UNDERWRITING AGREEMENT

“ Closing Date ” has the meaning defined in Section 3 hereof.

“ Commission ” means the Securities and Exchange Commission.

“ Effective Time ” of the Registration Statement relating to the Offered Securities means the time of the first contract of sale for the Offered Securities.

“ Exchange Act ” means the Securities Exchange Act of 1934, as amended.

“ Final Prospectus ” means the Statutory Prospectus (including the Incorporated Documents) that discloses the public offering price, other 430B Information and other final terms of the Offered Securities, and otherwise satisfies Section 10(a) of the Act.

“ General Use Issuer Free Writing Prospectus ” means any Issuer Free Writing Prospectus that is intended for general distribution to prospective investors, as evidenced by its being so specified in Schedule B to this Agreement.

“ Incorporated Documents ” means any documents incorporated by reference in the Registration Statement.

“ Issuer Free Writing Prospectus ” means any “issuer free writing prospectus,” as defined in Rule 433, relating to the Offered Securities in the form filed or required to be filed with the Commission or, if not required to be filed, in the form retained in the Company’s records pursuant to Rule 433(g).

“ Limited Use Issuer Free Writing Prospectus ” means any Issuer Free Writing Prospectus that is not a General Use Issuer Free Writing Prospectus.

“ Rules and Regulations ” means the rules and regulations of the Commission.

“ Securities Laws ” means, collectively, the Sarbanes-Oxley Act of 2002 (“ Sarbanes-Oxley ”), the Act, the Exchange Act, the Rules and Regulations, the auditing principles, rules, standards and practices applicable to auditors of “issuers” (as defined in Sarbanes-Oxley) promulgated or approved by the Public Company Accounting Oversight Board and, as applicable, the rules of the New York Stock Exchange (“ Exchange Rules ”).

“ Statutory Prospectus ” with reference to any particular time means the prospectus relating to the Offered Securities that is included in the Registration Statement immediately prior to that time, including all 430B Information and all 430C Information with respect to the Registration Statement.  For purposes of the foregoing definition, 430B Information shall be considered to be included in the Statutory Prospectus only as of the actual time that form of prospectus (including a prospectus supplement) is filed with the Commission pursuant to Rule 424(b) and not retroactively.

Unless otherwise specified, a reference to a “rule” is to the indicated rule under the Act.

(b)   Compliance with Securities Act Requirements .  (i) (A) At the time the Registration Statement initially became effective, (B) at the time of each amendment thereto for the purposes of complying with Section 10(a)(3) of the Act (whether by post-effective amendment, incorporated report or form of prospectus), (C) at the Effective Time relating to the Offered Securities and (D) on the Closing Date, the Registration Statement conformed and will conform, as applicable, in all respects to the requirements of the Act and the Rules and Regulations and did not include and will not include, as applicable, any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein not misleading and (ii) (A) on its date, (B) at the time of filing the Final Prospectus pursuant to Rule 424(b) and (C) on the Closing Date, the Final Prospectus will conform in all material respects to the requirements of the Act and the Rules and Regulations, and will not include any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein not misleading.  The preceding sentence does not apply to statements in or omissions from any such document based upon written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information is that described as such in Section 8(b) hereof.

(c)   Shelf Registration Statement .  The date of this Agreement is not more than three years subsequent to the more recent of the initial effective time of the Registration Statement or December 1, 2005.  If,

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immediately prior to the third anniversary of the more recent of the initial effective time of the Registration Statement or December 1, 2005, any of the Offered Securities remain unsold by the Underwriters, the Company will prior to that third anniversary file, if it has not already done so, a new shelf registration statement relating to the Offered Securities, in a form reasonably satisfactory to the Representatives, will use its best efforts to cause such registration statement to be declared effective within 180 days after that third anniversary, and will take all other action necessary or appropriate to permit the public offering and sale of the Offered Securities to continue as contemplated in the expired registration statement relating to the Offered Securities.  References herein to the Registration Statement shall include such new shelf registration statement.

