AMLN Amylin Pharmaceuticals, Inc. (MM)

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The Information in this preliminary prospectus supplement is not complete and may be changed. A registration statement relating to these securities has been declared effective by the Securities and Exchange Commission. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell these securities, and we are not soliciting offers to buy these securities, in any state or other jurisdiction where the offer or sale is not permitted.

 

Filed Pursuant to Rule 424(b)(5)
File No. 333-179964

SUBJECT TO COMPLETION, DATED MARCH 7, 2012

PRELIMINARY PROSPECTUS SUPPLEMENT TO PROSPECTUS DATED MARCH 7, 2012

13,000,000 Shares

Common Stock

We are offering             shares of our common stock as described in this prospectus supplement and the accompanying prospectus.

Our common stock is listed on The NASDAQ Global Select Market under the symbol “AMLN” The closing price of our common stock on The NASDAQ Global Select Market on March 6, 2012 was $16.02 per share.

The underwriter has a thirty-day option to purchase a maximum of 1,950,000 additional shares.

Investing in our common stock involves a high degree of risk. See the risks set forth under the heading “Risk Factors” on page S-4 of this prospectus supplement and the documents incorporated by reference into this prospectus supplement.

The underwriter has agreed to purchase the shares of common stock from us at a price of $         per share, which will result in approximately $         million of net proceeds to us, before deducting estimated offering expenses payable by us. The underwriter may offer the shares in transactions on The NASDAQ Global Select Market, in the over-the-counter market or through negotiated transactions at market prices or at negotiated prices. See “Underwriting.”

Delivery of the shares of common stock will be made on or about March     , 2012.

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.

Credit Suisse

The date of this prospectus supplement is March     , 2012.

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Neither we nor the underwriter have authorized anyone to provide you with information different from that contained in or incorporated by reference into this prospectus supplement, the accompanying prospectus and in any free writing prospectus that we have authorized for use in connection with this offering. We take no responsibility for, and can provide no assurance as to the reliability of, any information that others may give you. If anyone provides you with different or inconsistent information, you should not rely on it. We are not, and the underwriter is not, making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus supplement, the accompanying prospectus, the documents incorporated by reference in this prospectus supplement and the accompanying prospectus, and in any free writing prospectus that we have authorized for use in connection with this offering, is accurate only as of the date of those respective documents. Our business, financial condition, results of operations and prospects may have changed since those dates. You should read this prospectus supplement, the accompanying prospectus, the documents incorporated by reference in this prospectus supplement and the accompanying prospectus, and any free writing prospectus that we have authorized 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 supplement entitled “Where You Can Find More Information” and “Incorporation of Certain Information by Reference.”

 

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document is in two parts. The first part is this prospectus supplement, which describes the terms of this offering of common stock and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. The second part, the accompanying prospectus dated March 7, 2012, including the documents incorporated by reference therein, provides more general information about the securities we may offer from time to time, some of which may not apply to the offering described in this prospectus supplement. Generally, when we refer to this prospectus, we are referring to both parts of this document combined. To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in the accompanying prospectus or in any document incorporated by reference that was filed with the Securities and Exchange Commission, or SEC, before the date of this prospectus supplement, on the other hand, you should rely on the information in this prospectus supplement. 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 the accompanying prospectus—the statement in the document having the later date modifies or supersedes the earlier statement.

Unless otherwise mentioned or unless the context requires otherwise, all references in this prospectus supplement to “Amylin,” “we,” “us,” and “our” are to Amylin Pharmaceuticals, Inc. and its subsidiaries.

This prospectus supplement, the accompanying prospectus and the information incorporated herein and therein by reference may include trademarks, service marks and trade names owned by us or other companies. All trademarks, service marks and trade names included or incorporated by reference into this prospectus supplement or the accompanying prospectus are the property of their respective owners.

 

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RISK FACTORS

Investing in our common stock involves a high degree of risk. Our business, prospects, financial condition or operating results could be materially adversely affected by the risks identified below, as well as other risks not currently known to us or that we currently consider immaterial. The trading price of our common stock could decline due to any of these risks, and you may lose all or part of your investment. In assessing the risks described below, you should also refer to the information contained in our Annual Report on Form 10-K for the year ended December 31, 2011 and other documents which are incorporated by reference in this prospectus supplement and the accompanying prospectus in their entirety, and other documents that we file from time to time with the SEC.

Risks Related to this Offering

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

Our management will have broad discretion in the application of the net proceeds from this offering and could spend the proceeds in ways that do not improve our results of operations or enhance the value of our common stock. Our failure to apply these funds effectively could have a material adverse effect on our business, delay the development of our product candidates and cause the price of our common stock to decline.

If you purchase the common stock sold in this offering, you will experience immediate and substantial dilution in your investment. You will experience further dilution if we issue additional equity securities in future fundraising transactions.

Since the price per share of our common stock being offered is substantially higher than the net tangible book value per share of our common stock, you will suffer substantial dilution with respect to the net tangible book value of the common stock you purchase in this offering. Based on the public offering price of $         per share and our net tangible book value as of December 31, 2011, if you purchase shares of common stock in this offering, you will suffer immediate and substantial dilution of $         per share with respect to the net tangible book value of the common stock. See the section entitled “Dilution” for a more detailed discussion of the dilution you will incur if you purchase common stock in this offering.

In addition, we have a significant number of stock options outstanding and unvested restricted stock units. To the extent that outstanding stock options have been or may be exercised, restricted stock units vest 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 or result in downward pressure on the price of our common stock.

 

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying prospectus, the documents we have filed with the SEC that are incorporated herein by reference and any free writing prospectus prepared by or on behalf of us or to which we have referred you contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act. These statements are based on our current expectations, assumptions, estimates and projections about our business and our industry, and involve known and unknown risks, uncertainties and other factors that may cause our results, levels of activity, performance or achievement to be materially different from any future results, levels of activity, performance or achievements expressed or implied by the forward-looking statements.

In some cases, you can identify forward-looking statements by terms such as “anticipate,” “believe,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “will,” “would” and similar expressions intended to identify forward-looking statements. While we believe that we have a reasonable basis for each forward-looking statement, we caution you that these statements are based on a combination of facts and factors currently known by us and our projections of the future, about which we cannot be certain. We discuss many of these risks, uncertainties and other factors in greater detail under the sections captioned “Risk Factors” contained in this prospectus supplement and in our Annual Report on Form 10-K for the year ended December 31, 2011 and other filings with the SEC. Given these risks, uncertainties and other factors, you should not place undue reliance on these forward-looking statements. Also, these forward-looking statements represent our estimates and assumptions only as of the date such forward-looking statements are made. You should read carefully both this prospectus supplement and the accompanying prospectus, together with the information incorporated herein by reference as described under the heading “Incorporation of Certain Information by Reference” in this prospectus supplement, completely and with the understanding that our actual future results may be materially different from what we expect. We hereby qualify all of our forward-looking statements by these cautionary statements.

