FEASIBILITY STUDY, LICENSE AND OPTION AGREEMENT

Exhibit 10.47 FEASIBILITY STUDY, LICENSE AND OPTION AGREEMENT      This Feasibility Study, License and Option Agreement (this " Agreement ") is made effective as of August 31, 2008 (the " Effective Date "), by and between Archemix Corp, a Delaware corporation with offices at 300 Third Street, Cambridge, Massachusetts 02142 (" Archemix "), and Eli Lilly and Company, an Indiana corporation with a business address at Lilly Corporate Center, Indianapolis, Indiana 46285 (" Lilly "). Archemix and Lilly are each sometimes hereinafter referred to individually as a "Party" and collectively as the "Parties."      WHEREAS, Archemix is the owner of or otherwise controls, certain patents related to (a) the identification and optimization of aptamers using its proprietary SELEX Process and SELEX Technology (each as defined herein) and (b) the use of such aptamers for controlling, curing, treating, preventing or delaying the onset or progression of human diseases and conditions;      WHEREAS, Lilly desires to obtain an option to have Archemix conduct a Feasibility Study (as defined herein) with the objective of demonstrating Archemix’s ability to generate high-affinity aptamer hits against targets of therapeutic interest to Lilly and, to the extent high-affinity aptamers are obtained, to obtain an additional option to enter into a collaboration and license agreement for a specified number of targets; and      WHEREAS, Archemix is willing to grant Lilly such options and to conduct such Feasibility Study on the terms and subject to the conditions of this Agreement.      NOW, THEREFORE, in consideration of the mutual covenants contained herein, and for other good and valuable consideration, the receipt and adequacy of which are hereby acknowledged, the Parties hereby agree as follows: 1. DEFINITIONS      Whenever used in the Agreement with an initial capital letter, the terms defined in this Article 1 shall have the meanings specified and may be used in singular or plural.      1.1 " Active Aptamer " means any Aptamer identified in the conduct of the Feasibility Study or otherwise under this Agreement during the Feasibility Study Term, in any case, that binds with high specificity and affinity to a Feasibility Study Target and any Aptamer(s) Derived therefrom that binds with high specificity and affinity to such Feasibility Study Target at a level to be discussed and agreed upon by the Parties, but typically having dissociation constants in the range of [***].      1.2 " Affiliate " means, with respect to any Person, any other Person that, directly or indirectly, controls or is controlled by or is under common control with, such Person. For purposes of this definition, "control" means (a) ownership of fifty percent (50%) or more of the shares of stock entitled to vote for the election of directors in the case of a corporation 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 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.

body of an entity other than a corporation.      1.3 " AME Patent Rights " means (a) the patents described in Schedule 1 attached hereto; (b) any patent application claiming priority to any such patent or to which any such patent claims priority; (c) any divisional, continuation, continuation-in-part (to the extent that the continuation-in-part is entitled to the priority date of an initial patent or patent application which is the subject of this Agreement), reissue, reexamination, confirmation, revalidation, registration, patent of addition, renewal, extension or substitute thereof, or any patent issuing therefrom or any supplementary protection certificates related thereto, as well as any certificate of invention or applications therefrom; and (d) all foreign equivalents of any of the foregoing.      1.4 " 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 may be in effect from time to time during the Term and are applicable to a particular activity hereunder.      1.5 " Aptamer " means any naturally or non-naturally occurring oligonucleotide identified through the SELEX Process but excluding Spiegelmers.      1.6 " Aptamer-Related Patent Rights "means any Patent Rights that contain one or more claims that cover Aptamer-Related Technology.      1.7 " Aptamer-Related Technology "means any Feasibility Study Technology that (a) relates, directly or indirectly, to Aptamers, including  the manufacture, formulation, delivery or use of Aptamers and (b) is conceived or first reduced to practice by employees of, or consultants to, Lilly or Archemix, alone or jointly with any Third Party. For purposes of clarity, Aptamer-Related Technology shall not include any Active Aptamers.      1.8 " Archemix Background Technology "means any Technology that is used by Archemix, or provided by Archemix for use, in the Feasibility Study 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 the Feasibility Study. For purposes of clarity, Archemix Background Technology shall include the SELEX Process and SELEX Technology.      