COLLABORATIVE RESEARCH AND LICENSE AGREEMENT

Exhibit 10.41 COLLABORATIVE RESEARCH AND LICENSE AGREEMENT between ARCHEMIX CORP. and ELAN PHARMA INTERNATIONAL, LIMITED June 30, 2006 CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

TABLE OF CONTENTS

CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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COLLABORATIVE RESEARCH AND LICENSE AGREEMENT      This COLLABORATIVE RESEARCH AND LICENSE AGREEMENT (this "Agreement") is entered into as of June 30, 2006, by and between Archemix Corp., a Delaware corporation with offices at 300 Third Street, Cambridge, MA 02142 ("ARCHEMIX"), and Elan Pharma International Limited, a private company limited by shares organized under the laws of Ireland with offices at Monksland, Athlone, County Westmeath, Ireland ("ELAN"). Each of ELAN and ARCHEMIX is sometimes referred to individually herein as a "Party" and are sometimes referred to collectively as the "Parties."      WHEREAS, ARCHEMIX has developed and controls certain technology, patent rights and proprietary materials related to (a) its proprietary IL-23 aptamers, (b) the identification and optimization of other aptamers using its proprietary SELEX™ process and SELEX™ technology, and (c) the use of such aptamers for treating, preventing or delaying onset or progression of human diseases or conditions; and      WHEREAS, ELAN is engaged in the research, development and commercialization of human therapeutics; and      WHEREAS, the Parties desire to enter into a collaboration for the purposes of (a) further developing and commercializing ARCHEMIX’ IL-23 aptamers and (b) identifying aptamers against targets that fulfill certain criteria, and developing and commercializing products derived from such aptamers for the prevention, treatment and delay of onset or progression of disease.      NOW, THEREFORE, in consideration of the mutual covenants contained herein, and for other good and valuable consideration, the Parties hereto, intending to be legally bound, hereby agree as follows: 1. DEFINITIONS      Whenever used in this Agreement with an initial capital letter, the terms defined in this Section 1, Schedule 4 and elsewhere throughout the Agreement shall have the meanings specified. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

     1.1 " AAA " means the American Arbitration Association.      1.2 " Adverse Event " means any untoward, undesired or unplanned medical occurrence in a human clinical trial subject or a patient, which occurrence has a temporal relationship to administration of a Clinical Candidate or Product, whether or not considered related to the Clinical Candidate or Product, including, without limitation, any undesirable sign (including abnormal laboratory findings of clinical concern), symptom or disease that may be associated with the use of such Clinical Candidate or Product.      1.3 " Affiliate " means, with respect to any Person, any other Person that, directly or indirectly, controls, or is controlled by, or is under common control with, such Person. For purposes of this definition, "control" means (a) ownership of fifty percent (50%) or more of the shares of stock entitled to vote for the election of directors in the case of a corporation, fifty percent (50%) or more of the equity interests in the case of any other type of legal entity, (b) status as a general partner in any partnership, or (c) any other arrangement whereby a Person controls or has the right to control the board of directors of a corporation or equivalent governing body of an entity.      1.4 " [***] Agreement " means any transaction (including any partnership or strategic alliance) between ARCHEMIX and a Third Party for the purpose of licensing that Third Party or collaborating with that Third Party to identify, develop and commercialize therapeutic Aptamers against [***] for the treatment of [***] diseases, but excluding (a) any transaction with a Third Party involving any fee-for-service or sponsored research agreement or arrangement relating to performance of services (including manufacturing) or research by a Third Party solely for ARCHEMIX, or (b) any agreement or arrangement involving the payment to ARCHEMIX or any of its Affiliates of governmental research or grant funding or research or grant funding from a non-profit organization in the absence of a license, collaboration or similar agreement.      1.5 " [***] " or " [***] " means the cleavage product of the [***] occurring predominantly as the [***], as described in [***].      1.6 " Annual Development Plan " means, with respect to each Clinical Candidate and Contract Year, the written plan for the Development of such Clinical Candidate for such Contract CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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Year, as such written plan may be amended, modified or updated, as further described in section 4.3.      1.7 " Annual Net Sales " means, with respect to any Calendar Year, the aggregate amount of the Net Sales during such Calendar Year.      1.8 " Annual Research Plan " means the written plan describing the activities to be carried out by each Party during each Contract Year of the Research Program Term in conducting the Research Program pursuant to this Agreement, as prepared by the JPT and approved by the JMC, and as such written plan may be amended, modified or updated, as further described in Section 3.2.      1.9 " Applicable Laws " means federal, state, local, national and supra-national laws, statutes, rules and regulations, including any rules, regulations or requirements of Regulatory Authorities, national securities exchanges or securities listing organizations, that are in effect from time to time during the Term and apply to a particular activity hereunder.      1.10 " Aptamer " means (i) any naturally or non-naturally occurring oligonucleotide identified by ARCHEMIX through the SELEXÔ Process that binds with high specificity and affinity to a Target; and (ii) any oligonucleotide Derived from the oligonucleotide of (i) that has such high specifity and affinity.      1.11 " Aptamer-Generic Patent Rights " means Patent Rights that cover only Aptamer-Generic Technology.      1.12 " Aptamer-Generic Technology " means any Technology relating generally to aptamers, or their methods of use, that is not Program Aptamer Specific Technology.      1.13 " ARCHEMIX Annual FTE Commitment " means the annual FTE commitment of ARCHEMIX to the Research Program, which shall equal [***] FTEs per Contract Year, unless otherwise agreed by the Parties.      1.14 " ARCHEMIX Background Technology " means any Technology that is used by ARCHEMIX, or provided by ARCHEMIX for use, or that is otherwise necessary or useful in the performance of the Research Program, the Development or Co-Development of Lead Compounds, Clinical Candidates and/or the Commercialization of Products that is (a) Controlled by CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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ARCHEMIX as of the Effective Date or (b) Made by employees of, or consultants to, ARCHEMIX after the Effective Date other than in the conduct of ARCHEMIX Research Activities or ARCHEMIX Development Activities and without the use in a material respect of any ELAN Technology, ELAN Materials, ELAN Patent Rights, ELAN Product Patent Rights, ELAN Product Technology or Program Technology. For purposes of clarity, ARCHEMIX Background Technology (a) shall include the SELEX™ Process and SELEX™ Technology and (b) shall not include, and shall not be included in, ARCHEMIX Program Technology or ARCHEMIX’ interest in Joint Technology.      1.15 " ARCHEMIX Co-Development Percentage " means a whole number percentage less than or equal to [***] percent ([***]%) and greater than or equal to [***] percent ([***]%) specified by ARCHEMIX pursuant to Sections 4.11.1 and 4.11.2.      1.16 " ARCHEMIX Decision " means a decision with respect to the following issues: (a) how to perform the [***] against [***] identified for inclusion in the Research Program in accordance with Section 3.5.1; (b) the expansion, [***], of the number of FTEs to be provided by ARCHEMIX under the Research Program in any Contract Year beyond the ARCHEMIX Annual FTE Commitment (including without limitation, the application of additional ARCHEMIX FTEs beyond the ARCHEMIX Annual FTE Commitment to the [***]); (c) any activity requiring ARCHEMIX to apply significantly (i.e., at least [***]%) more resources (other than FTEs) to the Research Program than are specified by the Annual Research Plan; (d) to incur any [***] except as provided in Section 3.3.5; (e) whether ELAN has nominated as a Program Target a Target that ARCHEMIX determines in good faith, after consultation with, and, if requested by ELAN, obtaining a letter from, ARCHEMIX’ outside counsel (which counsel shall be of nationally recognized reputation in the life sciences field) confirming such determination, that an executed written agreement between ARCHEMIX and a Third Party prohibits ARCHEMIX from allowing ELAN to designate such Target as a Program Target; provided, that, to the extent permitted by any such agreement, ARCHEMIX shall provide ELAN with a redacted copy of such agreement which shall include those provisions that are reasonably relevant to such determination, subject to the confidentiality obligations hereunder; and (f) whether ARCHEMIX should [***] obtain a license to a Blocking Third Party Patent or any other Third Party Patent Rights. Notwithstanding CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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the foregoing, the characterization of the matters described in Section 1.16(b) above as an ARCHEMIX Decision shall not affect the agreement of ARCHEMIX to reasonably consider in good faith using its commercially reasonable discretion any requests of ELAN to increase the number of ARCHEMIX FTEs to be provided in the Research Program beyond the ARCHEMIX Annual FTE Commitment or to increase other resources to be utilized by ARCHEMIX in the Research Program.      1.17 " ARCHEMIX Development Activities " means all Development or Co-Development activities specified to be conducted by ARCHEMIX in any Annual Development Plan (or amendment thereto) and approved by ARCHEMIX’ representatives on the JMC.      1.18 " ARCHEMIX Field " means the use of Aptamers for all therapeutic purposes and applications.      1.19 " ARCHEMIX-Gilead License Agreement " means the License Agreement between Gilead Sciences, Inc. and ARCHEMIX dated October 21, 2001, and any amendments thereto.      1.20 " ARCHEMIX Materials " means any Proprietary Materials that are Controlled by ARCHEMIX and used by ARCHEMIX, or provided by ARCHEMIX for use, in the Research Program, the Development Program and/or any other activities conducted hereunder, and that are not Joint Technology or Program Technology. For purposes of clarity, ARCHEMIX Materials shall include all Aptamers Controlled by ARCHEMIX and provided by ARCHEMIX for use in the Research Program and/or for the Development of Clinical Candidates that are not Joint Technology or Program Technology.      1.21 " ARCHEMIX Patent Rights " means any Patent Rights Controlled by ARCHEMIX that contain one or more claims that cover ARCHEMIX Technology.      1.22 " ARCHEMIX Program Technology " means any Program Technology that (a) is not ELAN Product Technology or Joint Technology, (b) is Made by or through employees of, or consultants to, ARCHEMIX, alone or with a Third Party, and (c) does not use in a material respect or benefit in a material respect from any ELAN Technology, ELAN Product Technology, ELAN Product Patent Rights, ELAN Materials, ELAN Patent Rights or Joint Technology. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     1.23 " ARCHEMIX Research Activities " means all activities specified to be conducted by ARCHEMIX in any Annual Research Plan (or amendment thereto) that are (a) approved by the JMC and (b) to the extent involving matters that are ARCHEMIX Decisions, approved by ARCHEMIX in accordance with Section 2.1.5.      1.24 " ARCHEMIX-SomaLogic Agreement " means the License Agreement by and between ARCHEMIX and SomaLogic, Inc. dated as of September 4, 2003, and any amendments thereto.      1.25 " ARCHEMIX Technology " means, collectively, ARCHEMIX Background Technology and ARCHEMIX Program Technology.      1.26 " Calendar Year " means each successive period of twelve (12) months commencing on January 1 and ending on December 31.      1.27 " Change of Control " means, with respect to a Party, (a) a merger, consolidation, share exchange or other similar transaction involving such Party and any Third Party which results in the holders of the outstanding voting securities of such Party immediately prior to such merger, consolidation, share exchange or other similar transaction ceasing to hold more than fifty percent (50%) of the combined voting power of the surviving, purchasing or continuing entity immediately after such merger, consolidation, share exchange or other similar transaction, (b) any transaction or series of related transactions (other than an investment transaction by an entity not engaged in the pharmaceutical or biotechnology business, the purpose of which is to raise capital for a Party) in which a Third Party, together with its Affiliates, becomes the beneficial owner of fifty percent (50%) or more of the combined voting power of the outstanding securities of such Party, or (c) the sale or other transfer to a Third Party of all or substantially all of such Party’s assets which relate to this Agreement.      1.28 " Clinical Candidate Selection Criteria " or " CCSC " means the guideline criteria for selecting Lead Compounds that are sufficiently promising to warrant further Development as Clinical Candidates (a) as set forth in Schedule 7 attached hereto for IL-23, and (b) as such Schedule 7 shall be amended from time to time by the JMC with respect to the other Program Targets listed on Schedule 1 as of the Effective Date and/or to any other Program Target CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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to be included in the Research Program, which amendment shall occur before any activities with respect to such Program Target are initiated, in any material respect, in the Research Program.      1.29 " Co-Developed Product " means a Psoriatic Diseases Co-Developed Product and/or a Non-Parenteral Co-Developed Product.      1.30 " Co-Development " means Development of a Co-Developed Product after ARCHEMIX’ exercise of a Co-Development Option as described in Section 4.11.1.      1.31 " Co-Development Territory " means any or all of: (a) the United States of America and its territories and possessions; (b) all countries that comprise the European Union; and/or (c) all countries other than those described in (a) or (b).      1.32 " Collaboration " means the alliance of ARCHEMIX and ELAN established pursuant to this Agreement for the purposes of identifying, researching and Developing Collaboration Aptamers and Commercializing Products in the Territory.      1.33 " Collaboration Aptamer " means any or all of IL-23 Aptamers, Development Leads, Collaboration Compounds, Program Aptamers, Patented Aptamers, Lead Compounds, Clinical Candidates and/or Products.      1.34 " Collaboration Compound " means any Program Aptamer that binds a Program Target other than IL-23 that is identified by performing the SELEX™ Process against a Program Target other than IL-23 in the conduct of the Research Program or any Aptamer Derived therefrom that binds a Program Target other than IL-23.      1.35 " Collaboration Product " means any pharmaceutical or medicinal item, substance or formulation that contains, incorporates or comprises a Collaboration Compound or any Aptamer Derived therefrom that binds a Program Target other than IL-23.      1.36 " Combination Product " means a combination or bundled product that is sold together in a single package or as a unit at a single price by a Party, its Affiliate or Sublicensee and that includes: (a) a Product; and (b) a Supplemental Product that is not within the Licensed Patent Rights, where both the Product and the Supplemental Product are required to treat the intended Indication and/or to achieve the intended use or effect. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     1.37 " Commercialization " means any and all activities related to the offering for sale and/or sale of a Product after Commercialization Regulatory Approval has been obtained, including but not limited to activities related to marketing, manufacturing for commercial distribution, educating providers and consumers, contracting, pharmacoeconomics studies, payer reimbursement, promoting, detailing, distributing, importing, conducting post-marketing human clinical studies and interacting with Regulatory Authorities regarding the foregoing. When used as a verb, to "Commercialize" or "Commercializing" means to engage in Commercialization and "Commercialized" has a corresponding meaning.      