COLLABORATIVE RESEARCH AND LICENSE AGREEMENT

Exhibit 10.34 COLLABORATIVE RESEARCH AND LICENSE AGREEMENT between ARCHEMIX CORP. and MERCK, KGaA January 17, 2007 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

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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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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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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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 January 17, 2007, by and between Archemix Corp., a Delaware corporation with offices at 300 Third Street, Cambridge, MA 02142 ("ARCHEMIX"), and Merck KGaA, a company organized under the laws of Germany with offices at Frankfurter Str. 250, 64293 Darmstadt, Germany ("MERCK"). Each of MERCK and ARCHEMIX is sometimes referred to individually herein as a "Party" and collectively as the "Parties."      WHEREAS, ARCHEMIX has developed and controls certain technology, patent rights and proprietary materials related to (a) the identification and optimization of aptamers using its proprietary SELEX™ process and SELEX™ technology, and (b) the use of such aptamers for treating, preventing or delaying onset or progression of human diseases or conditions; and      WHEREAS, MERCK 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 identifying aptamers against certain identified targets, and developing and commercializing products derived from such aptamers for the prevention, treatment and delay of onset or progression of cancer.      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 and in Schedule 9 attached hereto shall have the meanings specified.      1.1 " 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 Development Candidate or Product, whether or not considered related to the Development Candidate or Product, including, without limitation, any undesirable sign (including abnormal laboratory findings of clinical concern), symptom or disease associated with the use of such Development Candidate or Product.      1.2 " Affiliate " means, with respect to any Person, any other Person that, directly or indirectly through one or more affiliates, 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, or 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 other than a corporation.      1.3 " Annual Development Plan " means, with respect to each Optimized Lead Compound and Development Candidate and Contract Year, the written plan for the Development 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.

Program for such Optimized Lead Compound and Development Candidate for such Contract Year, as such written plan may be amended, modified or updated, as further described in Section 4.3.      1.4 " Annual Net Sales " means, with respect to any Calendar Year, the aggregate amount of the Net Sales for such Calendar Year.      1.5 " Annual Research Plan " means the written plan describing the research 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 well as a budget therefore, as such written plan may be amended, modified or updated, as further described in Section 3.2.      1.6 " Applicable Laws " means Federal, state, local, national and supra-national laws, statutes, rules and regulations, including any rules, regulations, guidance, guidelines 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.      1.7 " Aptamer " means (a) any naturally or non-naturally occurring oligonucleotide identified by ARCHEMIX through the SELEX® Process that binds with high specificity and affinity to a Target; and (b) any oligonucleotide Derived from the oligonucleotide of (a) that has such high specifity and affinity.      1.8 " ARCHEMIX Background Technology " means any Technology that is used by ARCHEMIX, or provided by ARCHEMIX for use, in the Research Program and/or the Development Program that is (a) Controlled by ARCHEMIX as of the Effective Date or (b) conceived or first reduced to practice 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 any material respect of any MERCK Technology (other than Collaboration Aptamers), MERCK Patent Rights or MERCK Materials. For purposes of clarity, ARCHEMIX Background Technology (a) shall include the SELEX® Process and SELEX® Technology and (b) shall not include Collaboration Aptamers, ARCHEMIX Program Technology or ARCHEMIX’s interest in Joint Technology.      1.9 " ARCHEMIX Decision " means a decision with respect to the following issues: (a) the conduct of the [***] against [***]; (b) whether ARCHEMIX is to incur any [***]; (c) whether ARCHEMIX is to be obligated to perform any [***]; (d) whether ARCHEMIX is to incur any [***] in the performance of [***] or [***]; (e) the expansion, at MERCK’s request, of the number of FTEs to be provided by ARCHEMIX under the Research Program beyond [***] in any [***]; and (f) the inclusion of any [***] MERCK as [***] Program Target.      1.10 " ARCHEMIX Development Activities " means all Development activities specified to be conducted by ARCHEMIX in any Annual Development Plan (or amendment thereto) and approved by ARCHEMIX’s representatives on the JPT and JSC (without resort to the dispute resolution procedures set forth in Section 2.1.6). 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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     1.11 " ARCHEMIX-Gilead License Agreement " means the License Agreement between Gilead Sciences, Inc. and ARCHEMIX dated October 21, 2001, as amended.      1.12 " 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 and/or the Development Program. For purposes of clarity, ARCHEMIX Materials shall include all Aptamers provided by ARCHEMIX for use in the Research Program.      1.13 " ARCHEMIX Patent Rights " means any Patent Rights Controlled by ARCHEMIX that contain one or more claims that cover ARCHEMIX Technology.      1.14 " ARCHEMIX Program Technology " means (a) any oligonucleotide of an Enriched Pool that is not a Program Oligonucleotide; (b) any Program Technology that is conceived or first reduced to practice by employees of, or consultants to, ARCHEMIX, alone or jointly with any Third Party, without the use in any material respect of any MERCK Technology (other than Collaboration Aptamers), MERCK Patent Rights, MERCK Materials or Joint Technology; and (c) any Program Technology, regardless of whether conceived or first reduced to practice by employees of, or consultants to, ARCHEMIX, MERCK, or both Parties, alone or jointly with any Third Party, that relates to, or constitutes, the SELEX® Process or SELEX® Technology. For purposes of clarity, ARCHEMIX Program Technology does not include Program Generic Technology, Program Aptamer-Specific Technology and/or Development Program Technology.      1.15 " 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 JPT and the JSC and (b) to the extent involving matters that are ARCHEMIX Decisions, approved by ARCHEMIX in accordance with Section 2.1.6.      1.16 " ARCHEMIX Technology " means, collectively, ARCHEMIX Background Technology and ARCHEMIX Program Technology.      1.17 " Calendar Quarter " means each successive period of three (3) consecutive calendar months commencing on January 1, April 1, July 1 or October 1, as the case may be, and ending on March 31, June 30, September 30 or December 31, respectively; provided, that, the initial Calendar Quarter shall commence on the Effective Date and end on March 31, 2007.      1.18 " Calendar Year " means each successive period of twelve (12) months commencing on January 1 and ending on December 31.      1.19 " 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 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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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.      1.20 " Collaboration " means the alliance of ARCHEMIX and MERCK established pursuant to this Agreement for the purposes of identifying, researching and Developing Development Candidates and Commercializing Products in the Field in the Territory.      1.21 " Collaboration Aptamer " means, collectively, Program Oligonucleotides, Program Aptamers, Lead Compounds, Optimized Lead Compounds, Development Candidates and/or Products.      1.22 " 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 Affiliates or sublicensees (or Sublicensees, as the case may be) 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.      1.23 " Commercialization " or " Commercialize " means any and all activities directed to the commercialization of a Product after Commercialization Regulatory Approval has been obtained, including marketing, manufacturing for commercial sale, promoting, detailing, distributing, offering to sell and selling a Product, importing a Product for sale, conducting post-marketing human clinical studies and interacting with Regulatory Authorities regarding the foregoing. When used as a verb, "to Commercialize" and "Commercializing" means to engage in Commercialization and "Commercialized" has a corresponding meaning.      1.24 " 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, if any, or, with respect to activities of ARCHEMIX in the Commercialization of a Waived Compound which is the subject of a transition plan pursuant to Section 7.1.2(c), the efforts and resources comparable to those undertaken by ARCHEMIX in pursuing the research, discovery, development, commercialization and intellectual property protection of proprietary materials and the development of product candidates, 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 MERCK in the Research Program, the Development of a particular Development Candidate or the Commercialization of a particular Product, the efforts and resources comparable to those undertaken by MERCK 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 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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applicable and without limitation, mechanism of action; efficacy and safety; product profile; actual or anticipated Regulatory Authority approved labeling; and 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 alternative products and market conditions; actual or projected profitability and availability of capacity to manufacture and supply for commercial sale).      1.25 " Commercialization Regulatory Approval " means, with respect to any Product, the Regulatory Approval required by Applicable Laws to sell such Product for use in the Field in a country or region in the Territory. "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 the first Indication or sNDA for an additional 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.      1.26 " 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.      1.27 " Competitive Program " means any research, development or commercialization activity that involves an Aptamer that targets a Program Target for use in the Field.      