1.9 " Archemix Collaboration Partner " means any Third Party with whom Archemix is engaged, from time to time, in an active bona fide collaborative effort to research, identify, characterize, optimize, develop and/or commercialize Archemix Products, which collaborative effort is evidenced by a written agreement. For purposes of clarity, as used in this definition, a "collaborative effort" includes, without limitation, out-licensing of products developed by Archemix or its Affiliates. Archemix acknowledges and agrees that Archemix is not authorized to sublicense the Lilly Patent Rights to any third party, except under such a collaboration agreement and that no Archemix Collaboration Partner may further sublicense, assign or otherwise transfer rights under the Lilly Patent Rights unless such further sublicense, assignment or other transfer is limited to the research, identification, characterization, optimization, development and/or commercialization of Archemix Products that originated from Portions of this Exhibit were omitted and have been filed separately with the Secretary of the Commission pursuant to the Company’s application requesting confidential treatment under Rule 406 of the Securities Act.

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Archemix or the specific collaborative effort between Archemix and such Third Party.      1.10 " Archemix Feasibility Study Activities "means all activities specified to be conducted by Archemix in any Feasibility Study Plan. Without limiting the foregoing, Archemix Feasibility Study Activities shall include the application of the SELEX Process and SELEX Technology to generate Active Aptamers against Feasibility Study Targets.      1.11 " Archemix Feasibility Study Technology "means any Feasibility Study Technology that is conceived or first reduced to practice by employees of, or consultants to, Archemix, alone or jointly with any Third Party. For purposes of clarity, Archemix Feasibility Study Technology shall include all Active Aptamers.      1.12 " Archemix Field "means any and all uses.      1.13 " Archemix-Gilead Collaboration Agreement " means the Collaboration Agreement between Gilead Sciences, Inc. and Archemix dated October 21, 2001, as amended.      1.14 " Archemix Materials "means any Proprietary Materials that are Controlled by Archemix and used by Archemix, or provided by Archemix for use, in the Feasibility Study. For purposes of clarity, Archemix Materials shall include all Aptamers.      1.15 " Archemix Patent Rights "means any Patent Rights Controlled by Archemix that contain one or more claims that cover Archemix Technology.      1.16 " Archemix Portfolio " means those Patent Rights covering the processes used for the identification or generation of a nucleic acid that binds to a Target by means other than Watson-Crick base-pairing as set forth in Schedule 3 .      1.17 " Archemix Product "means any product comprised of an Aptamer.      1.18 " Archemix Technology "means, collectively, Archemix Background Technology and Archemix Feasibility Study Technology.      1.19 " Calendar Year " means the period beginning on the Effective Date and ending on December 31 of the year in which the Effective Date falls and thereafter each successive period of twelve (12) months commencing on January 1 and ending on December 31.      1.20 " Challenge " means any challenge to the validity or enforceability of any Archemix Patent Right or Lilly Patent Right in the absence of a breach of this Agreement including, without limitation, by (a) filing a declaratory judgment action in which any Archemix Patent Right or Lilly Patent Right is alleged to be invalid or unenforceable; (b) citing prior art pursuant to [***], filing a request for re-examination of any Archemix Patent Right or Lilly Patent Rights pursuant to [***] or provoking or becoming party to an interference with an application for any Archemix Patent Right or Lilly Patent Right pursuant to [***]; or (c) filing or commencing any reexamination, opposition, cancellation, nullity or similar proceedings against any Archemix Patent Right or Lilly Patent Right in any country.      1.21 " Collaboration Agreement "means the collaboration and license agreement to 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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be executed by the Parties upon the exercise of any Collaboration/License Option pursuant to Section 2.5.      1.22 " Commercially Reasonable Efforts " means, with respect to the activities of Archemix in conducting the Feasibility Study under this Agreement, the efforts and resources customarily used by similarly sized biotechnology companies in the performance of such research activities for other products owned by such companies which are of similar market potential and at a similar stage of development, taking into account the competitiveness of the market place, the regulatory structure involved and other relevant and material factors.      1.23 " Confidential Information " means all information and Technology disclosed or provided by, or on behalf of a Party (the " Disclosing Party ") to the other Party (the " Receiving Party ") or to any of the Receiving Party’s employees, consultants, Affiliates or sublicensees (" Representatives ") pursuant to or in connection with this Agreement; 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 Representatives, as demonstrated by 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 other than through a breach by the Receiving Party or its Representatives of a contractual obligation; (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 its Representatives; or (d) it is independently developed by or for the Receiving Party or its Representatives without reference to or use of any Confidential Information of the Disclosing Party or its Representatives as demonstrated by credible written documentation. For purposes of clarity, unless excluded from Confidential Information pursuant to the provisos of the preceding sentence, any scientific, technical or financial information Controlled by a Disclosing Party and disclosed at any meeting of the Parties shall constitute Confidential Information of the Disclosing Party.      