Arena Pharmaceuticals S3ASR Automatic shelf registration

Arena Pharmaceuticals (ARNA) S-3ASRAutomatic shelf registration

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As filed with the Securities and Exchange Commission on February 27, 2020

RegistrationNo. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORMS-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ARENA PHARMACEUTICALS, INC.

(Exact Name of Registrant as Specified in its Charter)

Delaware

23-2908305

(State or Other Jurisdiction of

Incorporation or Organization)

(I.R.S. Employer

Identification No.)

6154 Nancy Ridge Drive

San Diego, California 92121

858.453.7200

(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant’s Principal Executive Offices)

Amit D. Munshi

President and Chief Executive Officer

6154 Nancy Ridge Drive

San Diego, California 92121

858.453.7200

(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent for Service)

Copies to:

Steven M. Przesmicki, Esq.

Cooley LLP

4401 Eastgate Mall

San Diego, California 92121

858.550.6000

Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this registration statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement of the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ☒

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, anon-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

CALCULATION OF REGISTRATION FEE



Title of Class of Securities to be Registered	Proposed Maximum Aggregate Offering Price	Amount of Registration Fee
Common Stock, par value $0.0001 per share	(1)	(2)
Common Stock, par value $0.0001 per share, offered pursuant to Sales Agreement	$250,000,000	$32,450 (3)
Total (4)	$250,000,000	$32,450

(1)	Omitted pursuant to FormS-3 General Instruction II.E. Such indeterminate number or amount of common stock is being registered as may from time to time be offered at indeterminate prices.

(2)	In accordance with Rules 456(b) and 457(r) under the Securities Act of 1933, as amended, the registrant is deferring payment of all applicable registration fees.

(3)	Calculated pursuant to Rule 457(o) and Rule 457(r) under the Securities Act.

(4)	Does not include registration fees deferred in accordance with Rules 456(b) and 457(r) under the Securities Act, as described in Note (2) above.

EXPLANATORY NOTE

This registration statement contains:

•

a base prospectus, which covers the offering, issuance and sale by us of our common stock from time to time in one or more offerings; and

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a sales agreement prospectus, which covers the offering, issuance and sale by us of up to a maximum aggregate offering price of $250,000,000 of our common stock that may be issued and sold from time to time under a sales agreement with Credit Suisse Securities (USA) LLC, SVB Leerink LLC and Cantor Fitzgerald & Co.

The base prospectus immediately follows this explanatory note. The specific terms of any offering of our common stock pursuant to the base prospectus will be specified in one or more prospectus supplements to the base prospectus. The sales agreement prospectus immediately follows the base prospectus.

PROSPECTUS

LOGO

Arena Pharmaceuticals, Inc.

Common Stock

We may, from time to time, offer and sell shares of our common stock in amounts, at prices and on terms described in one or more supplements to this prospectus. We may also authorize one or more free writing prospectuses to be provided to you in connection with these offerings.

This prospectus describes some of the general terms that may apply to an offering of our common stock. The specific terms and any other information relating to a specific offering will be set forth in a post-effective amendment to the registration statement of which this prospectus is a part, in a supplement to this prospectus or in a free writing prospectus, or may be set forth in one or more documents incorporated by reference in this prospectus. You should read this prospectus, the information incorporated by reference into this prospectus and any applicable prospectus supplement or free writing prospectus carefully before you invest.

Shares of our common stock may be sold by us to or through underwriters or dealers, directly to purchasers or through agents designated from time to time. For additional information on the methods of sale, you should refer to the section entitled “Plan of Distribution” in this prospectus and in the applicable prospectus supplement. If any underwriters are involved in the sale of any common stock with respect to which this prospectus is being delivered, the names of such underwriters and any applicable discounts or commissions and options to purchase additional shares will be set forth in a prospectus supplement. The price to the public of such securities and the net proceeds we expect to receive from such sale will also be set forth in a prospectus supplement.

Our common stock is listed on The Nasdaq Global Select Market under the symbol “ARNA.” On February 25, 2020, the last reported sale price of our common stock on The Nasdaq Global Select Market was $47.79 per share.

Investing in our common stock involves a high degree of risk. See “Risk Factors” on page 2 of this prospectus and as updated in our future filings made with the Securities and Exchange Commission that are incorporated by reference into this prospectus.

This prospectus may not be used to offer or sell any securities unless accompanied by a prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is February 27, 2020.

TABLE OF CONTENTS


	Page
About this Prospectus		i
Summary		1
Risk Factors		2
Special Note Regarding Forward-Looking Statements		2
Use of Proceeds		3
Description of Capital Stock		4
Plan of Distribution		6
Legal Matters		8
Experts		8
Where You Can Find More Information		8
Incorporation by Reference		8

We have not authorized anyone to provide you with information other than the information contained in or incorporated by reference into this prospectus or any applicable prospectus supplement or free writing prospectus that we may authorize in connection with an offering of our common stock. We are not making an offer to sell or seeking an offer to buy shares of our common stock under this prospectus or any applicable prospectus supplement or free writing prospectus in any jurisdiction where the offer or sale is not permitted. The information contained in this prospectus, any applicable prospectus supplement or free writing prospectus, and the documents incorporated by reference herein and therein are accurate only as of their respective dates, regardless of the time of delivery of this prospectus or any sale of a security.

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on FormS-3 that we filed with the Securities and Exchange Commission, or SEC, using a “shelf” registration process as a “well-known seasoned issuer,” as defined in Rule 405 under the Securities Act of 1933, as amended, or the Securities Act. Under this shelf registration statement, we may sell from time to time in one or more offerings the common stock described in this prospectus. No limit exists on the aggregate number of shares that we may sell pursuant to the registration statement.

Each time we sell any common stock under this prospectus, we will provide a prospectus supplement that will contain more specific information about the terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to an offering of our common stock. The prospectus supplement, or information incorporated by reference in this prospectus or any prospectus supplement that is of a more recent date, may also add, update or change information contained in this prospectus. To the extent that any statement that we make in a prospectus supplement is inconsistent with statements made in this prospectus, the statements made in this prospectus will be deemed modified or superseded by those made in the prospectus supplement. You should read both this prospectus and any applicable prospectus supplement, together with the additional information described below under the heading “Where You Can Find More Information.” This prospectus may not be used to consummate a sale of our common stock unless it is accompanied by a prospectus supplement. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to an offering of our common stock.