1.28 " Confidential Information " means (a) with respect to ARCHEMIX, all tangible embodiments of ARCHEMIX Technology, (b) with respect to MERCK, all tangible embodiments of MERCK Technology and (c) with respect to each Party, (i) all tangible embodiments of Joint Technology and (ii) all information, Technology and Proprietary Materials disclosed or provided by or on behalf of such Party (the "disclosing Party") to the other Party (the "receiving Party") or to any of the receiving Party’s employees, consultants, Affiliates or sublicensees (or Sublicensees, as the case may be); 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 contemporaneous credible written documentation, other than by virtue of a prior confidential disclosure to such receiving Party; (B) as of the date of disclosure it is in the public domain, or it subsequently enters the public domain through 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 disclosing Party; or (D) it is independently developed by or for the receiving Party without reference to or use of any Confidential Information of the disclosing Party as demonstrated by contemporaneous credible written documentation. For purposes of clarity, unless excluded from Confidential Information pursuant to the proviso at the end of the preceding sentence, any scientific, technical or financial information of a Party that is disclosed at any meeting of the JSC, JPT or JMC or disclosed 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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through an audit report shall constitute Confidential Information of the disclosing Party. Notwithstanding anything herein to the contrary, the terms of this Agreement shall constitute Confidential Information of each Party.      1.29 " 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.      1.30 " 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 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.      1.31 " CTN " means the notification submitted to the Japanese Ministry of Health, Labor and Welfare prior to the Initiation of a clinical trial in Japan.      1.32 " 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).      1.33 " Detail " means, with respect to a Co-Promoted Product, an interactive, live, face-to-face contact of a Representative within the Co-Promotion Territory with a medical professional with prescribing authority or other individuals or entities that have a significant impact or influence on prescribing decisions, in an effort to increase physician prescribing preferences of such Co-Promoted Product for its approved uses within the Co-Promotion Territory. When used as a verb, "Detailing" means performing Details. When used as an adjective, "Detailing" means of or related to performing Details.      1.34 " Development " or " Develop " means, with respect to each Optimized Lead Compound and Development Candidate, all non-clinical and clinical activities performed in order to obtain Regulatory Approval of a Product Derived from such Optimized Lead Compound or Development Candidate in accordance with this Agreement up to and including the obtaining of Commercialization Regulatory Approval of such Product. For purposes of clarity, these activities include, without limitation, in vivo animal efficacy testing, preclinical safety testing, 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. 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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     1.35 " Development Candidate " means any Optimized Lead Compound that the JPT nominates and the JSC accepts as a Development Candidate as set forth in Section 3.7 and for which MERCK has paid the Development Candidate Milestone Payment in the time allotted for such payment in Section 5.4.1; provided, that, no Collaboration Aptamer shall, after [***], be nominated or accepted as a Development Candidate.      1.36 " Development Candidate Milestone Payment " means the payment to be made to ARCHEMIX upon occurrence of Milestone 2 pursuant to Section 5.4.1.      1.37 " Development Candidate Selection Criteria " or " DCSC " means the guideline criteria for selecting Optimized Lead Compounds that are sufficiently promising to warrant further Development as Development Candidates as set forth in Schedule 6 attached hereto, as such Schedule 6 shall be amended from time to time by the JSC, which amendment shall occur before any activities with respect to such Development Candidate are initiated, in any material respect, in the Development Program.      1.38 " Development Program " means the Development activities to be conducted during the Term with respect to each Optimized Lead Compound and Development Candidate pursuant to the Annual Development Plan, with the objective of developing such Optimized Lead Compound or Development Candidate into a Product.      1.39 " Development Program Technology " means any Technology that is first conceived or reduced to practice within the Development Program including but not limited to a process for modifying, optimizing, using, formulating, delivering and/or stabilizing a Collaboration Aptamer.      1.40 " 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.      1.41 " Diagnostic Product " means In Vitro Diagnostics, In Vivo Diagnostic Agents and any product used for Diagnosis. For purposes of clarity, the term Diagnostic Product shall not include a product used for the delay of the onset or progression of, or the treatment or prevention of, an Indication.      1.42 " 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 (including, without limitation, a CTN); and (c) all supplements and amendments to any of the foregoing.      1.43 " 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 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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[***] in the assay by the Program Target and the [***] fraction of the [***] pool is at least [***] relative to the [***] fraction for [***] (i.e., [***]) pool of [***].      1.44 " Effective Date " means the date first set forth above.      1.45 " Excepted Decision " means any of the following decisions requiring the unanimous approval of all members of the JSC: (a) any decision as to whether a milestone has been achieved under this Agreement for which a milestone payment is payable; and (b) any decision as to whether a proposed Target is a [***].      1.46 " Excluded Aptamer " means any Aptamer listed on Schedule 4 attached hereto.      1.47 " Excluded Target " means any Target listed on Schedule 5 attached hereto.      1.48 " Failed Compound " means any Collaboration Aptamer directed against a Failed Target.      1.49 " Failed Target " means (a) any Program Target as to which the JPT concludes and the JSC agrees, that ARCHEMIX is unable or unlikely to identify [***] Program Target, (b) any Program Target for which ARCHEMIX fails to identify [***]; (c) any Program Target for which MERCK discontinues Development of [***], provided, that, at such time no other [***] for such Program Target are in Development, and (d) any Program Target for which [***] meeting the applicable [***] exists and for which MERCK has not [***] the [***] in the time allotted for such [***] in Section 5.4.1. For purposes of clarity, a Failed Target shall not be considered a Program Target.      1.50 " FDA " means the United States Food and Drug Administration or any successor agency or authority thereto.      1.51 " FDCA " means the United States Federal Food, Drug, and Cosmetic Act, as amended.      1.52 " Field " means [***]. For purposes of clarity, the Field shall not include the research, development, manufacture, use or sale of Diagnostic Products or Radio Therapeutics.      1.53 " First Commercial Sale " means, with respect to a Product in a country in the Territory, the first sale, transfer or disposition for value or for an end user of such Product in such country.      1.54 " 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, regulation, ordinance, demand or requirement of any government or of any subdivision, authority or representative of any such government. 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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     1.55 " 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 appropriately trained employees of ARCHEMIX, measured in accordance with ARCHEMIX’s time allocation practices from time to time.      1.56 " FTE Cost " means, for any period, the applicable FTE Rate multiplied by the applicable number of FTEs in such period.      1.57 " FTE Rate " means (a) for the [***] Contract Year, [***] Dollars (US $[***]); (b) for the [***] Contract Year, [***] Dollars (US $[***]); (c) for the [***] Contract Year, [***] Dollars (US $[***]); (d) for each FTE or portion thereof greater than [***] in [***] Contract Year during the Research Program Term, [***] Dollars (US $[***]); and (e) for [***] Contract Year on and after the expiration of the Research Program Term, an amount per Contract Year to be determined by multiplying [***] Dollars (US $[***]) by the [***] in the Consumer Price Index since the Effective Date ([***] for all items; [***]; available at [***] and adding or subtracting the product of such multiplication to or from [***] Dollars (US $[***]). The FTE rate includes all salary, employee benefits, materials and all other expenses including support staff and overhead for or associated with ARCHEMIX scientists performing activities but does not include Third Party Costs as set forth in Section 5.3.3.      1.58 " GAAP " means United States generally accepted accounting principles, consistently applied.      1.59 " Hatch-Waxman Act " means the Drug Price Competition and Patent Term Restoration Act of 1984, as amended.      1.60 " ICC " means the International Chamber of Commerce in Paris, France.      1.61 " 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 Development 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 Development Candidate in humans in such country or region; and (c) all supplements and amendments to any of the foregoing.      1.62 " Indication " means any human indication, disease or condition in the Field, which can be treated, prevented, cured or the progression of which can be delayed. For purposes of clarity, distinctions between human indications, diseases or conditions with respect to a Product shall be made by reference to the World Health Organization International Classification of Diseases, version 10 (as revised and updated, "ICD10").      1.63 " Initiation " means, with respect to a human clinical trial, the first date that a subject or patient is dosed in such clinical trial.      1.64 " 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 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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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).      1.65 " 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.      1.66 " Joint Patent Rights " means Patent Rights that contain one or more claims that cover Joint Technology.      