1.24 " Control " or " Controlled " means 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.      1.25 " Derived " means directly identified, developed, created, synthesized, designed, resulting or generated from, conjugated to or complexed with.      1.26 " 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.      1.27 " Diagnostic Product " means, collectively, In Vitro Diagnostic Agents, In Vivo Diagnostic Agents and any product used for Diagnosis.      1.28 " FDA " means the United States Food and Drug Administration and any 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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successor agency or authority thereto.      1.29 " Feasibility Study" means the activities carried out by Archemix and Lilly pursuant to the Feasibility Study Plan.      1.30 " Feasibility Study Plan "means the written plan describing the activities to be carried out by Archemix and Lilly in conducting the Feasibility Study pursuant to this Agreement as set forth in Exhibit A , as such written plan may be amended, modified or updated from time-to-time.      1.31 " Feasibility Study Targets " means the Targets listed on the Feasibility Study Target List.      1.32 " Feasibility Study Target List "means the list of up to five (5) Feasibility Study Targets to be identified by Lilly upon exercise of the Feasibility Study Option.      1.33 " Feasibility Study 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 Feasibility Study during the Feasibility Study Term.      1.34 " Feasibility Study Term "means, with respect to each Feasibility Study Target, the period beginning on the acceptance by Archemix of such Feasibility Study Target pursuant to Section 2.3.4 and ending (a) with respect to any such Feasibility Study Target with regard to which no Active Aptamer is identified, a period of [***] following the initiation of Archemix Feasibility Study Activities with respect to such Feasibility Study Target; and (b) with respect to any Feasibility Study Target with regard to which an Active Aptamer is identified, a period of [***] following the delivery by Archemix to Lilly of quantities of such Active Aptamer pursuant to Section 2.4.5; provided, that, if this Agreement is terminated prior to the end of the Feasibility Study Term, the effective date of such early termination shall become the last day of the Feasibility Study Term. 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 " Field " means the control, prevention, treatment, cure or delay of onset or progression of any Indication in animals and humans, but excluding, without limitation, Diagnostic Products, In Vivo Imaging Applications, Radio Therapeutics and all non-therapeutic uses.      1.36 " Indication " means any indication, disease, disorder or condition in the Field, which can be treated, controlled, prevented, cured or the onset or progression of which can be delayed.      1.37 " In Vitro Diagnostic Agent " means any product that uses the SELEX Process or one or more Aptamers in the assay, testing or determination, outside of a living organism, of a substance in a test material. In Vitro Diagnostics shall include, among other things, the use of the SELEX Process or Aptamers 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); (b) of a substance on a test material such as cells (as in FACS analysis or other measurements of pathogens within biological samples); and (c) any other in vitro diagnostic use of the SELEX Process or Aptamers in drug development processes, including target identification, pre-clinical and clinical testing, and the following more specific examples of uses of Aptamer technology: (i) to observe, through protein profiling, protein levels moving up or down in diseases or models of diseases, and to evaluate whether such proteins are sensible targets for the development of therapeutic agents; (ii) to observe coordinated expression of protein pathways in a variety of biological states in various systems; (iii) to study protein or metabolite levels during pre-clinical drug candidate evaluation in response to putative therapeutic agents during clinical trials ( e.g. , as markers of efficacy or response); and (iv) to study human protein or metabolite levels in response to putative therapeutic agents during clinical trials ( e.g. , as markers of efficacy or response). Notwithstanding the above, In Vitro Diagnostic Agents do not include any of the above-identified activities directed at the discovery or development of Aptamers by Lilly under and pursuant to the terms of this Agreement.      1.38 " 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.      1.39 " Joint Patent Rights "means (a) all Patent Rights that contain one or more claims that cover Joint Technology and (b) all Aptamer-Related Patent Rights.      