Arena Pharmaceuticals®, Arena® and our corporate logo are registered service marks of Arena. All other brand names or trademarks appearing in this prospectus are the property of their respective holders. Unless otherwise specified or required by context, references in this prospectus to “Arena Pharmaceuticals,” “Arena,” “we,” “us” and “our” refer to Arena Pharmaceuticals, Inc., and its wholly owned subsidiaries on a consolidated basis.

SUMMARY

The following summary highlights information contained elsewhere or incorporated by reference in this prospectus. This summary does not contain all the information that may be important to purchasers of our common stock. Prospective purchasers of our common stock should carefully read and consider this entire prospectus, all documents incorporated by reference herein, any prospectus supplement accompanying this prospectus, and any related free writing prospectus.

Company Overview

We are a biopharmaceutical company focused on delivering novel, transformational medicines with optimized pharmacology and pharmacokinetics to patients globally. Our internally-developed pipeline includes multiple potentially first- or best-in-class assets with broad clinical utility.

Our most advanced investigational clinical programs include: etrasimod (APD334), being evaluated in a Phase 3 program for ulcerative colitis, a Phase 2b/3 program for Crohn’s disease, and a Phase 2b program in atopic dermatitis. We also plan to evaluate etrasimod in a Phase 2b program for eosinophilic esophagitis, and a Phase 2 program in alopecia areata. Olorinab (APD371) is being evaluated for a broad range of visceral pain conditions associated with gastrointestinal diseases and is currently in a Phase 2b trial for treatment of abdominal pain associated with irritable bowel syndrome. APD418 is being evaluated in a Phase 1 trial for acute heart failure.

We continue to leverage our two decades of world-class G-protein-coupled receptor, or GPCR, target discovery research to develop breakthrough drugs and ultimately deliver these to patients with large unmet needs. Our long-term pipeline prospects include an enhanced collaboration with Beacon Discovery across a broad range of immune-mediated inflammatory targets and compounds (which we refer to as Project Cabrillo) and the buildout of Arena Neuroscience to focus on treating neurological conditions with microglial neuroinflammation.

We have license agreements or collaborations with various companies, including United Therapeutics (ralinepag in a Phase 3 program for pulmonary arterial hypertension), Everest Medicines Limited (etrasimod in development in Greater China and select countries in Asia), Beacon Discovery (early research platform for GPCR targets), Boehringer Ingelheim International GmbH (undisclosed orphan GPCR program for central nervous system - preclinical), and Eisai Co., Ltd. and Eisai Inc. (BELVIQ^®/BELVIQ XR^®).

Company Information

We incorporated in the state of Delaware in April 1997. Our corporate offices are located at 6154 Nancy Ridge Drive, San Diego, California 92121, our telephone number is 858.453.7200 and our website address is www.arenapharm.com. The information contained in or accessible through our website does not constitute part of this prospectus.

RISK FACTORS

An investment in our common stock involves risks. Prior to making a decision about investing in our common stock, you should carefully consider the specific risks discussed under “Risk Factors” in any applicable prospectus supplement and in our filings with the SEC incorporated by reference in this prospectus, together with all of the other information contained in this prospectus and any applicable prospectus supplement or incorporated by reference in this prospectus. The risks and uncertainties described in any applicable prospectus supplement and in our SEC filings are not the only ones facing us. Additional risks and uncertainties not presently known to us, or that we currently see as immaterial, may also harm our business. If any of the risks or uncertainties described in any applicable prospectus supplement or our SEC filings or any such additional risks and uncertainties actually occur, our business, results of operations and financial condition could be materially and adversely affected. In that case, the trading price of our common stock could decline, and you might lose all or part of your investment.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and any applicable prospectus supplement or free writing prospectus, including the documents that we incorporate by reference herein and therein, contain “forward-looking statements” within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act. These forward-looking statements can generally be identified as such because the context of the statement will include words such as “may,” “will,” “intend,” “plan,” “believe,” “anticipate,” “expect,” “estimate,” “predict,” “potential,” “continue,” “likely,” “unlikely” or “opportunity,” the negative of these words or words of similar import. Similarly, statements that describe our future plans, strategies, intentions, expectations, objectives, goals or prospects are also forward-looking statements. Discussions containing these forward-looking statements may be found, among other places, in the “Business” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections incorporated by reference from our most recent Annual Report on Form10-K and our Quarterly Reports on Form10-Q for the quarterly periods ended subsequent to our filing of such Annual Report on Form10-K, as well as any amendments thereto reflected in subsequent filings with the SEC. These forward-looking statements are based largely on our expectations and projections about future events and future trends affecting our business, and are subject to risks and uncertainties that could cause actual results to differ materially from those anticipated in the forward-looking statements. The risks and uncertainties include, among others, those noted in “Risk Factors” above and in any applicable prospectus supplement or free writing prospectus, and those included in the documents that we incorporate by reference herein and therein. In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date the statement is made, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and you are cautioned not to unduly rely upon these statements.

In addition, past financial and/or operating performance is not necessarily a reliable indicator of future performance and you should not use our historical performance to anticipate results or future period trends. We can give no assurances that any of the events anticipated by the forward-looking statements will occur or, if any of them do, what impact they will have on our results of operations and financial condition. Except as required by law, we undertake no obligation to publicly revise our forward-looking statements to reflect events or circumstances that arise after the filing of this prospectus or any applicable prospectus supplement or free writing prospectus, or documents incorporated by reference herein and therein, that include forward-looking statements.

USE OF PROCEEDS

Except as described in any prospectus supplement, we currently intend to use the net proceeds from the sale of common stock under this prospectus for the clinical and preclinical development of drug candidates, for general corporate purposes, including working capital and costs associated with manufacturing services, and for capital expenditures. We may also use a portion of the net proceeds to acquire drugs or drug candidates, technologies, businesses or other assets, although we have no current plans, commitments or agreements to do so as of the date of this prospectus. The timing and amount of our actual expenditures will be based on many factors, including the timing and success of our preclinical and clinical trials, our current and any future collaborations for our research and development programs, whether we choose to curtail some of our research or development activities and whether we achieve regulatory approval of any new drug candidates. We will retain broad discretion in determining how we will allocate the net proceeds from the sale of common stock under this prospectus.

DESCRIPTION OF CAPITAL STOCK

As of the date of this prospectus, our amended and restated certificate of incorporation, as amended, authorizes us to issue 73,500,000 shares of common stock, par value $0.0001 per share, and 7,500,000 shares of preferred stock, par value $0.0001 per share.

The following summary describes the material terms of our capital stock. The description of capital stock is qualified by reference to our amended and restated certificate of incorporation and our amended and restated bylaws, which are incorporated by reference as exhibits into the registration statement of which this prospectus is a part.