1.67 " Joint Project Team " or " JPT " means the committee composed of ARCHEMIX and MERCK representatives established pursuant to Section 2.2.      1.68 " Joint Steering Committee " or " JSC " means the committee composed of ARCHEMIX and MERCK representatives established pursuant to Section 2.1.      1.69 " Joint Technology " means (a) all Program Generic Technology and (b) any Program Technology other than Program Aptamer-Specific Technology, that is (i) jointly conceived or reduced to practice by employees of or consultants to MERCK and employees of or consultants to ARCHEMIX or (ii) conceived or reduced to practice solely by employees of or consultants to a Party with the use in any material respect of any Technology, Patent Rights or Proprietary Materials of the other Party. For the avoidance of doubt, any Program Technology that relates to the SELEX® Process or to the SELEX® Technology shall not be considered Joint Technology irrespective of which Party conceived or reduced to practice such improvement.      1.70 " Knowledge " means, with respect to a Party, the actual knowledge of any employee of such Party.      1.71 " Lead Compound " means any Program Aptamer that [***] Program Target that is first identified in the conduct of the Research Program or Development Program, or any Aptamer [***] first identified in the conduct of the Research Program or Development Program that [***] Program Target; provided, that, no Collaboration Aptamer shall, after [***], be nominated or designated as a Lead Compound.      1.72 " Licensed Patent Rights " means any ARCHEMIX Patent Rights and ARCHEMIX’s 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 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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or of its use, or (b) are necessary for MERCK to exercise the licenses granted to it pursuant to Sections 7.1 and 7.2. For purposes of clarity, Licensed Patent Rights existing as of the Effective Date include those listed on Schedule 3 attached hereto.      1.73 " Licensed Technology " means any ARCHEMIX Technology and ARCHEMIX’s 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, and (b) is necessary for MERCK to exercise the licenses granted to it pursuant to Sections 7.1 and 7.2.      1.74 " Major Market Country " means each of the [***] and [***].      1.75 " MERCK Background Technology " means any Technology that is used by MERCK, or provided by MERCK for use, in the Research Program and/or Development Program that is (a) Controlled by MERCK as of the Effective Date or (b) conceived or first reduced to practice by employees of, or consultants to, MERCK after the Effective Date other than in the conduct of MERCK Research Activities or MERCK Development Activities and without the use in any material respect of any Collaboration Aptamers, ARCHEMIX Technology, ARCHEMIX Patent Rights, or ARCHEMIX Materials. For purposes of clarity, MERCK Background Technology shall not include MERCK Program Technology or MERCK’s interest in Joint Technology.      1.76 " MERCK Development Activities " means all Development activities specified to be conducted by MERCK in any Annual Development Plan (or amendment thereto).      1.77 " MERCK Materials " means any Proprietary Materials that are Controlled by MERCK and used by MERCK, or provided by MERCK for use, in the Research Program and/or the Development Program.      1.78 " MERCK Patent Rights " means any Patent Rights Controlled by MERCK that contain one or more claims that cover MERCK Technology.      1.79 " MERCK Program Technology " means (a) any Program Technology that (i) is not ARCHEMIX Program Technology or Joint Technology and (ii) is conceived or first reduced to practice by employees of, or consultants to, MERCK, alone or jointly with any Third Party, without the use in any material respect of any ARCHEMIX Technology, ARCHEMIX Patent Rights, ARCHEMIX Materials or Joint Technology; (b) any Program Aptamer-Specific Technology; and (c) any Development Program Technology.      1.80 " MERCK Research Activities " means all activities specified to be conducted by MERCK in any Annual Research Plan (or amendment thereto) that are approved by the JPT and JSC.      1.81 " MERCK Technology " means, collectively, MERCK Background Technology and MERCK Program Technology. 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 " Minimum FTE Funding Commitment " means the funding of at least [***] ARCHEMIX FTEs at the applicable FTE Rate for each Contract Year during the Research Program Term.      1.83 " 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.      1.84 " Net Sales " means the gross amount billed or invoiced by MERCK 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 (a) allowances for normal and customary trade, quantity and cash discounts actually allowed and taken, (b) transportation, insurance and postage charges, if prepaid by MERCK or any Affiliate or Sublicensee of MERCK and included on any such party’s bill or invoice as a separate item, (c) credits, rebates, returns pursuant to agreements (including, without limitation, managed care agreements) or government regulations, to the extent actually allowed, and (d) sales, use and other consumption taxes similarly incurred to the extent included on the bill or invoice as a separate item. In addition, Net Sales are subject to the following: If MERCK 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, 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, "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. 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 or such other reasonable allocation method as the Parties shall agree. 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 a commercially reasonable sampling program, shall not give rise to any Net Sales.      1.85 " Optimized Lead Compound " means any [***] Compound that the JPT nominates and the JSC accepts as meeting the OLSC for such Program Target; provided, that, no [***] shall, after becoming a [***], be nominated or designated as an Optimized Lead Compound.      1.86 " Optimized Lead Compound Selection Criteria " or " OLSC " means the guideline criteria for selecting Lead Compounds that are sufficiently promising to warrant further research as an Optimized Lead Compound as set forth in Schedule 1 attached hereto, as such Schedule 1 may be amended from time to time by the JSC, which amendment shall occur before 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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any research activities are initiated with respect to such Optimized Lead Compound against the applicable Program Target. Notwithstanding anything to the contrary set forth in Schedule 1 , for purposes of determining whether a Lead Compound has been designated as an Optimized Lead Compound for Milestone 1 in Section 5.4.1, [***] shall be required to be performed with respect to such Lead Compound, whether or not included as part of the OLSC.      1.87 " Patent Rights " means the rights and interests in and to 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.      1.88 " Permitted Screening Activities " means, [***] to any [***], any [***] ARCHEMIX [***] to such [***] for [***] and/or for [***] for the [***] of [***] Aptamers [***] bind to a [***] a [***].      1.89 " 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.      1.90 " Phase I Clinical Trial " means a clinical trial conducted 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.      1.91 " Phase II Clinical Trial " means a clinical trial conducted in patients with a particular disease or condition, 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.      1.92 " Phase III Clinical Trial " means a pivotal clinical trial conducted in patients with a particular disease or condition, 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 Development 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.      1.93 " Product " means any pharmaceutical or medicinal item, substance or formulation that contains, incorporates or comprises a Collaboration Aptamer or any Aptamer Derived therefrom that binds a Program Target. Notwithstanding the above, if a first pharmaceutical or medicinal item, substance or formulation is deemed to be a Product for purposes of this Agreement, any subsequent pharmaceutical or medicinal item, substance or formulation will be considered to be an additional Product for purposes of this Agreement only 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 the extent that it is a new chemical entity (as defined by the FDCA) with respect to the existing Product(s).      1.94 " 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.      1.95 " Product Trademark " 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 MERCK and (b) together with all goodwill associated therewith and promotional materials relating thereto.      1.96 " Program Aptamer " means any [***] that is an [***] that [***] and that is first identified in the performance of the Research Program or during Development and/or any [***] that [***] that is [***] from such [***] and that is first identified in the performance of the Research Program or during Development.      1.97 " Program Aptamer-Specific Patent Rights " means all Patent Rights that cover only Program Aptamer-Specific Technology.      1.98 " Program Aptamer-Specific Technology " means any Program Technology that relates specifically to (a) any Collaboration Aptamer or (b) the manufacture, formulation, delivery, production or use of a Collaboration Aptamer.      1.99 " Program Generic Patent Rights " means Patent Rights that cover only Program Generic Technology.      1.100 " Program Generic Technology " means any Program Technology that relates generally to the manufacture, formulation, delivery, production or use of Aptamers.      1.101 " Program Oligonucleotide " means the [***] and [***] obtained from an [***] and [***] and [***] in the performance of the [***] against a [***] that is not a [***].      1.102 " Program Target " means the Targets listed on Schedule 2A attached hereto, as amended from time to time in accordance with Section 3.5.      1.103 " 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 conceived or first reduced to practice (actively or constructively) by either Party in the conduct of the Research Program.      1.104 " 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 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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or (b) that are otherwise conceived or reduced to practice in the conduct of the Research Program or the Development Program.      1.105 " Quarterly FTE Payment " means the minimum amount payable by MERCK to ARCHEMIX for FTEs during each Calendar Quarter of the Research Program Term pursuant to Section 5.3, which shall equal the greater of: (a) $[***] per Calendar Quarter in the [***] Contract Year, $[***] per Calendar Quarter in the [***] Contract Year, and $[***] per Calendar Quarter in the [***] Contract Year; or (b) the estimated FTE Cost as set forth in the Annual Research Plan for such Calendar Quarter.      