1.40 " Joint Technology "means (a) any Feasibility Study Technology that is jointly conceived or first reduced to practice (actively or constructively) by employees of, or consultants to, Lilly and employees of, or consultants to, Archemix and (b) all Aptamer-Related Technology.      1.41 " Kauffman-Ixsys Agreement " means the License Agreement between Stuart A. Kauffman, M.D. and Ixsys, Inc. dated November 3, 1994, as amended. 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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     1.42 " Knowledge " means, with respect to Archemix, the actual knowledge of the chief executive officer, any vice president or the chief legal officer of Archemix.      1.43 " Lilly Feasibility Study Technology "means any Feasibility Study Technology that (a) is conceived or first reduced to practice by employees of, or consultants to, Lilly, alone or jointly with any Third Party and (b) is not Aptamer-Related Technology.      1.44 " Lilly Target Specific Patent Rights "means any Patent Rights Controlled by Lilly during the Feasibility Study Term that contain one or more claims that cover Lilly Target Specific Technology.      1.45 " Lilly Target Specific Technology "means any Technology that is Controlled by Lilly during the Feasibility Study Term that is necessary or useful for the conduct of the Feasibility Study involving any Feasibility Study Target.      1.46 " Lilly Materials "means any Proprietary Materials that are Controlled by Lilly and provided by Lilly for use in the Feasibility Study. For purposes of clarity, Lilly Materials shall include all Feasibility Study Targets provided to Archemix for use in the Feasibility Study.      1.47 " Lilly Patent Rights "means (a) any Patent Rights Controlled by Lilly that contain one or more claims that cover Lilly Technology and (b) AME Patent Rights.      1.48 " Lilly Technology "means, collectively, Lilly Feasibility Study Technology and Lilly Target-Specific Technology.      1.49 " Patent Rights " means all rights and interests in and to issued patents and pending patent applications including, without limitation, non-provisional patent applications, and all divisions, continuations and continuations-in-part thereof, patents issuing on any of the foregoing, all reissues, reexaminations, renewals and extensions thereof, and supplementary protection certificates therefor, as well as any certificates of invention or applications therefor, and all foreign equivalents of any of the foregoing.      1.50 " 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.      1.51 " Radio Therapeutics " 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.      1.52 " SELEX Process " means the processes used for the identification or generation of a nucleic acid that binds to a Target by means other than Watson-Crick base-pairing covered by the claims in (a) the SELEX Portfolio, (b) the Archemix Portfolio or (c) any continuation, 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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divisional, continuation-in-part, substitution, renewal, reissue, re-examination or extension, or any foreign equivalent, of any such claims.      1.53 " SELEX Portfolio " means those Patent Rights licensed by Gilead to Archemix pursuant to the Archemix-Gilead Collaboration Agreement set forth in Schedule 4 .      1.54 " SELEX Technology " means (a) oligonucleotides that bind to a Feasibility Study Target by means other than Watson-Crick base-pairing that consist of or incorporate structural elements that are generally applicable to such oligonucleotides independent of Feasibility Study Targets (e.g., a novel nucleoside, bond or linkage or combination(s) thereof, for example, deoxypurine and 2’O-methyl substituted prymidine compositions) as used in such oligonucleotides, and (b) any process for modifying, optimizing and/or stabilizing oligonucleotides that bind to a Feasibility Study Target by means other than Watson-Crick base-pairing that is generally applicable to such oligonucleotides independent of Feasibility Study Targets wherein such modification, optimization or stabilization includes, without limitation, minimization, truncation, conjugation, pegylation, complexation, substitution, deletion and/or incorporation of modified nucleotides; provided, however, that SELEX Technology does not include Active Aptamers and that the SELEX Technology is covered by the claims in (a) the SELEX Portfolio, (b) the Archemix Portfolio, or both or (c) any continuation, divisional, continuation-in-part, substitution, renewal, reissue, re-examination or extension, or any foreign equivalent, of any such claims.      1.55 " Spiegelmer "means an oligonucleotide consisting of at least [***] percent ([***]%) [***], including any structural variations and modifications, derivatives, homologs, analogs and/or mimetics to the [***] components (other than [***]), identified through the use of the SELEX Process.      1.56 " Target " means a protein, cytokine, enzyme, receptor, transducer, transcription factor, antigen or any other non-nucleic acid molecule.      1.57 " 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 any negative results).      1.58 " Territory " means all countries and jurisdictions of the world.      1.59 " Third Party " means any person or entity other than Lilly, Archemix and their respective Affiliates.      