LICENSE AGREEMENT

Exhibit 10.1

CERTAIN MATERIAL (INDICATED BY AN ASTERISK) HAS BEEN OMITTED FROM THIS DOCUMENT PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT. THE OMITTED MATERIAL HAS BEEN FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

EXECUTION VERSION

LICENSE AGREEMENT

THIS LICENSE AGREEMENT (this “ Agreement ”) is entered into as of the 10th day of June, 2009 (the “ Effective Date ”) by and between SmithKline Beecham Corporation, doing business as GlaxoSmithKline, a Pennsylvania corporation located at One Franklin Plaza, Philadelphia, PA 19102 (“ SB ”), Glaxo Group Limited, a private limited company incorporated in England and Wales, having its registered office at Glaxo Wellcome House, Berkeley Avenue, Greenford, Middlesex, England UB6 0NN (“ GGL ,” and together with SB, “ GSK ”) and Orexigen Therapeutics, Inc., a Delaware corporation located at 3344 N. Torrey Pines Court, Suite 200, La Jolla, California 92037 (“ Orexigen ”). GSK and Orexigen are sometimes collectively referred to herein as the “ Parties ” and separately as a “ Party .”

WHEREAS, GSK is the owner of all right, title and interest in and to the Licensed Patents (as hereinafter defined); and

WHEREAS, Orexigen desires to obtain a non-exclusive license from GSK under the aforesaid Licensed Patents to develop and commercialize Licensed Product in the Field in the Territory (as each such term is hereinafter defined) as set forth herein, and GSK is willing to grant Orexigen such license.

NOW, THEREFORE, in consideration of the mutual covenants and agreements set forth herein and other good and valuable consideration, the receipt and legal sufficiency of which are hereby mutually acknowledged, Orexigen and GSK hereby agree as follows:

Article 1. Definitions .

Section 1.1 As used herein, the following capitalized terms will have the meanings set forth below when used in this Agreement, and all terms defined in the singular will have the same meanings when used in the plural (and vice versa), unless otherwise specified.

“ AAA ” will have the meaning set forth in Section 10.1.

“ Affiliate(s) ” of a Party or Person means any Person(s), whether directly or indirectly, Controlling, Controlled by, or under common Control with, such Party or Person, as applicable.

“ Agreement ” will have the meaning set forth in the Preamble.

“ Applicable Law ” means all provisions of any and all federal, national, state, provincial or local statutes, laws, rules, regulations, administrative codes, ordinances, decrees, orders, decisions, injunctions, awards judgments, permits and licenses of or from governmental authorities in the Territory that apply to the use or regulation of the Licensed Product.

“ Business Day ” means any day other than a day that is a Saturday, a Sunday, a federal holiday in the United States.

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“ Change of Control ” means the occurrence of any of the following events:

(a) a merger or consolidation of Orexigen with or into any other corporation or other entity or person;

(b) a sale, exchange or other transfer in one transaction or a series of related transactions of all or substantially all of Orexigen’s assets;

(c) a liquidation or dissolution of Orexigen; or

(d) a sale or transfer of Orexigen’s voting securities in one transaction or a series of related transactions that will result in the transfer of ownership of fifty percent (50%) or more of the voting securities of Orexigen or in one Person or an affiliated group of Persons owning fifty percent (50%) or more of the voting securities of Orexigen;

provided , that the following events shall not constitute a “Change of Control”: (i) a merger, sale, transfer or consolidation of Orexigen in which the holders of the voting securities of Orexigen immediately prior to the merger, sale, transfer or consolidation hold at least a majority of the voting securities in the successor corporation immediately after the merger or consolidation; (ii) a sale, lease, exchange or other transaction in one transaction or a series of related transactions of all or substantially all of Orexigen’s assets to a wholly owned subsidiary corporation; (iii) a mere reincorporation of Orexigen; or (iv) a transaction undertaken for the sole purpose of creating a holding company that will be owned in substantially the same proportion by the persons who held Orexigen’s securities immediately before such transaction; provided further, that in the cases of clauses (ii), (iii) and (iv), such subsidiary, reincorporated entity or holding company shall sign a joinder to this Agreement agreeing to be jointly and severally responsible for all of Orexigen’s obligations and liabilities hereunder.

“ Claim ” has the meaning set forth in Section 10.2.