1.106 " 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.      1.107 " Regulatory Approval " means, with respect to any country or region in the Territory, any approval, product and establishment license, registration or authorization of any Regulatory Authority required for the manufacture, use, storage, importation, exportation, distribution, transport or sale of a Product for use in the Field in such country or region.      1.108 " 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.      1.109 " Regulatory Filings " means, collectively: (a) all INDs, establishment 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 and 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.      1.110 " Representative " means an individual (including a medical service liaison, sales representative or other representative) employed and trained by either Party or employed by a Third Party or self-employed and trained by or on behalf of a Party, in any case, to Detail a Co-Promoted Product.      1.111 " Research Program " means the research program to be conducted by the Parties during the Research Program Term pursuant to the Annual Research Plan up to and including the selection of Optimized Lead Compounds from Lead Compounds. For purposes of clarity, the 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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Research Program does not include any Development activities performed in the course of the Development Program.      1.112 " Research Program Term " means the period beginning on the Effective Date and ending on the last day of the third Contract Year; provided, that, if this Agreement is terminated prior to the end of the Research Program Term, the effective date of such early termination shall become the last day of the Research Program Term.      1.113 " Royalty Term " means, on a Product-by-Product and country-by-country basis, the period beginning on the date of First Commercial Sale of a Product in a country and ending on the later to occur of (a) expiration of the last to expire Valid Claim of the Licensed Patent Rights, Program Aptamer-Specific Patent Rights or Joint Patent Rights in such country that covers such Product or its identification, manufacture, use, import, offer for sale or sale or (b) (i) with regard to the first Product for each Program Target sold in such country, fifteen (15) years from the date of the First Commercial Sale of such first Product in such country or (ii) with regard to each additional Product for such Program Target sold in such country, ten (10) years from the date of the First Commercial Sale of each such additional Product in such country.      1.114 " SELEX® Portfolio " means those Patent Rights licensed by Gilead to ARCHEMIX pursuant to the ARCHEMIX-Gilead License Agreement.      1.115 " SELEX® 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 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.      1.116 " SELEX® Technology " means (a) generic aptamer compositions and (b) any process for modifying, optimizing and/or stabilizing an aptamer wherein such modification, optimization or stabilization includes, without limitation minimization, truncation, conjugation, pegylation, complexation, substitution, deletion and/or incorporation of modified nucleotides.      1.117 " sNDA " means a Supplemental New Drug Application, as defined in the FDCA and applicable regulations promulgated thereunder.      1.118 " Sublicense Agreement " means any agreement entered into by MERCK with a Sublicensee.      1.119 " Sublicensee " means any Third Party to which MERCK grants a sublicense under the licenses granted to it under Section 7.1 or 7.2.      1.120 " Supplemental Product " means a product having independent, supplementary or enabling therapeutic effect (e.g., as a catalyst or adjuvant) or diagnostic utility. 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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     1.121 " Target " means a protein, cytokine, enzyme, receptor, transducer, transcription factor, antigen or any other non-nucleic acid molecule.      1.122 " Target Replacement List " means the list of Targets on Schedule 2B attached hereto, as amended pursuant to Section 3.5.1.      1.123 " Target Selection Field " means the treatment or prevention in humans of cancer.      1.124 " 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).      1.125 " Terminated Compounds " means (a) all Collaboration Aptamers upon any termination of this Agreement by ARCHEMIX pursuant to Section 10.2.3 or Section 10.2.2 or by MERCK pursuant to Section 10.2.1; and (b) the relevant Collaboration Aptamers binding specifically to the Program Target for which MERCK’s license is terminated by ARCHEMIX pursuant to Section 10.2.2 due to failure of MERCK to meet its diligence obligations, as provided in Section 10.4.      1.126 " Territory " means all countries and territories of the world.      1.127 " Third Party " means a Person other than MERCK and ARCHEMIX and their respective Affiliates.      1.128 " 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.      1.129 " UTC " means University Technology Corporation, the successor to the University Research Corporation.      1.130 " Valid Claim " means any claim of a pending patent application or an issued unexpired patent that (a) has not been finally cancelled, withdrawn, abandoned or rejected by any 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.      1.131 " Waived Compound " means any Collaboration Aptamer directed against a Waived Target.      1.132 " Waived Target " means (a) any Program Target for which MERCK, in its sole discretion, discontinues Development of a Development Candidate; provided, that, no other 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 Candidates for such Program Target are in Development at such time and (b) any Program Target which MERCK designates as a Waived Target in writing to ARCHEMIX.       Additional Definitions . In addition, each of the following definitions shall have the respective meanings set forth in the section of this Agreement indicated below:

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 Steering Committee .           2.1.1 Establishment . Within [***] days from the Effective Date, ARCHEMIX and MERCK shall establish the Joint Steering Committee. Unless otherwise agreed by the Parties, the term for the JSC shall commence as of the Effective Date and continue until the last day of the Research Program Term ("JSC Term"); provided, that, the JSC Term shall be extended in the event that, and for so long as, the JPT Term is extended or any Co-Promoted Products are being Commercialized. The JSC shall have and perform the responsibilities set forth in Section 2.1.4.           2.1.2 Membership. Upon establishment of the JSC, each Party shall designate in writing, in its sole discretion, [***] members to the JSC, which shall be members of its management. Unless otherwise agreed by the Parties, one of MERCK’s designees shall be designated by MERCK 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 JSC, by giving written notice to the other Party. Initial designees of the Parties to the JSC shall be designated by each Party by written notice to the other Party as soon as is reasonably practicable following the Effective Date.           2.1.3 Meetings .                (a)  Schedule of Meetings; Agenda . The JSC shall establish a schedule of times for regular meetings, taking into account the planning needs of the Collaboration and its responsibilities. In urgent cases, special meetings of the JSC 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 JSC meet less frequently than once in each Calendar Year. Regular and special meetings of the JSC 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 JSC member an agenda for each JSC meeting not later than one (1) week prior to such meeting.                (b)  Quorum; Voting; Decisions . At each JSC meeting (i) the presence in person of at least [***] [***] 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 JSC at such meeting. All decisions of the JSC shall be made by unanimous vote. Alternatively, the JSC may act by written consent signed by at least [***] [***] designated by each Party subject to Section 2.1.6. Whenever any action by the JSC is called for hereunder during a time period in which the JSC is not scheduled to meet, the Chair shall cause the JSC 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 JSC may attend 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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JSC meetings as non-voting observers with the consent of the other Party, which shall not be unreasonably withheld, conditioned or delayed.                (c)  Minutes . The JSC 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 JSC 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 JSC shall have the opportunity to provide comments on the draft minutes. The minutes shall be approved, disapproved and revised as necessary at the next JSC 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 JSC by the Chair.           2.1.4 Responsibilities . The JSC shall be responsible for overseeing the conduct and progress of the Research Program and the Development of Optimized Lead Compounds and Development Candidates for which ARCHEMIX is performing Development activities. Without limiting the generality of the foregoing, the JSC shall have the following responsibilities:                (a) overseeing the JPT’s performance of its responsibilities;                (b) reviewing and approving each Annual Research Plan and each Annual Development Plan under which ARCHEMIX is responsible for performing Development activities;                (c) reviewing and approving any amendment to an Annual Research Plan approved by the JPT and submitted to it for its approval;                (d) reviewing and approving any amendment to an Annual Development Plan under which ARCHEMIX is responsible for performing Development activities approved by the JPT and submitted to it for its approval;                (e) reviewing data, reports or other information submitted to it by the JPT from time to time;                (f) resolving all JPT matters that are in dispute;                (g) reviewing and either approving or rejecting any decision of the JPT to nominate any Lead Compound as an Optimized Lead Compound or any decision of the JPT to nominate any Optimized Lead Compound as a Development Candidate;                (h) resolving any dispute as to whether a milestone event under this Agreement has occurred; and                (i) implementing a mutually acceptable mechanism for reporting Adverse Events between the Parties for each Development Candidate and Product; and 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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               (j) making such other decisions as may be delegated to the JSC pursuant to this Agreement or by mutual written agreement of the Parties after the Effective Date.           2.1.5 Interests of the Parties . Notwithstanding any other provisions of this Agreement, all decisions made and all actions taken by the JSC shall be made or taken in the best interest of the Collaboration.           