Except as required by law, we assume no obligation to update these forward-looking statements publicly, or to update the reasons actual results could differ materially from those anticipated in these forward-looking statements, even if new information becomes available in the future.

 

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USE OF PROCEEDS

We estimate that the net proceeds from the sale of the             shares of common stock that we are offering will be approximately $         million, or approximately $         million if the underwriter exercises in full its option to purchase up to             additional shares of common stock, after deducting the estimated underwriting discounts and commissions and estimated offering expenses payable by us.

We intend to use the net proceeds from this offering primarily for expenses related to our commercialization of BYDUREON, as well as for general corporate purposes which may include research and development expenses, capital expenditures, working capital and general administrative expenses. We may also use a portion of the net proceeds to acquire or invest in complementary businesses, products and technologies. Although we have no specific agreements, commitments or understandings with respect to any acquisition, we evaluate acquisition opportunities and engage in related discussions with other companies from time to time.

The amounts and timing of these expenditures will depend on a number of factors, such as the level of our commercialization efforts, the timing and progress of our research and development efforts, the timing and progress of any partnering efforts, technological advances and the competitive environment for our product candidates. As of the date of this prospectus supplement, we cannot specify with certainty all of the particular uses for the net proceeds to us from this offering. Accordingly, our management will have broad discretion in the application of these proceeds. Pending application of the net proceeds as described above, we intend to temporarily invest the proceeds in short term, interest-bearing instruments.

 

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DILUTION

Our net tangible book value (deficit) as of December 31, 2011 was approximately $(774.3) million, or $(5.29) per share. Net tangible book value (deficit) 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, 2011. Dilution with respect to net tangible book value (deficit) per share represents the difference between the amount per share paid by purchasers of shares of common stock in this public offering and the net tangible book value (deficit) per share of our common stock immediately after this public offering.

After giving effect to the sale of             shares of our common stock in this offering at the public offering price of $             per share and after deducting the estimated underwriting discounts and commissions and estimated offering expenses payable by us, our as adjusted net tangible book value (deficit) as of December 31, 2011 would have been approximately $             million, or $             per share. This represents an immediate increase in net tangible book value of $             per share to existing stockholders and immediate dilution of $             per share to investors purchasing our common stock in this offering at the public offering price.

The following table illustrates this dilution on a per share basis:

 

Public offering price per share						$
Net tangible book value (deficit) per share as of December 31, 2011		$	(5.29	)
Increase in net tangible book value per share attributable to new investors purchasing our common stock in this offering
As adjusted net tangible book value (deficit) per share on December 31, 2011, after giving effect to this offering
Dilution per share to new investors purchasing our common stock in this offering						$

If the underwriter exercises in full its option to purchase up to             additional shares of common stock at the public offering price of $         per share, the as adjusted net tangible book value (deficit) after this offering would have been $         per share, representing an increase in net tangible book value of $         per share to existing stockholders and immediate dilution of $         per share to investors purchasing our common stock in this offering at the public offering price.

The above discussion and table are based on 146,288,925 shares outstanding as of December 31, 2011, and exclude as of that date:

 

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17,540,000 shares of common stock issuable upon the exercise of stock options outstanding under our equity incentive plans at a weighted average exercise price of $22.84 per share, 1,364,000 shares of common stock subject to restricted stock units outstanding under our equity incentive plans and 27,289,000 additional shares of common stock reserved for future issuance under our equity incentive plans;

 

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547,000 reserved for future issuance under our employee stock purchase plan; and

 

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9,415,740 shares of common stock issuable upon conversion of our 3.0% convertible senior notes due 2014 at a conversion price of approximately $61.07 per share.

 

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To the extent that outstanding options outstanding as of December 31, 2011 have been or may be exercised 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.

 

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MATERIAL U.S. FEDERAL INCOME AND ESTATE TAX CONSEQUENCES TO NON-U.S. HOLDERS

The following summary describes the material U.S. federal income and estate tax consequences of the acquisition, ownership and disposition of our common stock acquired in this offering by a Non-U.S. Holder (as defined below). This discussion does not address all aspects of U.S. federal income and estate taxes and does not deal with foreign, state and local consequences that may be relevant to Non-U.S. Holders in light of their particular circumstances. Special rules may apply to certain Non-U.S. Holders that are subject to special treatment under the Internal Revenue Code of 1986, as amended, or the Code, such as financial institutions, insurance companies, tax-exempt organizations, broker-dealers and traders in securities, U.S. expatriates, “controlled foreign corporations,” “passive foreign investment companies,” corporations that accumulate earnings to avoid U.S. federal income tax, persons that hold our common stock as part of a “straddle,” “hedge,” “conversion transaction,” “synthetic security” or integrated investment, partnerships and other pass-through entities, and investors in such pass-through entities. Such Non-U.S. Holders are urged to consult their own tax advisors to determine the U.S. federal, state, local and other tax consequences that may be relevant to them. Furthermore, the discussion below is based upon the provisions of the Code, and Treasury regulations, rulings and judicial decisions thereunder as of the date hereof, and such authorities may be repealed, revoked or modified, perhaps retroactively, so as to result in U.S. federal income and estate tax consequences different from those discussed below. No ruling has been or will be sought from the Internal Revenue Service, or IRS, with respect to the matters discussed below, and there can be no assurance that the IRS will not take a contrary position regarding the tax consequences of the acquisition, ownership or disposition of our common stock, or that any such contrary position would not be sustained by a court. This discussion is limited to Non-U.S. Holders that purchase our common stock pursuant to this offering and hold our common stock as a capital asset within the meaning of Code Section 1221 (generally, property held for investment).

Persons considering the purchase of our common stock should consult their own tax advisors concerning the U.S. federal income and estate tax consequences in light of their particular situations as well as any consequences arising under the laws of any other taxing jurisdiction, including any state, local or foreign tax consequences, and those arising under any applicable tax treaty.

Except as otherwise described in the discussion of estate tax below, a “Non-U.S. Holder” is a beneficial owner of our common stock that is not a U.S. Holder or an entity treated as a partnership for U.S. tax purposes. A “U.S. Holder” means a beneficial owner of our common stock that is for U.S. federal income tax purposes (i) an individual who is a citizen or resident of the United States, (ii) a corporation or other entity treated as a corporation created or organized in or under the laws of the United States or any political subdivision thereof, (iii) an estate the income of which is subject to U.S. federal income taxation regardless of its source or (iv) a trust if it (x) is subject to the primary supervision of a court within the United States and one or more U.S. persons have the authority to control all substantial decisions of the trust or (y) has a valid election in effect under applicable U.S. Treasury regulations to be treated as a U.S. person.

If a partnership (including any entity or arrangement treated as a partnership for U.S. federal income tax purposes) acquires our common stock, the tax treatment of a partner in the partnership will generally depend upon the status of the partner and the activities of the partnership. Persons who are partners of partnerships holding our common stock are urged to consult their tax advisors.