1.38 " Commercially Reasonable Efforts " means (a) with respect to activities of ARCHEMIX in the Research Program, or, with respect to the conduct of ARCHEMIX Development Activities, or the Commercialization of Co-Developed Products, if any, the efforts and resources comparable to those undertaken by ARCHEMIX in pursuing the research, discovery, development and intellectual property protection of proprietary materials and the development of product candidates and commercialization of products, as applicable, that are not subject to the Collaboration and that are at an equivalent stage of development or commercialization and have similar market potential and are at a similar stage in their lifecycle, and (b) with respect to activities of ELAN in the Research Program, the Development of a particular Clinical Candidate or the Commercialization of a particular Product, the efforts and resources comparable to those undertaken by ELAN in pursuing intellectual property protection and development of product candidates and commercialization of products, as applicable, that are not subject to the Collaboration and that are at an equivalent stage of development or commercialization and have similar market potential and are at a similar stage in their lifecycle. For purposes of both (a) and (b) above, all relevant factors as measured by the facts and circumstances at the time such efforts are due shall be taken into account, including, as applicable D and without limitation, mechanism of action; efficacy and safety; product profile; actual or anticipated Regulatory Authority approved labeling; the nature and extent of market exclusivity (including patent coverage, proprietary position and regulatory exclusivity; cost, time required for and likelihood of obtaining Commercialization Regulatory Approval; competitiveness of CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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alternative products and market conditions; actual or projected profitability and availability of capacity to manufacture and supply for commercial sale).      1.39 " Commercialization Regulatory Approval " means, with respect to any Product, the Regulatory Approval required by Applicable Laws to sell such Product in a country or region. "Commercialization Regulatory Approval" shall include, without limitation, the approval of any Drug Approval Application. For purposes of clarity, "Commercialization Regulatory Approval" in the United States shall mean final approval of an NDA for a first Indication or sNDA for a second or later Indication permitting marketing of the applicable Product in interstate commerce in the United States. "Commercialization Regulatory Approval" in the European Union shall mean marketing authorization for the applicable Product pursuant to Council Directive 2001/83/EC, as amended, or Council Regulation 2309/93/EEC, as amended; and "Commercialization Regulatory Approval" in Japan shall mean final approval of an application submitted to the Ministry of Health, Labor and Welfare and the publication of a New Drug Approval Information Package permitting marketing of the applicable Product in Japan, as any of the foregoing may be amended from time to time.      1.40 " Competitive Entity " means any Third Party in the top [***] ([***]) companies ranked by [***] in the most recently completed Calendar Year for which such ranking is readily available from an unaffiliated Third Party.      1.41 " Competitive Program " means any research, development or commercialization activity that involves an aptamer that targets a Program Target.      1.42 " Confidential Information " means (a) with respect to ARCHEMIX, all embodiments of ARCHEMIX Technology and ARCHEMIX shall be deemed the "disclosing party" and ELAN the "receiving party" with respect thereto; (b) with respect to ELAN, all embodiments of ELAN Technology and/or ELAN Product Technology and ELAN shall be deemed the "disclosing party" and ARCHEMIX the "receiving party" with respect thereto; and (c) with respect to each Party, each of which shall be deemed both the "disclosing party" and "receiving party" with respect thereto, (i) all embodiments of Joint Technology, (ii) all information, Technology and Proprietary Materials, to the extent not described in (a) or (b), disclosed or provided by or on behalf of such Party (the "disclosing Party") to the other Party (the CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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"receiving Party") or to any of the receiving party’s employees, consultants, Affiliates or Sublicensees, (iii) the terms of this Agreement and (iv) all Technology generated hereunder in connection with the Research Program, the Development (including the Co-Development) of Clinical Candidates, and the Commercialization of Products; provided that none of the foregoing shall be Confidential Information if: (A) as of the date of disclosure, it is known to the receiving Party or its Affiliates, as demonstrated by credible written documentation, other than by virtue of a prior confidential disclosure by or on behalf of the other Party; (B) as of the date of disclosure it is in the public domain, or it subsequently enters the public domain through no unauthorized disclosure and no fault of the receiving Party; (C) it is obtained by the receiving Party from a Third Party having a lawful right to make such disclosure free from any obligation of confidentiality to the other Party; or (D) it is independently developed by or for the receiving Party without benefit from, reference to or use of any Confidential Information of the other Party as demonstrated by credible written documentation. For purposes of clarity, unless excluded from Confidential Information pursuant to the proviso at the end of the preceding sentence or otherwise allocated to one or both of the Parties pursuant to (a), (b) or (c) above, (1) any scientific, technical or financial information Controlled, as between the Parties, solely by one Party and disclosed at any meeting of the JMC or JPT, or disclosed through an audit or other report under this Agreement, shall constitute Confidential Information of the Controlling Party, and (2) any data, documentation or other information regarding an Amyloid Beta Agreement disclosed by or on behalf of ARCHEMIX pursuant to Section 4.10.2 shall constitute Confidential Information of ARCHEMIX.      1.43 " Contract Year " means (a) the period beginning on the Effective Date and ending on the first anniversary of the last day of the calendar month in which the Effective Date falls and (b) each succeeding twelve (12) month period thereafter.      1.44 " Control " or " Controlled " means (a) with respect to Technology or Patent Rights, the possession by a Party of the right to grant a license or sublicense to such Technology or Patent Rights as provided herein without the payment of additional consideration to, and without violating the terms of any agreement or arrangement with, any Third Party and without violating any Applicable Laws and (b) with respect to Proprietary Materials, the possession by a CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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Party of the right to supply such Proprietary Materials to the other Party as provided herein without the payment of additional consideration to, and without violating the terms of any agreement or arrangement with, any Third Party and without violating any Applicable Laws.      1.45 " Derived " means identified, obtained, developed, created, synthesized, generated, designed or resulting from; based upon; containing or incorporating; conjugated to or complexed with (whether directly or indirectly, or in whole or in part).      1.46 " Development " or " Develop " means all pre-clinical and clinical activities performed to obtain Regulatory Approval of a product up to and including the obtaining of Commercialization Regulatory Approval of such product. For purposes of clarity, these activities include, without limitation, test method development and stability testing, regulatory toxicology studies, formulation, process development, manufacturing, manufacturing scale-up, development-stage manufacturing, quality assurance/quality control development, statistical analysis and report writing, clinical trial design and operations, preparing and filing Drug Approval Applications, and all regulatory affairs related to the foregoing. When used as a verb, "Developing" means to engage in Development and "Developed" has a corresponding meaning.      1.47 " Development Costs " means the reasonable out-of-pocket costs and internal costs incurred by a Party (or for its account by an Affiliate or a Third Party) consistent with the respective Development activities of such Party as set forth in the Annual Development Plan or as mutually agreed by the Parties, and specifically attributable to Development or Co-Development of a Development Lead, Clinical Candidate or Product. For purposes of this definition (a) out-of-pocket costs means the actual amounts paid to a Third Party for specific external Development or Co-Development activities applicable to a Development Lead, Clinical Candidate or Product, including, without limitation, Manufacturing Costs and all filing fees required for and other costs associated with, any Regulatory Filings; (b) internal costs means the applicable FTE Rate multiplied by the number of FTE hours utilized in the relevant period on activities directly relating to the Development or Co-Development of a Development Lead, Clinical Candidate or Product in accordance with the Annual Development Plan or as mutually agreed by the Parties; and (c) the reasonable out-of-pocket and internal costs of obtaining Development Leads, Clinical Candidates or Products for use in the activities in clause (a), including without limitation internal CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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Manufacturing Costs. For the avoidance of doubt, Development Costs shall include the costs incurred by either Party in conducting clinical trials with respect to a Development Lead, Clinical Candidate or Product.      1.48 " Development Lead " means [***] (a) [***] the [***]and (b) [***] in [***] by [***] for the [***] of [***].      1.49 " Development Program " means, with respect to each Clinical Candidate, the Development activities to be conducted during the Term with respect to such Development Lead or Clinical Candidate pursuant to the Annual Development Plan, with the objective of developing such Development Lead or Clinical Candidate into a Product.      1.50 " Diagnosis " means (a) the determination or monitoring of (i) the presence or absence of a disease, (ii) the stage, progression or severity of a disease or (iii) the effect on a disease of a particular treatment; and/or (b) the selection of patients for a particular treatment with respect to a disease. For purposes of clarity, the term Diagnosis shall not include the delay of onset or progression of, or treatment or prevention of, an Indication.      1.51 " Diagnostic Product " means In Vitro Diagnostics, In Vivo Diagnostic Agents and any product used for Diagnosis.      1.52 " Diligence Indication " means (i) for IL-23 Aptamers, each of Crohn’s Disease, multiple sclerosis, psoriasis and rheumatoid arthritis, and (ii) for Collaboration Compounds other than IL-23 Aptamers, any single Indication.      1.53 " Drug Approval Application " means, with respect to a Product in a particular country or region, an application for Commercialization Regulatory Approval for such Product in such country or region, including without limitation: (a) an NDA or sNDA; (b) a counterpart of an NDA or sNDA in any country or region in the Territory; and (c) all supplements and amendments to any of the foregoing.      1.54 " Early Stage Development Costs " means, with respect to a Co-Developed Product, all Development Costs incurred by ELAN with respect to such Co-Developed Product during the period commencing on the date of designation by ELAN of the Development Lead or Clinical Candidate from which such Co-Developed Product was Derived, or constituting such Co- CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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Developed Product, and continuing up to the date that the Parties begin Co-Developing that Co-Developed Product.      1.55 " ELAN Background Technology " means any Technology that is used by ELAN, or provided by ELAN for use, or that is otherwise necessary or useful in the performance of the Research Program, the Development or Co-Development of Lead Compounds or Clinical Candidates and/or the Commercialization of Products that is (a) Controlled by ELAN as of the Effective Date or (b) Made by employees of, or consultants to, ELAN after the Effective Date other than in the conduct of ELAN Research Activities or ELAN Development Activities and without the use in a material respect of any ARCHEMIX Technology, ARCHEMIX Patent Rights, ARCHEMIX Materials or Program Technology. For purposes of clarity, ELAN Background Technology (a) shall not include, and shall not be included in, ELAN Program Technology, ELAN Product Technology or ELAN’s interest in Joint Technology.      1.56 " ELAN Decision " means any decision with respect to the following issues: (a) subject to Section 3.5.1(b), the replacement of any Program Target with another Target; (b) the nomination of an IL-23 Aptamer or a Collaboration Compound as a Lead Compound; (c) the nomination of a Lead Compound as a Clinical Candidate; (d) the [***] of [***] to be [***] in [***] to the [***]; (e) the use or application by ELAN of [***] and/or [***] and [***] in the conduct of the Research Program and/or the Development of Clinical Candidates; and (f) whether ELAN should [***] obtain a license to a Blocking Third Party Patent or any other Third Party Patent Rights.      1.57 " ELAN Development Activities " means all Development activities specified to be conducted by ELAN in any Annual Development Plan (or amendment thereto).      1.58 " ELAN Materials " means any Proprietary Materials that are Controlled by ELAN and used by ELAN, or provided by ELAN for use, in the Research Program, the Development Program and/or any other activities conducted hereunder, and that are not Joint Technology or Program Technology.      1.59 " ELAN Patent Rights " means any Patent Rights Controlled by ELAN that contain one or more claims that cover ELAN Technology. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     1.60 " ELAN Product Patent Rights " means any Patent Rights that contain one or more claims that cover ELAN Product Technology.      1.61 " ELAN Product Technology " means any Technology that is Made by employees of, or consultants to, ELAN, alone or jointly with any other entity (including ARCHEMIX) in the course of Development (but not Co-Development) of Development Leads and Clinical Candidates and/or Commercialization of Products other than Co-Developed Products; provided however, that any Technology that relates to the conduct of the SELEX™ Process or the use of the SELEX™ Technology shall not be considered to be ELAN Product Technology. For purposes of clarity, ELAN Product Technology shall not be included in Joint Technology.      1.62 " ELAN Program Technology " means any Program Technology that (a) is not ELAN Product Technology or Joint Technology; (b) is Made by or through employees of, or consultants to, ELAN, alone or with any Third Party; and (c) does not use in a material respect or benefit in a material respect from any ARCHEMIX Technology, ARCHEMIX Materials, ARCHEMIX Patent Rights or Joint Technology.      1.63 " ELAN Research Activities " means (a) all activities specified to be conducted by ELAN in any Annual Research Plan (or amendment thereto) that are (i) approved by the JMC and (ii) to the extent involving matters that are ELAN Decisions, approved by ELAN in accordance with Section 2.1.5, and (b) all research activities conducted by ELAN with respect to any Development Leads, Lead Compounds and Clinical Candidates undergoing Development and Products undergoing Commercialization.      1.64 " ELAN Technology " means, collectively, ELAN Background Technology and ELAN Program Technology.      1.65 " Enriched Pool " means a pool of oligonucleotides used to perform the SELEX™ Process against a Program Target in the performance of the Research Program that (a) has undergone [***] or more [***] of [***] and (b) wherein, using an [***] with [***] of [***] (i.e., [***] and [***] of the applicable Program Target, at least [***]% of the input pool of [***] is [***] in the assay by the Program Target and the [***] fraction of the [***] pool is at least [***] to the [***] fraction for [***] (i.e., [***]) pool of [***]. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     1.66 " Effective Date " means the date first set forth above.      1.67 " Excepted Decision " means any of the following decisions requiring the unanimous approval of all members of the JMC: (a) any decision as to whether a milestone has been achieved under this Agreement for which a milestone payment is payable; (b) any Significant Co-Development Decision made [***] Phase III Clinical Trials with respect to the Co-Development of a [***] in a [***]; and (c) any disagreement between the Parties on the appropriate method of determining royalties for a Combination Product in accordance with Section 5.4.1(f).      1.68 " Excluded Aptamer " means any Aptamer listed on Schedule 5 .      1.69 " Excluded Target " means any Target listed on Schedule 2 .      1.70 " Failed Target " means any Program Target or proposed Program Target as to which the JPT concludes and the JMC agrees that, after using Commercially Reasonable Efforts to identify Aptamers, or based on prior activities of ARCHEMIX, [***] is unable or unlikely to identify [***] against such Program Target.      1.71 " FDA " means the United States Food and Drug Administration or any successor agency or authority thereto.      1.72 " FDCA " means the United States Federal Food, Drug, and Cosmetic Act, as amended.      1.73 " First Commercial Sale " means, with respect to a Product in a country in the Territory, the first sale, transfer or disposition for value to an end-user of such Product in such country.      1.74 " Force Majeure " means any occurrence beyond the reasonable control of a Party that (a) prevents or substantially interferes with the performance by such Party of any of its obligations hereunder and (b) occurs by reason of any act of God, flood, fire, explosion, earthquake, strike, lockout, labor dispute, casualty or accident, or war, revolution, civil commotion, act of terrorism, blockage or embargo, or any injunction, law, order, proclamation, CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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regulation, ordinance, demand or requirement of any government or of any subdivision, authority or representative of any such government, to the extent and for the duration of such occurrence.      1.75 " FTE " shall mean [***] hours of work devoted to or in support of the ARCHEMIX Research Activities or the ARCHEMIX Development Activities that is carried out by one or more employees, contract personnel or consultants of ARCHEMIX, measured in accordance with ARCHEMIX’ time allocation practices from time to time.      1.76 " FTE Cost " means, for any period, the FTE Rate multiplied by the applicable number of FTEs in such period.      1.77 " FTE Rate " means [***] Dollars (US $[***]); provided that on January 1 of each Calendar Year in the Term, commencing with January 1, 2007, the FTE Rate will be [***] by multiplying the FTE Rate applicable on December 31 of the immediately preceding Calendar Year by [***], where [***] is the Consumer Price Index for All Urban Consumers in the Boston Metropolitan Area published by the Bureau of Labor Statistics of the United States Department of Labor for [***] in the immediately preceding [***] and [***] is the Consumer Price Index for All Urban Consumers in the Boston Metropolitan Area published by the Bureau of Labor Statistics of the United States Department of Labor (i) for the [***] the Effective Date for the period commencing on the Effective Date and continuing until the [***] of the [***] ended [***] and (ii) for each [***] thereafter, for the [***] in the immediately preceding [***] (e.g. in [***] is [***] as at [***] and [***] is [***] as at [***]). Any such [***] shall be rounded to the nearest [***] US Dollars ($[***]).      1.78 " Fully-Exercised Co-Developed Product " means any Co-Developed Product with respect to which the ARCHEMIX Co-Development Percentage is [***] percent ([***]%).      1.79 " GAAP " means United States generally accepted accounting principles, consistently applied.      1.80 " Hatch-Waxman Act " means the Drug Price Competition and Patent Term Restoration Act of 1984, as amended.      1.81 " HSR Act " means the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     1.82 " IL-23 " means the Program Target designated and defined as IL-23 on Schedule 1 attached hereto.      1.83 " IL-23 Aptamer " means (a) any Program Aptamer that binds IL-23 that is identified by performing the SELEX™ Process against IL-23 in the conduct of the Research Program or any Aptamer Derived therefrom that binds IL-23, and/or (b) any Aptamer that binds IL-23 that is covered by one or more of the claims of the IL-23 Patent Applications or any Aptamer that binds IL-23 Derived therefrom. For purposes of clarity, IL-23 Aptamers include, without limitation, ARC2350 and all IL-23 Back-Up Compounds.      1.84 " IL-23 Back_Up Compounds " means all IL-23 Aptamers other than ARC2350.      1.85 " IL-23 Patent Applications " means (a) the following patent applications: (i) United States Patent Application Serial No. 11/075649; (ii) PCT Patent Application Serial No. US2005/007666; and (iii) United States Patent Application Serial No. 11/234676 and (b) all applications, substitutions, continuations, continuations-in-part, divisions, renewals, all letters patent granted thereon, and all reissues, re-examinations and extensions thereof, and all foreign counterparts of any of the foregoing.      1.86 " IL-23 Product " means any pharmaceutical or medicinal item, substance or formulation that contains, incorporates or comprises an IL-23 Aptamer or an Aptamer Derived therefrom that binds specifically to IL-23.      1.87 " IND " means: (a) an Investigational New Drug Application as defined in the FDCA and regulations promulgated thereunder or any successor application or procedure required to initiate clinical testing of a Clinical Candidate in humans in the United States; (b) a counterpart of an Investigational New Drug Application that is required in any other country or region in the Territory before beginning clinical testing of a Clinical Candidate in humans in such country or region; and (c) all supplements and amendments to any of the foregoing.      1.88 "IND Acceptance " means, with respect to an IND, the earlier of the receipt of notification of acceptance of such IND from the FDA or the expiration of thirty (30) days from the date of filing of such IND with the FDA. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     1.89 " Indication " means any human disease or condition which can be treated, prevented, cured or the onset or progression of which can be delayed and which would require the filing of a separate NDA or sNDA to obtain Commercialization Regulatory Approval for such disease or condition.      1.90 " Initiation " means, with respect to a human clinical trial, the first date that a subject or patient is dosed in such clinical trial.      1.91 " In Vitro Diagnostics " means the use of the SELEX™ Process or Aptamers or PhotoAptamers identified through the use of the SELEX™ Process in the assay, testing or determination, outside of a living organism, of a substance in a test material. In Vitro Diagnostics shall include, among other things, the use of the SELEX™ Process or Aptamers or PhotoAptamers identified through the use of the SELEX™ Process in the assay, testing or determination: (a) outside of a living organism, (i) of a human substance in a test material, often to identify or follow the progression of a disease or disorder, or to select a patient for treatment; (ii) of a plant substance, animal substance or other substance in a test material, often to identify or follow the progression of a disease, process, or disorder in a human or non-human organism; and (iii) of environmental substances (as in water quality testing); and (b) of a substance on a test material such as cells (as in FACS analysis or other measurements of pathogens within biological samples).      1.92 " In Vivo Diagnostic Agent " means any product containing one or more Aptamers that is used for any human in vivo diagnostic purpose related to ( inter alia ) the identification, quantification or monitoring of the propensity toward, or actual existence of, any disease state.      1.93 " Joint Management Committee " or " JMC " means the committee composed of ARCHEMIX and ELAN representatives established pursuant to Section 2.1.      1.94 " Joint Patent Rights " means Patent Rights that contain one or more claims that cover Joint Technology.      1.95 " Joint Project Team " or " JPT " means the committee composed of ARCHEMIX and ELAN representatives established pursuant to Section 2.2. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     1.96 " Joint Technology " means (a) any Program Technology that is (i) jointly Made by employees of, or consultants to, ELAN and employees of, or consultants to, ARCHEMIX in the performance of the Research Program, or (ii) Made solely by employees of, or consultants to, either Party with the use in a material respect of any Technology, Patent Rights or Proprietary Materials Controlled by the other Party or any other Joint Technology; (b) any Program Aptamer; (c) any Patented Aptamer; and (d) any Program Technology that relates to Pegylation. For purposes of clarity, (i) any Program Technology that relates to the conduct of the SELEX™ Process or the use of the SELEX™ Technology shall not be considered to be Joint Technology, and (ii) Joint Technology shall not include any IL-23 Aptamers Made by ARCHEMIX as of the Effective Date, and any Product Derived from any such IL-23 Aptamers without the use in a material respect of any Technology, Patent Rights or Proprietary Materials Controlled by ELAN.      1.97 " Knowledge " means, with respect to a Party, the actual knowledge of the chief executive officer or any vice president of such Party.      1.98 " Lead Selection Criteria " or " LSC " means the guideline criteria for selecting Collaboration Compounds or IL-23 Aptamers that are sufficiently promising to warrant further research as a Lead Compound, such criteria to be set forth in the Annual Research Plan with respect to the Program Targets listed on Schedule 1 as of the Effective Date and/or to any other Program Target to be included in the Research Program before any activities with respect to such Program Target are initiated in the Research Program. For purposes of clarity, the LSC for a Program Target shall include, at a minimum, binding affinity, specificity, activity and size criteria but shall not include animal efficacy, animal toxicology, process development or cost of goods criteria.      1.99 " Licensed Patent Rights " means any ARCHEMIX Patent Rights and ARCHEMIX’ interest in Joint Patent Rights that (a) contain one or more claims that cover any Collaboration Aptamer, including its manufacture or its formulation or a method of its delivery or of its use, or (b) claim inventions that are necessary for ELAN to exercise the licenses granted to it pursuant to Sections 7.1.1 and 7.2.1 under the Licensed Patent Rights described in subsection (a). For purposes of clarity, (a) the Licensed Patent Rights shall exclude any Patent Rights that relate to the conduct of the SELEX™ Process and/or the use of the SELEX™ Technology; (b) the CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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Licensed Patent Rights as of the Effective Date include without limitation the Patent Rights listed on Schedule 3 attached hereto; and (c) ARCHEMIX shall update Schedule 3 not less than annually during the Term to add any additional Patent Rights that become Licensed Patent Rights.      1.100 " Licensed Technology " means any ARCHEMIX Technology and ARCHEMIX’ interest in Joint Technology that (a) relates to any Collaboration Aptamer, including its manufacture or its formulation or a method of its delivery or of its use or (b) is necessary for ELAN to exercise the licenses granted to it pursuant to Section 7.1.1 and 7.2.1 under the Licensed Technology described in subsection (a).      1.101 " Made " means (a) with respect to patentable Technology, discovered, conceived or first reduced to practice, whether actively or constructively, and (b) with respect to all other Technology, first generated, identified, synthesized or developed.      1.102 " Major Market Country " means [***] of the [***] and [***]For [***] of [***] the[***] and [***]      1.103 " NDA " means a New Drug Application, as defined in the FDCA and regulations promulgated thereunder or any successor application or procedure required to sell a Product in the United States.      1.104 " Net Sales " means the gross amount billed or invoiced by ELAN or any of its Affiliates or Sublicensees to Third Parties throughout the Territory for sales or other dispositions or transfers for value of Products less (i) allowances for normal and customary trade (including those granted in core distribution agreements and inventory management agreements), quantity and cash discounts actually allowed and taken, (ii) transportation, insurance and postage charges, if paid by ELAN or any Affiliate or Sublicensee of ELAN and included on any such entity’s bill or invoice as a separate item, (iii) credits, chargebacks, rebates, returns pursuant to agreements (including, without limitation, managed care agreements) or government regulations, to the extent actually allowed, and (iv) any tax, tariff, customs duty, excise or other duty or other governmental charge (other than a tax on income) levied on the sale, transportation or delivery of Product and actually paid by ELAN, or any of its Affiliates or Sublicensees. In addition, Net Sales are subject to the following: CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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          (a) If ELAN or any of its Affiliates or Sublicensees effects a sale, disposition or transfer of a Product to a customer in a particular country other than on customary commercial terms or as part of a package of products and services (but not in a Combination Product), the Net Sales of such Product to such customer shall be deemed to be "the fair market value" of such Product. For purposes of this subsection (a), "fair market value" shall mean the value that would have been derived had such Product been sold as a separate product to another customer in the country concerned on customary commercial terms.           (b) In the case of pharmacy incentive programs, hospital performance incentive program chargebacks, disease management programs, similar programs or discounts on "bundles" of products, all discounts and the like shall be allocated among products on the basis on which such discounts and the like were actually granted or, if such basis cannot be determined, in proportion to the respective list prices of such products.           (c) For purposes of clarity, use of any Product in clinical trials, pre-clinical studies or other research or development activities, or disposal or transfer of Products for a bona fide charitable purpose or purposes of a commercially reasonable sampling program shall not give rise to any Net Sales.      1.105 " Non-Parenteral " means all methods of administering a therapeutic substance or medication to a patient that do not involve puncture of the skin or any active delivery through the skin through the use of a device.      1.106 " Non-Parenteral Co-Development Option " means any Co-Development Option for an IL-23 Product intended to treat any Indication in a Non-Parenteral formulation.      1.107 " Non-Parenteral Co-Developed Product " means any (a) IL-23 Product or (b) IL-23 Aptamer in Development as a Development Lead or a Clinical Candidate, in either case that is intended to treat any Indication in a Non-Parenteral formulation and as to which ARCHEMIX has exercised the Non-Parenteral Co-Development Option.      1.108 " Non-Parenteral Option Termination Date " means, with respect to each potential IL-23 Product Developed to treat any Indication in a Non-Parenteral formulation, the CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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date estimated in good faith by ELAN to be [***] days before the date of Initiation of the initial Phase II Clinical Trial with respect to such potential IL-23 Product.      1.109 " Operating Income (Loss) " has the meaning set forth on Schedule 4 attached hereto.      1.110 " Option Termination Date " means a Psoriatic Diseases Option Termination Date or a Non-Parenteral Option Termination Date.      1.111 " Patent Rights " means issued patents and pending patent applications (which, for purposes of this Agreement, include certificates of invention, applications for certificates of invention and priority rights) in any country or region, including all provisional applications, substitutions, continuations, continuations-in-part, divisions, renewals, all letters patent granted thereon, and all reissues, re-examinations and extensions thereof, and all foreign counterparts of any of the foregoing.      