COLLABORATION AND LICENSE AGREEMENT BY AND BETWEEN ALNYLAM PHARMACEUTICALS, INC. AND BIOGEN IDEC MA INC

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Exhibit 10.1

Confidential Materials omitted and filed separately with the

Securities and Exchange Commission. Asterisks denote omissions.

COLLABORATION AND LICENSE AGREEMENT

BY AND BETWEEN

ALNYLAM PHARMACEUTICALS, INC.

AND

BIOGEN IDEC MA INC.

Confidential

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COLLABORATION AND LICENSE AGREEMENT

This Collaboration and License Agreement dated the 20th day of September, 2006

(the "Execution Date") is by and between Alnylam Pharmaceuticals, Inc., a

corporation organized and existing under the laws of the State of Delaware and

having its principal office at 300 Third Street, Third Floor, Cambridge,

Massachusetts 02142 ("Alnylam"), and Biogen Idec MA Inc., a corporation

organized and existing under the laws of the Commonwealth of Massachusetts and

having its principal office at 14 Cambridge Center, Cambridge, MA 02142 ("Biogen

Idec").

INTRODUCTION

WHEREAS, Alnylam has developed technology useful for the discovery, development,

manufacture, characterization or use of therapeutic products that function

through RNA interference;

WHEREAS, Biogen Idec is in the business of discovering, developing,

manufacturing and commercializing human therapeutic products;

WHEREAS, Alnylam and Biogen Idec are interested in collaborating, on the terms

and conditions set forth herein, in the discovery and development of RNAi

Therapeutics (as defined below) directed to the JC virus for use in the Field

(as defined below).

NOW, THEREFORE, Alnylam and Biogen Idec agree as follows:

ARTICLE 1

DEFINITIONS

When used in this Agreement, each of the following terms shall have the meanings

set forth in this Article 1:

1.1 "ACTIVE IND" means an IND submitted to a Regulatory Authority by

Biogen Idec or an Affiliate where such Regulatory Authority did not

notify Biogen Idec or such Affiliate within thirty (30) days of such

submission that it may not proceed under such IND.

1.2 "AFFILIATE" means any corporation, company, partnership, joint venture

and/or firm which controls, is controlled by, or is under common

control with a specified person or entity. For purposes of this

Section 1.2, "control" shall be presumed to exist if one of the

following conditions is met: (a) in the case of corporate entities,

direct or indirect ownership of at least fifty percent (50%) of the

stock or shares having the right to vote for the election of

directors, and (b) in the case of non-corporate entities, direct or

indirect ownership of at least fifty percent (50%) of the equity

interest with the power to direct the management and policies of such

non-corporate entities. The Parties acknowledge that in the case of

certain entities organized under the laws of certain countries outside

of the United States, the maximum percentage ownership permitted by

law for a foreign investor may

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be less than fifty percent (50%), and that in such case such lower

percentage shall be substituted in the preceding sentence, provided

that such foreign investor has the power to direct the management and

policies of such entity.

1.3 "ALNYLAM COLLABORATION IP" means (a) any improvement, discovery or

Know-How, patentable or otherwise, first identified, discovered or

developed solely by employees of Alnylam or its Affiliates, or other

persons not employed by Biogen Idec acting on behalf of Alnylam, under

the Collaboration, and (b) any Patent Rights in the Territory which

claim, cover or relate to such improvements, discoveries or Know-How

and are Controlled by Alnylam at any time during the Collaboration

Term. Alnylam Collaboration IP excludes Alnylam's interest in Joint

Collaboration IP.

1.4 "ALNYLAM IN-LICENSE" means an agreement between Alnylam and a Third

Party pursuant to which Alnylam has rights and obligations with

respect to, or which otherwise Cover, an RNAi Therapeutic and which is

necessary to Discover, Develop, Commercialize and/or Manufacture an

RNAi Therapeutic directed to JCV in the Field in the Territory,

including without limitation the Existing Alnylam In-Licenses.

1.5 "ALNYLAM KNOW-HOW" means Know-How that is either (a) Controlled by

Alnylam on the Effective Date, or (b) comes within Alnylam's Control

during the Term (other than Alnylam's rights in Joint Collaboration IP

and Alnylam Collaboration IP).