Distributions

Subject to the discussion below, distributions, if any, made to a Non-U.S. Holder of our common stock out of our current or accumulated earnings and profits generally will constitute dividends for U.S. tax purposes and will be subject to withholding tax at a thirty percent rate or such lower rate as may be specified by an applicable income tax treaty. To obtain a reduced rate of withholding under a treaty, a Non-U.S. Holder generally will be required to provide us with a properly-executed IRS Form W-8BEN, or other appropriate form, certifying the Non-U.S. Holder’s entitlement to benefits under that treaty. Treasury regulations provide special rules to

 

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determine whether, for purposes of determining the applicability of a tax treaty, dividends paid to a Non-U.S. Holder that is an entity should be treated as paid to the entity or to those holding an interest in that entity. If a Non-U.S. Holder holds our common stock through a financial institution or other agent acting on the holder’s behalf, the holder will be required to provide appropriate documentation to such agent. The holder’s agent will then be required to provide certification to us or our paying agent, either directly or through other intermediaries.

We generally are not required to withhold tax on dividends paid to a Non-U.S. Holder that are effectively connected with the Non-U.S. Holder’s conduct of a trade or business within the United States if a properly-executed IRS Form W-8ECI, stating that the dividends are so connected (and are not exempt from U.S. federal income tax on net income under a treaty as described below), is filed with us. Effectively connected dividends will be subject to U.S. federal income tax on net income, generally in the same manner and at the regular rate as if the Non-U.S. Holder were a U.S. citizen or resident alien or a domestic corporation, as the case may be, unless a specific treaty exemption applies. If the Non-U.S. Holder is eligible for the benefits of a tax treaty between the United States and the holder’s country of residence, any effectively connected dividends would generally be subject to net U.S. federal income tax only if they are also attributable to a permanent establishment maintained by the holder in the United States. A corporate Non-U.S. Holder receiving effectively connected dividends may also be subject to an additional “branch profits tax”, which is imposed, under certain circumstances, at a rate of thirty percent (or such lower rate as may be specified by an applicable treaty) of the corporate Non-U.S. Holder’s effectively connected earnings and profits, subject to certain adjustments.

If you are eligible for a reduced rate of withholding tax pursuant to a tax treaty, you may generally obtain a refund of any excess amounts currently withheld if you timely file an appropriate claim for refund with the IRS.

To the extent distributions on our common stock, if any, exceed our current and accumulated earnings and profits, they will constitute a return of capital and will first reduce your basis in our common stock, but not below zero, and then will be treated as gain from the sale of stock.

Gain on disposition of common stock

Subject to the discussion below regarding backup withholding and legislation relating to foreign accounts, a Non-U.S. Holder generally will not be subject to U.S. federal income tax with respect to gain realized on a sale or other disposition of our common stock unless (i) the gain is effectively connected with a trade or business of such holder in the United States and, if required by an applicable income tax treaty, attributable to a permanent establishment maintained in the United States by the Non-U.S. Holder, (ii) the Non-U.S. Holder is a nonresident alien individual and is present in the United States for 183 or more days in the taxable year of the disposition and certain other conditions are met, or (iii) we are or have been a “United States real property holding corporation” within the meaning of Code Section 897(c)(2) at any time within the shorter of the five-year period preceding such disposition or such holder’s holding period. In general, we would be a United States real property holding corporation if interests in U.S. real estate comprised at least half of our business assets. We believe that we are not, and do not anticipate becoming, a United States real property holding corporation. Even if we are treated as a United States real property holding corporation, gain realized by a Non-U.S. Holder on a disposition of our common stock will not be subject to U.S. federal income tax so long as (1) the Non-U.S. Holder owned directly, indirectly and constructively, no more than five percent of our common stock at all times within the shorter of (a) the five year period preceding the disposition or (b) the holder’s holding period and (2) our common stock is regularly traded on an established securities market. There can be no assurance that our common stock will continue to qualify as regularly traded on an established securities market.

If you are a Non-U.S. Holder described in (i) above, you will be required to pay tax on the net gain derived from the sale at generally applicable United States federal income tax rates, subject to an applicable income tax treaty providing otherwise, and corporate Non-U.S. Holders described in (i) above may be subject to the branch profits tax at a thirty percent rate or such lower rate as may be specified by an applicable income tax treaty. If you are an individual Non-U.S. Holder described in (ii) above, you will be required to pay a flat thirty percent tax

 

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(or a reduced rate under an applicable income tax treaty) on the gain derived from the sale, which gain may be offset by U.S. source capital losses if you have timely filed tax returns with respect to such losses (even though you are not considered a resident of the United States). If you are a Non-U.S. Holder described in (iii) above and an exception from U.S. federal income tax does not apply (e.g., because our common stock does not qualify as regularly traded on an established securities market or, if it does so qualify, you own more than five percent of our common stock during the relevant period), any gain derived from the sale would be treated as effectively connected with a trade or business in the United States, generally taxable in the manner described in (i) above, and a withholding tax could apply.

Information reporting and backup withholding

Generally, we must report to the IRS the amount of dividends paid, the name and address of the recipient, and the amount, if any, of tax withheld. A similar report is sent to the holder. Pursuant to tax treaties or certain other agreements, the IRS may make its reports available to tax authorities in the recipient’s country of residence. Backup withholding will generally not apply to payments of dividends made by us or our paying agents to a Non-U.S. Holder if the holder has provided its federal taxpayer identification number, if any, or the required certification that it is not a U.S. person (which is generally provided by furnishing a properly-executed IRS Form W-8BEN or IRS Form W-8ECI), unless the payer otherwise has knowledge or reason to know that the payee is a U.S. person, or the Non-U.S. Holder otherwise establishes an exemption. The backup withholding rate is currently twenty-eight percent.

Under current U.S. federal income tax law, information reporting and backup withholding will apply to the proceeds of a disposition of our common stock effected by or through a U.S. office of a broker unless the disposing holder certifies as to its non-U.S. status or otherwise establishes an exemption. Generally, U.S. information reporting and backup withholding will not apply to a payment of disposition proceeds where the transaction is effected outside the United States through a non-U.S. office of a non-U.S. broker. However, information reporting and backup withholding will apply to a payment of disposition proceeds if the broker has actual knowledge or reason to know that the holder is a U.S. person.

Backup withholding is not an additional tax. Rather, the tax liability of persons subject to backup withholding will be reduced by the amount of tax withheld. If withholding results in an overpayment of taxes, a refund may be obtained, provided that the required information is timely furnished to the IRS.