1.112 " Patented Aptamer " means any Aptamer claimed in or covered by Program Aptamer-Specific Patent Rights.      1.113 " Pegylation " means Technology relating to the covalent or non-covalent linking of any polyalkylene oxide and/or polyalkylene ether moiety (including but not limited to polyethylene glycol and polypropylene glycol) to another compound, such as an Aptamer.      1.114 " Permitted Screening Activities " means, [***] to any [***]any [***] ARCHEMIX [***] to such [***] for [***] for [***] for the [***] of [***] Aptamers [***] to a [***] a [***]; provided, however, [***] of a [***] as a [***] be a [***] if and only if (a) [***] with [***] (i.e., [***] into a [***] ARCHEMIX [***] of any [***] or [***] as [***] under this [***] or if ARCHEMIX [***] ARCHEMIX [***] under this [***] or (b) [***] is no [***], ARCHEMIX [***] ELAN, [***] or [***] in the [***] ELAN, [***] as a[***] for such [***]      1.115 " Person " means an individual, sole proprietorship, partnership, limited partnership, limited liability partnership, corporation, limited liability company, business trust, joint stock company, trust, incorporated association, joint venture or similar entity or organization, including a government or political subdivision, department or agency of a government. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     1.116 " Phase I Clinical Trial " means a clinical trial conducted in accordance with a protocol approved by the JMC, in healthy humans or patients, which clinical trial is designed to establish the safety, drug-drug interactions and/or pharmacokinetics of an investigational drug given its intended use, and to support continued testing of such drug in Phase II Clinical Trials.      1.117 " Phase II Clinical Trial " means a clinical trial conducted in patients with a particular disease or condition in accordance with a protocol approved by the JMC, which clinical trial is designed to establish the safety, appropriate dosage and pharmacological activity of an investigational drug given its intended use, and to initially explore its efficacy for such disease or condition.      1.118 " Phase III Clinical Trial " means a pivotal clinical trial conducted in patients with a particular disease or condition in accordance with a protocol approved by the JMC, which clinical trial is designed to ascertain efficacy and safety of an investigational drug for its intended use and to define warnings, precautions and Adverse Events that are associated with the Clinical Candidate in the dosage range intended to be prescribed, with the purpose of preparing and submitting applications for Regulatory Approval or label expansion to the pertinent Regulatory Authority in any country.      1.119 " Product " means any IL-23 Product and/or any Collaboration Product.      1.120 " Product Commercialization Plan " means, with respect to each Product, the written plan for the Commercialization of such Product in the Territory (including, without limitation, expected manufacturing scale-up, manufacture, formulation and filling requirements for such Product and a detailed strategy, budget and proposed timelines), as such plan may be amended or updated.      1.121 " Product Trademarks " means any trademark or trade name, whether or not registered, or any trademark application or renewal, extension or modification thereof, in the Territory, or any trade dress and packaging, in each case (a) that are applied to or used with any Product by ELAN and (b) together with all goodwill associated therewith and promotional materials relating thereto. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     1.122 " Program Aptamer " means any Program Oligonucleotide that is an Aptamer that binds a Program Target and that is identified in the performance of the Research Program or during Development and/or any Aptamer that binds a Program Target that is Derived from such Program Oligonucleotide, regardless of its stage of research or Development, including, without limitation, Lead Compounds and Clinical Candidates.      1.123 " Program Aptamer-Specific Patent Rights " means all Patent Rights that cover only Program Aptamer-Specific Technology.      1.124 " Program Aptamer-Specific Technology " means any Program Technology that relates specifically and solely to (i) any Program Aptamer, IL-23 Aptamer or Product or (ii) the manufacture, formulation, delivery or use of a Program Aptamer, IL-23 Aptamer or Product.      1.125 " Program Oligonucleotide " means the [***] and [***] obtained from an [***] and [***] and [***] in the performance of [***] against a [***] that is not a [***].      1.126 " Program Technology " means any Technology (including, without limitation, any new and useful process, method of manufacture or composition of matter) or Proprietary Materials that are Made by either Party in the conduct of the Research Program or the Co-Development of Clinical Candidates and/or Co-Developed Products. For the avoidance of doubt, Program Technology does not include, and is not included in, ELAN Background Technology, ARCHEMIX Background Technology or ELAN Product Technology.      1.127 " Program Target " means the Targets listed on Schedule 1 , as amended from time to time in accordance with Section 3.5; provided, however, that there shall be no more than four (4) Targets listed on Schedule 1 at any point in time, and each of these shall be a Target that ELAN reasonably believes based on publicly available literature or proprietary data has activity in the Target Selection Field. For purposes of clarity, the term Program Target shall include as the Target against which the SELEX™ Process may be performed (a) in the case of a ligand, (i) the designated ligand and the designated components or subunits [***] and (ii) [***] to which [***] and the [***] or [***] of such [***]but [***] any other [***] or other [***] that [***] with such [***] or [***] or such [***] or [***]; (b) [***] of a [***], (i) the [***] and the [***] or [***] of such [***], and (ii) a [***] to which [***] and the [***] or [***] of such [***] but [***] any CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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other [***] or other [***] that [***] a [***] with such [***] or [***] or such [***] or[***]; (c) [***] of a [***] or [***] of a [***], (i) the [***], and (ii) a [***] to which [***] and the [***]or [***] of such [***] but [***] any other [***] or other [***]that [***] a [***] with such [***] or [***] or such [***] or [***]; and (d) [***] of a [***] or [***] of a [***], (i) the [***] or [***], and (ii) a [***] to which [***] and the [***] or [***] of such [***]but [***] any other [***] or other[***] that [***] a [***] with such [***] or [***] or such [***] or [***]. By way of example, the [***] (i) the [***] and [***] and (ii) the [***] and [***].      1.128 " Proprietary Materials " means tangible chemical, biological or physical materials (a) that are furnished by or on behalf of one Party to the other Party in connection with this Agreement, whether or not specifically designated as proprietary by the transferring Party or (b) that are otherwise first Made by a Party in the conduct of the Research Program or the Development Program.      1.129 " Psoriatic Diseases " means psoriatic diseases, including without limitation psoriasis and psoriatic arthritis.      1.130 " Psoriatic Diseases Co-Development Option " means any Co-Development Option for a parenteral formulation of an IL-23 Product intended to treat Psoriatic Diseases.      1.131 " Psoriatic Diseases Co-Developed Product " means any (a) parenteral IL-23 Product or (b) IL-23 Aptamer in Development as a Development Lead or Clinical Candidate in a parenteral formulation, in either case that is intended to treat Psoriatic Diseases and as to which ARCHEMIX has exercised the Psoriatic Diseases Co-Development Option.      1.132 " Psoriatic Diseases Option Termination Date " means, with respect to each parenteral formulation of a potential IL-23 Product Developed for the treatment of Psoriatic Diseases, the date estimated in good faith by ELAN to be [***] ([***]) days before the date of Initiation of the initial Phase II Clinical Trial with respect to that potential IL-23 Product.      1.133 " Quarter " means the stub period beginning on the Effective Date and ending on the last day of the calendar quarter in which the Effective Date falls, and thereafter each successive period of three (3) consecutive calendar months ending on March 31, June 30, September 30 or December 31. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     1.134 " Radio Therapeutic " means any product for human therapeutic use that contains one or more Aptamers that targets specifically any diseased tissue, cells or disease-specific molecules or any tissue or cells which are affected by a disease or located in the close neighborhood of a disease process and is linked to or incorporates (a) radionucleotides or (b) any structure or elements which develop therapeutic effects similar to the effect of linking or incorporating radionucleotides after submission of any kind of radiation.      1.135 " Regulatory Approval " means, with respect to any country or region in the Territory, any approval or license of any Regulatory Authority required for the manufacture, use, storage, importation, exportation, transport, sale or other distribution of a Product for use in such country or region.      1.136 " Regulatory Authority " means the FDA, or any counterpart of the FDA outside the United States, or any other national, supra-national, regional, state or local regulatory agency, department, bureau, commission, council or other governmental entity with authority over the distribution, importation, exportation, manufacture, production, use, storage, transport, clinical testing or sale of a Product.      1.137 " Regulatory Filings " means, collectively: (a) all INDs, license applications, drug master files, applications for designation as an "Orphan Product(s)" under the Orphan Drug Act, for "Fast Track" status under Section 506 of the FDCA (21 U.S.C. § 356) or for a Special Protocol Assessment under Section 505(b)(4)(B) and (C) of the FDCA (21 U.S.C. § 355(b)(4)(B)), NDAs, BLAs and all other similar filings (including, without limitation, counterparts of any of the foregoing in any country or region in the Territory); (b) all supplements and amendments to any of the foregoing; and (c) all data and other information contained in, and correspondence relating to, any of the foregoing.      1.138 " Rejected Program Target " means any Program Target that is rejected by written notice from ELAN pursuant to Section 3.5.1(a).      1.139 " Research Program " means the research program to be conducted by the Parties during the Research Program Term pursuant to the Annual Research Plan, including but not limited to the identification and initial testing of Collaboration Compounds and IL-23 Aptamers, CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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the selection of Lead Compounds from Collaboration Compounds and IL-23 Aptamers and the selection of Clinical Candidates from such Lead Compounds for further Development. For purposes of clarity, the Research Program does not include any Development activities performed in the course of the Development Program.      1.140 " Research Program Term " means, subject to Section 13.2.1(b), the period beginning on the Effective Date and ending on the last day of the third Contract Year or such later date as the Parties may mutually agree in writing; provided, that, if this Agreement is terminated prior to the end of the Research Program Term, the effective date of such early termination specified in the termination notice shall become the last day of the Research Program Term.      1.141 " Royalty-Bearing Product " means (a) any Product that is not a Co-Developed Product, (b) any Product contained in a Combination Product that is not a Co-Developed Product and (c) any Co-Developed Product to the extent sold outside of a Co-Development Territory or for an Indication or in a formulation other than one for which Co-Development occurs.      1.142 " Royalty Term " means, with respect to each Royalty-Bearing Product in each country in the Territory, the period beginning on the date of First Commercial Sale of such Royalty-Bearing Product in such country and ending on the later to occur of (a) expiration of the last to expire Valid Claim of the Licensed Patent Rights or ELAN Joint Product Patent Rights in such country that covers such Royalty-Bearing Product or its identification, manufacture, use, import, offer for sale or sale or (b) [***] years from the date of the First Commercial Sale of such Royalty-Bearing Product in such country.      1.143 " ROW " means all countries and territories of the world other than the United States and its territories and possessions and the Major Market Countries.      1.144 " SELEXTM   Portfolio " means those Patent Rights licensed by Gilead to ARCHEMIX pursuant to the ARCHEMIX-Gilead License Agreement.      1.145 " SELEXTM   Process " means any process for the identification or generation of a nucleic acid that binds to a Target by means other than Watson-Crick base-pairing, including without limitation any such process that (a) is covered by, or is described in, the SELEX™ Portfolio, including without limitation U.S. Patent Nos. [***] or [***], (b) is covered by, or is CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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described in, any other Patent Rights Controlled by ARCHEMIX, and (c) any continuations, divisionals and continuations-in part substitutions, renewals, reissues, re-examinations and extensions of and improvements to the inventions covered by, or described in, the foregoing Patent Rights.      1.146 " SELEXTM   Technology " means any process for modifying, optimizing and/or stabilizing an aptamer wherein such modification, optimization or stabilization includes, without limitation minimization, truncation, conjugation other than Pegylation, complexation, substitution, deletion and/or incorporation of modified nucleotides.      1.147 " Serious Adverse Event " means an Adverse Event occurring at any dose of a drug that: results in death; poses an immediate risk of death; requires inpatient hospitalization; results in a persistent and/or significant disability, illness or incapacity; or results in a congenital anomaly or birth defect. An Adverse Event that does not fulfill the above criteria nonetheless may be considered a Serious Adverse Event when, based upon reasonable medical judgment, it may jeopardize the patient or subject and may require medical or surgical intervention to prevent one of the above outcomes.      1.148 " Significant Co-Development Decision " means (i) [***] that would [***] be [***] to [***] the [***] of [***] and/or [***] to be [***]ARCHEMIX[***] a [***] with [***] and (ii) [***] with [***] to the [***] and [***] of [***] to, the [***] of [***] for, and [***] and [***] with the [***], such [***] for the [***] and [***].      1.149 " sNDA " means a Supplemental New Drug Application, as defined in the FDCA and applicable regulations promulgated thereunder.      1.150 " Sublicense Agreement " means any agreement entered into by ELAN with a Sublicensee.      1.151 " Sublicensee " means any Third Party to which a Party grants a sublicense under the licenses granted to it under Section 7.1 or 7.2.      1.152 " Supplemental Product " means a product having independent, supplementary or enabling therapeutic effect (e.g., as a catalyst or adjuvant) or diagnostic utility or that has independent function as a medical device or means of administration. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     1.153 " Target " means a protein, cytokine, enzyme, receptor, transducer, transcription factor, antigen or any other non-nucleic acid molecule.      1.154 " Target Selection Field " means the treatment or prevention in humans of any autoimmune or inflammatory Indication.      1.155 " Technology " means, collectively, inventions, discoveries, improvements, trade secrets and proprietary methods, whether or not patentable, including without limitation: (a) methods of production or use of, and structural and functional information pertaining to, chemical compounds and (b) compositions of matter, data, formulations, processes, techniques, know-how and results (including without limitation any negative results).      1.156 " Terminated Program Aptamer " means (a) all Program Aptamers that bind specifically to any Rejected Program Target, (b) upon any termination of this Agreement by ARCHEMIX pursuant to Section 10.2.3 or the first sentence of Section 10.2.2 or by ELAN pursuant to Section 10.2.1, all Collaboration Aptamers, and (c) upon any termination of ELAN’s license by ARCHEMIX pursuant to the last sentence of Section 10.2.2, the relevant Collaboration Aptamers binding specifically to the Program Target for which such license is terminated due to failure to meet its diligence obligations, as provided in Section 10.3.4.      1.157 " Territory " means all countries and territories of the world.      1.158 " Third Party " means a Person other than ELAN and ARCHEMIX and their respective Affiliates.      1.159 " URC License Agreement " means the Restated Assignment and License Agreement, dated July 17, 1991, by and between University Research Corporation and Gilead as successor in interest to NeXstar.      1.160 " UTC " means University Technology Corporation, the successor to the University Research Corporation.      1.161 " Valid Claim " means any claim of a pending patent application which has been pending for a period of ten (10) years or less from its earliest priority filing date or an issued unexpired patent that (a) has not been finally cancelled, withdrawn, abandoned or rejected by any CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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administrative agency or other body of competent jurisdiction, (b) has not been permanently revoked, held invalid, or declared unpatentable or unenforceable in a decision of a court or other body of competent jurisdiction that is unappealable or unappealed within the time allowed for appeal, (c) has not been rendered unenforceable through disclaimer or otherwise, and (d) is not lost through an interference proceeding.       Additional Definitions . In addition, each of the following definitions shall have the respective meanings set forth in the section of this Agreement indicated below:

CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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2. ADMINISTRATION OF THE COLLABORATION      2.1 Joint Management Committee .           2.1.1   Establishment . ARCHEMIX and ELAN hereby establish the Joint Management Committee. The JMC shall have and perform the responsibilities set forth in Section 2.1.4.           2.1.2   Membership . Each Party shall designate, in its sole discretion, [***] members to the JMC, which shall be members of its, or its Affiliates’, management. Unless otherwise agreed by the Parties, one of ELAN’s designees shall be designated by ELAN as the Chair. Each Party shall have the right at any time to substitute individuals, on a permanent or temporary basis, for any of its previously designated representatives to the JMC, by giving written notice to the other Party. Initial designees of the Parties to the JMC shall be as follows:

CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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          2.1.3 Meetings.                (a)  Schedule of Meetings; Agenda . The JMC shall establish a schedule of times for regular meetings, taking into account the planning needs of the Collaboration and its responsibilities. Special meetings of the JMC may be convened by any member upon [***] days (or, if such meeting is proposed to be conducted by teleconference, upon [***] days) written notice to the other members; provided that (i) notice of any such special meeting may be waived at any time, either before or after such meeting, and such waiver shall be the equivalent to the giving of a valid notice hereunder, and (ii) attendance of any member at a special meeting shall constitute a valid waiver of notice from such member. In no event shall the JMC meet less frequently than once in each Calendar Year. Regular and special meetings of the JMC may be held in person or by teleconference or videoconference; provided that meetings held in person shall alternate between the respective offices of the Parties. The Chair shall prepare and circulate to each JMC member an agenda for each JMC meeting not later than [***] prior to such meeting.                (b)  Quorum; Voting; Decisions . At each JMC meeting (i) the presence in person of at least [***] members designated by each Party shall constitute a quorum. The JMC shall use reasonable efforts in good faith to resolve by unanimous consent any issue within its jurisdiction. Alternatively, the JMC may act by written consent signed by [***] member designated by each Party, subject to Section 2.1.5. Whenever any action by the JMC is called for hereunder during a time period in which the JMC is not scheduled to meet, the chair of the JMC shall cause the JMC to take the action in the requested time period by calling a special meeting or by circulating a draft written consent. If the JMC is unable to unanimously agree with respect to any issue, notwithstanding the exercise of reasonable efforts, [***] shall have the tie-breaking vote as stated in Section 2.1.5. Representatives of each Party or of its Affiliates who are not members of the JMC, and consultants who are subject to confidentiality obligations no less stringent than those contained herein, may attend JMC meetings as non-voting observers with the consent of the other Party, which shall not be unreasonably withheld, conditioned or delayed. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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               (c)  Minutes . The JMC shall keep minutes of its meetings that record all decisions and all actions recommended or taken in reasonable detail. Drafts of the minutes shall be prepared and circulated to the members of the JMC within a reasonable time after the meeting, not to exceed [***] business days. The chair of the JMC shall have responsibility for the preparation and circulation of draft minutes. Each member of the JMC shall have the opportunity to provide comments on the draft minutes. The minutes shall be approved, disapproved and revised as necessary at the next JMC meeting or within [***] days of the meeting, whichever occurs first. Upon approval, final minutes of each meeting shall be circulated to the members of the JMC by the chair of the JMC.                (d)  Expenses . ARCHEMIX and ELAN shall each bear all expenses of their respective JMC members related to their participation on the JMC and attendance at JMC meetings.           2.1.4 Responsibilities . The JMC shall be responsible for (a) overseeing the conduct and progress of the Research Program, and (b) providing a forum for the exchange of information between the Parties with respect to the Development of Program Aptamers, Lead Compounds and Clinical Candidates that are, or are eligible for designation as, Co-Developed Products and the Co-Development and Commercialization of Co-Developed Products in the applicable Co-Development Territory(ies), Indication and formulation; provided however, that the JMC shall not be responsible for overseeing the Development or Commercialization of any Products. Without limiting the generality of the foregoing, the JMC shall have the following responsibilities:                (a) overseeing the JPT’s performance of its responsibilities;                (b) reviewing each Annual Research Plan, each Annual Development Plan for Clinical Candidates eligible for designation as Co-Developed Products and for Co-Developed Products in the applicable Co-Development Territory(ies), Indication and formulation, and, only if ELAN alone (rather than with or through a Sublicensee) is Commercializing a Co-Developed Product, each Product Commercialization Plan for a Co-Developed Product in the applicable Co-Development Territory(ies), Indication and formulation (including all budgets applicable thereto); provided, that, ELAN agrees to use Commercially CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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Reasonable Efforts to include the JMC rights set forth in this Section 2.1.4(b) in each Sublicense Agreement;                (c) approving any Annual Research Plan;                (d) directing the preparation of, and reviewing each amendment to, any Annual Research Plan and/or budget applicable thereto;                (e) approving any amendment or update to an Annual Research Plan;                (f) reviewing data, reports or other information submitted to it by the JPT from time to time;                (g) discussing the progress of the Commercialization of each Co-Developed Product in the applicable Co-Development Territory(ies), Indication and formulation in accordance with the applicable Product Commercialization Plan, if ELAN alone (rather than with or through a Sublicensee) is marketing a Co-Developed Product; provided, that, ELAN agrees to use Commercially Reasonable Efforts to include the JMC rights set forth in this Section 2.1.4(g) in each Sublicense Agreement;                (h) resolving all JPT matters that are in dispute;                (i) reviewing any proposal of the JPT to nominate any Collaboration Compound or IL-23 Aptamer as a Lead Compound or any proposal of the JPT to nominate any Lead Compound as a Clinical Candidate; and                (j) making such other decisions as may be delegated to the JMC pursuant to this Agreement or by mutual written agreement of the Parties after the Effective Date.           2.1.5 Dispute Resolution . The JMC members shall use reasonable efforts to reach agreement on any and all matters. In the event that, despite such reasonable efforts, agreement on a particular matter cannot be reached by the JMC within [***] days after the JMC first meets to consider such matter (each such matter, a "Disputed Matter"), then, if the Disputed Matter involves an ELAN Decision or any matter other than an Excepted Decision or an ARCHEMIX Decision, and except as set forth in the last sentence of this section, ELAN shall CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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have the right to make the final decision on such Disputed Matter, but shall only exercise such right in good faith using its commercially reasonable discretion after consideration of the positions of both Parties. Notwithstanding the foregoing, (i) if the Disputed Matter involves an ARCHEMIX Decision, then ARCHEMIX shall have the right to make the final decision on such Disputed Matter but shall only exercise such right in good faith using its commercially reasonable discretion after consideration of the positions of both Parties, and (ii) if the Disputed Matter involves an Excepted Decision, the Chair of the JMC shall refer such Disputed Matter to the President of ARCHEMIX and the President (US) of ELAN (the "Designated Senior Officers"), who shall promptly initiate discussions in good faith to resolve such Disputed Matter. If the Disputed Matter is not resolved by the Designated Senior Officers within thirty (30) days after the date the Designated Senior Officers first met to consider such Disputed Matter or sixty (60) days after the date the JMC first met to consider such Disputed Matter, then subject to Section 13.1, either Party may seek any remedy, at law or in equity, that may be available. For purposes of clarity, under no circumstances shall the determination of whether ELAN or ARCHEMIX has used or is using Commercially Reasonable Efforts be submitted for resolution under this Section 2.1.5.      2.2 Joint Project Team .           2.2.1 Establishment . ARCHEMIX and ELAN hereby establish the Joint Project Team. The JPT shall have and perform the responsibilities set forth in Section 2.2.4.           2.2.2 Membership . Each Party shall designate, in its sole discretion, [***] members to the JPT (which members shall be employees or consultants of such Party or an Affiliate of such Party). Unless otherwise agreed by the Parties, one of ARCHEMIX’ designees shall be designated by ARCHEMIX as the chair of the JPT. Each Party shall have the right at any time to substitute individuals, on a permanent or temporary basis, for any of its previously designated representatives to the JPT, by giving written notice to the other Party. Initial designees of the Parties to the JPT shall be as follows:

CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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          2.2.3 Meetings.                (a)  Schedule of Meetings; Agenda . The JPT shall establish a schedule of times for regular meetings, in no event less frequently than once per [***] taking into account, without limitation, the planning needs of the Research Program and its responsibilities. In addition, special meetings may be convened by any member upon [***] days (or, if such meeting is proposed to be conducted by teleconference, upon [***] days) written notice to the other members; provided that (i) notice of any such special meeting may be waived at any time, either before or after such meeting, and such waiver shall be the equivalent to the giving of a valid notice hereunder, and (ii) attendance of any member at a special meeting shall constitute a valid waiver of notice from such member. Regular and special meetings of the JPT may be held in person or by teleconference or videoconference; provided that meetings held in person shall alternate between the respective offices of the Parties. The Chair shall prepare and circulate to each JPT member an agenda for each JPT meeting no later than [***] prior to such meeting.                (b)  Quorum; Voting; Decisions . At each JPT meeting, (i) the presence in person of at least [***] members designated by each Party shall constitute a quorum and (ii) all members designated by each Party who are present shall have [***] on all matters before the JPT at such meeting. All decisions of the JPT shall be made by unanimous vote. Alternatively, the JPT may act by written consent signed by at least [***] members designated by each Party. Whenever any action by the JPT is called for hereunder during a time period in which the JPT is not scheduled to meet, the Chair shall cause the JPT to take the action in the requested time period by calling a special meeting or by circulating a written consent. Representatives of each Party or of its Affiliates who are not members of the JPT (including, without limitation, the Patent Coordinators) may attend JPT meetings as non-voting observers without the consent of the other Party. In the event that the JPT is unable to resolve any matter before it, such matter shall be referred to the JMC to be resolved in accordance with Section 2.1.5.                (c)  Minutes . The JPT shall keep minutes of its meetings that record all decisions and all actions recommended or taken in reasonable detail. Drafts of the minutes CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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shall be prepared and circulated to the members of the JPT within a reasonable time after the meeting, not to exceed [***] business days. The chair shall have responsibility for the preparation and circulation of draft minutes. Each member of the JPT shall have the opportunity to provide comments on the draft minutes. The minutes shall be approved, disapproved and revised as necessary at the next JPT meeting. Upon approval, the chair of the JPT shall circulate final minutes of each meeting to the members of the JPT.                (d)  Expenses . ARCHEMIX and ELAN shall each bear all expenses of their respective JPT members related to their participation on the JPT and attendance at JPT meetings.           