1.6 "ALNYLAM PATENT RIGHTS" means Patent Rights that (a) claim (i) Alnylam

Know-How, or (ii) the identification, characterization, optimization,

construction, expression, use or production of an RNAi Therapeutic,

and which are useful or necessary to Discover, Develop, Commercialize

and/or Manufacture a Selected RNAi Therapeutic in the Field in the

Territory, and (b) are Controlled by Alnylam at any time during the

Collaboration Term. As of the Execution Date, Alnylam Patent Rights

include, without limitation, those listed on Schedule 1.6. Alnylam

Patent Rights shall not include Patent Rights included in Alnylam

Collaboration IP.

1.7 "ALNYLAM TECHNOLOGY" means, collectively, Alnylam Know-How, Alnylam

Patent Rights, Alnylam Collaboration IP and Alnylam's interest in

Joint Collaboration IP.

1.8 "ANNUAL WORK PLAN" means the master plan for a given Contract Year for

the Discovery Program and the Development Program, an initial draft of

which is set forth in Schedule 1.8 for the first Contract Year, as

updated and approved by the Joint Steering Committee as necessary

during each subsequent Contract Year.

1.9 "BACK-UP CANDIDATE" means the RNAi Therapeutic directed to JCV that

[**] and has been [**] as a back-up [**].

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1.10 "BIOGEN IDEC COLLABORATION IP" means (a) any improvement, discovery or

Know-How, patentable or otherwise, first identified, discovered or

developed solely by employees of Biogen Idec or its Affiliates or

other persons not employed by Alnylam acting on behalf of Biogen Idec,

under the Collaboration, and (b) any Patent Rights in the Territory

which claim, cover or relate to such improvements, discoveries or

Know-How and are Controlled by Biogen Idec at any time during the

Collaboration Term. Biogen Idec Collaboration IP excludes Biogen

Idec's interest in Joint Collaboration IP.

1.11 "BIOGEN IDEC IN-LICENSE" means an agreement between Biogen Idec and a

Third Party pursuant to which Biogen Idec has rights and obligations

with respect to, or which otherwise Cover, an RNAi Therapeutic and is

necessary to Discover, Develop, Commercialize and/or Manufacture a

Selected RNAi Therapeutic in the Field in the Territory. Biogen Idec

In-Licenses as of the Execution Date are listed on Schedule 1.11.

1.12 "BIOGEN IDEC KNOW-HOW" means Know-How that is either (a) Controlled by

Biogen Idec on the Effective Date, or (b) comes within Biogen Idec's

Control during the Collaboration Term (other than Biogen Idec's rights

in Joint Collaboration IP and Biogen Idec Collaboration IP).

1.13 "BIOGEN IDEC PATENT RIGHTS" means Patent Rights that (a) claim (i)

Biogen Idec Know-How, or (ii) the identification, characterization,

optimization, construction, expression, use or production of an RNAi

Therapeutic, and which is useful or necessary to Discover, Develop,

Commercialize and/or Manufacture RNAi Therapeutics in the Field in the

Territory, and (b) are Controlled by Biogen Idec at any time during

the Collaboration Term. Biogen Idec Patent Rights shall not include

Patent Rights included in Biogen Idec Collaboration IP.

1.14 "BIOGEN IDEC TECHNOLOGY" means, collectively, Biogen Idec Know-How,

Biogen Idec Patent Rights, Biogen Idec Collaboration IP and Biogen

Idec's interest in Joint Collaboration IP.

1.15 "BLOCKING RNAi TECHNOLOGY" means Biogen Idec Collaboration IP

comprising Broad RNAi Technology which would, in the absence of a

license from Biogen Idec, be infringed by the practice of any

invention claimed in a Valid Claim of the Alnylam Patent Rights

existing at the end of the Discovery Term.

1.16 "BROAD RNAi TECHNOLOGY" means any and all Know-How, whether or not

patentable, that (a) is useful for the identification,

characterization, optimization, construction, expression, use or

production of an RNAi Therapeutic, (b) arises from or is necessary for

the performance of the Collaboration and (c) which relates to

structural features, properties, motifs, synthesis, analysis,

modifications, delivery and/or uses of siRNAs that has broader utility

beyond the specific embodiments represented by an RNAi Therapeutic

directed to JCV and/or particular uses of such RNAi Therapeutic.

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1.17 "BROAD RNAi TECHNOLOGY COLLABORATION IP" means Joint Collaboration IP

that constitutes Broad RNAi Technology.

1.18 "BUSINESS DAY" means a day on which banking institutions in Boston,

Massachusetts are open for business.