Common Stock

Voting. Common stockholders are entitled to one vote per share for the election of directors and on all other matters that require common stockholder approval.

Dividends and Other Distributions. Holders of our common stock are entitled to share in an equal amount per share in any dividends declared by our board of directors on the common stock and paid out of legally available assets.

Distribution on Dissolution. Subject to any preferential rights of any outstanding preferred stock, in the event of our liquidation, dissolution or winding up, holders of our common stock are entitled to share ratably in the assets remaining after payment of liabilities and the liquidation preferences of any outstanding preferred stock.

Other Rights. Our common stock does not carry any preemptive rights enabling a holder to subscribe for, or receive shares of, any class of our common stock or any other securities convertible into shares of any class of our common stock, or any redemption rights.

Preferred Stock

Under our amended and restated certificate of incorporation, as amended, our board of directors has the authority, without further action by stockholders, to designate up to 7,500,000 shares of preferred stock in one or more series and to fix the rights, preferences, privileges, qualifications and restrictions granted to or imposed upon the preferred stock, including dividend rights, conversion rights, voting rights, rights and terms of redemption, liquidation preference and sinking fund terms, any or all of which may be greater than the rights of our common stock.

The issuance of preferred stock could adversely affect the voting power of holders of common stock and reduce the likelihood that common stockholders will receive dividend payments and payments upon liquidation. The issuance could have the effect of decreasing the market price of the common stock. The issuance of preferred stock also could have the effect of delaying, deterring or preventing a change in control of us.

Anti-Takeover Provisions

Delaware Law. We are governed by the provisions of Section 203 of the Delaware General Corporation Law. In general, Section 203 prohibits a publicly held Delaware corporation from engaging in a “business combination” with an “interested stockholder” for a period of three years after the date of the transaction in which the person became an interested stockholder, unless (i) before the date that the person became an “interested stockholder,” our board of directors approved either the “business combination” or the transaction which makes the person an “interested stockholder,” (ii) the “interested stockholder” owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding for purposes of determining the number of shares outstanding (a) shares owned by persons who are directors and also officers and (b) shares owned by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer, or (iii) after the date that the person became an “interested stockholder,” the business combination is approved by our board of directors and the vote of at least 66 2/3% of our outstanding voting stock that is not owned by the “interested stockholder.” Generally, a “business combination” includes (A) any merger or consolidation involving the corporation and the interested stockholder, (B) any sale, transfer, pledge or other disposition involving the interested stockholder of 10% or more of the assets of the corporation, (C) subject to exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder, (D) any transaction involving the corporation that has the effect of increasing the proportionate share of its stock owned by the interested stockholder, or (E) the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation. An “interested stockholder” is a person who either owns 15% or more of our outstanding voting stock or, together with affiliates and associates, owns or, within three prior years, did own, 15% or more of our outstanding voting stock. The statute could have the effect of delaying, deferring or preventing a change in our control.

Bylaw and Certificate of Incorporation Provisions. Our amended and restated bylaws provide that special meetings of our stockholders may be called by our board of directors or President. Our amended and restated certificate of incorporation (i) specifies that the authorized number of directors shall be fixed by our board of directors in the manner provided by our amended and restated bylaws, which provide that the number of directors constituting our board of directors shall be fixed from time to time by resolution passed by a majority of our board of directors and (ii) does not include a provision for cumulative voting for directors. Under cumulative voting, a minority stockholder holding a sufficient percentage of a class of shares may be able to ensure the election of one or more directors. These and other provisions contained in our amended and restated certificate of incorporation and amended and restated bylaws could delay or discourage transactions involving an actual or potential change in control of us or our management, including transactions in which stockholders might otherwise receive a premium for their shares over then current prices. Such provisions could also limit the ability of stockholders to remove current management or approve transactions that stockholders may deem to be in their best interests and could adversely affect the price of our common stock.

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Computershare Trust Company, N.A.

Listing on The Nasdaq Global Select Market

Our common stock is listed on The Nasdaq Global Select Market under the symbol “ARNA.”

PLAN OF DISTRIBUTION

We may sell our common stock covered by this prospectus in any of three ways (or in any combination):

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to or through underwriters or dealers;

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directly to one or more purchasers; or

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through agents.

We may distribute the common stock:

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from time to time in one or more transactions at a fixed price or prices, which may be changed from time to time;

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at market prices prevailing at the time of sale;

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at prices related to the prevailing market prices; or

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at negotiated prices.

Each time we offer and sell shares of our common stock covered by this prospectus, we will provide a prospectus supplement or supplements that will describe the method of distribution and set forth the terms of the offering, including:

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the name or names of any underwriters, dealers or agents;

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the amounts of securities underwritten or purchased by each of them;

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the purchase price of the common stock and the proceeds we will receive from the sale;

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any option to purchase additional shares under which underwriters may purchase additional common stock from us;

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any underwriting discounts or commissions or agency fees and other items constituting underwriters’ or agents’ compensation;

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the public offering price of the common stock;

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any discounts, commissions or concessions allowed or reallowed or paid to dealers; and

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any securities exchange or market on which the common stock may be listed.

Any public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time. We may determine the price or other terms of the common stock offered under this prospectus by use of an electronic auction. We will describe how any auction will determine the price or any other terms, how potential investors may participate in the auction and the nature of the obligations of the underwriter, dealer or agent in the applicable prospectus supplement.

Underwriters or dealers may offer and sell the offered common stock from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. If underwriters or dealers are used in the sale of any common stock, the common stock will be acquired by the underwriters or dealers for their own account and may be resold from time to time in one or more transactions described above. The common stock may be either offered to the public through underwriting syndicates represented by managing underwriters, or directly by underwriters or dealers. Generally, the underwriters’ or dealers’ obligations to purchase the common stock will be subject to certain conditions precedent. The underwriters or dealers will be obligated to purchase all of the common stock if they purchase any of the common stock, unless otherwise specified in the prospectus supplement. We may use underwriters with whom we have a material relationship. We will describe the nature of any such relationship in the prospectus supplement, naming the underwriter.

We may sell the common stock through agents from time to time. The prospectus supplement will name any agent involved in the offer or sale of the common stock and any commissions we pay to them. Generally, any agent will be acting on a best efforts basis for the period of its appointment. We may authorize underwriters, dealers or agents to solicit offers by certain purchasers to purchase the common stock from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. The contracts will be subject only to those conditions set forth in the prospectus supplement, and the prospectus supplement will set forth any commissions we pay for solicitation of these contracts.