2.2.4 Responsibilities . The JPT shall be responsible for (i) overseeing the conduct and progress of the Research Program and (ii) recommending Program Aptamers to the JMC for nomination as Lead Compounds and Clinical Candidates. Without limiting the generality of the foregoing, the JPT shall have the following responsibilities:                (a) preparing or directing the preparation of, and recommending to the JMC for its approval, all Annual Research Plans and budgets therefor;                (b) preparing or directing the preparation of all amendments to JMC-approved Annual Research Plans as it deems appropriate in furtherance of the objectives of the Research Program as set forth in the Annual Research Plan and submitting such amendments to the JMC for its consideration;                (c) monitoring the progress of each Annual Research Plan and of each Party’s activities thereunder;                (d) providing a forum for consensual decision making with respect to the Research Program;                (e) reviewing data, reports or other information submitted by either Party with respect to work conducted in the Research Program; CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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               (f) preparing for the JMC on at least a semi-annual basis a progress report for the Research Program in reasonable detail and providing to the JMC such additional information as it may request;                (g) recommending amendments to the Lead Selection Criteria and Clinical Candidate Selection Criteria as it deems appropriate, in furtherance of the objectives of the Research Program as set forth in the Research Plan;                (h) considering the need for, and recommending as appropriate, the identification and research of Back-Up Collaboration Compounds;                (i) nominating Collaboration Compounds or IL-23 Aptamers as Lead Compounds for acceptance by the JMC;                (j) nominating Lead Compounds as Clinical Candidates for acceptance by the JMC;                (k) discussing all Annual Development Plans for Co-Developed Products in the applicable Co-Development Territory(ies), Indication and formulation;                (l) discussing all amendments to the Annual Development Plans described in Section 2.2.4(k), above and submitting such amendments to the JMC for its consideration;                (m) reviewing data, reports or other information submitted by either Party with respect to work conducted in the Development of Clinical Candidates that are, or are eligible for designation as, Co-Developed Products;                (n) preparing for the JMC on at least an annual basis a reasonably detailed progress report regarding the Development of Development Leads and Clinical Candidates that are, or are eligible for designation as, Co-Developed Products in the applicable Co-Development Territory(ies), Indication and formulation and providing to the JMC such additional information as it may reasonably request on this subject; CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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               (o) implementing a mutually acceptable mechanism for reporting Adverse Events between the Parties for each Development Lead, Clinical Candidate and Product;                (p) discussing strategies for the promotion and marketing of all Co-Developed Products in the applicable Co-Development Territory(ies), Indication and formulation if ELAN alone (rather than with or through a Sublicensee) is or will be promoting and marketing a Co-Developed Product; provided, that, ELAN agrees to use Commercially Reasonable Efforts to include the JPT rights set forth in this Section 2.2.4(p) in each Sublicense Agreement;                (q) discussing the Product Commercialization Plan for each Co-Developed Product in the applicable Co-Development Territory(ies), Indication and formulation, if ELAN alone (rather than with or through a Sublicensee) is or will be Commercializing a Co-Developed Product; provided, that, ELAN agrees to use Commercially Reasonable Efforts to include the JPT rights set forth in this Section 2.2.4(q) in each Sublicense Agreement;                (r) discussing the short-term and long-term sales forecasts for Co-Developed Products in the applicable Co-Development Territory(ies), Indication and formulation if ELAN alone (rather than with or through a Sublicensee) is or will be Commercializing a Co-Developed Product; provided, that, ELAN agrees to use Commercially Reasonable Efforts to include the JPT rights set forth in this Section 2.2.4(r) in each Sublicense Agreement;                (s) discussing all recalls, market withdrawals and any other corrective actions related to Co-Developed Products in the applicable Co-Development Territory(ies), Indication and formulation; and                (t) making any other decisions and performing such activities as may reasonably be delegated to the JPT pursuant to this Agreement or by mutual written agreement of the Parties after the Effective Date.           2.2.5 Interests of the Parties . Notwithstanding any other provisions of this Agreement, all decisions made and all actions taken by the JPT shall be made or taken in the best interest of the Collaboration. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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          2.2.6 Alliance Management . Each Party shall appoint a person who shall oversee contact between the Parties for all matters related to the Collaboration between meetings of the JMC and JPT and shall have such other responsibilities as the Parties may mutually agree in writing after the Effective Date (each, a "Collaboration Manager"). Each Party may replace its Collaboration Manager at any time by notice in writing to the other Party. The initial Collaboration Managers shall be:

3. RESEARCH PROGRAM      3.1 Implementation of the Research Program . The objectives of the Research Program shall be the identification of (i) Collaboration Compounds or IL-23 Aptamers for nomination by the JPT to the JMC for approval as Lead Compounds and (ii) Lead Compounds for recommendation by the JPT to the JMC as Clinical Candidates for Development with a view to the subsequent Commercialization of Products Derived therefrom. Except for the ELAN Research Activities, if any, which shall be conducted by ELAN at its sole expense, ARCHEMIX shall conduct the Research Program.      3.2 Research Plan; Annual Research Plans . The initial Annual Research Plan and budget, which describes the research activities to be carried out by each Party during the first Contract Year of the Research Program Term, shall be prepared by the JPT, submitted to the JMC for its approval and attached hereto as Exhibit A within [***] days of the Effective Date. For each Contract Year during the Research Program Term commencing with the second Contract Year, an Annual Research Plan and budget shall be prepared by or at the direction of the JPT and submitted to the JMC for its approval. The JPT shall manage the preparation of each Annual Research Plan in a manner designed to obtain JMC approval no later than [***] days prior to the end of the then-current Contract Year. Each Annual Research Plan shall: (a) set forth (i) the research objectives and activities to be performed for the Contract Year covered by the Annual Research Plan with reasonable specificity, (ii) the research plans and protocols to be employed to complete each stage of the Research Program, (iii) changes to the LSC, CCSC and CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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other criteria or changes thereto that the JPT will utilize to evaluate the results of the Research Program to nominate Lead Compounds and Clinical Candidates, (iv) the Party that shall be responsible for performing such activities, (v) a timeline and budget for such activities, and (vi) with respect to ARCHEMIX Research Activities and ELAN Research Activities, the number of FTEs estimated to be required to perform such activities and the corresponding FTE Cost for such activities; and (b) shall be consistent with the other terms of this Agreement. Without limiting the generality of the foregoing, the objectives of each Annual Research Plan shall include, as appropriate from time to time during the Research Program Term, conducting the necessary research activities to identify Collaboration Compounds or IL-23 Aptamers or to determine whether Collaboration Compounds, IL-23 Aptamers or Lead Compounds should be nominated to the JMC as Lead Compounds or Clinical Candidates, as applicable.      Except as provided in Section 5.2.1, ELAN shall fund a minimum of [***] ARCHEMIX FTEs in the aggregate during the three (3) year Research Program Term. Unless otherwise agreed by the Parties, the annual distribution of ARCHEMIX FTEs funded by ELAN shall equal the ARCHEMIX Annual FTE Commitment. The JPT shall have the right to increase the number of FTEs to be provided by ARCHEMIX for any Contract Year; provided, that, any increase, at ELAN’s request, in excess of the ARCHEMIX Annual FTE Commitment for any Contract Year shall be an ARCHEMIX Decision. Any Annual Research Plan may be amended from time to time by the JPT and submitted for approval by the JMC pursuant to 2.1.4. Each amendment, modification and update to the Annual Research Plan shall include the resulting changes to the budget and shall be set forth in a written document prepared by, or at the direction of, the JPT and approved by the JMC, shall specifically state that it is an amendment, modification or update to the Annual Research Plan and shall be attached to the minutes of the meeting of the JMC at which such amendment, modification or update was approved by the JMC. Without limiting the nature or frequency of any other amendments, modifications or updates to the Research Plan that may be approved by the JMC, the Annual Research Plan shall be updated at least once prior to the end of each Contract Year to describe the research activities to be carried out by each Party during the following Contract Year during the Research Program Term in conducting the Research Program pursuant to this Agreement. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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     3.3 Conduct of Research Program .           3.3.1 ARCHEMIX Responsibilities . During the Research Program Term, ARCHEMIX shall, subject to the provisions of Section 1.16, (a) use Commercially Reasonable Efforts to conduct the ARCHEMIX Research Activities assigned to it, using the number of FTEs set forth in the Annual Research Plan and (b) commit such resources other than personnel as are reasonably necessary to conduct such ARCHEMIX Research Activities. In the event that ARCHEMIX reasonably concludes in good faith that a Program Target may be a Failed Target, ARCHEMIX shall provide written notice to the JPT within [***] days of reaching such conclusion, providing bona fide scientific evidence in support of such conclusion. The JPT shall discuss the data and information generated with respect to such Program Target, and shall determine whether such Program Target shall be proposed to the JMC for designation as a Failed Target, as described in Section 3.9.           3.3.2 ELAN Responsibilities . During the Research Program Term, ELAN shall (a) pay ARCHEMIX the FTE Rate per FTE per Contract Year in accordance with Section 5.2, (b) commit such resources as are reasonably necessary to conduct the ELAN Research Activities set forth in the Annual Research Plan, and (c) use Commercially Reasonable Efforts to conduct the ELAN Research Activities set forth in the Annual Research Plan.           3.3.3 Compliance and Funding . Each Party shall perform its obligations under each Annual Research Plan and this Agreement using Commercially Reasonable Efforts in good faith and in compliance in all material respects with all Applicable Laws. For purposes of clarity, with respect to each activity performed under an Annual Research Plan or Annual Development Plan that will or would reasonably be expected to generate data to be submitted to a Regulatory Authority in support of a Regulatory Filing or Drug Approval Application, the Party performing such activity shall comply in all material respects with the regulations and guidance of the FDA that constitute Good Laboratory Practice or Good Manufacturing Practice (or, if and as appropriate under the circumstances, International Conference on Harmonization (ICH) guidance or other comparable regulation and guidance of any Regulatory Authority in any country or region in the Territory). Each Party shall be solely responsible for paying the salaries CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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and benefits of its employees and amounts due to consultants conducting its activities under Annual Research Plans.           3.3.4 Cooperation . Scientists at ARCHEMIX and ELAN shall cooperate in the performance of the Research Program and, subject to the terms of this Agreement and any confidentiality obligations to Third Parties, shall exchange such data, information and materials as are reasonably necessary or useful for the other Party to perform its obligations under any Annual Research Plan.           3.3.5 Purchase of Dedicated Equipment . If, during the Term of this Agreement, ELAN determines in its sole discretion that it is necessary or advisable to purchase Dedicated Equipment in order for ARCHEMIX to perform any ARCHEMIX Research Activities under the Research Program, then ELAN shall provide ARCHEMIX with written notice of such determination, and ARCHEMIX shall provide ELAN with the estimated price for such purchase and quality parameters for such Dedicated Equipment, for ELAN’s approval of such price and features. Promptly after the consummation of such purchase, if approved, ARCHEMIX shall provide ELAN with a copy of the invoice or invoices reflecting such purchase, and ELAN shall reimburse ARCHEMIX for the purchase of all such Dedicated Equipment within thirty (30) days of its receipt of such invoice; provided, however, that no costs reimbursed by ELAN hereunder (or depreciation of such purchased equipment or instruments) shall be included within the calculation of any Development Costs under this Agreement. ELAN shall retain title and ownership of all such Dedicated Equipment and, at its expense upon reasonable notice to ARCHEMIX, shall have the right to remove such Dedicated Equipment from ARCHEMIX’ facilities, at such time as such Dedicated Equipment is no longer required for use by ARCHEMIX in the conduct of the Research Program. As used in this section, "Dedicated Equipment" means any equipment, instrument or machinery used by ARCHEMIX exclusively in the conduct of the Research Program.      3.4 Records.           3.4.1 Record Keeping. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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               (a)  Research Program Records . Each Party shall maintain complete and accurate records of its activities in the Research Program in sufficient detail, in good scientific manner and otherwise in a manner that reflects all work done and results achieved. Subject to Article 6, each Party shall provide the other Party with access during normal business hours and upon reasonable advance notice to inspect and copy such records, including without limitation laboratory notebooks, to the extent reasonably required for the performance of the requesting Party’s obligations and/or exercise of the requesting Party’s rights under this Agreement, provided that the audited Party may redact information not relevant to the Research Program prior to such audit. Notwithstanding the foregoing, except for purposes of the information-sharing and cooperation provisions of Articles 8 and 9, ELAN shall not have the right to audit or copy any records that relate to work done on any Terminated Program Aptamer after the date that an Aptamer or Collaboration Compound has become a Terminated Program Aptamer.                (b)  Record-Keeping Policies . Without limiting the generality of Section 3.4.1(a), each Party agrees to maintain a policy that requires its employees and consultants to record and maintain all data and information developed during the Research Program.           3.4.2 Reports . ARCHEMIX shall keep the JPT regularly informed of the progress of the Research Program. Without limiting the generality of the foregoing, ARCHEMIX shall, at least once each [***] during the Research Program Term, (a) provide reports to the JPT in reasonable detail regarding the status of its activities under the Research Program, (b) advise the JPT of its identification of Collaboration Compounds and IL-23 Aptamers and provide the JPT with any supporting data applicable to such Collaboration Compounds and IL-23 Aptamers, (c) provide the JPT with the results of activities conducted in the Research Program with respect to each Collaboration Compound and IL-23 Aptamer so as to enable the JPT to determine whether such Collaboration Compound or IL-23 Aptamer meets the LSC and should be proposed to the JMC as a Lead Compound, (d) provide the JPT with the results of activities conducted in the Research Program with respect to each Lead Compound so as to enable the JPT to determine whether such Lead Compound meets the CCSC and should be CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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proposed to the JMC as a Clinical Candidate and (e) provide to the JPT such additional information that it has in its possession as may be reasonably requested from time to time by the JPT. ELAN shall provide the JPT, on at least a [***], with reports in reasonable detail regarding the status of all ELAN Research Activities and such additional information that it has in its possession as may be reasonably requested from time to time by the JPT.      3.5 Selection of Program Targets.           3.5.1 Selection of Program Targets.                (a)  Selection and Rejection of Program Targets . The Parties hereby acknowledge that (i) three (3) initial Program Targets in addition to IL-23 have been designated by the Parties as of the Effective Date, and (ii) the Research Program will initially include work on IL-23 and [***] as Program Targets, as set forth in the Annual Research Plan. If, at any time during the Research Program Term, ELAN decides that it wishes to replace a Program Target with another Target, then (a) it shall provide written notice of such decision to ARCHEMIX, which notice shall state the reason for ELAN’s decision, (b) all activities with respect to such Program Target under the Research Program shall immediately cease, and (c) such Program Target shall be deemed to be a Rejected Program Target as of the date of such written notice.                (b)  Replacement of Program Targets .                     (i)  Replacement Right . ELAN shall have the right at any time during the Research Program Term to propose that any additional Target that ELAN reasonably believes based on published literature or proprietary data is useful within the Target Selection Field and that is not an Excluded Target replace a Program Target, by providing written notice to ARCHEMIX. ARCHEMIX shall accept or refuse the additional Target within [***] days after receipt of such notice from ELAN. A Target proposed by ELAN for inclusion in the Research Program shall only be refused by ARCHEMIX in good faith, and only if: (1) it is an [***], (2) ARCHEMIX is prohibited by an executed contract from licensing Aptamers against such Target to ELAN, subject to the procedure set forth in the definition of ARCHEMIX Decision (Section 1.16(e)), (3) ARCHEMIX is in active negotiations, as[***] by [***] with a Third Party with respect to a license, collaboration or similar agreement relating to Aptamers against such Target, CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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(4) ARCHEMIX is developing, and has not ceased developing, for its own benefit, Aptamers against such Target as [***] by the [***] of the [***] such [***] ARCHEMIX’ [***] (or [***]) of the [***] of such [***], or (5) it is a [***]. As promptly as practicable after designation of a new Program Target or the decision to initiate research on a Program Target listed on Schedule 4 as of the Effective Date, the JPT shall (A) develop and submit to the JMC for its approval the LSC and CCSC for such Target and (B) prepare an update to the Annual Research Plan to include the ARCHEMIX Research Activities to be conducted to identify Collaboration Compounds against such Program Target for potential nomination as a Lead Compound and to identify one or more Lead Compounds against such Program Target for potential nomination as a Clinical Candidate.                     (ii)  Designation by ELAN . At the time of nomination of a new or replacement Program Target, ELAN shall (a) designate the Program Target (describing the applicable ligand, receptor and any subunits [***]) to be [***] in [***]the [***], such [***] to be [***] on [***] in the[***] or [***] ELAN, and (b) [***] ARCHEMIX’ [***] ARCHEMIX [***] ELAN [***] in [***] such [***] such [***] and any [***] and [***]). In [***], if [***] the [***] of a [***] and its [***] or [***], ELAN [***] on [***] or [***] that the [***] other [***] or [***], ELAN [***] ARCHEMIX [***] which [***] such [***] or [***] and (b) [***] ARCHEMIX’ [***] the [***] upon [***] ELAN [***] in [***] such [***] or [***] ARCHEMIX’ [***] of such [***], such [***] or [***] shall be [***] to be [***] of the [***]such [***] or [***] may be [***] ARCHEMIX [***]Section 3.5.1(b). [***] to the [***], ARCHEMIX’ [***] of the [***] such [***] or [***] to the [***]ELAN’s [***] shall not be [***] to be a [***] of this [***].                     (iii)  Release of Restrictions . ARCHEMIX shall give ELAN prompt written notice during the Research Program Term if the restrictions on any Excluded Target described in Sections 3.5.1(b)(i)(1)(2)(3) or (4) lapse, or are otherwise terminated, such that the previously refused Target becomes eligible for inclusion as a Program Target.                     (iv)  Termination of Replacement Right . Notwithstanding anything to the contrary in this Agreement, ELAN’s right to replace Program Targets pursuant to Section 3.5.1(b)(i) shall terminate on the [***] of [***] of the [***] by [***] of the [***]. CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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          3.5.2 Limitation on Number of Program Targets . ARCHEMIX shall not be required to work on more than [***] Program Targets (including IL-23) at any given time during the Research Program Term; provided, that (a) any Program Target that becomes a [***] or [***] shall not be counted as a Program Target for purposes of this limitation, and (b) this Section 3.5.2 shall not limit or otherwise affect ARCHEMIX’ obligation to consider in good faith using its commercially reasonably discretion any request of ELAN to work on additional Program Targets and/or apply additional resources to the Research Program beyond those contemplated by the Annual Research Plan.      3.6 Identification of Collaboration Compounds, IL-23 Aptamers and Lead Compounds .           3.6.1 Identification of Program Oligonucleotides . ARCHEMIX shall use Commercially Reasonable Efforts in good faith to perform the SELEX™ Process to identify Program Oligonucleotides in accordance with each Annual Research Plan, as amended.           3.6.2 Lead Compounds . Within [***] days after its receipt of each report from ARCHEMIX identifying a Collaboration Compound or IL-23 Aptamer which ARCHEMIX reasonably believes meets the applicable LSC (or which ARCHEMIX otherwise reasonably believes should be a Lead Compound), the JPT shall review the data and information and determine whether to nominate the Collaboration Compound or IL-23 Aptamer for designation by ELAN as a Lead Compound. Once the JPT has reached a decision regarding nomination of any such Collaboration Compound or IL-23 Aptamer as a Lead Compound, the JPT shall promptly furnish all available information to ELAN. ELAN shall consider such nomination within [***] days, and if ELAN determines that the Collaboration Compound or IL-23 Aptamer meets the LSC or is otherwise acceptable and so advises ARCHEMIX in writing, such Collaboration Compound or IL-23 Aptamer shall be designated a "Lead Compound" for purposes of this Agreement. As of the Effective Date, the ARC2350 Aptamer shall be deemed to be a Lead Compound.      3.7 Clinical Candidates . Within [***] days after its receipt of each report from ARCHEMIX identifying a Lead Compound which ARCHEMIX reasonably believes meets the applicable CCSC (or which ARCHEMIX otherwise reasonably believes should be a candidate CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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for Development), the JPT shall review the data and information and determine whether to nominate the Lead Compound for designation as a Clinical Candidate. Once the JPT has reached a decision regarding nomination of any such Lead Compound, the JPT shall promptly furnish all available information to ELAN. ELAN shall consider such nomination within [***] days, and if ELAN determines that the Lead Compound meets the CCSC or is otherwise acceptable to ELAN and so advises ARCHEMIX in writing, such Lead Compound shall be designated a "Clinical Candidate" for purposes of this Agreement. 3.8 Identification of Back-up Collaboration Compounds .           3.8.1 Back-Up Collaboration Compounds . Subject to the terms set forth in the definition of ARCHEMIX Decision, for each Lead Compound or Clinical Candidate approved by ELAN or the JMC, as applicable, upon the written request of ELAN, ARCHEMIX will use Commercially Reasonable Efforts to conduct ARCHEMIX Research Activities in order to deliver to ELAN [***] Aptamers, in [***] to the [***] or [***], which may be [***] as a [***] Aptamer [***] the [***] Aptamers [***] in [***] from such [***] or [***] Aptamer, a [***] All activities conducted by ARCHEMIX to identify each Back-Up Collaboration Compound shall be performed as ARCHEMIX Research Activities as part of the Research Program and the Annual Research Plan shall be amended accordingly. The rights and obligations of the Parties relating to each Back-Up Collaboration Compound shall be identical to those applicable to the accompanying Lead Compound or Clinical Candidate, except as may be otherwise expressly provided herein.           3.8.2 Back-Up Notices . ELAN shall notify ARCHEMIX in writing in the event ELAN determines to replace a Lead Compound or Clinical Candidate with the applicable Back-Up Collaboration Compound or to Develop the Back-Up Collaboration Compound in addition to the Lead Compound or Clinical Candidate. Subsequent to such notice, any reference to the Lead Compound or Clinical Candidate shall be deemed (as applicable) either to include, or to be made to, the Back-Up Collaboration Compound for the purposes of this Agreement.      3.9 Failed Targets . If at any time during the Research Program the JPT determines, and the JMC agrees, that a Program Target shall be designated as a Failed Target, all research activities directed to such Failed Target shall cease, and ELAN shall, to the extent and as CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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provided for in Section 3.5, select a new Program Target, and such Failed Target shall no longer be considered a part of the Research Program.      3.10 Supply of Proprietary Materials . From time to time during the Research Program Term, either Party (the "Transferring Party") may supply the other Party (the "Recipient Party") with Proprietary Materials Controlled by the transferring Party for use in the Research Program. Each Recipient Party hereby agrees that (a) it shall not use the other party’s Proprietary Materials for any purpose other than exercising its rights or performing its obligations hereunder; (b) it shall use such Proprietary Materials only in compliance with all Applicable Laws; (c) it shall not transfer any such Proprietary Materials to any Third Party without the prior written consent of the Transferring Party, except as expressly permitted in this Agreement; (d) the Recipient Party shall not acquire any right, title or interest in or to such Proprietary Materials solely as a result of such supply by the Transferring Party; and (e) upon the expiration or termination of the Research Program Term, the Recipient Party shall, if and as instructed by the Transferring Party, either destroy or return any such Proprietary Materials that are not the subject of the grant of a continuing license hereunder.      3.11 Research Program Term . The Research Program shall commence on the Effective Date and shall continue until the last day of the Research Program Term. In the event ELAN decides to seek an extension of the Research Program beyond the third Contract Year, it will promptly notify ARCHEMIX. ELAN will use commercially reasonable efforts to make any such decision and notify ARCHEMIX at least [***] months prior to the end of the then-current Research Program Term. 4. DEVELOPMENT PROGRAM; COMMERCIALIZATION OF PRODUCTS [***]      4.1 Objectives of the Development Program . The objectives of the Development Program shall be the Development of Clinical Candidates to enable the Commercialization of Products in the Territory.      4.2 Responsibility for Development of Clinical Candidates and Commercialization of Products . Except for the ARCHEMIX Development Activities, if any, to be conducted by ARCHEMIX and subject to Section 4.11.1(c), ELAN shall have the sole right CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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and responsibility (subject to Sections 4.6 and 7.3), at its sole expense, to conduct all aspects of the Development of Lead Compounds and Clinical Candidates in accordance with the applicable Annual Development Plan, and all aspects of the Commercialization of Products in accordance with the applicable Product Commercialization Plan, in the Territory, including, without limitation, the conduct of: (i) all IND-enabling non-clinical studies that are outside of the Research Program; (ii) all activities related to human clinical trials (including, without limitation, Phase I Clinical Trials, Phase II Clinical Trials and Phase III Clinical Trials); (iii) subject to ARCHEMIX’ rights under Section 4.5, all activities relating to the manufacture and supply of Clinical Candidates and Products (including all required process development and scale up work with respect thereto) for Development and Commercialization purposes; and (iv) all pre-marketing, marketing, promotion, sales, distribution, import and export activities (including securing reimbursement, conducting sales and marketing activities, recalls, withdrawals, any post-marketing trials or post-marketing safety surveillance, and maintaining databases) for Products, subject to the oversight of the JPT. Without limiting the generality of the foregoing, ELAN shall have the sole right and responsibility (subject to Section 4.6), at its sole expense, (i) to make all Regulatory Filings for Clinical Candidates and Products and file all Drug Approval Applications and otherwise seek Regulatory Approvals for Products, as well as to conduct all correspondence and communications with Regulatory Authorities regarding such matters and (ii) to report Adverse Events to Regulatory Authorities if and to the extent required by Applicable Laws. All Regulatory Approvals for Products shall be owned by ELAN, subject to Section 10.3 and 10.4.      4.3 Annual Development Plans . Subject to Section 4.11.1(c), within [***] days after the designation pursuant to Section 3.7 of a Clinical Candidate eligible for designation as a Co-Developed Product, ELAN shall prepare an Annual Development Plan and budget for Development of such Clinical Candidate for the balance of the Contract Year during which the recommendation of such Clinical Candidate is approved. Thereafter, for each Contract Year during the Term in which such Clinical Candidate is so eligible, and for each Co-Developed Product in the applicable Co-Development Territory, Indication and formulation, ELAN shall prepare and submit to the JMC for its review, an Annual Development Plan and Development CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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budget for each Clinical Candidate and/or Co-Developed Product. Each Annual Development Plan shall: (a) set forth (i) the Development objectives, activities, priorities, timelines, budget and resources for the Contract Year covered by the Annual Development Plan with reasonable specificity, (ii) which activities are ARCHEMIX Development Activities, (iii) with respect to such ARCHEMIX Development Activities, the number of FTEs estimated to be required to perform such activities and the corresponding FTE Cost, and (iv) the expected Regulatory Filings and Drug Approval Applications to be prepared and filed and the expected timetable of completing such Development activities; and (b) be consistent with the other terms of this Agreement. The initial Annual Development Plan shall be prepared by ELAN and submitted to the JMC for its review within [***] days of the day on which the JMC approves the selection of a Clinical Candidate based on a Lead Compound and in any event, on or prior to the initiation of Development activities with respect to the initial Clinical Candidate. Each amendment, modification and update to any such Annual Development Plan shall include the resulting changes to the budget and shall be set forth in a written document prepared by ELAN and submitted to the JMC, shall specifically state that it is an amendment, modification or update to that Annual Development Plan and shall be attached to the minutes of the meeting of the JMC at which such amendment, modification or update was reviewed by the JMC. Without limiting the nature or frequency of any other amendments, modifications or updates to the Annual Development Plan, such Annual Development Plan shall be updated at least once prior to the end of each Contract Year in which an Annual Development Plan has been approved to describe the Development activities to be carried out by each Party during the following Contract Year in conducting the applicable Development Program pursuant to this Agreement.      4.4 Product Commercialization Plans . Subject to Section 4.11.1(c), if ELAN alone (rather than with or through a Sublicensee) is marketing a Co-Developed Product, within [***] days after the Initiation of the first Phase III Clinical Trial for a Co-Developed Product, ELAN shall prepare and provide to the JPT for its review and discussion a Product Commercialization Plan for each Co-Developed Product in the applicable Co-Development Territory(ies), Indication and formulation, and shall update and submit such Product Commercialization Plan to the JPT for review and discussion not less than annually; provided, that, ELAN shall use Commercially CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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Reasonable Efforts to include the obligations set forth in this Section 4.4 in each Sublicense Agreement.      4.5 Supply of Products for Development and Commercialization .           