1.19 "CLINICAL PROOF OF CONCEPT" means, with respect to a Selected RNAi

Therapeutic, either (a) [**] data from a clinical trial of such

Selected RNAi Therapeutic [**]:

(i) [**]; or

(ii) [**].

1.20 "COLLABORATION" means the activities contemplated under this Agreement

aimed at the Discovery of RNAi Therapeutics directed to JCV, and the

Development and Manufacture of the Selected RNAi Therapeutics.

1.21 "COLLABORATION TERM" means the period commencing on the Effective Date

and ending on the earlier of (a) Regulatory Approval of a Selected

RNAi Therapeutic anywhere in the Territory, and (b) the Established

Utilization Date.

1.22 "COMMERCIALIZATION" or "COMMERCIALIZE" means any activity to

distribute, market, sell and/or have sold an approved Selected RNAi

Therapeutic.

1.23 "COMMERCIALLY REASONABLE EFFORTS" means the carrying out of

obligations in a diligent and sustained manner using such effort and

employing such resources (a) in Alnylam's case, as would normally be

exerted or employed by a similarly situated biopharmaceutical company

for a product of similar strategic importance, and at a similar stage

of its product life, based on conditions then prevailing; and (b) in

Biogen Idec's case, that are substantially similar to the effort and

resources Biogen Idec would devote to a product of similar commercial

or strategic importance, and at a similar stage of its product life,

taking into consideration safety and efficacy, development costs, the

anticipated prescription label, all payments due to Alnylam under this

Agreement and all other relevant factors, taking into account the

nature of the JCV RNAi Therapeutic and the clinical setting in which

it is expected to be used. Commercially Reasonable Efforts shall be

determined on a country-by-country basis.

1.24 "CONFIDENTIAL INFORMATION" means any and all information and data,

including without limitation all Alnylam Technology and Biogen Idec

Technology, and all other scientific, pre-clinical, clinical,

regulatory, manufacturing, marketing, financial and commercial

information or data, whether communicated in writing or orally or by

any other method, which is provided by one Party to the other Party in

connection with this Agreement.

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1.25 "CONTRACT YEAR" means the twelve (12) month period beginning on the

Effective Date and each succeeding twelve (12) month period thereafter

during the Term. Each Contract Year shall be divided into four (4)

"Contract Quarters" comprised of successive three (3) month periods.

1.26 "CONTROL" or "CONTROLLED" means with respect to any (a) material, item

of information, method, data or other know-how, or (b) intellectual

property right, the possession (whether by ownership or license, other

than pursuant to this Agreement) by a Party or its Affiliates of the

ability to grant to the other Party access and/or a license as

provided herein under such item or right without violating the terms

of any agreement or other arrangement with any Third Party existing

before or after the Effective Date.

1.27 "CORE JCV PATENTS" means Patent Rights Controlled by Alnylam, the

claims of which are specifically directed to (a) RNAi Therapeutics in

the Field, or (b) the manufacture or use of RNAi Therapeutics in the

Field. As of the Effective Date, Core JCV Patents include those

patents and applications set forth on Schedule 1.27.

1.28 "COST OF GOODS" means, with respect to a Selected RNAi Therapeutic,

the reasonable internal and external costs of Alnylam incurred in

Manufacturing such Selected RNAi Therapeutic (including [**]),

including: (a) to the extent that such Selected RNAi Therapeutic is

sourced from Alnylam, the [**] cost of Manufacture of such Selected

RNAi Therapeutic, consisting of [**], all calculated in accordance

with generally accepted accounting principles in the United States

consistently applied by Alnylam, and (b) to the extent that such

Selected RNAi Therapeutic is sourced from a Third Party manufacturer,

the actual price paid by Alnylam to the Third Party [**]. Cost of

Goods shall not include [**].

1.29 "COVERING", "COVER", or "COVERED" means, with respect to an RNAi

Therapeutic, that in the absence of a license granted under a Valid

Claim, the Discovery, Development, Manufacture or Commercialization of

the RNAi Therapeutic would infringe such Valid Claim.

1.30 "DEVELOPMENT" or "DEVELOP" means any preclinical and clinical activity

to develop a Selected RNAi Therapeutic, beginning with IND-Enabling

GLP Toxicology Studies and ending upon Regulatory Approval and

completion of any post-approval regulatory commitments.