Agents, dealers and underwriters may be entitled to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, or to contribution with respect to payments which the agents, dealers or underwriters may be required to make in respect thereof. Agents, dealers and underwriters may be customers of, engage in transactions with, or perform services for us in the ordinary course of business.

To facilitate the offering of our common stock, underwriters participating in the offering may engage in overallotment, stabilizing transactions, short covering transactions and penalty bids in accordance with Regulation M under the Exchange Act. Overallotment involves the sale by the underwriters for the offering of more shares than we sold to them, which create a short position. This short sales position may involve either “covered” short sales or “naked” short sales. Covered short sales are short sales made in an amount not greater than the underwriters’ option to purchase additional shares for the offering. The underwriters may close out any covered short position either by exercising their overallotment option or by purchasing shares in the open market. To determine how they will close the covered short position, the underwriters will consider, among other things, the price of common stock available for purchase in the open market, as compared to the price at which they may purchase common stock through their overallotment option. Naked short sales are short sales in excess of the overallotment option. The underwriters must close out any naked short position by purchasing shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that, in the open market after pricing, there may be downward pressure on the price of the common stock that could adversely affect investors who purchase shares in the offering. Stabilizing transactions permit bids to purchase the underlying security for the purpose of fixing the price of the security so long as the stabilizing bids do not exceed a specified maximum. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the securities originally sold by the dealer are purchased in a covering transaction to cover short positions.

Any underwriters who are qualified market makers on The Nasdaq Global Select Market may engage in passive market making transactions in our common stock, preferred stock, warrants and debt securities, as applicable, on The Nasdaq Global Select Market in accordance with Rule 103 of Regulation M, during the business day prior to the pricing of the offering, before the commencement of offers or sales of the securities. Passive market makers must comply with applicable volume and price limitations and must be identified as passive market makers. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for such security; if all independent bids are lowered below the passive market maker’s bid, however, the passive market maker’s bid must then be lowered when certain purchase limits are exceeded.

Similar to other purchase transactions, an underwriter’s purchase to cover the syndicate short sales or to stabilize the market price of our common stock may have the effect of raising or maintaining the market price of our common stock or preventing or mitigating a decline in the market price of our common stock. As a result, the share price of our common stock may be higher than the price that might otherwise exist in the open market. The imposition of a penalty bid might also have an effect on the price of the common stock if it discourages resales of the shares.

Neither we nor the underwriters makes any representation or prediction as to the effect that the transactions described above may have on the price of our common stock. If such transactions are commenced, they may be discontinued without notice at any time.

LEGAL MATTERS

The validity of the securities being offered hereby will be passed upon for us by Cooley LLP, San Diego, California. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus supplement.

EXPERTS

The consolidated financial statements of Arena Pharmaceuticals, Inc. as of December 31, 2019 and 2018 and for each of the years in the three-year period ended December 31, 2019, and management’s assessment of the effectiveness of internal control over financial reporting as of December 31, 2019, have been incorporated by reference herein and in the registration statement in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing. The audit report covering the December 31, 2019 financial statements refers to a change to the method of accounting for revenue recognition as of January 1, 2018 due to the adoption of Accounting Standards Codification Topic 606, Revenue from Contracts with Customers, and for leases as of January 1, 2019 due to the adoption of Accounting Standards Codification Topic 842, Lease.

WHERE YOU CAN FIND MORE INFORMATION

This prospectus, which constitutes a part of the registration statement, does not contain all of the information set forth in the registration statement or the exhibits which are part of the registration statement. For further information with respect to us and the shares of common stock offered by this prospectus, we refer you to the registration statement and the exhibits filed as part of the registration statement. We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any document we file with the SEC at the SEC’s public reference room at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1.800.SEC.0330 for further information on the operation of the public reference room. Our SEC filings are also available to the public at the SEC’s website at http://www.sec.gov. We also maintain a website at http://www.arenapharm.com. The information contained in, or that can be accessed through, our website is not part of this prospectus.

INCORPORATION BY REFERENCE

The SEC allows us to “incorporate by reference” the information we file with it, which means that we can disclose important information to you by referring you to those documents instead of having to repeat the information in this prospectus. The information incorporated by reference is considered to be part of this prospectus, and later information that we file with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings we will make with the SEC under Sections 13(a), 13(c), 14, or 15(d) of the Exchange Act after the date of this prospectus (other than Current Reports or portions thereof furnished under Item 2.02 or Item 7.01 of Form8-K and exhibits filed on such form that are related to such items and other portions of documents that are furnished, but not filed, pursuant to applicable rules promulgated by the SEC) until the termination of the offering of the shares covered by this prospectus:

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our Annual Report onForm10-K for the year ended December 31, 2019, filed with the SEC on February 27, 2020;

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the information specifically incorporated by reference into our Annual Report on Form10-K for the year ended December 31, 2018 from our Definitive Proxy Statement onSchedule 14A for our 2019 Annual Meeting of Stockholders, filed with the SEC on April 30, 2019;

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our Current Report on Form8-K filed with the SEC onJanuary 13, 2020; and

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the description of our common stock contained in our registration statement onForm8-A filed with the SEC on July 26, 2000, including any amendments or reports filed for the purposes of updating this description.

You can request a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:

Arena Pharmaceuticals, Inc.

Attn: Investor Relations

6154 Nancy Ridge Drive

San Diego, California 92121

Telephone number: 858.453.7200

PROSPECTUS

LOGO

Up to $250,000,000

Common Stock

This sales agreement prospectus relates to the issuance and sale of shares of our common stock having an aggregate offering price of up to $250,000,000 from time to time through our sales agents, Credit Suisse Securities (USA) LLC, SVB Leerink LLC and Cantor Fitzgerald & Co., collectively, the Sales Agents. These sales, if any, will be made pursuant to the terms of a Sales Agreement, or the Sales Agreement among us and the Sales Agents, dated February 27, 2020, which is filed with the Securities and Exchange Commission, or the SEC, as an exhibit to the registration statement of which this prospectus is part.

Our common stock is traded on The Nasdaq Global Select Market under the symbol “ARNA.” On February 25, 2020, the closing sale price of our common stock on The Nasdaq Global Select Market was $47.79 per share.

Sales of shares of our common stock under this prospectus, if any, may be made by any method deemed to be an “at the market offering” as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended, or the Securities Act. The Sales Agents are not required to sell any specific number or dollar amount of shares of our common stock. Each of the Sales Agents has agreed to use its commercially reasonable efforts to sell on our behalf all of the shares of common stock requested to be sold by us, consistent with its normal trading and sales practices, on mutually agreed terms among the Sales Agents and us. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.