(d)   Ineligible Issuer Status .  (i)  At the earliest time after the filing of the Registration Statement that the Company or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2)) of the Offered Securities and (ii) at the date of this Agreement, the Company was not and is not an “ineligible issuer,” as defined in Rule 405, including (x) the Company or any other subsidiary in the preceding three years not having been convicted of a felony or misdemeanor or having been made the subject of a judicial or administrative decree or order as described in Rule 405 and (y) the Company in the preceding three years not having been the subject of a bankruptcy petition or insolvency or similar proceeding, not having had a registration statement be the subject of a proceeding under Section 8 of the Act and not being the subject of a proceeding under Section 8A of the Act in connection with the offering of the Securities, all as described in Rule 405.

(e)   Shelf Registration Eligibility .  The Company meets (i) the eligibility criteria for use of Form S-3 under the Act and (ii) the eligibility criteria for use of Form S-3 under the Act as such criteria existed prior to October 21, 1992.

(f)   General Disclosure Package .  As of the Applicable Time, neither (i) the General Use Issuer Free Writing Prospectus(es) issued at or prior to the Applicable Time, the preliminary prospectus supplement, dated September 9, 2009, including the base prospectus, dated July 2, 2009, (which is the most recent Statutory Prospectus distributed to investors generally), and the other information, if any, stated in Schedule B to this Agreement to be included in the General Disclosure Package, all considered together (collectively, the “ General Disclosure Package ”), nor (ii) any individual Limited Use Issuer Free Writing Prospectus, when considered together with the General Disclosure Package, included any untrue statement of a material fact or omitted to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.  The preceding sentence does not apply to statements in or omissions from any Statutory Prospectus or any Issuer Free Writing Prospectus in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 8(b) hereof.

(g)   Issuer Free Writing Prospectuses .  Each Issuer Free Writing Prospectus, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Offered Securities or until any earlier date that the Company notified or notifies Credit Suisse Securities (USA) LLC (“ Credit Suisse ”), Barclays Capital Inc. (“ Barclays ”) and Merrill Lynch, Pierce, Fenner & Smith Incorporated  (together with Credit Suisse and Barclays, the “ Representatives ”) as described in the next sentence, did not, does not and will not include any information that conflicted, conflicts or will conflict with the information then contained in the Registration Statement.  If at any time following issuance of an Issuer Free Writing Prospectus there occurred or occurs an event or development as a result of which such Issuer Free Writing Prospectus conflicted or would conflict with the information then contained in the Registration Statement or as a result of which such Issuer Free Writing Prospectus, if republished immediately following such event or development, would include an untrue statement of a material fact or omitted or would omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, (i) the Company has promptly notified or will promptly notify the Representatives and (ii) the Company has promptly amended or will promptly amend or supplement such Issuer Free Writing Prospectus to eliminate or correct such conflict, untrue statement or omission.  The first sentence of this clause (g) does not apply to statements in or omissions

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from any Issuer Free Writing Prospectus in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 8(b) hereof.

(h)   Good Standing of the Company .  The Company has been duly incorporated and is existing and in good standing under the laws of the State of Delaware, with corporate power and authority to own its properties and conduct its business as described in the General Disclosure Package; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to be so qualified would not, individually or in the aggregate, result in a material adverse effect on the condition (financial or otherwise), results of operations, business or properties of the Company and its subsidiaries taken as a whole (“ Material Adverse Effect ”).

(i)   Subsidiaries .  Each subsidiary of the Company has been duly incorporated or organized and is existing and in good standing under the laws of the jurisdiction of its incorporation or organization, with corporate or business trust power and authority, as applicable, to own its properties and conduct its business as described in the General Disclosure Package; and each subsidiary of the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to be so qualified would not, individually or in the aggregate, result in a Material Adverse Effect; all of the issued and outstanding capital stock of each subsidiary of the Company has been duly authorized and validly issued and is fully paid and nonassessable; and, except as discussed in the General Disclosure Package under the heading “Management’s Discussion and Analysis of Financial Condition and Results of Operation—Liquidity and Capital Resources”, the capital stock of each subsidiary owned by the Company, directly or through subsidiaries, is owned free from liens, encumbrances and defects.