1.31 "DEVELOPMENT CANDIDATE" means the RNAi Therapeutic directed to JCV

that meets the Development Criteria and has been selected by Biogen

Idec pursuant to Section 2.2 for further Development and

Commercialization.

1.32 "DEVELOPMENT CRITERIA" means the written criteria developed by the

Parties and approved by the Joint Steering Committee, and included in

the Annual Work Plan, for an RNAi Therapeutic directed to JCV to

qualify as a Selected RNAi Therapeutic.

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1.33 "DEVELOPMENT MATERIALS" means animal models, cell lines, tissue

samples, genes, plasmids, siRNAs, constructs, vectors, receptors and

other proteins, peptides, and other biological materials related to

RNAi Therapeutics that in each case are used in or that may be

necessary or useful to conduct the Collaboration.

1.34 "DISCOVERY" or "DISCOVER" means any and all activities to discover and

characterize potential Development Candidates during the Discovery

Term prior to the initiation of IND-Enabling Toxicology Studies,

including without limitation, the research and development activities

related to the generation, characterization, optimization,

construction, synthesis, use and production of potential Development

Candidates.

1.35 "DISCOVERY TERM" means the period commencing on the Effective Date and

continuing until the earlier to occur of (a) Alnylam having notified

Biogen Idec of the Discovery of [**], or (b) the last date of the

third Contract Year of the Term.

1.36 "EFFECTIVE DATE" means September 20, 2006.

1.37 "EMEA" means the European Medicines Agency and any successor agency

having substantially the same functions.

1.38 "ESTABLISHED UTILIZATION" means the [**].

1.39 "ESTABLISHED UTILIZATION YEAR" means the twelve (12) month period

beginning on the Established Utilization Date and each succeeding

twelve (12) month period thereafter. Each Established Utilization Year

shall be divided into four (4) "Established Utilization Quarters"

comprised of successive three (3) month periods.

1.40 "EXECUTIVE OFFICERS" means the Chief Executive Officer of Biogen Idec

(or an executive of Biogen Idec designated by such Chief Executive

Officer) and the Chief Executive Officer of Alnylam (or an executive

of Alnylam designated by such Chief Executive Officer).

1.41 "EXISTING ALNYLAM IN-LICENSES" means the Third Party agreements listed

on Schedule 1.41, redacted copies of which have been provided to

Biogen Idec prior to the Execution Date, as such schedule may be

amended pursuant to Section 4.5.

1.42 "FDA" means the United States Food and Drug Administration, or a

successor agency thereto.

1.43 "FIELD" means the prophylaxis and/or treatment of PML.

1.44 "IND" means an Investigational New Drug application, Clinical Study

Application, Clinical Trial Exemption, or similar application or

submission for approval to conduct human clinical investigations filed

with or submitted to a Regulatory Authority in conformance with the

requirements of such Regulatory Authority.

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1.45 "IND-ENABLING GLP TOXICOLOGY STUDIES" means genotoxicity, acute

toxicology, safety pharmacology, and sub-chronic toxicology studies in

species that satisfy applicable regulatory requirements using

applicable good laboratory practices which meet the standard necessary

for submission as part of an IND filing with a Regulatory Authority.

1.46 "IN-LICENSES" means collectively, the Alnylam In-Licenses and the

Biogen Idec In-Licenses.

1.47 "JCV" means the human polyomavirus known as JC virus.

1.48 "JCV RNAi THERAPEUTIC" means the [**].

1.49 "JOINT COLLABORATION IP" means, collectively, (a) any improvement,

discovery or Know-How, patentable or otherwise, first identified,

discovered or developed jointly by the Parties or their Affiliates or

others acting on behalf of Biogen Idec and Alnylam under the

Collaboration, and (b) any Patent Rights in the Territory which claim,

cover or relate to such improvements, discoveries or Know-How.

1.50 "KNOW-HOW" means, with respect to an RNAi Therapeutic, all biological

materials and other tangible materials, inventions, practices,

methods, protocols, formulas, knowledge, know-how, trade secrets,

processes, assays, skills, experience, techniques and results of

experimentation and testing, including without limitation

pharmacological, toxicological and pre-clinical and clinical test data

and analytical and quality control data, patentable or otherwise,

which relates to the identification, characterization, optimization,

construction, expression, use or production of such RNAi Therapeutic

and which are reasonably useful or necessary to Discover, Develop,

Manufacture or Commercialize such RNAi Therapeutic in the Field in the

Territory.