Legislation relating to foreign accounts

Legislation enacted in 2010 may impose withholding taxes on certain types of payments made to “foreign financial institutions” (as specifically defined in this legislation) and certain other non-U.S. entities (including financial intermediaries). Under this legislation, the failure to comply with additional certification, information reporting and other specified requirements could result in withholding tax being imposed on payments of dividends and sales proceeds to foreign intermediaries and certain Non-U.S. Holders. The legislation imposes a thirty percent withholding tax on dividends, or gross proceeds from the sale or other disposition of, common stock paid to a foreign financial institution (as specially defined for this purpose) or to a foreign non-financial entity, unless (i) the foreign financial institution undertakes certain diligence and reporting obligations or (ii) the foreign non-financial entity either certifies it does not have any substantial United States owners or furnishes identifying information regarding each substantial United States owner. If the payee is a foreign financial institution, it must enter into an agreement with the United States Treasury requiring, among other things, that it undertake to identify accounts held by certain United States persons or United States-owned foreign entities, annually report certain information about such accounts, and withhold thirty percent on payments to account holders whose actions prevent it from complying with these reporting and other requirements. Under certain transition rules, any obligation under this legislation to withhold with respect to dividends on our common stock will not begin until January 1, 2014 and with respect to gross proceeds of a sale or other disposition of our

 

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common stock will not begin until January 1, 2015. Prospective investors should consult their tax advisors regarding this legislation.

Federal estate tax

An individual who at the time of death is not a citizen or resident of the United States and who is treated as the owner of, or has made certain lifetime transfers of, an interest in our common stock will be required to include the value thereof in his or her taxable estate for U.S. federal estate tax purposes, and may be subject to U.S. federal estate tax unless an applicable estate tax treaty provides otherwise. The test for whether an individual is a resident of the United States for federal estate tax purposes differs from the test used for U.S. federal income tax purposes. Some individuals, therefore, may be “Non-U.S. Holders” for U.S. federal income tax purposes, but not for U.S. federal estate tax purposes, and vice versa.

THE PRECEDING DISCUSSION OF U.S. FEDERAL INCOME AND ESTATE TAX CONSIDERATIONS IS FOR GENERAL INFORMATION ONLY. IT IS NOT TAX ADVICE. EACH PROSPECTIVE INVESTOR SHOULD CONSULT ITS OWN TAX ADVISOR REGARDING THE TAX CONSEQUENCES OF PURCHASING, HOLDING AND DISPOSING OF OUR COMMON STOCK, INCLUDING THE CONSEQUENCES OF ANY PROPOSED CHANGE IN APPLICABLE LAW.

 

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UNDERWRITING

Under the terms and subject to the conditions contained in an underwriting agreement dated March         , 2012, we have agreed to sell to Credit Suisse Securities (USA) LLC all of the shares of common stock.

The underwriting agreement provides that the underwriter is obligated to purchase all the shares of common stock in the offering if any are purchased, other than those shares covered by the underwriter’s option described below. Subject to the terms and conditions of the underwriting agreement, the underwriter has agreed to purchase shares at a price of $         per share.

We have granted to the underwriter a 30-day option to purchase up to              additional shares at a price of $         per share.

The underwriter may offer the shares of common stock in transactions on The NASDAQ Global Select Market, in the over-the-counter market or through negotiated transactions at market prices or at negotiated prices. The underwriter may effect such transactions by selling the shares to or through dealers and such dealers may receive compensation in the form of discounts, concessions or commissions from the underwriter and/or purchasers of the shares for whom they may act as agents or to whom they may sell as principal. The difference between the price at which the underwriter purchases the shares and the price at which the underwriter resells such shares, which may include a commission equivalent of up to $         per share, may be deemed underwriting compensation.

We estimate that our out of pocket expenses for this offering will be approximately $            , or $             with the underwriter’s option.

We have agreed that we will not offer, sell, contract to sell, pledge or otherwise dispose of, directly or indirectly, or file with the Securities and Exchange Commission a registration statement under the Securities Act relating to, any shares of our common stock or securities convertible into or exchangeable or exercisable for any shares of our common stock, or publicly disclose the intention to make any offer, sale, pledge, disposition or filing, without the prior written consent of Credit Suisse Securities (USA) LLC for a period of 60 days after the date of this prospectus , except (i) issuances pursuant to the conversion or exchange of convertible or exchangeable securities or the exercise of warrants or options, in each case outstanding on the date hereof and disclosed to the underwriter or issuable under clause (ii) below, (ii) grants of stock options and other securities pursuant to the terms of a plan in effect on the date hereof and disclosed to the underwriter and (iii) issuances to one or more counterparties in connection with the consummation of a strategic partnership, joint venture, collaboration, merger or the acquisition or license of any business products or technology, provided that, with respect to this clause (iii), (a) the sum of the aggregate number of shares of our common stock or securities convertible into or exchangeable or exercisable for any shares of our common stock so issued will not exceed 5% of the total outstanding shares of common stock immediately following the completion of this offering and (b) prior to the issuance of such common stock or securities that are locked up, each recipient of such locked up common stock or securities agrees in writing not to sell, offer, dispose of or otherwise transfer any such locked up common stock or securities during the lock-up period.

Our directors and executive officers have agreed that they will not offer, sell, contract to sell, pledge or otherwise dispose of, directly or indirectly, any shares of our common stock or securities convertible into or exchangeable or exercisable for any shares of our common stock, enter into a transaction that would have the same effect, or enter into any swap, hedge or other arrangement that transfers, in whole or in part, any of the economic consequences of ownership of our common stock, whether any of these transactions are to be settled by delivery of our common stock or other securities, in cash or otherwise, or publicly disclose the intention to make any offer, sale, pledge or disposition, or to enter into any transaction, swap, hedge or other arrangement, without, in each case, the prior written consent of Credit Suisse Securities (USA) LLC for a period of 60 days after the date of this prospectus supplement. The above restrictions will not apply to transactions relating to

 

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(a) any shares of our common stock acquired by the director or officer in the open market; (b) a transfer of our securities as a bona fide gift, provided the transferee agrees in writing to be bound by the terms of the lock-up agreement prior to such transfer, and provided further that it shall be a condition to such transfer that no filing or other announcement by any party under the Exchange Act or otherwise shall be required or shall be voluntarily made in connection with such transfer (other than a filing made after the expiration of the lock-up period); (c) a transfer of our securities to the immediate family of the director or officer or any trust or partnership for the direct or indirect benefit of the director or officer and/or the immediate family of the director or officer, provided the transferee agrees in writing to be bound by the terms of the lock-up agreement prior to such transfer, and provided further that it shall be a condition to such transfer that no filing or other announcement by any party under the Exchange Act or otherwise shall be required or shall be voluntarily made in connection with such transfer (other than a filing made after the expiration of the lock-up period); (d) dispositions by will or intestate succession or to any trust or partnership for the direct or indirect benefit of the director or officer and/or the immediate family of the director or officer, provided that such donee or transferee agrees in writing to be bound by the terms of the lock-up agreement prior to such disposition, and provided further that it shall be a condition to such transfer that no filing or other announcement by any party under the Exchange Act or otherwise shall be required or shall be voluntarily made in connection with such transfer (other than a filing made after the expiration of the lock-up period); (e) a transfer of our securities to the Company in satisfaction of any tax withholding obligation, provided that the company shall provide not less than 2 business days prior written notice to the underwriter of such transfer; (f) a transfer of securities to the Company pursuant to the “net” or “cashless” exercise of outstanding options to purchase our common stock in accordance with their terms, including via swap, provided that any such common stock acquired upon the net or cashless exercise shall be subject to the restrictions imposed by the lock-up agreement, and provided that the company shall provide not less than 2 business days prior written notice to the underwriter of such transfer; or (g) dispositions pursuant to trading plans meeting the requirements of Rule 10b5-1 under the Exchange Act that are in effect as of the date of the lock-up agreement and have been previously disclosed to the underwriter.