(j)   Offered Securities .  The Offered Securities and all other outstanding shares of capital stock of the Company have been duly authorized; the authorized equity capitalization of the Company is as set forth in the General Disclosure Package; all outstanding shares of capital stock of the Company are, and, when the Offered Securities have been delivered and paid for in accordance with this Agreement on each Closing Date, such Offered Securities will have been, validly issued, fully paid and nonassessable and will conform in all material respects to the information in the General Disclosure Package and to the description of such Offered Securities contained in the Final Prospectus; the stockholders of the Company have no preemptive rights with respect to the Securities; and none of the outstanding shares of capital stock of the Company have been issued in violation of any preemptive or similar rights of any security holder.

(k)   No Finder’s Fee .  There are no contracts, agreements or understandings between the Company and any person that would give rise to a valid claim against the Company or any Underwriter for a brokerage commission, finder’s fee or other like payment in connection with this offering.

(l)   Registration Rights .  Except as disclosed in the General Disclosure Package, there are no contracts, agreements or understandings between the Company and any person granting such person the right to require the Company to file a registration statement under the Act with respect to any securities of the Company owned or to be owned by such person or to require the Company to include such securities in the securities registered pursuant to a Registration Statement or in any securities being registered pursuant to any other registration statement filed by the Company under the Act (collectively, “ registration rights ”), and any person to whom the Company has granted registration rights has agreed not to exercise such rights until after the expiration of the Lock-Up Period referred to in Section 5 hereof.

(m)   Listing .  The Offered Securities have been approved for listing on the New York Stock Exchange, subject to notice of issuance.

(n)   Absence of Further Requirements .  No consent, approval, authorization, or order of, or filing or registration with, any person (including any governmental agency or body or any court) is required for the

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consummation of the transactions contemplated by this Agreement in connection with the offering, issuance and sale of the Offered Securities by the Company, except (i) such as have been obtained or made, (ii) such as may be required under state securities laws and (iii) such as may be required by the Financial Industry Regulatory Authority.

(o)   Title to Property .  Except as disclosed in the General Disclosure Package, the Company and its subsidiaries have good and marketable title to all real properties and good and valid title to all other properties and assets owned by them, in each case free from liens, charges, encumbrances and defects that would, individually or in the aggregate, result in a Material Adverse Effect, and, except as disclosed in the General Disclosure Package, the Company and its subsidiaries hold any leased real or personal property under valid and enforceable leases with no terms or provisions that would, individually or in the aggregate, have a Material Adverse Effect.

(p)   Absence of Defaults and Conflicts Resulting from Transaction .  The execution, delivery and performance of this Agreement and the issuance and sale of the Offered Securities will not result in a breach or violation of any of the terms and provisions of, or constitute a default or a Debt Repayment Triggering Event (as defined below) under, or result in the imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries pursuant to, (i) the charter or by-laws of the Company or any of its subsidiaries, (ii) any law, statute or ordinance, or any rule, regulation, injunction or order of any governmental agency, including without limitation, the United States Food and Drug Administration (the “ FDA ”), or body or any court, domestic or foreign, having jurisdiction over the Company or any of its subsidiaries or any of their properties, or (iii) any agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the properties of the Company or any of its subsidiaries is subject, except, in the case of clauses (ii) or (iii) only, as would not, individually or in the aggregate, result in a Material Adverse Effect; a “ Debt Repayment Triggering Event ” means any event or condition that gives, or with the giving of notice or lapse of time would give, the holder of any note, debenture, or other evidence of indebtedness (or any person acting on such holder’s behalf) the right to require the repurchase, redemption or repayment of all or a portion of such indebtedness by the Company or any of its subsidiaries.

(q)   Absence of Existing Defaults and Conflicts .  Neither the Company nor any of its subsidiaries is in violation of its respective charter, by-laws, or any law, statute or ordinance, or any rule, regulation, injunction or order of any governmental agency, including, without limitation, the FDA, or body or any court, domestic or foreign, having jurisdiction over the Company or any of its subsidiaries or any of their properties, or in default (or with the giving of notice or lapse of time would be in default) under any existing obligation, agreement, covenant or condition contained in any indenture, loan agreement, mortgage, lease or other agreement or instrument to which any of them is a party or by which any of them is bound or to which any of the properties of any of them is subject, except such defaults that would not, individually or in the aggregate, result in a Material Adverse Effect.

(r)   Authorization of Agreement .  This Agreement has been duly authorized, executed and delivered by the Company.