1.51 "LINKED PRODUCT" means [**].

1.52 "MAJOR MARKET" means any of the United States, the European Union,

United Kingdom, France, Germany, Italy, Spain or Japan.

1.53 "MANUFACTURING" or "MANUFACTURE" means, as applicable, all activities

associated with the production, manufacture, processing, filling,

finishing, packaging, labeling, shipping, and storage of RNAi

Therapeutics, including process and formulation development, process

validation, stability testing, manufacturing scale-up, pre-clinical,

clinical and commercial manufacture and analytical development,

product characterization, quality assurance and quality control,

whether such activities are conducted by a Party, its Affiliates or a

Third Party contractor of such Party.

1.54 "NDA" means a New Drug Application, Biologics License Application,

Worldwide Marketing Application, Marketing Authorization Application,

Section 510(k) filing or similar application or submission filed with

a Regulatory

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Authority in a country or group of countries to obtain marketing

approval for a biological, pharmaceutical or other therapeutic product

in that country or in that group of countries.

1.55 "NET SALES" means, with respect to the Selected RNAi Therapeutics, the

aggregate gross invoice prices of all units of such Selected RNAi

Therapeutics sold by Biogen Idec and its Related Parties to Third

Parties (other than a Sublicensee of Biogen Idec) after deducting, if

not previously deducted, from the amount invoiced or received (a)

trade and quantity discounts actually given other than early pay cash

discounts; (b) returns, rebates, chargebacks and other allowances

actually given; and (c) retroactive price reductions that are actually

granted.

Notwithstanding the foregoing, in the event a Selected RNAi

Therapeutic is sold in conjunction with another clinically active

therapeutic, prophylactic or diagnostic ingredient or component

(whether packaged together or in the same formulation) (a "Combination

Product"), Net Sales shall be calculated by multiplying the Net Sales

of such Combination Product by a fraction, the numerator of which

shall be the fair market value of the Selected RNAi Therapeutic

included in such Combination Product as if sold separately (determined

in accordance with generally accepted accounting principles), and the

denominator of which shall be the aggregate fair market value of all

the proprietary active ingredients of such Combination Product,

including the Selected RNAi Therapeutic, as if sold separately. In the

event no such separate sales are made by Biogen Idec or its Related

Parties, Net Sales of the Combination Product shall be calculated in a

manner to be negotiated and agreed upon by the Parties, reasonably and

in good faith, prior to any sale of such Combination Product, which

shall be based upon the respective estimated commercial values of the

active components of such Combination Product.

All references to Selected RNAi Therapeutics in this Agreement shall

be deemed to include Combination Product, to the extent applicable.

As provided in Section 5.4.3(b)(ii), Biogen Idec's or any of its

Related Parties' transfer of Selected RNAi Therapeutics to another

Related Party shall not result in any Net Sales, unless such Selected

RNAi Therapeutic is consumed by such Related Party in the course of

its commercial activities.

1.56 "PARTY" or "PARTIES". "Party" means Biogen Idec or Alnylam; "Parties"

means Biogen Idec and Alnylam.

1.57 "PATENT RIGHTS" means all patents (including all reissues, extensions,

substitutions, confirmations, re-registrations, re-examinations,

invalidations, supplementary protection certificates and patents of

addition) and patent applications (including all provisional

applications, continuations, continuations-in-part and divisions).

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1.58 "PML" means progressive multifocal leukoencephalopathy.

1.59 "PRODUCT TRADEMARKS" means the trademark(s), service mark(s),

accompanying logos, trade dress and/or indicia of origin used in

connection with the distribution, marketing, promotion and sale of

each Selected RNAi Therapeutic in the Territory. For purposes of

clarity, the term Product Trademark(s) shall not include, without

limitation, the corporate names and logos of either Party, and shall

include any internet domain names incorporating such Product

Trademarks.

1.60 "REGULATORY APPROVAL" means the approval of the applicable Regulatory

Authority necessary for the marketing and sale of a Selected RNAi

Therapeutic in a particular indication in the Field in a country,

including, where required, separate pricing and/or reimbursement

approvals.

1.61 "REGULATORY AUTHORITY" means any applicable government regulatory

authority involved in granting approvals for the Development,

Manufacturing, or Commercialization of a Selected RNAi Therapeutic in

the Territory, including without limitation the FDA and the EMEA.