We have agreed to indemnify the underwriter against liabilities under the Securities Act, or contribute to payments that the underwriter ay be required to make in that respect.

The shares of common stock have been approved for listing on The NASDAQ Global Select Market, under the symbol “AMLN”.

In connection with the offering the underwriter may engage in stabilizing transactions, over-allotment transactions, syndicate covering transactions, penalty bids, and passive market making in accordance with Regulation M under the Exchange Act.

 

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Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum.

 

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Over-allotment involves sales by the underwriter of shares in excess of the number of shares the underwriter is obligated to purchase, which creates a syndicate short position. The short position may be either a covered short position or a naked short position. In a covered short position, the number of shares over-allotted by the underwriter is not greater than the number of shares that it may purchase in the underwriter’s option. In a naked short position, the number of shares involved is greater than the number of shares in the underwriter’s option. The underwriter may close out any covered short position by either exercising its option and/or purchasing shares in the open market.

 

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Syndicate covering transactions involve purchases of the common stock in the open market after the distribution has been completed in order to cover syndicate short positions. In determining the source of shares to close out the short position, the underwriter will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which it may purchase shares through the underwriter’s option. If the underwriter sells more shares than could be covered by

 

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the underwriter’s option, a naked short position, the position can only be closed out by buying shares in the open market. A naked short position is more likely to be created if the underwriter is concerned that there could be downward pressure on the price of the shares in the open market after pricing that could adversely affect investors who purchase in the offering.

 

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Penalty bids permit the underwriter to reclaim a selling concession from a syndicate member when the common stock originally sold by the syndicate member is purchased in a stabilizing or syndicate covering transaction to cover syndicate short positions.

 

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In passive market making, the market makers in the common stock who is the underwriter or prospective underwriters may, subject to limitations, make bids for or purchases of our common stock until the time, if any, at which a stabilizing bid is made.

These stabilizing transactions, syndicate covering transactions and penalty bids may have the effect of raising or maintaining the market price of our common stock or preventing or retarding a decline in the market price of the common stock. As a result the price of our common stock may be higher than the price that might otherwise exist in the open market. These transactions may be effected on The NASDAQ Global Select Market or otherwise and, if commenced, may be discontinued at any time.

A prospectus in electronic format may be made available on the web sites maintained by the underwriter, or selling group members, if any, participating in this offering and the underwriter may distribute prospectuses electronically.

The underwriter has performed investment banking, commercial banking, dealer and advisory services for us or our affiliates from time to time, for which it has received customary fees and expenses. The underwriter may, from time to time, engage in transactions with and perform services for us or our affiliates in the ordinary course of its respective businesses. Among other things, the underwriter provided the Company with a fairness opinion for purposes of the Company and Eli Lilly’s settlement and termination agreement.

 

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NOTICE TO CANADIAN RESIDENTS

Resale Restrictions

The distribution of the shares in Canada is being made only in the provinces of Ontario, Quebec, Alberta, British Columbia and Manitoba on a private placement basis exempt from the requirement that we prepare and file a prospectus with the securities regulatory authorities in each province where trades of shares are made. Any resale of the shares in Canada must be made under applicable securities laws which may vary depending on the relevant jurisdiction, and which may require resales to be made under available statutory exemptions or under a discretionary exemption granted by the applicable Canadian securities regulatory authority. Purchasers are advised to seek legal advice prior to any resale of the shares.

Representations of Purchasers

By purchasing shares in Canada and accepting delivery of a purchase confirmation, a purchaser is representing to us and the dealer from whom the purchase confirmation is received that:

 

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the purchaser is entitled under applicable provincial securities laws to purchase the shares without the benefit of a prospectus qualified under those securities laws as it is an “accredited investor” as defined under National Instrument 45-106 – Prospectus and Registration Exemptions,

 

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the purchaser is a “Canadian permitted client” as defined in National Instrument 31-103 - Registration Requirements and Exemptions , or as otherwise interpreted and applied by the Canadian Securities Administrators,

 

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where required by law, the purchaser is purchasing as principal and not as agent,

 

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the purchaser has reviewed the text above under “Resale Restrictions”, and

 

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the purchaser acknowledges and consents to the provision of specified information concerning the purchase of the shares to the regulatory authority that by law is entitled to collect the information, including certain personal information. For purchasers in Ontario, questions about such indirect collection of personal information should be directed to Administrative Support Clerk, Ontario Securities Commission, Suite 1903, Box 55, 20 Queen Street West, Toronto, Ontario M5H 3S8 or to (416) 593-3684.

Rights of Action—Ontario Purchasers

Under Ontario securities legislation, certain purchasers who purchase a security offered by this document during the period of distribution will have a statutory right of action for damages, or while still the owner of the shares, for rescission against us in the event that this document contains a misrepresentation without regard to whether the purchaser relied on the misrepresentation. The right of action for damages is exercisable not later than the earlier of 180 days from the date the purchaser first had knowledge of the facts giving rise to the cause of action and three years from the date on which payment is made for the shares. The right of action for rescission is exercisable not later than 180 days from the date on which payment is made for the shares. If a purchaser elects to exercise the right of action for rescission, the purchaser will have no right of action for damages against us. In no case will the amount recoverable in any action exceed the price at which the shares were offered to the purchaser and if the purchaser is shown to have purchased the securities with knowledge of the misrepresentation, we will have no liability. In the case of an action for damages, we will not be liable for all or any portion of the damages that are proven to not represent the depreciation in value of the shares as a result of the misrepresentation relied upon. These rights are in addition to, and without derogation from, any other rights

 

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or remedies available at law to an Ontario purchaser. The foregoing is a summary of the rights available to an Ontario purchaser. Ontario purchasers should refer to the complete text of the relevant statutory provisions.

Enforcement of Legal Rights

All of our directors and officers as well as the experts named herein may be located outside of Canada and, as a result, it may not be possible for Canadian purchasers to effect service of process within Canada upon us or those persons. All or a substantial portion of our assets and the assets of those persons may be located outside of Canada and, as a result, it may not be possible to satisfy a judgment against us or those persons in Canada or to enforce a judgment obtained in Canadian courts against us or those persons outside of Canada.

Taxation and Eligibility for Investment

Canadian purchasers of shares should consult their own legal and tax advisors with respect to the tax consequences of an investment in the shares in their particular circumstances and about the eligibility of the investment by the purchaser under relevant Canadian legislation.