The Sales Agents will be entitled to compensation under the terms of the Sales Agreement at a commission rate of up to 3.0% of the gross sales price per share sold. The net proceeds from any sales under this prospectus will be used as described under “Use of Proceeds.” The proceeds we receive from sales of our common stock, if any, will depend on the number of shares actually sold and the offering price of such shares.

In connection with the sale of common stock on our behalf, each of the Sales Agents will be deemed to be an “underwriter” within the meaning of the Securities Act, and the compensation of the Sales Agents will be deemed to be underwriting commissions or discounts. We have agreed to provide indemnification and contribution to the Sales Agents with respect to certain liabilities, including liabilities under the Securities Act.

Investing in our common stock involves a high degree of risk. You should review carefully and consider the risks and uncertainties referenced under the heading “Risk Factors” beginning on pageSA-3 of this prospectus and the risk factors contained in other documents incorporated by reference in this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus. Any representation to the contrary is a criminal offense.


Credit Suisse		SVB Leerink		Cantor

The date of this prospectus is February 27, 2020.

TABLE OF CONTENTS


	Page
About this Prospectus		SA-i
Summary		SA-1
Risk Factors		SA-3
Special Note Regarding Forward-Looking Statements		SA-4
Use of Proceeds		SA-5
Dilution		SA-6
Plan of Distribution		SA-7
Legal Matters		SA-8
Experts		SA-8
Where You Can Find More Information		SA-8
Incorporation by Reference		SA-8

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on FormS-3 that we filed with the SEC using a “shelf” registration process as a “well-known seasoned issuer,” as defined in Rule 405 under the Securities Act. Under this shelf registration statement, we may offer shares of our common stock having an aggregate offering price of up to $250,000,000 under this prospectus at prices and on terms to be determined by market conditions at the time of offering.

This prospectus and the documents incorporated into this prospectus by reference include important information about us, the shares being offered and other information you should know before investing in our common stock. To the extent there is a conflict between the information contained in this prospectus, on the one hand, and the information contained in any document incorporated by reference into this prospectus that was filed with the SEC before the date of this prospectus, on the other hand, you should rely on the information in this prospectus. However, if any statement in one of these documents is inconsistent with a statement in another document having a later date—for example, a document incorporated by reference in this prospectus—the statement in the document having the later date modifies or supersedes the earlier statement as our business, financial condition, results of operations and prospects may have changed since the earlier dates.

We further note that the representations, warranties and covenants made by us in any agreement, including the Sales Agreement, that is filed as an exhibit to any document that is incorporated by reference herein were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreement, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

We have not, and the Sales Agents have not, authorized anyone to provide you with information that is in addition to or different from that contained or incorporated by reference into this prospectus. We and each of the Sales Agents take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. Neither we nor any of the Sales Agents are offering to sell these securities in any jurisdiction where the offer or sale is not permitted. You should not assume that the information contained or incorporated by reference in this prospectus is accurate as of any date other than as of the date of this prospectus or in the case of the documents incorporated by reference, the date of such documents regardless of the time of delivery of this prospectus or any sale of our common stock. Our business, financial conditions, liquidity, results of operations and prospects may have changed since those dates. You should read this prospectus, the documents incorporated by reference into this prospectus, and any free writing prospectus that we may authorize for use in connection with this offering, in their entirety before making an investment decision. You should also read and consider the information in the documents to which we have referred you in the sections of this prospectus titled “Where You Can Find More Information” and “Incorporation by Reference.”

SA-i

SUMMARY

The following summary highlights information contained elsewhere or incorporated by reference in this prospectus. This summary does not contain all the information that may be important to purchasers of our common stock. Prospective purchasers of our common stock should carefully read and consider this entire prospectus, all documents incorporated by reference herein, and any free writing prospectus we authorize for use in connection with this offering.

Company Overview

Company Information

SA-1

The Offering


Common stock offered by us		Shares of our common stock having an aggregate offering price of up to $250,000,000.

Plan of Distribution		“At-the-market offering” that may be made from time to time through the Sales Agents, Credit Suisse Securities (USA) LLC, SVB Leerink LLC and Cantor Fitzgerald & Co. See “Plan of Distribution” beginning onpage SA-7.

Use of Proceeds		We currently intend to use the net proceeds from this offering for the clinical and preclinical development of drug candidates, for general corporate purposes, including working capital and costs associated with manufacturing services, and for capital expenditures. See the section entitled “Use of Proceeds” onpage SA-5.

Risk Factors		Investing in our common stock involves a high degree of risk. See the information contained in or incorporated by reference under the heading “Risk Factors” in this prospectus and in the documents incorporated by reference into this prospectus and any free writing prospectus that we have authorized for use in connection with this offering.

Nasdaq Global Select Market listing		Our common stock is listed on The Nasdaq Global Select Market under the symbol “ARNA.”

SA-2

RISK FACTORS

Investing in our common stock involves a high degree of risk. Before deciding whether to invest in our common stock, you should consider carefully the risks and uncertainties described below and under the heading “Risk Factors” contained in our most recent Annual Report on Form10-K and any subsequent Quarterly Reports on Form10-Q, which are incorporated by reference into this prospectus in their entirety, as updated or superseded by the risks and uncertainties described under similar headings in the other documents that are filed after the date hereof and incorporated by reference into this prospectus, together with the other information in this prospectus, the documents incorporated by reference and any free writing prospectus that we may authorize for use in connection with this offering. The risks described in these documents are not the only ones we face, but those that we consider to be material. There may be other unknown or unpredictable economic, business, competitive, regulatory or other factors that could have material adverse effects on our future results. Past financial performance may not be a reliable indicator of future performance, and historical trends should not be used to anticipate results or trends in future periods. If any of these risks actually occur, our business, financial condition, results of operations or cash flow could be seriously harmed. This could cause the trading price of our common stock to decline, resulting in a loss of all or part of your investment. Please also read carefully the section below titled “Special Note Regarding Forward-Looking Statements.”

Additional Risks Related to This Offering

Management will have broad discretion as to the use of the proceeds from this offering, and may not use the proceeds effectively.

Because we have not designated the amount of net proceeds from this offering to be used for any particular purpose, our management will have broad discretion as to the application of the net proceeds from this offering and could use them for purposes other than those contemplated at the time of the offering. Our management may use the net proceeds for corporate purposes that may not improve our financial condition or market value.

You may experience immediate and substantial dilution.