1.60 " ULEHI " means University License Equity Holdings, Inc., formerly known as UTC.      1.61 " URC Collaboration Agreement " means the Restated Assignment and Collaboration Agreement, dated July 17, 1991, by and between University Research Corporation and Gilead Sciences, Inc. as successor in interest to NeXstar Pharmaceuticals, Inc. 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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     1.62 " UTC " means University Technology Corporation, the successor in interest to the University Research Corporation.       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. GRANT OF RIGHTS      2.1 Grant of Licenses to Archemix .           2.1.1 Grant of Licenses . Subject to the other terms and conditions of this Agreement and in consideration of the grant by Archemix to Lilly of the rights set forth in Sections 2.2 and 2.5, Lilly hereby grants to Archemix (a) a non-exclusive, royalty-free, fully paid-up license during the Feasibility Study Term, without the right to grant sublicenses, under all Lilly Target Specific Technology and Lilly Target Specific Patent Rights to conduct the Feasibility Study with the Feasibility Study Targets that are identified in a Feasibility Study Option Exercise Notice (the " Feasibility Study License ") and (b) a non-exclusive, royalty-free, fully paid-up, perpetual, irrevocable (except in the event of termination by Lilly under Section 7.2.3 during the Feasibility Study Term when such license shall be revocable for material breach or as extended during the Collaboration/License Negotiation Period under Section 2.5.2(a), if applicable), worldwide license, with the right to grant sublicenses to Archemix Collaboration Partners, under AME Patent Rights, to research, develop, make, have made, use, have used, sell, offer for sale, have sold, import, have imported, export, have exported, and commercialize Archemix Products within the Archemix Field (the " Archemix AME License ").      2.2 Grant of Feasibility Study Option to Lilly .           2.2.1 Feasibility Study Option Grant . Archemix hereby grants Lilly an option (the " Feasibility Study Option ") to have Archemix conduct the Feasibility Study for the purpose of having Archemix demonstrate its ability to generate Active Aptamers against Feasibility Study Targets.           2.2.2 Feasibility Study Option Exercise . Subject to Section 2.2.3, Lilly shall have the right to exercise the Feasibility Study Option at any time during the period commencing on the Effective Date and continuing until [***] (the " Feasibility Study Option Period "), by delivering written notice of exercise thereof (the " Feasibility Study Option Exercise Notice ") on or before the expiration of the Feasibility Study Option Period, which Feasibility Study Option Exercise Notice shall include the Feasibility Study Target Notice. Upon the exercise by Lilly of the Feasibility Study Option, (a) Lilly shall be deemed to have granted Archemix the Feasibility Study License set forth in Section 2.1.1(a) and (b) Archemix shall commence the Feasibility Study with respect to the Feasibility Study Targets identified in the Feasibility Study Option Exercise Notice within [***] of the date of such exercise; provided, that, (i) Lilly has provided Archemix with the materials and resources as set forth in Section 2.4.2 and (ii) notwithstanding the foregoing, Archemix shall not be required to initiate the Feasibility Study prior to [***].           2.2.3 Feasibility Study Option Expiration . In the event that Lilly fails to (a) exercise the Feasibility Study Option on or before the expiration of the Feasibility Study Option Period, or (b) provide the materials and resources required by Section 2.4.2 on a timely basis following the exercise by Lilly of the Feasibility Study Option, all rights granted by Archemix to Lilly pursuant to this Agreement with respect to the Feasibility Study Option shall terminate at Archemix’s sole discretion and upon notice to Lilly. 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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     2.3 Designation of Feasibility Study Targets .           2.3.1 Designation of Feasibility Study Targets . Subject to Sections 2.3.3, 2.3.4 and 2.3.5, during the period commencing on the Effective Date and continuing until the expiration of the Feasibility Study Option Period, Lilly shall have the one-time right to request that up to [***] Targets be accepted by Archemix as Feasibility Study Targets and included on the Feasibility Study Target List by providing written notice to Archemix, which notice shall identify each such proposed Feasibility Study Target (each, a " Feasibility Study Target Notice "). Archemix shall determine whether to accept or reject any such proposed Feasibility Study Target pursuant to Section 2.3.4. To the extent Archemix accepts any Target for inclusion as a Feasibility Study Target on the Feasibility Study Target List in accordance with Section 2.3.4 such Target shall be included as a Feasibility Study Target. To the extent that Archemix rejects any Target for inclusion as a Feasibility Study Target on the Feasibility Study Target List in accordance with Section 2.3.4 Lilly shall have no rights under this Agreement with respect to such Target.           