LEGAL MATTERS

The validity of the common stock offered by this prospectus supplement and the accompanying prospectus will be passed upon for us by Cooley LLP, San Diego, California. Davis Polk & Wardwell LLP, Menlo Park, California, is counsel for the underwriter in connection with this offering.

EXPERTS

Ernst & Young LLP, independent registered public accounting firm, has audited our consolidated financial statements and schedule included in our Annual Report on Form 10-K for the year ended December 31, 2011, and the effectiveness of our internal control over financial reporting as of December 31, 2011, as set forth in their reports, which are incorporated by reference into this prospectus supplement and elsewhere in the registration statement. Our financial statements and schedule are incorporated by reference in reliance on Ernst & Young LLP’s reports, given on their authority as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION

This prospectus supplement and the accompanying prospectus are part of the registration statement on Form S-3 we filed with the SEC under the Securities Act and do not contain all the information set forth in the registration statement. Whenever a reference is made in this prospectus supplement or the accompanying prospectus to any of our contracts, agreements or other documents, the reference may not be complete and you should refer to the exhibits that are a part of the registration statement or the exhibits to the reports or other documents incorporated by reference in this prospectus supplement and the accompanying prospectus for a copy of such contract, agreement or other document. Because we are subject to the information and reporting requirements of the Exchange Act, we file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at http://www.sec.gov. You may also read and copy any document we file 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.

 

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INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to “incorporate by reference” information from other documents that we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus supplement and the accompanying prospectus. Information contained in this prospectus supplement and the accompanying prospectus and information that we file with the SEC in the future and incorporate by reference in this prospectus supplement and the accompanying prospectus will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings (other than Current Reports on Form 8-K furnished under Item 2.02 or Item 7.01 and exhibits filed on such form that are related to such items) we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of the prospectus supplement and before the sale of all the securities covered by this prospectus supplement:

 

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our Annual Report on Form 10-K for our fiscal year ended December 31, 2011, filed with the SEC on February 22, 2012;

 

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our Definitive Proxy Statement on Schedule 14A filed with the SEC on April 13, 2011;

 

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our Current Reports on Form 8-K filed with the SEC on January 30, 2012, February 9, 2012 and March 6, 2012;

 

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the description of our common stock set forth in our registration statement on Form 8-A, which was filed with the SEC on November 27, 1991, including any amendment or reports filed for the purpose of updating this information; and

 

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the description of the rights to purchase series A junior participating preferred stock set forth in our current report on Form 8-K, which was filed on June 18, 2002, as amended as set forth in Exhibit 4.5 to our Annual Report on Form 10-K for the fiscal year ended December 31, 2002, which was filed on March 31, 2003.

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

Amylin Pharmaceuticals, Inc.

9360 Towne Centre Drive

San Diego, California 92121

(858) 552-2200 ext. 7299

Attention: Investor Relations

In accordance with Rule 412 of the Securities Act, any statement contained in a document incorporated by reference herein shall be deemed modified or superseded to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes such statement.

 

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PROSPECTUS		March 7, 2012

 

COMMON STOCK

 

 

We may, from time to time, offer to sell common stock in amounts, at prices and on terms described in one or more supplements to this prospectus.

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 or in a supplement to this prospectus or may be set forth in one or more documents incorporated by reference in this prospectus.

Our securities may be offered and sold in the same offering or in separate offerings; to or through underwriters, dealers, and agents; or directly to purchasers. The names of any underwriter, dealer or agents involved in the sale of our securities and their compensation will be described in an applicable prospectus supplement. See “Plan of Distribution.”

Our common stock trades on the NASDAQ Global Select Market under the symbol “AMLN.”

 

 

Investing in our securities involves significant risks. See “ Risk Factors ” on Page 2 of this prospectus and in the applicable prospectus supplement before investing in any securities.

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

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TABLE OF CONTENTS

 

About This Prospectus			i
Prospectus Summary			1
Risk Factors			2
Forward Looking Statements			2
Use Of Proceeds			2
Description Of Capital Stock			3
Plan of Distribution			6
Legal Matters			7
Experts			7
Where You Can Find More Information			7
Incorporation by Reference			8

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or the SEC, using the “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. By using a shelf registration statement, we may offer and 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 of common stock we may sell pursuant to the registration statement.

Neither we nor the underwriters have authorized anyone to provide you with information different from that contained in or incorporated by reference into this prospectus or any applicable prospectus supplement. We take no responsibility for, and can provide no assurance as to the reliability of, any information that others may give you. This document may only be used where it is legal to sell these securities. You should not assume that the information contained in this prospectus, or in any prospectus supplement, is accurate as of any date other than its date regardless of the time of delivery of the prospectus or prospectus supplement or any sale of the common stock. Our business, financial condition, results of operations and prospects may have changed since that date.

This prospectus and the information incorporated herein by reference includes trademarks, service marks and trade names owned by us or other companies. All trademarks, service marks and trade names included or incorporated by reference in this prospectus are the property of their respective owners.

We urge you to read carefully both this prospectus and any prospectus supplement accompanying this prospectus, together with the information incorporated herein by reference as described under the heading “Where You Can Find More Information,” before deciding whether to invest in any of the securities being offered.

 

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RISK FACTORS

Investing in our securities involves risks. Please see the risk factors described under the caption “Risk Factors” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2011, which is on file with the SEC and is incorporated by reference in this prospectus and in any accompanying prospectus supplement. Before making an investment decision, you should carefully consider these risks as well as information we include or incorporate by reference in this prospectus and in any accompanying prospectus supplement. The risks and uncertainties we have described are not the only ones that we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our business or operations.

FORWARD-LOOKING STATEMENTS

This prospectus, each prospectus supplement and the information incorporated by reference in this prospectus and each prospectus supplement contain certain statements that constitute “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. The words “anticipate,” “expect,” “believe,” “goal,” “plan,” “intend,” “estimate,” “may,” “will” and similar expressions and variations thereof are intended to identify forward-looking statements, but are not the exclusive means of identifying such statements. Those statements appear in this prospectus, any accompanying prospectus supplement and the documents incorporated herein and therein by reference, particularly in the sections entitled “Prospectus Summary,” “Risk Factors,” “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and “Business,” and include statements regarding the intent, belief or current expectations of Amylin and management that are subject to known and unknown risks, uncertainties and assumptions. Actual results may differ materially from those projected in the forward-looking statements as a result of various factors.

Because forward-looking statements are inherently subject to risks and uncertainties, some of which cannot be predicted or quantified, you should not rely upon forward-looking statements as predictions of future events. The events and circumstances reflected in the forward-looking statements may not be achieved or occur and actual results could differ materially from those projected in the forward-looking statements. Except as required by applicable law, including the securities laws of the United States and the rules and regulations of the SEC, we do not plan to publicly update or revise any forward-looking statements contained herein after we distribute this prospectus, whether as a result of any new information, future events or otherwise.