The offering price per share in this offering may exceed the net tangible book value per share of our common stock outstanding prior to this offering. Assuming that an aggregate of 5,231,219 shares of our common stock are sold at a price of $47.79 per share, the last reported sale price of our common stock on The Nasdaq Global Select Market on February 25, 2020, for aggregate gross proceeds of $250.0 million, and after deducting estimated commissions and offering expenses payable by us, you would experience immediate dilution of $24.03 per share, representing the difference between our as adjusted net tangible book value per share as of December 31, 2019 after giving effect to this offering and the assumed public offering price. The exercise of outstanding stock options or settlement of restricted stock units or performance restricted stock units may result in further dilution of your investment. See the section titled “Dilution” below for a more detailed illustration of the dilution you may incur if you participate in this offering.

You may experience future dilution as a result of future equity offerings.

In order to raise additional capital, we expect to in the future offer additional shares of common stock or other securities convertible into or exchangeable for our shares of common stock. We cannot assure you that we will be able to sell shares or other securities in any other offering at a price per share that is equal to or greater than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders. The price per share at which we sell additional shares of common stock or other securities convertible into or exchangeable for our shares of common stock in future transactions may be higher or lower than the price per share in this offering.

SA-3

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus or any free writing prospectus that we authorize for use in connection with this offering, including the documents that we incorporate by reference herein and therein, contain “forward-looking statements” within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act. These forward-looking statements can generally be identified as such because the context of the statement will include words such as “may,” “will,” “intend,” “plan,” “believe,” “anticipate,” “expect,” “estimate,” “predict,” “potential,” “continue,” “likely,” “unlikely” or “opportunity,” the negative of these words or words of similar import. Similarly, statements that describe our future plans, strategies, intentions, expectations, objectives, goals or prospects are also forward-looking statements. Discussions containing these forward-looking statements may be found, among other places, in the “Business” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections incorporated by reference from our most recent Annual Report on Form10-K and our Quarterly Reports on Form10-Q for the quarterly periods ended subsequent to our filing of such Annual Report on Form10-K, as well as any amendments thereto reflected in subsequent filings with the SEC. These forward-looking statements are based largely on our expectations and projections about future events and future trends affecting our business, and are subject to risks and uncertainties that could cause actual results to differ materially from those anticipated in the forward-looking statements. The risks and uncertainties include, among others, those noted in “Risk Factors” above and in any applicable prospectus supplement or free writing prospectus, and those included in the documents that we incorporate by reference herein and therein. In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date the statement is made, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and you are cautioned not to unduly rely upon these statements.

SA-4

USE OF PROCEEDS

We may issue and sell shares of our common stock having aggregate sales proceeds of up to $250.0 million from time to time. Because there is no minimum offering amount required as a condition to close this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time.

We currently intend to use the net proceeds from this offering for the clinical and preclinical development of drug candidates, for general corporate purposes, including working capital and costs associated with manufacturing services, and for capital expenditures. We may also use a portion of the net proceeds to acquire drugs or drug candidates, technologies, businesses or other assets, although we have no current plans, commitments or agreements to do so as of the date of this prospectus. The timing and amount of our actual expenditures will be based on many factors, including the timing and success of our preclinical and clinical trials, our current and any future collaborations for our research and development programs, whether we choose to curtail some of our research or development activities and whether we achieve regulatory approval of any new drug candidates. We will retain broad discretion in determining how we will allocate the net proceeds from the sale of common stock under this prospectus.

SA-5

DILUTION

Our net tangible book value as of December 31, 2019 was approximately $1,071.5 million, or $21.36 per share. Net tangible book value per share is determined by dividing our total tangible assets, less total liabilities, by the number of shares of our common stock outstanding as of December 31, 2019. Dilution with respect to net tangible book value per share represents the difference between the amount per share paid by purchasers of shares of common stock in this offering and the net tangible book value per share of our common stock immediately after this offering.

After giving effect to the assumed sale of 5,231,219 shares of our common stock in this offering at an assumed public offering price of $47.79 per share, the last reported sale price of our common stock on The Nasdaq Global Select Market on February 25, 2020, and after deducting estimated commissions and offering expenses payable by us, our as adjusted net tangible book value as of December 31, 2019 would have been approximately $1,316.3 million, or $23.76 per share. This represents an immediate increase in net tangible book value of $2.40 per share to existing stockholders and immediate dilution of $24.03 per share to investors purchasing our common stock in this offering at the assumed public offering price. The following table illustrates this dilution on a per share basis:


Assumed public offering price per share			$	47.79
Net tangible book value per share of as December 31, 2019	$	21.36
Increase in net tangible book value per share attributable to this offering	$	2.40
As adjusted net tangible book value per share as of December 31, 2019, after giving effect to this offering			$	23.76
Dilution per share to new investors purchasing our common stock in this offering			$	24.03

The table above assumes for illustrative purposes that an aggregate of 5,231,219 shares of our common stock are sold during the term of the Sales Agreement at a price of $47.79 per share, the last reported sale price of our common stock on The Nasdaq Global Select Market on February 25, 2020, for aggregate gross proceeds of approximately $250.0 million. The shares subject to the Sales Agreement may be sold from time to time at various prices. An increase of $1.00 per share in the price at which the shares are sold from the assumed public offering price of $47.79 per share shown in the table above, assuming all of our common stock in the aggregate amount of $250.0 million during the term of the Sales Agreement is sold at that price, would increase our as adjusted net tangible book value per share after the offering to $23.80 per share and would increase the dilution in net tangible book value per share to new investors in this offering to $24.99 per share, after deducting estimated commissions and offering expenses payable by us. A decrease of $1.00 per share in the price at which the shares are sold from the assumed public offering price of $47.79 per share shown in the table above, assuming all of our common stock in the aggregate amount of $250.0 million during the term of the Sales Agreement is sold at that price, would decrease our as adjusted net tangible book value per share after the offering to $23.71 per share and would decrease the dilution in net tangible book value per share to new investors in this offering to $23.08 per share, after deducting estimated commissions and offering expenses payable by us. This information is supplied for illustrative purposes only and may differ based on the actual public offering price and the actual number of shares offered.

The number of shares of our common stock to be outstanding after this offering is based on 50,170,953 shares of our common stock outstanding as of December 31, 2019 and excludes, as of such date:

•

8,535,139 shares of common stock issuable upon the exercise of outstanding stock options at a weighted-average exercise price of $34.31 per share;

•

23,564 shares of common stock issuable pursuant to restricted stock units;

•

421,220 shares of common stock issuable pursuant to performance restricted stock units, upon achieving 200% of target achievement for such awards;

•

3,024,755 shares of common stock available for future issuance under our Amended and Restated 2017 Long-Term Incentive Plan; and

•

1,000,000 shares of common stock available for future issuance under our 2019 Employee Stock Purchase Plan.