4.5.1 Negotiation by the Parties . The Parties shall discuss in good faith the manufacturing responsibilities for each Product that is Developed and Commercialized under this Agreement as set forth in this Section 4.5.           4.5.2 ARCHEMIX Right to Supply Products . ARCHEMIX shall have the right, but not the obligation, to exercise a time-limited option to enter into negotiations with ELAN for a separate supply and quality agreement detailing the terms under which ARCHEMIX would manufacture by itself (not by or through a Third Party manufacturer), and supply the active pharmaceutical ingredient for any Product to ELAN (the "Supply Agreement"). ARCHEMIX may exercise its Supply Agreement option as to any Product by providing ELAN with written notice at any time prior to the Initiation of the first Phase III Clinical Trial for such Product. If ARCHEMIX provides such written notice and reasonably appears able to supply the Product without impeding the Product Commercialization Plan, delaying the timeframe planned for Regulatory Approval and Product launch or limiting the Product shelf life, ARCHEMIX and ELAN shall negotiate in good faith for up to [***] days following ELAN’s receipt of such notice to enter into the Supply Agreement, which would include, without limitation, the provisions described in Section 4.5.3. For clarity, nothing contained in this Section 4.5.2 shall constitute an offer by ARCHEMIX to sell any Product, and neither Party shall be obligated to enter into any Supply Agreement. If the Parties do not enter into a Supply Agreement for such Product within such time period, then ELAN shall have no further obligation to ARCHEMIX with respect to such Product.           4.5.3 Essential Terms of Supply . Any Supply Agreement entered into between the Parties shall contain the following terms and conditions, as well as other terms and conditions typically contained in supply agreements for products of similar nature and market potential: CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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               (a) ELAN shall order amounts of Products, and ARCHEMIX shall deliver all such ordered amounts, in accordance with specified forecasting parameters, advance ordering timeframes and delivery timeframes to be agreed upon by the Parties;                (b) ARCHEMIX shall deliver such amounts of Products meeting applicable specifications and legal requirements ordered in accordance with the foregoing (including such agreed upon timeframes) in a timely manner;                (c) ELAN shall have appropriate remedies for the failure of ARCHEMIX to perform its obligations specified in (b), including without limitation that ELAN shall have the right to manufacture the Product itself or select a Third Party manufacturer if ARCHEMIX fails to perform such obligations;                (d) the transfer price for supply of Product to ELAN shall be agreed upon by the Parties and set forth in such agreement,                (e) all Products supplied by ARCHEMIX shall be supplied FCA place of manufacture, Incoterms 2000;                (f) ARCHEMIX shall maintain a commercially reasonable backup supply of Product at one remote location to ensure ARCHEMIX’ ability to supply continuously Products to ELAN in accordance with such agreement;                (g) ELAN shall have the right to establish a second source, within or outside of ELAN, if ELAN’s requirements of Products cannot be met despite ARCHEMIX’ meeting its obligations under (b);                (h) ARCHEMIX shall provide reasonable assistance to ELAN and/or any Third Party manufacturer, as applicable, that assumes responsibility for manufacturing Product to enable ELAN or such Third Party to make Products in the manner then made by ARCHEMIX, and shall grant all licenses necessary for such purpose;                (i) ELAN shall have the right to inspect the packaging and labeling prior to use, and upon reasonable notice to inspect the plant and premises used, and processes CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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and records of the packaging and storage employed, by ARCHEMIX in connection with manufacture and supply of Product; and                (j) If the Supply Agreement is terminated other than because of a material breach by ELAN, a provision similar in effect to Section 10.3.1(g) of this Agreement shall govern ARCHEMIX’ obligation to continue to supply Products to ELAN.      4.6 Development and Commercialization Diligence .           4.6.1 General Diligence Obligations . ELAN and its Affiliates shall exercise Commercially Reasonable Efforts during the Term to conduct the ELAN Development Activities and to Commercialize Products in the Territory. ARCHEMIX and its Affiliates shall exercise Commercially Reasonable Efforts during the Term to conduct ARCHEMIX Development Activities, as applicable.           4.6.2 Specific Diligence Obligations .                (a)  Specific Diligence Obligations . During the Term, ELAN shall use Commercially Reasonable Efforts (i) to Develop at [***] Clinical Candidate targeted at IL-23 and to Commercialize [***]IL-23 Product for each Diligence Indication in the United States and a Major Market Country, and (ii) to Develop [***]Clinical Candidate targeted at each Program Target other than IL-23 and to Commercialize [***]Collaboration Product for each active Program Target other than IL-23 in the United States and a Major Market Country.                (b)  Effect of Breach of Diligence Obligations . If ARCHEMIX at any time believes that ELAN is not meeting a diligence obligation pursuant to Section 4.6.2(a), ARCHEMIX may give written notice to ELAN requesting written justification, in the form of detailed reasons that would support the proposition that ELAN is meeting such diligence obligations. In such event, ELAN shall provide such written justification to ARCHEMIX within [***] days after such notice is given. In the event that ARCHEMIX does not agree with such justification, then the Parties shall meet within [***] days after such justification is given to discuss the basis for ARCHEMIX’ belief that ELAN has failed to meet such diligence obligation. If ARCHEMIX does not receive ELAN’s justification within [***] days after ARCHEMIX first provides such a notice to ELAN, or if ARCHEMIX, following any such CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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meeting occurring within such [***] day time period, still believes that ELAN has not met its diligence obligation pursuant to Section 4.6.2(a), then ARCHEMIX shall have the right, in its sole discretion, to exercise any or all rights or remedies that it may have under this Agreement, at law or in equity.      4.7 Compliance . Each Party shall perform its obligations under each Annual Development Plan and this Agreement using Commercially Reasonable Efforts in good faith and in compliance in all material respects with all Applicable Laws. For purposes of clarity, with respect to each activity performed under an Annual Development Plan that will or would reasonably be expected to generate data to be submitted to a Regulatory Authority in support of a Regulatory Filing or Drug Approval Application, the Party performing such activity shall comply in all material respects with, if and as applicable, the regulations and guidance of the FDA that constitute Good Laboratory Practice, Good Manufacturing Practice or Good Clinical Practices, (or, if and as appropriate under the circumstances, International Conference on Harmonization (ICH) guidance or other comparable regulation and guidance of any Regulatory Authority in any country or region in the Territory). Each Party shall be solely responsible for paying the salaries and benefits of its employees and amounts due to consultants conducting its activities under Annual Development Plans.      4.8 Cooperation . Scientists at ARCHEMIX and ELAN shall cooperate in the performance of each Development Program and, subject to the terms of this Agreement and any confidentiality obligations to Third Parties, shall exchange such data, information and materials as are reasonably necessary for the other Party to perform its obligations under any Annual Development Plan. 4.9 Exchange of Reports; Information; Updates .           4.9.1 Development Program Reports . Each Party shall keep the JPT generally informed of the progress of its efforts to Develop Clinical Candidates in the Territory. Without limiting the generality of the foregoing, each Party shall, on at least a [***], provide the JPT with reports in reasonable detail regarding the status of all preclinical IND-enabling studies and activities (including toxicology and pharmacokinetic studies), clinical trials and other activities conducted by or on behalf of each Party under the Development Program with respect to any CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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Development Lead or Clinical Candidate that is being Co-Developed or is eligible for Co-Development, or any Co-Developed Product, together with such additional information in its possession as may be reasonably requested from time to time by the JPT.           4.9.2 Commercialization Reports . ELAN shall keep the JPT generally informed of the progress of ELAN’s efforts to Commercialize Products in the Territory through periodic updates. Without limiting the generality of the foregoing, if ELAN alone (rather than with or through a Sublicensee) is Commercializing a Co-Developed Product, ELAN shall provide the JPT with [***] written updates to each Product Commercialization Plan for each Co-Developed Product in the applicable Co-Development Territory(ies), Indication and formulation, which shall (a) summarize ELAN’s efforts to Commercialize such Co-Developed Product in the applicable Co-Development Territory(ies), Indications and formulations, (b) identify the Regulatory Filings and Drug Approval Applications with respect to such Co-Developed Product that ELAN or any of its Affiliates or Sublicensees have filed, sought or obtained in the prior [***] month period or reasonably expect to make, seek or attempt to obtain in the following [***] month period and (c) to the extent not prohibited by Applicable Laws, summarize all post-marketing clinical and other data generated by ELAN with respect to such Co-Developed Product in the applicable Co-Development Territory(ies), Indication and formulation; provided, that, ELAN agrees to use Commercially Reasonable Efforts to include the obligations set forth in this Section 4.9.2 in each Sublicense Agreement. In addition, each Party (but not a Sublicensee) shall be required to provide such additional information that it has in its possession as may be reasonably requested from time to time by the JPT and/or the JMC regarding the Commercialization of any Product; provided, that, ELAN agrees to use Commercially Reasonable Efforts to include the foregoing obligation in each Sublicense Agreement.           4.9.3 Adverse Event Reports; Review of Regulatory Filings and Correspondence .                (a)  Adverse Events . In addition to the updates described in Section 4.9.1 and 4.9.2, ELAN shall provide ARCHEMIX with all Adverse Event information and product complaint information relating to Clinical Candidates or Products as such information is compiled or prepared by ELAN in the normal course of business within time frames consistent CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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with reporting obligations under Applicable Laws. All such Adverse Event and product complaint information shall be sent to ARCHEMIX in accordance with Section 13.1 and shall constitute Confidential Information of ELAN; provided, that, ARCHEMIX shall have the right to disclose any Serious Adverse Event to Third Parties solely to the extent required by Applicable Laws (including, without limitation, any applicable regulations of the FDA) or as required in writing by the FDA.                (b)  Preparation of Drug Approval Applications . Except as provided in Section 4.9.3(d) and (e), ELAN shall (i) consult with ARCHEMIX in good faith in the preparation of all Drug Approval Applications for Co-Developed Products for the applicable Indication and formulation and (ii) consider all comments of ARCHEMIX in good faith, taking into account the best interests of the Collaboration and of the Co-Development of the applicable Clinical Candidate and Commercialization of the applicable Co-Developed Product for the applicable Indication and formulation on a global basis.                (c)  Regulatory Meetings; Review of Other Regulatory Filings and Correspondence . Except as provided in Section 4.9.3(d), ELAN shall (i) use reasonable efforts to provide ARCHEMIX with at least [***] days advance notice of any meeting with the FDA or other Regulatory Authority regarding a Drug Approval Application relating to, or Regulatory Approval for, any Clinical Candidate that is being Co-Developed or is eligible for Co-Development, or any Co-Developed Product, and ARCHEMIX may elect to send one person reasonably acceptable to ELAN to participate (at ARCHEMIX’ sole cost and expense) solely as an observer in such meeting; (ii) subject to any Third Party confidentiality obligations, provide ARCHEMIX with drafts of each Regulatory Filing or other material regulatory document or correspondence with a Regulatory Authority pertaining to any Clinical Candidate that is being Co-Developed or is eligible for Co-Development or any Co-Developed Product and is prepared for submission to the FDA or other Regulatory Authority, sufficiently in advance of submission so that ARCHEMIX may review and comment on the substance of such Regulatory Filing or other document or correspondence; and (iii) promptly provide ARCHEMIX with copies of any document or other correspondence received from the FDA pertaining to any Clinical Candidate that is being Co-Developed or is eligible for Co-Development, or any Co-Developed Product. If CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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ARCHEMIX has not commented on such Regulatory Filing or other document or correspondence within [***] days (or, in the case of an IND, [***] days) after it is provided to ARCHEMIX, then ARCHEMIX shall be deemed to have no comments on such Regulatory Filing or other documents or correspondence. ELAN shall consider all comments of ARCHEMIX in good faith.                (d)  Co-Developed Products . ELAN shall (i) use reasonable efforts to provide ARCHEMIX with copies of each Regulatory Filing or other material regulatory document or correspondence with a Regulatory Authority pertaining to any Clinical Candidate that is being Co-Developed or is eligible for Co-Development and any Co-Developed Product so that ARCHEMIX may review and provide comment on the substance of such Regulatory Filing or other document or correspondence and (ii) promptly provide ARCHEMIX with copies of any document or correspondence received from the FDA pertaining to such Clinical Candidate or Co-Developed Product.      4.10 Development and Commercialization Rights and Restrictions .           4.10.1 Development and Commercialization Rights . Except as provided in this Section 4.10 or Section 4.11.1(c), ELAN shall have the exclusive right during the Term to Develop Clinical Candidates and Commercialize Products in the Territory.           4.10.2 Right of First Negotiation for [***] . If at any time during the Term, ARCHEMIX determines to formally pursue an [***] Agreement, ARCHEMIX shall give written notice to ELAN (the "[***] Opportunity Notice") describing and specifying the status of Development of the Technology, Patent Rights and particular products that ARCHEMIX reasonably expects to be involved in the [***] Agreement. ELAN shall have [***] days following the date that the [***] Opportunity Notice is given by ARCHEMIX (the "[***] Notice Period") to give written notice to ARCHEMIX that it wishes to enter into negotiations with ARCHEMIX with respect to such [***] Agreement (an "[***]ROFN Notice"); provided that, if ELAN determines not to give an [***]ROFN Notice prior to expiration of the [***] Notice Period, it shall in good faith provide written notice to ARCHEMIX promptly upon such determination that it declines to enter into negotiations. If ELAN gives written notice within the [***] Notice Period that it wishes to enter into negotiations with ARCHEMIX, the Parties shall CONFIDENTIAL Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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negotiate in good faith with respect to an [***] Agreement for a period of up to [***] days from the end of the [***] Notice Period. If the Parties do not agree upon financial terms with respect to the [***] Agreement within the [***] day negotiation period, ARCHEMIX shall thereafter have no obligation to ELAN with respect thereto and shall have the unencumbered right to negotiate and execute an