USE OF PROCEEDS

Unless otherwise indicated in an applicable prospectus supplement, we will use the net proceeds from the sale of the securities for general corporate purposes and to fund our capital expenditures and working capital requirements. We may also use some of the net proceeds for acquisitions of complementary businesses and technologies, although no such acquisitions are currently contemplated or pending.

 

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DESCRIPTION OF CAPITAL STOCK

Our authorized capital stock consists of 450,000,000 shares of common stock, $0.001 par value, and 7,500,000 shares of preferred stock, $0.001 par value, of which 2,000,000 shares have been designated as series A junior participating preferred stock. As of March 1, 2012, there were 147,809,575 shares of common stock outstanding and no shares of preferred stock outstanding.

Common Stock

The holders of common stock are entitled to one vote for each share held of record on all matters submitted to a vote of the stockholders and do not have cumulative voting rights. Accordingly, holders of a majority of the shares of common stock entitled to vote in any election of directors may elect all of the directors standing for election. Subject to preferences that may be applicable to any outstanding shares of preferred stock, the holders of common stock are entitled to receive ratably such dividends as may be declared by the board of directors out of funds legally available for distribution. Upon our liquidation, dissolution or winding up, holders of our common stock are entitled to share ratably in all assets remaining after payment of liabilities and the liquidation preferences of any outstanding shares of preferred stock. Holders of common stock have no preemptive rights and no right to convert their common stock into any other securities. There are no redemption or sinking fund provisions applicable to our common stock. All outstanding shares of common stock are, and all shares of common stock that may be issued upon conversion of the notes will be, fully paid and non-assessable.

Preferred Stock

Pursuant to our amended and restated certificate of incorporation, our board of directors has the authority, without further action by the stockholders, to issue up to 7,500,000 shares of preferred stock in one or more series. Our board shall determine the rights, preferences, privileges and restrictions of the preferred stock, including dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting any series or the designation of any series. Our board has designated 2,000,000 shares of preferred stock as series A junior participating preferred stock.

The issuance of preferred stock could adversely affect the voting power of holders of common stock, and the likelihood that holders of preferred stock will receive dividend payments and payments upon liquidation may have the effect of delaying, deferring or preventing a change in control of our company, which could depress the trading price of the notes and our common stock being offered by this prospectus.

Anti-Takeover Effects of Provisions of Delaware Law and Our Charter Documents

Delaware Takeover Statute.  We are subject to the provisions of Section 203 of the Delaware General Corporation Law. In general, the statute 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 the business combination is approved in a prescribed manner. For purposes of Section 203, a business combination includes a merger, asset sale or other transaction resulting in a financial benefit to the interested stockholder, and an interested stockholder is a person who, together with affiliates and associates, owns (or within three years prior, did own) 15% or more of the corporation’s voting stock.

Charter Documents.  Our amended and restated certificate of incorporation requires that any action required or permitted to be taken by our stockholders must be effected at a duly called annual or special meeting of stockholders and may not be effected by a consent in writing. Additionally, our amended and restated certificate of incorporation:

 

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generally prohibits the use of cumulative voting in the election of directors;

 

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provides that the authorized number of directors may be changed only by resolution of our board of directors; and

 

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authorizes our board of directors to issue blank check preferred stock, which, if convertible into common stock, could increase the number of shares of common stock outstanding.

Our amended and restated bylaws provide that candidates for director may be nominated only by our board of directors or by a stockholder, who must give us 120 days advance notice of a proposed nominee. Also, stockholders must give us 120 days advance notice of business to be brought by a stockholder before a stockholder’s meeting. The authorized number of directors is fixed in accordance with our amended and restated certificate of incorporation. Our board of directors may appoint new directors to fill vacancies or newly created directorships. Our amended and restated bylaws also limit who may call a special meeting of stockholders.

Our amended and restated certificate of incorporation contains a provision that requires the approval of the holders of 66  ² / 3 % of our voting stock as a condition to a merger or various other business transactions with or proposed by an interested stockholder, which, for these purposes, means a holder of 15% or more of our voting stock. This approval is not required if the transaction is approved by our continuing directors, which, for these purposes, includes those of our directors who were either originally elected upon our incorporation, are not interested stockholders, or affiliated with an interested stockholder, or were nominated by, or whose election to the board of directors was recommended or approved by, a majority of the foregoing directors. This approval is also not required if certain minimum price criteria and other procedural requirements are met. The minimum price criteria generally require that, in a transaction in which stockholders are to receive payments, holders of our common stock must receive a value equal to the highest price paid by any interested stockholder for shares of our common stock during the prior two years and that such payment be made in cash or in the type of consideration paid by the interested stockholder for the greatest portion of its shares. Our board of directors believes that this provision will help assure that all of our stockholders will be treated similarly if certain kinds of business combinations are effected. However, this provision may make it more difficult to accomplish certain transactions that are opposed by the incumbent board of directors and that could be beneficial to stockholders.

Delaware law and these charter provisions may have the effect of deterring hostile takeovers or delaying changes in control of our management, which could depress the trading price of the notes and our common stock.

Stockholder Rights Plan

We have 2,000,000 shares of series A junior participating preferred stock authorized and reserved for issuance in connection with our stockholder rights plan set forth in our Rights Agreement dated June 17, 2002 with American Stock Transfer and Trust Company, as rights agent. A copy of our Rights Agreement has been incorporated by reference as an exhibit to the registration statement, of which this prospectus is a part. Each outstanding share of our common stock has one preferred stock purchase right. The rights expire on June 16, 2012 unless exchanged or redeemed prior to that date. Our board may extend the expiration date.

Generally, if any person or group acquires 15% or more of our common stock, the rights holders will be entitled to receive upon exercise of a preferred stock purchase right, the number of shares of common stock that, at that time, have a market value equal to twice the purchase price of the right. The shares of preferred stock acquired upon exercise of a purchase right are not redeemable and are entitled to preferential quarterly dividends. They are also entitled to preferential rights in the event of liquidation. Finally, if any business combination occurs in which our common shares are exchanged for shares of another company, each preferred share will be entitled to receive 100 times the amount received per common share of the company.

If we are acquired in a business combination, the purchase rights holders will be entitled to acquire, for the purchase price, the number of shares of common stock of the acquiring corporation that, at the time, have a market value equal to twice the purchase price of the right. Our board has the right to redeem the purchase rights in certain circumstances for $0.001 per share, subject to adjustment. The rights plan is designed to protect our

 

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stockholders in the event of unsolicited offers to acquire us and other coercive takeover tactics, which, in the board’s opinion, would impair its ability to represent our stockholders’ interests. The rights plan may make an unsolicited takeover more difficult or less likely to occur or may prevent a takeover, even though a takeover may offer our stockholders the opportunity to sell their stock at a price above the prevailing market rate and may be favored by a majority of our stockholders.