To the extent that options, restricted stock units or performance restricted stock units outstanding as of December 31, 2019 have been or may be exercised or settle, as applicable, or other shares issued, investors purchasing our common stock in this offering may experience further dilution. In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that additional capital is raised through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

SA-6

PLAN OF DISTRIBUTION

We entered into the Sales Agreement with the Sales Agents on February 27, 2020, under which we may offer and sell up to $250,000,000 of shares of our common stock from time to time through the Sales Agents, acting as agents. Sales of shares of our common stock, if any, under this prospectus may be made at market prices by any method deemed to be an “at the market offering” as defined in Rule 415(a)(4) under the Securities Act, including, without limitation, sales made directly on or through The Nasdaq Global Select Market or any other existing trading market for our common stock and/or any other method permitted by law.

We may instruct the Sales Agents not to sell our common stock if the sales cannot be effected at or above the price designated by us from time to time. We or the Sales Agents may suspend the offering of common stock upon notice and subject to other conditions.

We will pay the Sales Agents commissions, in cash, for their services for acting as a Sales Agent in the sale of our common stock. The Sales Agents will be entitled to compensation at a fixed commission rate of up to 3.0% of the gross sales price per share sold. We have also agreed to reimburse the Sales Agents for certain specified expenses, including the fees and disbursements of their legal counsel, in an amount not to exceed $50,000. We estimate that the total expenses for the offering, excluding compensation and reimbursement payable to the Sales Agents under the terms of the Sales Agreement, will be approximately $200,000. Because there is no minimum offering amount required as a condition to close this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time.

Settlement for sales of our common stock will occur on the second trading day following the date on which any sales are made, or on some other date that is agreed upon by us and the Sales Agents in connection with a particular transaction, in return for payment of the net proceeds to us. Sales of our common stock as contemplated in this prospectus will be settled through the facilities of The Depository Trust Company or by such other means as we and the Sales Agents may agree upon. There is no arrangement for funds to be received in an escrow, trust or similar arrangement.

The Sales Agents will use their commercially reasonable efforts, consistent with their normal sales and trading practices, to solicit offers to purchase shares of our common stock under the terms and subject to the conditions set forth in the Sales Agreement. In connection with the sale of shares of our common stock on our behalf, each of the Sales Agents may be deemed to be an “underwriter” within the meaning of the Securities Act and the compensation of the Sales Agents may be deemed to be underwriting commissions or discounts. We have agreed to provide indemnification and contribution to the Sales Agents against certain civil liabilities, including liabilities under the Securities Act.

The offering pursuant to the Sales Agreement will terminate upon the termination of the Sales Agreement as permitted therein. We and each Sales Agent (with respect to itself) may terminate the Sales Agreement at any time upon five days’ prior notice.

The Sales Agents and their respective affiliates may provide various investment banking and other financial services for us and our affiliates, for which services they may in the future receive customary fees. To the extent required by Regulation M, the Sales Agents will not engage in any market making activities involving our common stock while the offering is ongoing under this prospectus.

This summary of the material provisions of the Sales Agreement does not purport to be a complete statement of its terms and conditions. A copy of the Sales Agreement is filed as an exhibit to the registration statement of which this prospectus forms a part and is incorporated by reference in this prospectus.

This prospectus in electronic format may be made available on a website maintained by each of the Sales Agents and the Sales Agents may distribute this prospectus electronically.

SA-7

LEGAL MATTERS

Cooley LLP, San Diego, California, has passed upon the validity of the common stock offered by this prospectus. Latham & Watkins LLP is counsel for the Sales Agents in connection with this offering.

EXPERTS

WHERE YOU CAN FIND MORE INFORMATION

INCORPORATION BY REFERENCE

•

our Annual Report onForm10-K for the year ended December 31, 2019, filed with the SEC on February 27, 2020;

•

our Current Report on Form8-K filed with the SEC onJanuary 13, 2020; and

•

You can request a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:

Arena Pharmaceuticals, Inc.

Attn: Investor Relations

6154 Nancy Ridge Drive

San Diego, California 92121

Telephone number: 858.453.7200

SA-8

LOGO

Up to $250,000,000

Common Stock

PROSPECTUS


Credit Suisse		SVB Leerink		Cantor

February 27, 2020

PART II

INFORMATION NOT REQUIRED IN THE PROSPECTUS

Item 14.

Other Expenses of Issuance and Distribution.

The following sets forth the estimated costs and expenses, all of which shall be borne by the registrant, in connection with the offering of the securities pursuant to this registration statement:


Registration fee	$	(1	)
Legal fees and expenses		(2	)
Accounting fees and expenses		(2	)
Printer fees and expenses		(2	)
Miscellaneous fees and expenses		(2	)
Total	$	(2	)

(1)

In accordance with Rules 456(b) and 457(r) under the Securities Act of 1933, as amended, or the Securities Act, the registrant is deferring payment of all applicable registration fees other than the fees due in connection with the $250,000,000 of our common stock that may be issued and sold from time to time under the sales agreement with Credit Suisse Securities (USA) LLC, SVB Leerink LLC and Cantor Fitzgerald & Co.

(2)	Since an indeterminate amount of securities is covered by this registration statement, the expenses in connection with the issuance and distribution of the securities are not currently determinable

Item 15.

Indemnification of Directors and Officers.

The registrant’s Certificate of Incorporation and Bylaws provide for indemnification of the registrant’s directors and officers to the fullest extent permitted by law. Insofar as indemnification for liabilities under the Securities Act may be permitted to directors, officers or controlling persons of the registrant pursuant to the registrant’s Certificate of Incorporation, Bylaws and the Delaware General Corporation Law, or DGCL, the registrant has been informed that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

Section 102(b)(7) of the DGCL provides that a certificate of incorporation may include a provision which eliminates or limits the personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except for liability (i) for any breach of the director’s duty of loyalty to the company or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the DGCL, relating to prohibited dividends or distributions or the repurchase or redemption of stock or (iv) for any transaction from which the director derives an improper personal benefit. The registrant’s Certificate of Incorporation includes such a provision. As a result of this provision, the registrant and its stockholders may be unable to obtain monetary damages from a director for breach of his or her duty of care.