2.3.2 Designation of Exclusive Feasibility Study Targets . Subject to Sections 2.3.3, 2.3.4 and 2.3.5, during the period commencing on Archemix’s receipt of the Feasibility Study Option Exercise Notice and Feasibility Study Target Notice and continuing until the expiration of the Feasibility Study Term, Lilly shall have the right to request that up to two (2) Feasibility Study Targets be accepted by Archemix as exclusive Feasibility Study Targets (each, an " Exclusive Feasibility Study Target ") and designated on the Feasibility Study Target List as Exclusive Feasibility Study Targets by providing written notice to Archemix, which notice shall identify each such proposed Exclusive Feasibility Study Target (each, an " Exclusive Feasibility Study Target Notice "). To the extent Archemix accepts any Feasibility Study Target for designation as an Exclusive Feasibility Study Target on the Feasibility Study Target List in accordance with Section 2.3.4 during the Feasibility Study Term, Archemix shall not, and shall cause each of its Affiliates to not, conduct any activity, that involves the research, development or commercialization of, or grant any license or other rights to any Archemix Collaboration Partner under any Proprietary Materials, Technology or Patent Rights Controlled by Archemix or any of its Affiliates to research, develop or commercialize, any Aptamer binding to such Exclusive Feasibility Study Target in the Field. To the extent that Archemix rejects any Target for designation as an Exclusive Feasibility Study Target on the Feasibility Study Target List in accordance with Section 2.3.4, such Feasibility Study Target will remain a Feasibility Study Target and Lilly shall have no exclusive rights under this Agreement with respect to such Feasibility Study Target. For purposes of clarity, Lilly shall have no rights under this Agreement with respect to any Target unless and until such Target is proposed by Lilly pursuant to Section 2.3.1 and accepted by Archemix as a Feasibility Study Target pursuant to Section 2.3.4.           2.3.3 Selection of Proposed Targets . Lilly hereby agrees that it shall propose Targets for inclusion as Feasibility Study Targets only after reasonable consultation and discussion with Archemix and only after consideration by Lilly of the technical feasibility and availability of such Targets.           2.3.4 Acceptance/Rejection of Feasibility Study Targets by Archemix . To the extent Lilly requests the inclusion of a Target as a Feasibility Study Target pursuant to Sections 2.3.1 or the designation of a Feasibility Study Target as an Exclusive Feasibility Study 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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pursuant to Section 2.3.2, Archemix shall accept or reject the proposed Target within [***] days after receipt of such notice from Lilly. A Target proposed by Lilly for inclusion on the Feasibility Study Target List or for designation as an Exclusive Feasibility Study Target on the Feasibility Study Target List may only be rejected by Archemix if prior to Lilly’s notice (a) Archemix is prohibited by an executed contract from licensing Aptamers against such proposed Target or its natural ligand(s), to Lilly, (b) Archemix is in active negotiations, as demonstrated by written term sheets with a Third Party with respect to a license, collaboration or similar agreement relating to Aptamers against such Target or its natural ligand(s), (c) 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 or (d) Archemix has identified such Target as a cardiovascular or hematologic Target of strategic interest to Archemix, in each of (c) and (d) as demonstrated by credible written evidence. If Lilly requests the inclusion of [***] or more Targets as Feasibility Study Targets pursuant to Section 2.3.1 or the designation of two (2) or more Feasibility Study Targets as Exclusive Feasibility Study Targets pursuant to Section 2.3.2 and Archemix accepts less than [***] such Feasibility Study Targets and/or less than two (2) Exclusive Feasibility Study Targets pursuant to this Section 2.3.4, Lilly shall have up to [***] additional periods of [***] days each, each such period to begin upon receipt of the applicable notice from Archemix rejecting or accepting proposed Targets, to request that additional Targets be included as Feasibility Study Targets pursuant to Section 2.3.1 or additional Feasibility Study Targets be designated as Exclusive Feasibility Study Targets pursuant to Section 2.3.2, subject in either case to Section 2.3.5, until such time as [***] Feasibility Study Targets and two (2) Exclusive Feasibility Study Targets have been accepted by Archemix pursuant to this Section 2.3.4.           2.3.5 Limitation on Number of Feasibility Study Targets and Exclusive Feasibility Study Targets . Notwithstanding anything to the contrary in this Agreement, under no circumstances shall Lilly have, at any one time, (a) more than [***] Feasibility Study Targets on the Feasibility Study Target List nor (b) more than two (2) Exclusive Feasibility Study Targets on the Feasibility Study Target List.      2.4 Conduct of Feasibility Study .           