2.1.6 Dispute Resolution . The JSC members shall use reasonable efforts to reach agreement on any and all matters. Such reasonable efforts shall, if requested by any member of the JSC, include the engagement of a mutually acceptable Person who is not affiliated with either Party and has particular experience or expertise with respect to a particular matter to advise the JSC, the expense of any such Person to be borne equally by the Parties. In the event that, despite such reasonable efforts, agreement on a particular matter cannot be reached by the JSC within thirty (30) days after the JSC first meets to consider such matter (each such matter, a "Disputed Matter"), then, if the Disputed Matter does not involve an Excepted Decision or an ARCHEMIX Decision, and except as set forth in the last sentence of this section, MERCK shall have the right to make the final decision on such Disputed Matter, but shall only exercise such right in good faith after full 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 after full consideration of the positions of both Parties and (ii) if the Disputed Matter involves an Excepted Decision, (A) the Chair of the JSC shall refer such Disputed Matter to the President of ARCHEMIX and the head of pre-clinical R&D of MERCK (the "Designated Senior Officers"), who shall promptly initiate discussions in good faith to resolve such Disputed Matter and (B) if such Disputed Matter is not resolved by the Designated Senior Officers within ten (10) days after the date the Designated Senior Officers first met to consider such Disputed Matter or forty-five (45) days after the date the JSC first met to consider such Disputed Matter, the Disputed Matter shall be resolved in accordance with Section 13.1. For purposes of clarity, under no circumstances shall the determination of whether MERCK or ARCHEMIX has used or is using Commercially Reasonable Efforts be submitted for resolution under this Section 2.1.6.      2.2 Joint Project Team .           2.2.1 Establishment . Within [***] days from the Effective Date, ARCHEMIX and MERCK shall establish the Joint Project Team. Unless otherwise agreed by the Parties, the term for the JPT shall commence as of the Effective Date and continue until the last day of the Research Program Term ("JPT Term"); provided, that, the JPT Term shall be extended in the event that, and for so long as, ARCHEMIX has obligations to perform ARCHEMIX Development Activities. The JPT shall have and perform the responsibilities set forth in Section 2.2.4.           2.2.2 Membership . Upon establishment of the JPT, each Party shall designate in writing, in its sole discretion, [***] members to the JPT (which members shall be employees of such Party). Unless otherwise agreed by the Parties, one of ARCHEMIX’s designees shall be designated by ARCHEMIX as the Chair of the JPT; provided, that, to the extent the JPT Term is 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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extended as provided in Section 2.2.1 beyond the Research Program Term, MERCK shall have the right to designate one of MERCK’s designees 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 designated by each Party by written notice to the other Party as soon as is reasonably practicable following the Effective Date.           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 [***] during the JPT Term taking into account, without limitation, the planning needs of the Research Program and its responsibilities. In urgent cases 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 of the JPT shall prepare and circulate to each JPT member an agenda for each JPT meeting no later than one (1) week 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 of the JPT 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 JSC for decision, and, in case the JSC is unable to resolve the matter, it shall be resolved in accordance with Section 2.1.6.                (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 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 of the JPT 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, final minutes of each meeting shall be circulated to the members of the JPT by the chair of the JPT. 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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          2.2.4 Responsibilities . The JPT shall be responsible for (a) overseeing the conduct and progress of the Research Program, the recommendation of Optimized Lead Compounds and the recommendation of Development Candidates for which ARCHEMIX is responsible for performing Development activities; and (b) overseeing the Development of Optimized Lead Compounds and Development Candidates for which, and the conduct and progress of each Development Program under which, ARCHEMIX is responsible for performing Development activities. Without limiting the generality of the foregoing, the JPT shall have the following responsibilities:                (a) preparing or directing the preparation of, approving, and recommending to the JSC for its approval all Annual Research Plans;                (b) preparing or directing the preparation of and approving amendments to JSC-approved Annual Research Plans as it deems appropriate in furtherance of the objectives of the Research Program as set forth in the Research Plan and, if any member of the JPT asserts that any such JPT-approved amendment would change the objectives of such Annual Research Plan, submitting such amendment to the JSC 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;                (f) preparing for the JSC on at least a semi-annual basis a progress report for the Research Program in reasonable detail and providing to the JSC such additional information as it may request;                (g) recommending amendments to the OLSC and/or DCSC as it deems appropriate in furtherance of the objectives of the Research Program or Development Program, as applicable, as set forth in the Research Plan or Development Plan, as applicable;                (h) nominating Lead Compounds as Optimized Lead Compounds for acceptance by the JSC;                (i) nominating Optimized Lead Compounds for which ARCHEMIX is responsible for performing Development activities as Development Candidates for acceptance by the JSC;                (j) preparing or directing the preparation of, approving, and recommending to the JSC for its approval all Annual Development Plans under which ARCHEMIX is responsible for performing Development activities; 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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               (k) preparing or directing the preparation of and approving amendments to JSC-approved Annual Development Plans under which ARCHEMIX is responsible for performing Development activities, as it deems appropriate in furtherance of the Development of Development Candidates and, if any member of the JPT asserts that any such JPT-approved amendment would change the objectives of that Annual Development Plan, submitting such amendment to the JSC for its consideration;                (l) monitoring the progress of the Development of each Development Candidate for which ARCHEMIX is performing Development activities, in accordance with, and of each Party’s activities under, the applicable Annual Development Plan;                (m) providing a forum for consensual decision making with respect to the Development Program under which ARCHEMIX is responsible for performing Development activities;                (n) reviewing data, reports or other information submitted by either Party with respect to work conducted in the Development Program under which ARCHEMIX is responsible for performing Development activities;                (o) preparing for the JSC on at least a semi-annual basis a progress report for the Development Program under which ARCHEMIX is responsible for performing Development activities, in reasonable detail and providing to the JSC such additional information as it may request;                (p) making any other decisions as may be delegated to the JPT pursuant to this Agreement or by mutual written agreement of the Parties after the Effective Date and performing such activities as may 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.           2.2.6 Alliance Management . Within [***] days of the Effective Date, each Party shall appoint a person who shall oversee contact between the Parties for all matters related to the Collaboration between meetings of the JSC 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. 3. RESEARCH PROGRAM      3.1 Implementation of the Research Program . The objectives of the Research Program shall be the identification of Lead Compounds for nomination by the JPT to the JSC for approval as Optimized Lead Compounds pursuant to this Agreement. Except for the MERCK Research Activities, if any, which shall be conducted by MERCK at its sole expense, ARCHEMIX shall have the primary right and responsibility to conduct the Research Program. 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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     3.2 Annual Research Plans .           3.2.1 Research Plan . 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 and submitted to, and approved by, the JSC 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 JSC for its approval. The JPT shall manage the preparation of each Annual Research Plan in a manner designed to obtain JSC 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 OLSC and any other criteria that the JPT will utilize to evaluate the results of the Research Program to nominate Optimized Lead Compounds, (iv) the Party that shall be responsible for performing such activities, (v) a timeline and budget for such activities (including Third Party expenses to be incurred for outsourced studies managed by ARCHEMIX), and (vi) with respect to ARCHEMIX Research Activities, the number of FTEs estimated to be required to perform 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 Lead Compounds or to determine whether Lead Compounds should be nominated to the JSC as Optimized Lead Compounds. Any Annual Research Plan may be amended from time to time by the JPT pursuant to Section 2.2.4 or by the JSC pursuant to 2.1.4. Each amendment, modification and update to the Annual Research Plan shall include the resulting changes to the budget, including the number of FTEs to be utilized by ARCHEMIX, shall be set forth in a written document prepared by, or at the direction of, the JPT and approved by the JSC, 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 JSC at which such amendment, modification or update was approved by the JSC. Without limiting the nature or frequency of any other amendments, modifications or updates to the Research Plan that may be approved by the JSC, 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 applicable Contract Year during the Research Program Term in conducting the Research Program pursuant to this Agreement.           