As permitted under the DGCL, the registrant has entered into indemnification agreements with each of its directors and executive officers that require the registrant to indemnify such persons against any and all expenses (including attorneys’, witness or other professional fees), and unless in connection with a proceeding by or in the right of the registrant, any and all judgments, fines and amounts paid in settlement, actually and reasonably incurred by such persons or on such persons’ behalf in connection with any proceeding, whether actual or threatened, to which any such person may be involved as a party or otherwise by reason of the fact that such person is or was a director or an executive officer of the registrant or is or was serving at the request of the registrant as a director, officer, employee, agent or fiduciary of another enterprise, provided such person acted in good faith and in a manner such person reasonably believed to be in or not opposed to the best interests of the registrant and, with respect to any criminal proceeding, had no reasonable cause to believe such person’s conduct was unlawful. Under these agreements, the registrant is not required to provide indemnification for certain matters, including:

•

indemnification beyond that permitted by applicable law;

II-1

•

except as provided in the indemnification agreements, an accounting of profits made from the purchase and sale (or sale and purchase) by such director or executive officer of securities of the registrant within the meaning of Section 16(b) of the Securities Exchange Act of 1934, as amended, or the Exchange Act, or similar provisions of state statutory law or common law;

•

except as provided in the indemnification agreements, any reimbursement of the registrant by such director or executive officer of any bonus or other incentive-based or equity-based compensation or of any profits realized by such director or executive officer from the sale of securities of the registrant, as required in each case under the Exchange Act; or

•

except as provided in the indemnification agreements, in connection with any proceeding initiated by such director or executive officer, unless (i) the registrant’s Board of Directors authorized the proceeding prior to its initiation or (ii) the registrant provides the indemnification, in its sole discretion, pursuant to the powers vested in the registrant under applicable law.

The indemnification agreements also set forth certain procedures, presumptions and remedies that will apply in the event of a claim for indemnification thereunder.

Item 16.

Exhibits.


Exhibit Number		Description of Document

1.1*		Form of Underwriting Agreement

1.2		Sales Agreement, dated February 27, 2020, by and among Arena, Credit Suisse Securities (USA) LLC, SVB Leerink LLC and Cantor Fitzgerald & Co.

4.1		Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit 3.1 to Arena’s Quarterly Report on Form10-Q for the quarter ended June 30, 2002, filed with the Securities and Exchange Commission on August 14, 2002, Commission File No. 000-31161)

4.2		Certificate of Amendment of the Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit 4.2 to Arena’s registration statement on FormS-8, filed with the Securities and Exchange Commission on June 28, 2006, Commission File No. 333-135398)

4.3		Certificate of Amendment No. 2 of the Fifth Amended and Restated Certificate of Incorporation of Arena, as amended (incorporated by reference to Exhibit 4.3 to Arena’s registration statement on FormS-8, filed with the Securities and Exchange Commission on June 30, 2009, Commission File No. 333-160329)

4.4		Certificate of Amendment No. 3 of the Fifth Amended and Restated Certificate of Incorporation of Arena, as amended (incorporated by reference to Exhibit 3.4 to Arena’s registration statement on FormS-8, filed with the Securities and Exchange Commission on June 20, 2012, Commission File No. 333-182238)

4.5		Certificate of Amendment No. 4 of the Fifth Amended and Restated Certificate of Incorporation of Arena, as amended (incorporated by reference to Exhibit 3.1 to Arena’s Current Report on Form8-K, filed with the Securities and Exchange Commission on June 15, 2017, Commission File No. 000-31161)

4.6		Amended and Restated Bylaws of Arena (incorporated by reference to Exhibit 3.1 to Arena’s Current Report on Form8-K, filed with the Securities and Exchange Commission on October 9, 2014, Commission File No. 000-31161)

4.7		Form of common stock certificate (incorporated by reference to Exhibit 4.7 to Arena’s registration statement on FormS-8, filed with the Securities and Exchange Commission on June 22, 2017, Commission File No. 333-218905)

5.1		Opinion of Cooley LLP

23.1		Consent of Cooley LLP (included in Exhibit 5.1 to this filing)

23.2		Consent of Independent Registered Public Accounting Firm

24.1		Power of Attorney (included on the signature page hereto)

*	To be filed by amendment or by a report filed under the Securities Exchange Act of 1934, as amended, and incorporated herein by reference.

II-2

Item 17.

Undertakings.

The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b); and

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however, that the undertakings set forth in paragraphs (1)(i), (1)(ii) and (1)(iii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in the registration statement or is contained in a form of prospectus filed pursuant to Rule 424(b) that is a part of the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4) That, for the purpose of determining liability under the Securities Act to any purchaser:

(i) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(ii) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

(5) That, for the purpose of determining liability of the registrant under the Securities Act to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

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(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

(6) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the registrant’s annual report pursuant to Section 13(a) or 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers, and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer, or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer, or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on FormS-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of San Diego, State of California, on February 27, 2020.


ARENA PHARMACEUTICALS, INC.

By:		/s/ Amit D. Munshi
		Amit D. Munshi President and Chief Executive Officer

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Amit D. Munshi as his or her true and lawfulattorney-in-fact and agent, with full power of substitution and resubstitution, for him or her and in his or her name, place, and stead, in any and all capacities, to sign any and all post-effective amendments (including exhibits thereto and other documents in connection therewith) to this registration statement, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto saidattorney-in-fact and agent, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that saidattorney-in-fact and agent, or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the dates indicated.


Signatures		Title	Date

By:	/s/ Amit D. Munshi	President and Chief Executive Officer and Director	February 27, 2020
	Amit D. Munshi	(principal executive officer)

By:	/s/ Kevin R. Lind	Executive Vice President and Chief Financial Officer	February 27, 2020
	Kevin R. Lind	(principal financial officer and principal accounting officer)

By:	/s/ Jayson Dallas	Director	February 27, 2020
	Jayson Dallas, M.D.

By:	/s/ Oliver Fetzer	Director	February 27, 2020
	Oliver Fetzer, Ph.D.

By:	/s/ Kieran T. Gallahue	Director	February 27, 2020
	Kieran T. Gallahue

By:	/s/ Jennifer Jarrett	Director	February 27, 2020
	Jennifer Jarrett

By:	/s/ Garry A. Neil	Director	February 27, 2020
	Garry A. Neil, M.D.

By:	/s/ Tina S. Nova	Director	February 27, 2020
	Tina S. Nova, Ph.D.

By:	/s/ Manmeet S. Soni	Director	February 27, 2020
	Manmeet S. Soni

By:	/s/ Randall E. Woods	Director	February 27, 2020
	Randall E. Woods

Large accelerated filer

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Non-accelerated filer

Smaller reporting company

Emerging growth company