Listing

Our common stock is listed on the NASDAQ Global Select Market under the symbol “AMLN.”

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is American Stock Transfer and Trust. Its address is 59 Maiden Lane, Plaza Level, New York, New York 10038 and its telephone number is (718) 921-8124.

 

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PLAN OF DISTRIBUTION

We may sell the offered securities in one or more of the following ways:

 

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through an underwriter or underwriters;

 

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through dealers;

 

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through agents;

 

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directly to one or more purchasers, including affiliates of ours; or

 

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through a combination of any of these methods of sale.

The applicable prospectus supplement will contain the terms of the offerings of any securities. The public offering price and any discount or concessions allowed or reallowed to dealers may be changed from time to time. The applicable prospectus supplement will contain the expected time of delivery of the securities for which this prospectus is delivered.

Unless otherwise indicated in the applicable prospectus supplement, if underwriters are used in the sale of the securities, the underwriting agreement will provide that the obligations of the underwriters are subject to certain conditions precedent and that the underwriters will be obligated to purchase all of the securities if any are purchased. In connection with the sale of securities, underwriters may receive compensation from us or purchasers of securities for whom they may act as agents in the form of discounts, concessions or commissions. Underwriters may sell securities to or through dealers, and dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/or commissions from the purchasers for whom they may act as agent.

Underwriters, agents or dealers participating in the distribution of securities may be deemed to be underwriters, and any discounts and commissions received by them and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions under the Securities Act. The securities may be sold in one or more transactions either at a fixed price or at prices which may be changed based on market prices prevailing at the time of sale, at prices related to the prevailing market prices or at negotiated prices.

We may indemnify the underwriters, agents or dealers who participate in the distribution of securities against certain liabilities, including liabilities under the Securities Act. We may also contribute to payments that the underwriters, dealers or agents or any of their controlling persons may be required to make in respect of such liabilities. Underwriters, agents or dealers may be customers of, engage in transactions with or perform services for us or our subsidiaries in the ordinary course of business.

If so indicated in a prospectus supplement, we will authorize underwriters, dealers and agents to solicit offers by certain institutions to purchase securities from us pursuant to delayed delivery contracts providing for payment and delivery on the date stated in the prospectus supplement. These contracts will be subject only to those conditions contained in the prospectus supplement. The prospectus supplement will also contain the commission payable for solicitation of any of these contracts.

Offers to purchase securities may be solicited directly by us and sales of securities may be made by us directly to institutional investors or others who may be deemed to be underwriters within the meaning of the Securities Act, with respect to any resale of the securities. The terms of any such sales will be described in the prospectus supplement relating to the securities. Except as contained in the applicable prospectus supplement, no director, officer or employee of ours will solicit or receive a commission in connection with the direct sales by us of the securities, although these persons may respond to inquiries by potential purchasers and perform ministerial and clerical work in connection with any such direct sales.

 

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LEGAL MATTERS

The validity of the common stock issued under this prospectus will be passed upon by Cooley LLP, San Diego, California.

EXPERTS

Ernst & Young LLP, independent registered public accounting firm, has audited our consolidated financial statements and schedule included in our Annual Report on Form 10-K for the year ended December 31, 2011, and the effectiveness of our internal control over financial reporting as of December 31, 2011, as set forth in their reports, which are incorporated by reference into this prospectus and elsewhere in the registration statement. Our financial statements and schedule are incorporated by reference in reliance on Ernst & Young LLP’s reports, given on their authority as experts in accounting and auditing.

WHERE YOU CAN FIND ADDITIONAL INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s web site at www.sec.gov . You may also read and copy any document we file at the SEC’s public reference room at 100 F Street, N.E., Washington, D.C. 20549. You may obtain information on the operation of the SEC’s public reference room in Washington, D.C. by calling the SEC at 1-800-SEC-0330.

We have filed with the SEC a registration statement under the Securities Act relating to the offering of these securities. The registration statement, including the attached exhibits, contains additional relevant information about us and the securities. This prospectus does not contain all of the information set forth in the registration statement. You can obtain a copy of the registration statement, at prescribed rates, from the SEC at the address listed above. The registration statement and the documents referred to below under “Incorporation by Reference” are also available on our corporate website, www.amylin.com . We have not incorporated by reference into this prospectus the information on our website, and you should not consider it to be a part of this prospectus.

 

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INCORPORATION BY REFERENCE

The SEC allows us to “incorporate by reference” in this prospectus the information that we file with it. This means that we can disclose important information to you in this document by referring you to other filings we have made with the SEC. The information incorporated by reference is considered to be part of this prospectus. The information incorporated by reference in this prospectus is accurate only as of the date of the information on the front cover of the applicable document, or such earlier date as is expressly stated or otherwise apparent with respect to such incorporated information in the applicable document, regardless of the time of delivery of this prospectus or any sale of securities.

This prospectus incorporates by reference the documents listed below, which we have filed with the SEC:

 

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our Annual Report on Form 10-K for our fiscal year ended December 31, 2011, filed on February 22, 2012;

 

•

our Definitive Proxy Statement on Schedule 14A filed on April 13, 2011;

 

•

our Current Reports on Form 8-K filed on January 30, 2012, February 9, 2012 and March 6, 2012;

 

•

the description of our common stock set forth in our registration statement on Form 8-A, which was filed on November 27, 1991, including any amendment or reports filed for the purpose of updating this information; and

 

•

the description of the rights to purchase series A junior participating preferred stock set forth in our Current Report on Form 8-K, which was filed on June 18, 2002, as amended as set forth in Exhibit 4.5 to our Annual Report on Form 10-K for the fiscal year ended December 31, 2002, which was filed on March 31, 2003.

We incorporate by reference any additional documents that we may file with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act (other than the portions of those made pursuant to Item 2.02 or Item 7.01 of Form 8-K or other information “furnished” to the SEC) between the date that we initially filed the registration statement to which this prospectus relates and the termination of the offering of the securities. These documents may include periodic reports, like Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as well as Proxy Statements. Any material that we subsequently file with the SEC will automatically update and replace the information previously filed with the SEC.

This prospectus may contain information that updates, modifies or is contrary to information in one or more of the documents incorporated by reference in this prospectus. You should rely only on the information incorporated by reference or provided in this prospectus. We have not authorized anyone else to provide you with different information. You should not assume that the information in this prospectus is accurate as of any date other than the date of this prospectus or the date of the documents incorporated by reference in this prospectus.

We will provide to each person, including any beneficial owner, to whom this prospectus is delivered, upon written or oral request, at no cost, a copy of any and all of the information that is incorporated by reference in this prospectus.

Requests for such documents should be directed to:

Amylin Pharmaceuticals, Inc.

9360 Towne Centre Drive

San Diego, California 92121

(858) 552-2200 ext. 7299

Attention: Investor Relations

In addition, copies of our filings are available through our corporate website at www.amylin.com as soon as reasonably practicable after we electronically file such material with, or furnish it, to the SEC.

 

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