3.2.2 Minimum FTEs . MERCK shall request and fund a minimum of [***] FTEs per Contract Year during the three (3) year Research Program Term. MERCK shall have the right to increase the number of FTEs to be provided by ARCHEMIX for any Contract Year; provided, that, (a) any increase above [***] FTEs for any Contract Year shall be subject to MERCK’s notice obligation under Section 3.3.2(c) and (b) any increase, at MERCK’s request, above [***] FTEs for any Contract Year shall be an ARCHEMIX Decision.      3.3 Conduct of Research Program . 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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          3.3.1 ARCHEMIX Responsibilities . During the Research Program Term, ARCHEMIX shall use Commercially Reasonable Efforts to conduct the ARCHEMIX Research Activities using the number of FTEs set forth in the Annual Research Plan.           3.3.2 MERCK Responsibilities . During the Research Program Term, MERCK shall: (a) pay ARCHEMIX the Minimum Quarterly FTE Payment in accordance with Section 5.3; (b) pay ARCHEMIX the applicable FTE Rate per FTE per Contract Year for FTEs greater than [***] in accordance with Section 5.3.1; (c) give ARCHEMIX not less than [***] days’ written notice in the event that MERCK requires a number of FTEs above [***] FTEs in any Contract Year; (d) commit such resources as are reasonably necessary to conduct the MERCK Research Activities set forth in the Annual Research Plan; and (e) use Commercially Reasonable Efforts to conduct the MERCK Research Activities, if any, set forth in the Annual Research Plan.           3.3.3 Compliance and Funding . Each Party shall perform its obligations under each Annual Research Plan 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 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 and benefits of its employees.           3.3.4 Cooperation . Scientists at ARCHEMIX and MERCK 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 for the other Party to perform its obligations under any Annual Research Plan.      3.4 Records .           3.4.1 Record Keeping .                (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 review such records to the extent reasonably required for such other Party’s performance of its obligations under this Agreement; provided, that, the non-reviewing Party may redact information not relevant to the Research Program prior to such review. Notwithstanding the foregoing, MERCK shall not have the right to review any records that relate to any Failed Compounds, Waived Compounds or Terminated Compounds. 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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               (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 Lead Compounds and provide the JPT with any supporting data applicable to such Lead Compounds, (c) 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 OLSC and should be proposed to the JSC as an Optimized Lead Compound, (d) provide the JPT with the results of activities conducted in the Development Program, if any, with respect to each Optimized Lead Compound so as to enable the JPT to determine whether such Optimized Lead Compound meets the DCSC and should be proposed to the JSC as a Development Candidate, (e) provide the JPT with such additional information that it has in its possession as may be reasonably requested from time to time by the JPT, and (f) provide MERCK, on or before [***] days from the termination or expiration of the Research Program Term, with a final report regarding all ARCHEMIX Research Activities conducted by ARCHEMIX during the Research Program Term to the extent not previously included in the reports described above. MERCK shall (i) provide the JPT, at least once per [***], with reports in reasonable detail regarding the status of all MERCK Research Activities and such additional information that it has in its possession as may be reasonably requested from time to time by the JPT, (ii) provide the JPT with the results of activities conducted in the Development Program under which ARCHEMIX is responsible for performing Development activities with respect to each Optimized Lead Compound so as to enable the JPT to determine whether such Optimized Lead Compound meets the DCSC and should be proposed to the JSC as a Development Candidate, and (iii) provide ARCHEMIX, on or before [***] days from the termination or expiration of the Research Program Term, with a final report regarding all MERCK Research Activities conducted by MERCK during the Research Program Term to the extent not previously included in the reports described above.      3.5 Selection of Program Targets .           3.5.1 Selection of Program Targets .                (a)  Initial Program Targets . The Parties hereby acknowledge and agree that one (1) Program Target, as set forth on Schedule 2A , has been so designated by the Parties as of the Effective Date. MERCK shall provide written notice of a second Program Target to ARCHEMIX within [***] weeks of the Effective Date. ARCHEMIX shall accept or reject the proposed Target as specified under 3.5.1.d) for the inclusion of a Target into the Research Program.                (b)  Target Replacement List . The Parties hereby acknowledge and agree that two (2) Targets, as set forth on the Target Replacement List on Schedule 2B , have 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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been designated by the Parties as replacement Targets as of the Effective Date. MERCK shall have the right to request that a Target on the Target Replacement List be replaced (a) [***] and (b) [***]. During the first [***] Contract Years of the Research Program Term, ARCHEMIX will inform MERCK in writing, if it intends to commence negotiations with a Third Party with respect to a license, collaboration or similar agreement relating to Aptamers against a Target on the Target Replacement List.                (c)  Replacement of Program Targets . If at any time during the first [***] Contract Years of the Research Program Term, the JSC agrees that a Program Target is unlikely to produce an [***] or [***], then (i) all activities under the Research Program with respect to such Program Target shall cease; (ii) such Program Target shall thereafter be deemed to be a Failed Target; and (iii) MERCK shall have the right to replace such Failed Target with a Target from the Target Replacement List in accordance with Section 3.5.1(d). In addition, MERCK shall have the right at any time during the first [***] Contract Years of the Research Program Term to replace a Program Target with a Target from the Target Replacement List in accordance with Section 3.5.1(d) if: (i) MERCK reasonably believes based on published literature or proprietary data first available after the designation of a Target as a Program Target that such Program Target is [***] for use in the Target Selection Field; or (ii) MERCK reasonably determines that it is legally necessary to obtain a license or other right, title or interest in and to an issued patent that had not issued and/or had not been published as a pending application at the time a Target was designated as a Program Target in order to successfully research, Develop and Commercialize a Product that binds such Program Target. Notwithstanding anything to the contrary herein, any Program Target replaced in accordance with the preceding sentence of this Section 3.5.1(c) shall be deemed a Failed Target. A Target proposed by MERCK for inclusion in the Research Program which is not on the Target Replacement List may be rejected by ARCHEMIX for any reason, in its sole discretion.                (d)  Replacement of Targets . To the extent MERCK has the right to propose that a Target be added to the Target Replacement List as described in Section 3.5.1(b) or that a Failed Target be replaced by a Target from the Target Replacement List as described in Section 3.5.1(c), MERCK shall provide written notice to ARCHEMIX. ARCHEMIX shall accept or reject the proposed Target within [***] days after receipt of such notice from MERCK. A Target proposed by MERCK for inclusion on the Target Replacement List or in the Research Program shall only be rejected by ARCHEMIX if prior to MERCK’s notice: (A) it is an [***], (B) ARCHEMIX is prohibited by an executed contract from licensing Aptamers against such proposed Target or its natural ligand(s), to MERCK, (C) 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 or its natural ligand(s), or (D) ARCHEMIX is developing, for its own benefit, Aptamers against such Target or its natural ligand(s) under a bona fide internal development program against such Target, has adopted a research plan for such Target or its natural ligand, or has formally designated such Target or its natural ligand(s) for research. In addition to the reasons specified in the foregoing clauses (A)-(D), ARCHEMIX also may reject a Target proposed by MERCK for inclusion on the Target Replacement List if such Target does not fall within the Target Selection Field. ARCHEMIX shall give MERCK prompt written notice during the Research Program Term if any of the restrictions on any Target that is rejected by ARCHEMIX pursuant to the foregoing clause (A), (B), (C) or (D) lapse, or are 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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otherwise terminated, such that the previously rejected Target becomes eligible for inclusion as a Program Target or for inclusion on the Target Replacement List.                (e)  Obligations of JPT . As promptly as practicable after designation of a new Program Target in accordance with Section 3.5.1(d), the JPT shall (i) develop and submit to the JSC for its approval the OLSC and DCSC for such new Program Target and (ii) prepare an update to the Annual Research Plan to include the ARCHEMIX Research Activities to be conducted to identify Lead Compounds against such new Program Target for potential nomination as an Optimized Lead Compound.           3.5.2 Termination of Replacement Right . Notwithstanding anything to the contrary in this Agreement, MERCK’s right to add Targets to the Target Replacement List pursuant to Section 3.5.1(b) and/or replace Program Targets pursuant to Section 3.5.1(c) shall terminate on the [***] of the [***] Contract Year. 3.6 Identification of Lead Compounds and Optimized Lead Compounds .           3.6.1 Lead Compounds . ARCHEMIX shall use Commercially Reasonable Efforts in good faith to perform the SELEX® Process to identify Lead Compounds in accordance with each Annual Research Plan, as amended.           