“ Confidential Information ” means any and all information disclosed to or obtained by the Parties pursuant to or in connection with the negotiation, execution, delivery and performance of this Agreement or the consummation of the transactions contemplated hereby and any and all information regarding, related to, or associated with any or all elements of this Agreement including the Licensed Patents; provided, however, that Confidential Information will not include information that: (i) at the time of disclosure is in the public domain; (ii) after disclosure becomes part of the public domain, except through breach of this Agreement; (iii) a Party can demonstrate by reasonable proof was in its possession prior to the time of disclosure by the other Party hereunder, and was not acquired directly or indirectly from the other Party; (iv) a Party can demonstrate by reasonable proof was developed by or on behalf of such Party independent of and without reference to the other Party’s Confidential Information; or (v) becomes available to a Party from a Third Party who did not acquire such information directly or indirectly from the other Party and who is not otherwise prohibited from disclosing such information.

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“ Control ” means (i) direct or indirect ownership of more than fifty percent (50%) of the equity (or such lesser percentage that is the maximum allowed to be owned by a foreign corporation in a particular jurisdiction) having the power to vote on or direct the affairs of such Party or Person, as applicable, or (ii) the power to direct decisions of such Party or Person, as applicable, including, without limitation, the power to direct management and policies of such Party or Person, as applicable, whether by reason of ownership, by contract or otherwise (and the expressions “ Controlling ” and “ Controlled ” shall be construed accordingly).

“ Disclosing Party ” will have the meaning set forth in Section 5.1.

“ Dispute ” will have the meaning set forth in Section 10.1.

“ Dispute Notice ” will have the meaning set forth in Section 10.1.

“ Effective Date ” will have the meaning set forth in the Preamble.

“ FDA ” means the United States Food and Drug Administration.

“ Field ” means the treatment of obesity and disorders of weight management.

“ GSK ” will have the meaning set forth in the Preamble.

“ GSK Indemnitees ” will have the meaning set forth in Section 10.2.

“ Indemnitee ” will have the meaning set forth in Section 10.4.

“ Indemnitor ” will have the meaning set forth in Section 10.4.

“ Licensed Patents ” means (i) [***]; any foreign equivalents of the aforesaid patents; any patents claiming priority therefrom or common priority therewith; and all divisions, continuations, continuations-in-part, provisionals, reissues, reexaminations, substitutions or extensions thereof, whether foreign or domestic, and any patents that issue thereon, and any reissues, reexaminations renewals or extensions (including any supplemental protections certificate) of any such patent, including all foreign counterparts of any of the foregoing.

“ Licensed Product ” means the prescription pharmaceutical product owned or controlled by Orexigen with the trade name “Contrave ^® ” and [***].

“ Losses ” will have the meaning set forth in Section 10.2.

“ Major Market ” means any of the United Kingdom, Germany, France, Italy and Spain.

“ New Drug Application ” means a New Drug Application filed with the FDA including a 505(b)(2) application.

“ Orexigen ” will have the meaning set forth in the Preamble.

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“ Orexigen Indemnitees ” will have the meaning set forth in Section 10.3.

“ Product Partnering Agreement ” will have the meaning set forth in Section 3.1.

“ Party ” or “ Parties ” will have the meaning set forth in the Preamble.

“ Person ” means any individual, corporation, partnership, firm, association, joint venture, joint stock company, trust or other entity, or any government or regulatory administrative or political subdivision or agency, department or instrumentality thereof.

“ Receiving Party ” will have the meaning set forth in Section 5.1.

“Regulatory Approval” means marketing approval from the FDA or from agencies in foreign jurisdictions that provide approval for marketing or distributing drugs in those jurisdictions.

“ Royalty(ies) ” will have the meaning set forth in Section 3.1.

“ Sublicense ” means the sublicense agreement with any Sublicensee.

“ Sublicensee ” will have the meaning set forth in Section 2.2.

“ Term ” will have the meaning set forth in Section 8.1.

“ Territory ” means all countries and territories in the world.

“ Third Party ” means any Person other than the Parties.

“ Trade Dress ” means any and all designs, colors, graphics and Trademarks of Licensed Product packaging, these elements either separately or together in combination thereof.

“ Trademark ” means any and all trademarks, service marks, words, phrases, slogans, designs, logos and combinations thereof used as an indication of source of Licensed Product or associated services or products.

