate focus to enter into collaboration opportunities at various stages of development,” said Harry F. Hixson, Jr., Arena’s interim Chief Executive Officer. “Collaborations are an essential part of our drug discovery and development efforts, so we are pleased to be part of this shared goal to identify novel drugs targeting an orphan CNS receptor with Boehringer Ingelheim, who possesses demonstrated capabilities in research, development, manufacturing, and marketing of pharmaceutical products.”

“Together with our research partners in neuroscience, we are targeting brain circuits underlying major untreated symptom domains in our CNS focus areas of Alzheimer’s disease, schizophrenia, and depression. We are delighted to enter into this new collaboration with Arena, who have recognized expertise in orphan CNS GPCR drug discovery and development,” said Corporate Senior Vice President Clive R. Wood, Head of Discovery Research of Boehringer Ingelheim. “We believe that this alliance with Arena will allow us to deliver innovative, new medicines for the treatment of patients with psychiatric diseases such as schizophrenia and contribute to our vision of helping the millions of people with mental illness, to live fuller, more independent lives, for longer.”

The new partnership combines Arena’s expertise in GPCR focused drug discovery and development with Boehringer Ingelheim’s unique approach to CNS research and development and its proven capabilities in bringing novel medications of high therapeutic value to the market in areas of high unmet medical need.

The collaboration is part of Boehringer Ingelheim’s commitment to researching and developing new and more effective treatments for psychiatric diseases and their symptoms.

Under the terms of the agreement, Arena is eligible to receive payments up to $262 million in success milestones in case of full commercial success of multiple drug products, including an upfront payment and research funding. In addition, Arena is eligible to receive tiered royalties on future sales of products that arise from the collaboration. Further details of the agreement were not disclosed.

Notes to Editors

Intended audiences 
This press release is issued from our Corporate Headquarters in Ingelheim, Germany and is intended to provide information about our global business. Please be aware that information relating to the approval status and labels of approved products may vary from country to country, and a country-specific press release on this topic may have been issued in the countries where we do business.

About Boehringer Ingelheim
The Boehringer Ingelheim group is one of the world’s 20 leading pharmaceutical companies. Headquartered in Ingelheim, Germany, Boehringer Ingelheim operates globally with 146 affiliates and a total of more than 47,700 employees. The focus of the family-owned company, founded in 1885, is researching, developing, manufacturing and marketing new medications of high therapeutic value for human and veterinary medicine.

Social responsibility is an important element of the corporate culture at Boehringer Ingelheim. This includes worldwide involvement in social projects, such as the initiative “Making more Health” and caring for the employees. Respect, equal opportunities and reconciling career and family form the foundation of the mutual cooperation. In everything it does, the company focuses on environmental protection and sustainability.

In 2014, Boehringer Ingelheim achieved net sales of about 13.3 billion euros. R&D expenditure corresponds to 19.9 per cent of its net sales.

For more information please visit www.boehringer-ingelheim.com

About Arena Pharmaceuticals
Arena embraces the challenge of improving health by seeking to bring innovative medicines targeting G protein-coupled receptors to patients. Arena’s focus is discovering, developing and commercializing drugs to address unmet medical needs, and BELVIQ^® (lorcaserin HCl) is Arena’s first internally discovered drug approved for marketing. Arena has US operations located in San Diego, California, and operations outside of the United States, including its commercial manufacturing facility, 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.

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 Arena and Boehringer Ingelheim collaboration, including related rights, obligations, activities, milestones, payments, and other expectations; the identification, advancement, therapeutic indication, marketing approval, commercialization and potential of compounds under such collaboration; the need for new treatments for mental diseases and the potential of expected activities under such collaboration in addressing such need; the importance of collaborations to Arena’s efforts; embracing the challenge of improving health; seeking to bring innovative medicines to patients; and Arena’s focus, plans, goals, strategy, expectations, 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: no compound under the Arena and Boehringer Ingelheim collaboration may be identified, advanced, approved for marketing or commercialized for any disease or condition; having adequate funds and other assets and their effective use; risks related to commercializing BELVIQ or any future drug, including regulatory, manufacturing, supply and marketing issues and their availability and use; the risk that Arena’s revenues are based in part on estimates, judgment and accounting policies, and incorrect estimates or disagreement regarding estimates or accounting policies may result in changes to Arena’s guidance or previously reported results; the timing and outcome of regulatory review is uncertain, and lorcaserin may not receive any additional marketing approvals; regulatory decisions in one territory may impact other regulatory decisions and Arena’s business prospects; 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; the timing, success and cost of Arena’s research and development and related strategy and decisions; 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; 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 regulatory requirements or otherwise be sufficient for (or Arena or a collaborator may not pursue) further research and development, regulatory review or approval or continued marketing; Arena’s and third parties’ intellectual property rights; and satisfactory resolution of litigation or other disagreements. 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.