2.4.1 Archemix Responsibilities . Commencing as of the date of exercise of the Feasibility Study Option, Archemix shall use Commercially Reasonable Efforts, including committing such resources as are reasonably necessary for Archemix to conduct the Feasibility Study described in the Feasibility Study Plan, to conduct the Archemix Feasibility Study Activities and complete its obligations set forth in the Feasibility Study Plan on or before [***] months from the initiation of such Feasibility Study; provided, that, notwithstanding the foregoing, (a) all Archemix Feasibility Study Activities with respect to Feasibility Study Targets shall be initiated by Archemix on the same date and (b) no Feasibility Study Targets may be proposed by Lilly after the initiation by Archemix of such Archemix Feasibility Study Activities           2.4.2 Lilly Rights and Responsibilities . Upon exercise of the Feasibility Study Option, Lilly shall: (a) provide Archemix with the sufficient quantities of each Feasibility Study Target set forth in the applicable Feasibility Study Option Exercise Notice within [***] months of the delivery by Lilly of such Feasibility Study Option Exercise Notice and acceptance by Archemix of the Feasibility Study Targets and in sufficient form for the conduct of 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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Feasibility Study; (b) commit such resources as are reasonably necessary for Archemix to conduct the Feasibility Study described in the Feasibility Study Plan; and (c) as soon as practicable conduct in vitro functional assays with respect to all Active Aptamers supplied by Archemix pursuant to Section 2.4.5 until expiration of the Feasibility Study Term. In connection therewith, Lilly hereby agrees to use such Active Aptamers solely to conduct in vitro functional assays covering such Active Aptamers and for no other use or purpose and hereby acknowledges that all such Active Aptamers shall be Proprietary Materials of Archemix and subject to Section 2.4.6.           2.4.3 Compliance . Archemix shall perform its obligations under the Feasibility Study Plan in compliance in all material respects with all Applicable Laws.           2.4.4 Reports . Archemix shall at least [***] each Calendar Quarter during the Feasibility Study Term, provide reports to Lilly in reasonable detail regarding the status of its activities under the Feasibility Study. Archemix shall make itself available at reasonable times to provide Lilly with telephonic, email and other updates as Lilly reasonably requests.           2.4.5 Supply of Active Aptamers by Archemix . To the extent that Archemix identifies Active Aptamers in the conduct of the Feasibility Study, Archemix shall, as soon as practicable following the issuance of the report identifying such Active Aptamers, supply Lilly with a quantity of such Active Aptamer sufficient for Lilly to conduct in vitro functional assays covering such Active Aptamer.           2.4.6 Supply of Proprietary Materials . To the extent that either Party (the " Transferring Party ") supplies the other Party (the " Recipient Party ") with Proprietary Materials of the Transferring Party for use in the Feasibility Study, 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; provided, however, that Lilly may transfer such Proprietary Materials under a material transfer agreement or equivalent agreement to (x) bona fide collaborators as part of a research collaboration where work is being done primarily for Lilly’s benefit and (y) contractors for services related to the Proprietary Materials; provided further, however, that each such agreement under (x) and (y) states that the Proprietary Materials may not be transferred to another Third Party and are otherwise subject to the other terms and conditions of this Agreement to the benefit of Archemix; (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 Feasibility Study 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.           2.4.7 Feasibility Study Term . The Feasibility Study shall commence on the first day of the Feasibility Study Term and shall continue until the last to expire Feasibility Study Term.      2.5 Grant of Collaboration/License Option to Lilly . 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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          2.5.1 Grant of Collaboration/License Option . Archemix hereby grants Lilly, with respect to each Feasibility Study Target, an option (each a " Collaboration/License Option ") to enter into a collaboration and exclusive license agreement in the Territory under Archemix Patent Rights and Archemix Technology with respect to up to [***] Feasibility Study Targets for the purpose of researching, developing, making, having made, using, having used, selling, having sold, offering for sale, importing, having imported, exporting and having exported Active Aptamers directed to such Feasibility Study Targets for any and all uses within the Field. For purposes of clarity, Collaboration/License Options shall only be available with respect to Feasibility Study Targets that are listed on the Feasibility Study Target List.           2.5.2 Collaboration/License Option Exercise; Negative Covenants .                (a)  Collaboration/License Option . Subject to Section 2.5.3, Lilly shall have the right to exercise each Collaboration/License Option at any time during the Feasibility Study Term (the " Collaboration/License Option Period ") by delivering written notice of exercise thereof (the " Collaboration/License Option Exercise Notice ") on or before the expiration of the Collaboration/License Option Period, which Collaboration/License Option Exercise Notice shall specify the Feasibility Study Target that is the subject of the Collaboration/License Option. Upon the exercise of a Collaboration/License Option with respect to a Feasibility Study Target as provided in this Section 2.5.2, the Parties shall negotiate in good faith a separate Collaboration and License Agreement (each, a " Collaboration Agreement ") covering such Feasibility Study Target for a period of up to [***] months (the " Collaboration/License Negotiation Period "), which Collaboration Agreement shall include the terms, conditions and provisions set forth in Schedule 2 attached hereto and such additional provisions as are usual and customary for inclusion in a collaboration and license 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 2 . In the event that, notwithstanding such good faith efforts, the Parties fail to execute and deliver the Collaboration Agreement within the Collaboration/License Negotiation Period, the Parties shall (a) use reasonable efforts to complete such negotiations and to execute and deliver the Collaboration Agreement as soon as possible after such Collaboration/License Negotiation Period, and (b) without limiting the generality of the foregoing, after the expiration of such additional period, each produce a list of issues not otherwise set forth on Schedule 2 on which they have failed to reach agreement and submit its list to the Third Party Expert to be resolved in accordance with Section 8.2.2 (a " Negotiation Dispute" ).                (b)  Negative Covenants . Notwithstanding anything to the contrary in this Agreement, Lilly shall not be granted the right in any Collaboration Agreement to, and hereby covenants and agrees that neither it nor its Affiliates will under any such Collaboration Agreement (i) use the SELEX Process or SELEX Technology (A) on any Target that is not the Feasibility Study Target that is the subject of the Collaboration Agreement and (B) except for the purpose of identifying or modifying Active Aptamers against the Feasibility Study Target that is the subject of the Collaboration Agreement as expressly permitted under the Collaboration Agreement, (ii) research, develop, make, have made, use, have used, sell, offer for sale, have sold, distribute for sale, import, have imported, export or have exported Diagnostic Product or (iii) perform any research or development on Active Aptamers for any use outside of the Field. Notwithstanding the foregoing, Lilly shall not be restricted by this Section 2.5.2(b) from engaging 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 any activity in which Lilly is permitted to engage pursuant to a license, sublicense or other right granted to Lilly in any agreement other than the Collaboration Agreement with respect to the SELEX Portfolio, the SELEX Process, SELEX Technology or Aptamers, whether granted by Archemix, or any Third Party having the right to grant such license, sublicense or other right. To the extent Lilly or its Affiliates engages in any activities in violation of the negative covenants set forth in this Section 2.5.2(b) during the term of the Collaboration Agreement and files any patent applications or obtains any Patent Rights related to or arising out of such activities then, without limiting any other remedy Archemix may have under this Agreement and without any further action of either Party, if Lilly has willfully undertaken such activities, then Lilly shall be deemed to have granted to Archemix, effective as of the date of any such filing, or the date on which such Patent Rights are obtained, an exclusive, fully-paid, perpetual, irrevocable, royalty-free license under all such patent applications and Patent Rights for any and all uses; if Lilly has not willfully undertaken such activities (i.e., it is not culpable), then Lilly shall be deemed to have granted to Archemix, effective as of the date of any such filing, or the date on which such Patent Rights are obtained, a non-exclusive, fully-paid, perpetual, irrevocable, royalty-free license under all such patent applications and Patent Rights for any and all uses.           2.5.3 Option Expiration . In the event that Lilly fails to exercise any Collaboration/License Option on or before the expiration of the Collaboration/License Option Period (each, an " Expired Collaboration/License Option "), (a) all rights granted by Archemix to Lilly pursuant to this Agreement with respect to each such Expired Collaboration/License Option shall terminate and (b) Archemix shall promptly return to Lilly all Lilly Materials provided to Archemix and not otherwise the subject of a Collaboration Agreement. 3. TREATMENT OF CONFIDENTIAL INFORMATION      3.1 Confidentiality Obligations . Archemix and Lilly each recognizes that the other Party’s Confidential Information constitutes highly valuable assets of such other Party. Archemix and Lilly each agrees that, subject to the remainder of this Article 3, it will hold in confidence and will not disclose, and will cause its Affiliates and sublicensees not to disclose, any Confidential Information of the other Party and it will not use, and will cause its Affiliates and sublicensees not to use, any Confidential Info