“ United States ” or “ U.S. ” means the fifty (50) states of the United States of America, its territories and the District of Columbia.

Section 1.2 The word “ including ” or any variation thereof means “including without limitation” and will not be construed to limit any general statement that it follows to the specific or similar items or matters immediately following it.

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Article 2. Patent License Grant; Covenant Not to Sue.

Section 2.1 Non-Exclusive Patent License Grant .

(i) Subject to the terms and conditions of this Agreement, including, without limitation, Section 11.3(vi), GSK, on behalf of itself and its Affiliates, hereby grants to Orexigen a non-exclusive license, with the right to grant sublicenses solely for the purposes as set forth in Section 2.2, under the Licensed Patents, to make, have made, use, sell, offer for sale and import and to file for and obtain Regulatory Approval for Licensed Product in the Field in the Territory.

(ii) Without prejudice to the provisions of Section 2.5, Orexigen expressly acknowledges and agrees that except as set forth in Section 2.1(i), neither GSK nor any of its Affiliates is in any way granting to Orexigen or any of its Affiliates or Sublicensees any rights under any patents or patent applications other than the Licensed Patents that are or may become owned by GSK or any of its Affiliates, or to which GSK or any of its Affiliates otherwise has, now or in the future the right to grant licenses and license rights or sublicenses and sublicense rights. Further, Orexigen expressly acknowledges and agrees that (a) the non-exclusive license under the Licensed Patents granted by GSK to Orexigen as provided in Section 2.1(i) is solely with respect to the making, having made, using, selling, offering for sale and importing of and filing for and obtaining Regulatory Approval of Licensed Product in the Field in the Territory; and (b) the non-exclusive license under the Licensed Patents granted by GSK to Orexigen as provided in Section 2.1(i) is in no way deemed directly or impliedly to be a license under, and Orexigen disclaims all direct or implied rights under, the Licensed Patents or any other patents that, in each case, are or may become owned by GSK or any of its Affiliates, or to which GSK or any of its Affiliates otherwise has, now or in the future, that are related to, regarding or associated in any way with the making, having made, using, selling, offering for sale or importing of any pharmaceutical product or formulation within and without the Field and within and without the Territory, other than the Licensed Product.

Section 2.2 Sublicense of Rights . Subject to the terms and conditions of this Agreement, the Parties agree that Orexigen may (without the consent of GSK) sublicense, without the right to further sublicense, any or all of its rights under this Agreement (including but not limited to those set forth in Section 2.1) to a Third Party solely (i) in connection with Regulatory Approval for the Licensed Product for Orexigen or (ii) in connection with a Product Partnering Agreement (any such party, a “ Sublicensee ”). Orexigen acknowledges and agrees that in no event will the Sublicense to any Sublicensee of any or all of its rights under this Agreement be deemed to relieve Orexigen of its liabilities or obligations to GSK under this Agreement. Orexigen expressly acknowledges and agrees that it will remain fully and unconditionally obligated and responsible for the full and complete performance of all of its obligations under the terms and conditions of this Agreement. In the event that Orexigen elects to sublicense as provided in this Section 2.2(ii), it will provide GSK with written notice thereof, which notice will include the identity and address of any Sublicensee, prior to the execution of any such Sublicense by Orexigen. Orexigen represents and warrants that the terms of any such Sublicense will refer to this Agreement and Orexigen shall ensure that none of the terms of such Sublicense shall conflict with the terms of this Agreement. In the event of a conflict between the terms of this Agreement and the terms of such Sublicense, as between Orexigen and GSK, and/or as to any rights and/or obligations under this Agreement that are sublicensed to any Sublicensee as provided herein, the terms of this Agreement will prevail.

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Section 2.3 Affiliates . Either Party may contract or agree with one or more of its Affiliates to have such Affiliate perform any of such Party’s obligations herein. In no event will such use of an Affiliate be deemed to relieve a Party of its liabilities or obligations to the other Party under this Agreement. Each Party expressly acknowledges and agrees that it will remain fully and unconditionally obligated and responsible for the full and complete performance of all of its obligations under the terms and conditions of this Agreement, whether or not such performance is carried out by such Party or any of its Affiliates.