(s)   Possession of Licenses and Permits .  The Company and its subsidiaries possess, and are in compliance with the terms of, all certificates, authorizations, franchises, licenses, permits and other approvals or authorizations of governmental or regulatory authorities, including, without limitation, the FDA (“ Licenses ”), as are necessary to the conduct of the business now conducted or proposed in the General Disclosure Package to be conducted by them, except as would not, individually or in the aggregate, have a Material Adverse Effect, and have not received any notice of proceedings relating to the revocation or modification of any Licenses that, if determined adversely to the Company or any of its subsidiaries, would, individually or in the aggregate, have a Material Adverse Effect.

(t)   Absence of Labor Dispute .  No labor dispute with the employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is imminent that would have a Material Adverse Effect.

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(u)   Possession of Intellectual Property .  The Company and its subsidiaries own, possess, license or can acquire on reasonable terms, adequate trademarks, trade names and other rights to inventions, know-how, patents, copyrights, confidential information and other intellectual property (collectively, “ intellectual property rights ”) necessary to conduct the business now operated by them, or presently employed by them, except as would not, individually or in the aggregate, have a Material Adverse Effect; and have not received any notice of infringement of or conflict with asserted rights of others with respect to any intellectual property rights that, if determined adversely to the Company or any of its subsidiaries, would, individually or in the aggregate, have a Material Adverse Effect.

(v)   Environmental Laws .  Except as disclosed in the General Disclosure Package, neither the Company nor any of its subsidiaries is in violation of any statute, any rule, regulation, decision or order of any governmental agency or body or any court, domestic or foreign, relating to the use, disposal or release of hazardous or toxic substances or relating to the protection or restoration of the environment or human exposure to hazardous or toxic substances  (collectively, “ environmental laws ”), owns or operates any real property contaminated with any substance that is subject to any environmental laws, is liable for any off-site disposal or contamination pursuant to any environmental laws, or is subject to any claim relating to any environmental laws, which violation, contamination, liability or claim would individually or in the aggregate have a Material Adverse Effect; and the Company is not aware of any pending investigation which might lead to such a claim.

(w)   Accurate Disclosure .  The statements in the General Disclosure Package and the Final Prospectus under the headings “Summary of the Offering and Our Common Stock”, “Description of Capital Stock”, “Description of Enhanced Income Securities (EISs)” and “Management’s Discussion and Analysis of Financial Condition and Results of Operation—Liquidity and Capital Resources— Debt ”, as modified by the Company’s current report on Form 8-K filed on August 10, 2009, insofar as such statements summarize legal matters, agreements, documents or proceedings discussed therein, are accurate and fair summaries of such legal matters, agreements, documents or proceedings and present the information required to be shown under applicable Securities Laws.

(x)   Absence of Manipulation .  The Company has not taken, directly or indirectly, any action that is designed to or that has constituted or that would reasonably be expected to cause or result in the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Offered Securities.

(y)   Statistical and Market-Related Data .  Any third-party statistical and market-related data included or incorporated by reference in a Registration Statement, a Statutory Prospectus or the General Disclosure Package are based on or derived from sources that the Company believes to be reliable and accurate.

(z)   Internal Controls and Compliance with the Sarbanes-Oxley Act .  Except as set forth in the General Disclosure Package, the Company, its subsidiaries and the Company’s Board of Directors (the “ Board ”) are in compliance with Sarbanes-Oxley and all applicable Exchange Rules.  The Company maintains a system of internal controls, including, but not limited to, disclosure controls and procedures, internal controls over accounting matters and financial reporting, an internal audit function and legal and regulatory compliance controls (collectively, “ Internal Controls ”) that comply with Sarbanes-Oxley, the Act, the Exchange Act, the Rules and Regulations and the Exchange Rules and are sufficient to provide reasonable assurances that (i) transactions are executed in accordance with management’s general or specific authorizations, (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with accounting principles generally accepted in the United States and to maintain accountability for assets, (iii) access to assets is permitted only in accordance with management’s general or specific authorization and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences.  The Internal Controls are overseen by the Audit Committee (the “ Audit Committee ”) of the Board in accordance with Exchange Rules.  Except as disclosed in the General Disclosure Package, since January 3, 2009, the Company has not publicly disclosed or reported to the Audit Committee or the Board, and within the next 90 days the Company does not reasonably expect to publicly disclose or report to the Audit Committee or

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the Board, (A) a significant deficiency, (B) a material weakness, (C) change in Internal Controls that has materially affected, or is reasonably likely to materially affect, the Company’s Internal Controls, (D) fraud involving management or other employees who have a significant role in Internal Controls, (E) any violation of, or failure to comply with, the Securities Laws, or (F) any other matter involving Internal Controls, except, in the case of (A) and (F), as would not reasonably be expected to have a Material Adverse Effect.