3.6.2 Optimized Lead Compounds . Within [***] days after its receipt of each report from ARCHEMIX pursuant to Section 3.4.2 identifying a Lead Compound as meeting the applicable OLSC (or which either Party reasonably believes should be an Optimized Lead Compound), the JPT shall review the data and information and determine whether to nominate the Lead Compound to the JSC for designation as an Optimized Lead Compound. If the JPT elects to nominate any such Lead Compound as an Optimized Lead Compound, the JPT shall promptly furnish all available information to the JSC. The JSC shall consider such nomination within [***] days, and if the JSC approves the nomination of the Lead Compound, such Lead Compound shall be deemed to be an Optimized Lead Compound for purposes of this Agreement.      3.7 Development Candidates . Within [***] days after either Party reasonably concludes based upon available project reports that an Optimized Lead Compound meets the applicable DCSC, the JPT shall review the data and information and determine whether to nominate the Optimized Lead Compound for designation as a Development Candidate. If the JPT elects to nominate any such Optimized Lead Compound as a Development Candidate, the JPT shall promptly furnish all available information to the JSC. The JSC shall consider such nomination within [***] days so as to enable MERCK to determine whether or not continue Development of such compound, and if the Optimized Lead Compound meets the DCSC and MERCK accepts such Optimized Lead Compound for further Development, such Optimized Lead Compound shall be deemed to be a Development Candidate for purposes of this Agreement.      3.8 MERCK Decision Not to Go Forward . MERCK has the right to determine in [***] not to continue the Development and Commercialization of a Development Candidate against a specific Program Target. 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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     3.9 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 of the Transferring Party for use in the Research Program. In connection therewith, each Recipient Party hereby agrees that (a) it shall not use such Proprietary Materials for any purpose other than exercising its rights or performing its obligations under this Agreement; (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 by this Agreement; (d) the Recipient Party shall not acquire any right, title or interest in or to such Proprietary Materials 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.      3.10 Research Program Term . The Research Program shall commence on the Effective Date and shall continue until the last day of the 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 selection and Development of Development Candidates to enable the Commercialization of Products in the Field in the Territory.      4.2 Responsibility for Development of Development Candidates and Commercialization of Products . Except for the ARCHEMIX Development Activities, if any, MERCK shall have [***], for all aspects of the Development of Optimized Lead Compounds and Development 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 Field in the Territory, including, without limitation, the conduct of: (a) all IND-enabling non-clinical studies that are outside of the Research Program; (b) all activities related to human clinical trials (including, without limitation, Phase I Clinical Trials, Phase II Clinical Trials and Phase III Clinical Trials); (c) all activities relating to the manufacture and supply of Development Candidates and Products (including all required process development and scale up work with respect thereto); and (d) all pre-marketing, marketing, promotion, sales, distribution, import and export activities (including securing reimbursement, conducting sales and marketing activities and any post-marketing trials or post-marketing safety surveillance and maintaining databases), subject in each case to Section 4.9.2. Without limiting the generality of the foregoing, MERCK shall have [***], (i) to make all Regulatory Filings for Development Candidates and Products and file all Drug Approval Applications and otherwise seek all Regulatory Approvals for Products, as well as to conduct all correspondence and communications with Regulatory Authorities regarding such matters, subject in each case to Section 4.9.2, and (ii) to report all Adverse Events to Regulatory Authorities if and to the extent required by Applicable Laws. All Regulatory Approvals for Products shall be owned by MERCK, subject to Section 10.3. 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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     4.3 Annual Development Plans . The initial Annual Development Plan shall be prepared by MERCK and submitted to the JSC for its review within [***] days of the date on which the JSC approves the selection of an Optimized Lead Compound and in any event, on or prior to the initiation of Development activities with respect thereto, which shall describe the Development activities to be conducted for the balance of the Contract Year. Thereafter, for each Contract Year during the Term, an Annual Development Plan for each Optimized Lead Compound and Development Candidate shall be prepared by MERCK and provided to the JSC for its review and MERCK shall consult with the JSC with respect to all significant Development decisions to be made with respect to such Annual Development Plan. Each Annual Development Plan shall: (a) set forth (i) the Development objectives, activities, and timelines for the Contract Year covered by the Annual Development Plan with reasonable specificity, (ii) which activities, if any, are ARCHEMIX Development Activities; provided, that, ARCHEMIX has agreed to perform such 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. Any Annual Development Plan may be amended from time to time by MERCK. Without limiting the nature or frequency of any other amendments, modifications or updates to the Annual Development Plan, the Annual Development Plan shall be updated at least once prior to the end of each Contract Year to describe the Development activities to be carried out by each Party during the applicable Contract Year in conducting the Development Program pursuant to this Agreement. Notwithstanding the above, the preparation and management of the Annual Development Plan by the JPT and JSC approval is only required for any Annual Development Plan or amendment thereto under which ARCHEMIX is responsible for performing any Development activities.      4.4 Product Commercialization Plans . Within [***] days after the Initiation of a Phase III Clinical Trial with respect to each Development Candidate, MERCK shall prepare and provide to the JSC for its review a Product Commercialization Plan for each Product Derived from such Development Candidate, and shall inform the JSC with respect to all significant Commercialization decisions to be made with respect to such Product.      4.5 Development and Commercialization Diligence .                (a)  Diligence Obligations . MERCK shall exercise Commercially Reasonable Efforts during the Term to conduct the MERCK Development Activities, to Develop [***] Development Candidate targeted at [***] Program Target and to Commercialize [***] Product targeted at [***] Program Target in the Field in the Territory.                (b)  Effect of Breach of Diligence Obligations . If ARCHEMIX at any time believes that MERCK, on a country-by-country and Product-by-Product basis, is not meeting its diligence obligations pursuant to subsection (a) above, ARCHEMIX may give written notice to MERCK requesting written justification, in the form of detailed reasons that would support the proposition that MERCK is meeting such diligence obligation. In such event, MERCK shall provide such written justification to ARCHEMIX within [***] days after such 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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notice is given. In the event that ARCHEMIX does not receive such justification within such [***] day period or does not agree with such justification, then ARCHEMIX shall have the right, in its sole discretion, on a country-by-country and Product-by-Product basis, to terminate MERCK’s rights with respect to such Target, Development Candidate or Product, and the Collaboration Aptamers against such Target pursuant to Section 10.4 (but leaving unaffected MERCK’s rights under this Agreement to any other Target and Collaboration Aptamer directed against such Target).      4.6 Compliance . Each Party shall perform its obligations under each Annual Development Plan in good scientific manner 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 conducting its activities under Annual Development Plans.      4.7 Cooperation . Scientists at ARCHEMIX and MERCK 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.      4.8 Exchange of Reports; Information; Updates .           4.8.1 Development Program Reports . MERCK shall keep the JSC regularly informed of the progress of its efforts to Develop Development Candidates in the Field in the Territory. Without limiting the generality of the foregoing, MERCK shall, at least once each [***], provide the JSC 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 under the Development Program; provided, that, for so long as ARCHEMIX is obligated to perform ARCHEMIX Development Activities, (a) MERCK shall provide the JSC with the reports described above at least once each [***] and (b) ARCHEMIX and MERCK shall, not less than once each [***], provide the JSC with reports in reasonable detail regarding the status of all Development Activities and such additional information that they have in their possession as may be reasonably requested from time to time by the JSC.           4.8.2 Commercialization Reports . MERCK shall keep the JSC and ARCHEMIX regularly informed of the progress of MERCK’s efforts to Commercialize Products in the Field in the Territory through periodic updates. Without limiting the generality of the foregoing, MERCK shall provide the JSC and ARCHEMIX with [***] written updates to each Product Commercialization Plan, which shall (a) summarize MERCK’s efforts to Commercialize 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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Products, (b) identify the Regulatory Filings and Drug Approval Applications with respect to such Product that MERCK 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) summarize all clinical and other data generated by MERCK with respect to Products. In addition, MERCK shall provide such additional information that it has in its possession as may be reasonably requested by ARCHEMIX regarding the Commercialization of any Product, which request shall not be made more than once each Calendar Year.           4.8.3 Adverse Event Reports; Review of Regulatory Filings and Correspondence .                (a)  Adverse Events . In addition to the updates described in Section 4.8.1 and 4.8.2, MERCK shall provide ARCHEMIX with all Adverse Event information and product complaint information relating to Development Candidates or Products as such information is compiled or prepared by MERCK in the normal course of business in connection with the Development of any Development Candidates or Commercialization of any Product and, in any event, within time frames consistent with reporting obligations under Applicable Laws. MERCK shall provide such Adverse Event and product complaint information hereunder to ARCHEMIX in accordance with Section 13.3. ARCHEMIX may provide all such Adverse Event information to other licensees of ARCHEMIX who have the right to sell Aptamers for therapeutic purposes under a license from ARCHEMIX; provided, that, such other licensees agree to maintain the confidentiality thereof. ARCHEMIX will provide to MERCK Adverse Event information obtained from other licensees of ARCHEMIX who have the right to develop and sell Aptamers for therapeutic purposes under a license from ARCHEMIX; provided, that, such other licensees agree to share such information and MERCK agrees to maintain the confidentiality thereof.                (b)  Preparation of Drug Approval Applications . MERCK shall (i) consult with ARCHEMIX in good faith in the preparation of all Drug Approval Applications for Products in the United States, Japan and in the European Union and (ii) consider all comments of ARCHEMIX in good faith, taking into account the best interests of the Collaboration and of the Development of the applicable Development Candidate and Commercialization of the applicable Product on a global basis.                (c)  Meeting Attendance and Information . MERCK shall 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 Development Candidate or Product, (i) prior to the acceptance of an IND with respect to each Development Candidate or Product and (ii) after acceptance of an IND with respect to each Development Candidate or Product if the subject matter of the meeting shall include any milestone event applicable to such Development Candidate or Product. Upon written request ARCHEMIX may send one person [***] to participate as an observer in such meeting [***]; provided, that, (A) MERCK approves such ARCHEMIX request for any such meetings occurring after acceptance of the IND and (B) to the extent MERCK’s approval is required, MERCK shall [***] any such request of ARCHEMIX. 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 regard to any meeting with the FDA or other Regulatory Authority regarding a Drug Approval Application relating to, or Regulatory Approval for, any Development Candidate or Product, to which ARCHEMIX did not send a representative as provided in this Section 4.8.3(c), MERCK will provide ARCHEMIX with a written summary of information communicated and received thereat.                (d)  Right to Review . Notwithstanding anything to the contrary in this Section 4.8.3, ARCHEMIX shall have the right, upon written notice, to review all such Regulatory Filings and correspondence at MERCK’s office at ARCHEMIX’s sole expense.      4.9 Development and Commercialization Rights and Restrictions .           4.9.1 Development and Commercialization Rights in the Field . Except as provided in this Section 4.9, MERCK shall have the [***] during the Term to Develop Development Candidates and Commercialize Products in the Territory for use in the Field.           4.9.2 Co-Promotion .                (a)  Negotiation of a Potential Co-Promotion Agreement . Within thirty (30) days from filing the NDA for a Product, ARCHEMIX shall provide MERCK with (i) a written notice indicating ARCHEMIX’ interest in the promotion and Detailing of such Product in the United States of America and its territories and possessions jointly with MERCK using a coordinated sales force consisting of Representatives of both Parties ("Co-Promote" or "Co-Promotion") and (ii) a business plan so as to document how such proposed Co-Promotion for such Product is in the best interest of both Parties. Upon receipt of such written notice, MERCK shall enter into good faith negotiations with ARCHEMIX with the aim of determining whether or not to enter into a separate Co-Promotion agreement ("Co-Promotion Agreement") between the Parties. In the event MERCK, in its sole discretion, agrees to enter into such Co-Promotion Agreement with ARCHEMIX, then the terms applicable to such Co-Promotion of the Product identified therein (each, a "Co-Promoted Product") shall conform in all material respects with the terms, conditions and provisions set forth in Schedule 9 attached hereto and such additional provisions as are usual and customary for inclusion in a co-promotion agreement between companies in the pharmaceutical industry of comparable sizes to the respective Parties. For purposes of clarity, such additional terms shall supplement and shall not materially expand, limit or change the terms set forth on Schedule 9 . The Parties shall negotiate the Co-Promotion Agreement in good faith and with sufficient diligence as is required to execute and deliver the Co-Promotion Agreement within [***] days after ARCHEMIX provides its written indication of interest pursuant to the first sentence of this paragraph.                (b)  Failure to Agree . To the extent that MERCK enters into and conducts negotiations with respect to the Co-Promotion Agreement for a Product in good faith and the Parties fail to execute and deliver the Co-Promotion Agreement within [***] day period described in Section 4.9.2(a) above, then (i) MERCK shall continue to have the exclusive right and responsibility during the Term to Commercialize such Product in the Territory (including the United States of America and its territories and possessions) for use in the Field and (ii) the fact 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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that the Parties were unable to agree on a Co-Promotion Agreement shall not entitle ARCHEMIX to claim damages or any other sort of compensation whatsoever.      4.10 Product Recalls . In the event that any Regulatory Authority issues or requests a recall or takes similar action in connection with a Product, or in the event a Party reasonably believes that an event, incident or circumstance has occurred that may result in the need for a recall, market withdrawal or other corrective action regarding a Product, such Party shall promptly advise the other Party thereof by telephone or facsimile. Following such notification, MERCK shall decide and have control of whether to conduct a recall or market withdrawal (except in the event of a recall or market withdrawal mandated by a Regulatory Authority, in which case it shall be required) or to take other corrective action in any country and the manner in which any such recall, market withdrawal or corrective action shall be conducted; provided, that, MERCK shall keep ARCHEMIX regularly informed regarding any such recall, market withdrawal or corrective action. MERCK shall bear all expenses of any such recall, market withdrawal or corrective action (including, without limitation, expenses for notification, destruction and return of the affected Product and any refund to customers of amounts paid for such Product). 5. PAYMENTS      5.1 Technology Access and License Fee . MERCK shall pay ARCHEMIX a non-refundable technology access and license fee in the amount of Three Million Dollars (US $3,000,000) by wire transfer within thirty (30) days of the Effective Date, according to instructions that ARCHEMIX shall provide.      5.2 License Maintenance Fee . MERCK shall pay ARCHEMIX a non-refundable license maintenance fee in the amount of [***] Dollars (US $[***]) by wire transfer within [***] days of (i) the Effective Date and (ii) on each of the [***] of the Effective Date during the Research Program Term, according to instructions that ARCHEMIX shall provide.      5.3 R&D Funding .           5.3.1 Payment of R&D Funding . In consideration of the performance by ARCHEMIX of its activities under the Annual Research Plan(s) as described in Section 3.2, during the Research Program Term MERCK will pay ARCHEMIX the applicable Quarterly FTE Payment on or prior to the first day of each Calendar Quarter; provided, that, an invoice corresponding with such Calendar Quarter has been received by MERCK. Notwithstanding the above, in view of the activities to be performed by ARCHEMIX during the initial Calendar Quarter, MERCK will pay ARCHEMIX [***] Dollars (US $[***]) on the Effective Date; provided, that, an invoice corresponding with the initial Calendar Quarter has been received by MERCK. ARCHEMIX shall provide a report to the JPT within [***] days of the end of each Calendar Quarter during the Research Program Term that specifies the actual number of FTEs expended during the period covered therein. Within [***] days of the end of each Calendar Year during the Research Program Term, ARCHEMIX shall provide MERCK with an annual reconciliation statement ("Annual Reconciliation Statement") that specifies the actual number of FTEs expended during the previous [***] Calendar Quarters in the aggregate. MERCK shall 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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reimburse ARCHEMIX in full for any FTEs expended by ARCHEMIX in excess of the cumulative FTE Costs owed by MERCK for such Calendar Year (the "MERCK Contribution") as indicated by any Annual Reconciliation Statement if such excess was approved by the JSC. To the extent that any Annual Reconciliation Statement indicates that ARCHEMIX expended FTEs in excess of the MERCK Contribution and such excess was not approved by the JSC then, (a) MERCK shall reimburse ARCHEMIX for all amounts in excess of the MERCK Contribution, not to exceed [***] percent ([***]%) of the MERCK Contribution and (b) all FTE Costs in excess of [***] percent ([***]%) of the MERCK Contribution shall be borne by ARCHEMIX.           5.3.2 R&D Funding Audit Rights . ARCHEMIX shall keep complete and accurate books and financial records pertaining to the number of FTEs utilized in conducting the Research Program and the ARCHEMIX Development Activities, if any, which books and financial records shall be kept in accordance with GAAP and shall be retained by ARCHEMIX until [***] years after the end of the Contract Year to which they pertain. Upon [***] days written notice, MERCK shall have the right to appoint at its expense an independent certified public accountant reasonably acceptable to ARCHEMIX to audit the books and financial records of ARCHEMIX relating to the number of FTEs utilized in conducting the Research Program and the ARCHEMIX Development Activities during any Contract Year; provided, that, MERCK shall not have the right to audit any Contract Year more than once or more than [***] years after the end of such Contract Year or to conduct more than one such audit in any [***] period. All books and financial records made available for audit shall be deemed to