Section 2.4 Covenant Not to Sue of Orexigen . During the term of this Agreement (and as further provided in Section 8.4), Orexigen represents and warrants that neither it nor any of its Affiliates will initiate or bring, nor will it or any of its Affiliates assist in any way any Person in pursuing, a lawsuit, proceeding, interference or any other action of any kind whatsoever that either (i) seeks a judicial determination that the Licensed Product does not infringe on any of the Licensed Patents, or (ii) challenges the validity, enforceability or scope of any of the Licensed Patents, provided , that this Section 2.4 shall not apply in the event that GSK or any of its Affiliates breaches the covenant not to sue in Section 2.5.

Section 2.5 Covenant Not to Sue of GSK . During the term of this Agreement, GSK represents and warrants that neither it nor any of its Affiliates will, under the Licensed Patents, initiate or bring a lawsuit, proceeding or other action of any kind whatsoever that claims that the making, having made, using, selling, offering for sale or importing, or seeking, obtaining or maintaining Regulatory Approval of, Licensed Product in the Field in the Territory by Orexigen, any of its Affiliates or any permitted Sublicensee is infringing the Licensed Patents, provided , that this Section 2.5 shall not apply in the event that Orexigen or any of its Affiliates breaches the covenant not to sue in Section 2.4.

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Article 3. Royalty Payments to GSK .

Section 3.1 Royalties . In consideration for the non-exclusive license under the Licensed Patents granted to Orexigen by GSK pursuant to Section 2.1, Orexigen will make the following royalty payments (the “ Royalties ”) to GSK in the amounts and in the manner specified below, within [***] ([***]) days after the milestones specified below:

Section 3.2 Royalty Payment Provisions .

(i) All Royalties are non-refundable.

(ii) All Royalties shall be paid by Orexigen, in U.S. Dollars, by wire transfer of immediately available funds to GSK’s account listed on Exhibit A , or to such other account as GSK designates in writing to Orexigen. Orexigen shall send written confirmation of such payments of Royalties at the time they are made to the addresses set forth in Section 11.1.

(iii) In no event shall Orexigen have any right to reclaim any Royalties already paid to GSK.

(iv) The Royalties shall be internally allocated by GSK as follows: [***]% to SB and [***]% to GGL.

Article 4. Product Development and Commercialization . As of the Effective Date and during the Term, Orexigen will have full control, authority and responsibility over research, development, registration, manufacture, commercialization, marketing and sale of all Licensed Product in each country in the Field in the Territory, and all such activity will be undertaken at Orexigen’s sole expense and discretion.

Article 5. Confidential Information .

Section 5.1 Confidential Information . During the Term, and for a period of five (5) years after the effective date of the expiration or earlier termination of this Agreement for any permitted reason contained herein, the Parties agree that:

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(i) The Parties will not disclose, directly or indirectly, in any manner whatsoever to any Third Parties any Confidential Information received from the other Party (the “ Disclosing Party ”) without first obtaining the written consent of the Disclosing Party which such consent shall not be unreasonably withheld, conditioned or delayed, and the Parties will keep confidential, all of the Disclosing Party’s Confidential Information that is disclosed to such Party (the “ Receiving Party ”), provided that a Party may disclose the specific terms of this Agreement (a) to attorneys, accountants, advisors, lenders, investors and bona fide prospective lenders and investors who are bound by obligations of confidentiality no less restrictive than those set forth herein or who are otherwise bound by ethical or other similar obligations, or (b) pursuant to business discussions wherein a letter of intent or binding agreement has been executed or a term sheet has been completed relating to a sale of substantially all the assets of Orexigen, an equity investment in Orexigen, a merger, a sublicense permitted hereunder, or a Change of Control, so long as such discussions are subject to a nondisclosure agreement. The Receiving Party agrees to use the same level of care in safeguarding the Disclosing Party’s Confidential Information that the Receiving Party uses with its own confidential information of a similar nature, but in no event less than reasonable care. The Receiving Party will restrict disclosure of the Disclosing Party’s Confidential Information solely to those of its (or its Affiliates’ or any Sublicensee’s) employees or representatives having a need to know such Confidential Information in order to accomplish the purposes of this Agreement. The Receiving Party represents that its employees and representatives who will have access to the Disclosing Party’s Confidential Information are bound by an obligation to maintain such Confidential In