(aa)   Litigation .  Except as disclosed in the General Disclosure Package, there are no pending actions, suits or proceedings (including any inquiries or, to the Company’s knowledge, investigations by any court or governmental agency or body, domestic or foreign) against or affecting the Company, any of its subsidiaries or any of their respective properties that, if determined adversely to the Company or any of its subsidiaries, would individually or in the aggregate have a Material Adverse Effect, or would materially and adversely affect the ability of the Company to perform its obligations under this Agreement, or which are otherwise material in the context of the sale of the Offered Securities; and no such actions, suits or proceedings (including any inquiries or investigations by any court or governmental agency or body, domestic or foreign) are, to the Company’s knowledge, threatened or contemplated.

(bb)   Financial Statements .  The financial statements included in, or incorporated by reference into, the Registration Statement and the General Disclosure Package present fairly the financial position of the Company and its consolidated subsidiaries as of the dates shown and their results of operations and cash flows for the periods shown, and such financial statements have been prepared in conformity with the generally accepted accounting principles in the United States applied on a consistent basis.

(cc)   No Material Adverse Change in Business .  Except as disclosed in the General Disclosure Package, since the end of the period covered by the latest audited financial statements included in, or incorporated by reference into, the General Disclosure Package (i) there has been no material adverse change, nor any development or event involving a prospective material adverse change, in the condition (financial or otherwise), results of operations, business, properties or prospects of the Company and its subsidiaries, taken as a whole, (ii) except as disclosed in or contemplated by the General Disclosure Package, there has been no dividend or distribution of any kind declared, paid or made by the Company on any class of its capital stock and (iii) except as disclosed in or contemplated by the General Disclosure Package, there has been no material adverse change in the capital stock, short-term indebtedness, long-term indebtedness, net current assets or net assets of the Company and its subsidiaries.

(dd)   Investment Company Act .  The Company is not and, after giving effect to the offering and sale of the Offered Securities and the application of the proceeds thereof as described in the General Disclosure Package, will not be an “investment company” as defined in the Investment Company Act of 1940 (the “ Investment Company Act ”).

(ee)   Ratings .  No “nationally recognized statistical rating organization” as such term is defined for purposes of Rule 436(g)(2) (i) has imposed (or has informed the Company that it is considering imposing) any condition (financial or otherwise) on the Company’s retaining any rating assigned to the Company or any securities of the Company or (ii) has indicated to the Company that it is considering any of the actions described in Section 7(c)(ii) hereof.

(ff)   Taxes.  The Company and its subsidiaries have filed all federal, state, local and non-U.S. tax returns that are required to be filed or have requested extensions thereof (except in any case in which the failure so to file would not have a Material Adverse Effect); and, except as set forth in the General Disclosure Package, the Company and its subsidiaries have paid all taxes (including any assessments, fines or penalties) required to be paid by them, except for any such taxes, assessments, fines or penalties currently being contested in good faith or as would not, individually or in the aggregate, have a Material Adverse Effect.

(gg)   Insurance.  The Company and its subsidiaries are insured by insurers with appropriately rated claims paying abilities against such losses and risks and in such amounts as are prudent and customary for

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the businesses in which they are engaged; all policies of insurance insuring the Company or any of its subsidiaries or their respective businesses, assets, employees, officers and directors are in full force and effect; and neither the Company nor any such subsidiary has any reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business at a cost that would not have a Material Adverse Effect, except as set forth in or contemplated in the General Disclosure Package.

(hh)   Compliance.  Each of the Company, its subsidiaries, its affiliates and any of their respective officers, directors, supervisors, managers, agents, or employees, has not violated, its participation in the offering will not violate, and it has instituted and maintains policies and procedures designed to ensure continued compli