1.62 "RELATED PARTY" means Biogen Idec's Affiliates and permitted

Sublicensees, which term does not include wholesale distributors of

Biogen Idec or its Affiliates, who purchase a Selected RNAi

Therapeutic from Biogen Idec or its Affiliates in an arm's length

transaction and who have no other obligation, including without

limitation a reporting obligation, to Biogen Idec or its Affiliates.

1.63 "RNAi THERAPEUTIC" means a therapeutic product containing, comprised

of or based on one or more siRNAs or siRNA derivatives or other

moieties effective in gene function modulation and designed to

modulate the function of particular genes or gene products through RNA

interference.

1.64 "SELECTED RNAi THERAPEUTIC" means the [**].

1.65 "SELECTED RNAi THERAPEUTICS" means, collectively, [**].

1.66 "siRNA" means a double-stranded ribonucleic acid (RNA) composition

designed to act primarily through an RNA interference mechanism that

consists of either (a) two separate oligomers of native or chemically

modified RNA that are hybridized to one another along a substantial

portion of their lengths, or (b) a single oligomer of native or

chemically modified RNA that is hybridized to itself by

self-complementary base-pairing along a substantial portion of its

length to form a hairpin.

1.67 "SUBLICENSEE" means a Third Party to whom a Party grants a sublicense

under any Alnylam Technology (in the case of Biogen Idec), Biogen Idec

Technology (in the case of Alnylam) or Joint Collaboration IP (in the

case of either Party) as permitted under this Agreement.

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1.68 "TERRITORY" means all the countries of the world.

1.69 "THIRD PARTY" means any person or entity other than a Party or any of

its Affiliates.

1.70 "VALID CLAIM" means a claim of: (a) an issued and unexpired Patent

Right, which claim has not been revoked or held unenforceable,

unpatentable or invalid by a decision of a court or other governmental

agency of competent jurisdiction, which is not appealable or has not

been appealed within the time allowed for appeal, and which has not

been abandoned, disclaimed, denied or admitted to be invalid or

unenforceable through reissue, re-examination or disclaimer or

otherwise, or (b) a patent application for a patent included within

the Patent Rights that has been pending less than [**] years from the

earliest date on which such patent application claims priority and

which claim has not been cancelled, withdrawn or abandoned or finally

rejected by an administrative agency action from which no appeal can

be taken.

1.71 ADDITIONAL DEFINITIONS. The following terms have the meanings set

forth in the corresponding Sections of this Agreement:

<TABLE>

<CAPTION>

TERM SECTION

---- -------

<S> <C>

"AGREEMENT TERM" 8.1

"ALNYLAM INDEMNITEES" 9.5.1

"BANKRUPT PARTY" 8.2.2(c)

"BIOGEN IDEC INDEMNITEES" 9.5.2

"BREACHING PARTY" 8.2.1

"CODE" 8.2.2(c)

"COLLABORATION MANAGER" 3.2

"COMBINATION PRODUCT" 1.53

"[**] SUBLICENSE AGREEMENT" 4.5

"DEFENDING PARTY" 6.5.3

"DEVELOPMENT PROGRAM" 2.3

"DISCOVERY PROGRAM" 2.2

"ELAN" 10.2.2

"ESTABLISHED UTILIZATION DATE" 5.3

"FTE" 5.1.1

"FTE RATE" 5.1.1

"GRANTING PARTY" 4.1.5

"INDEMNITEE" 9.5.4

"INFRINGEMENT CLAIM" 6.5.1

"INITIAL ENFORCEMENT RIGHTS PARTY" 6.4.3

"JSC" OR "JOINT STEERING COMMITTEE" 3.1

"JSC CHAIRPERSON" 3.1.2

"LOSSES" 9.5.1

"NON-BANKRUPT PARTY" 8.2.2

"PATENT EXPENSES" 6.3.7

"PROSECUTING PARTY" 6.3.5

</TABLE>

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<TABLE>

<S> <C>

"SECONDARY ENFORCEMENT RIGHTS PARTY" 6.4.3

"SPC" 6.8

"STANFORD AGREEMENT" 4.5

"THIRD PARTY COLLABORATION" 2.6.2

"THIRD PARTY PERFORMERS" 2.6

</TABLE>

ARTICLE 2

COLLABORATION

2.1 OVERVIEW. The Parties shall collaborate in carrying out the

Collaboration with the objective of Discovering and Developing RNAi

Therapeutics directed to JCV in the Field for further

Commercialization by Biogen Idec. Alnylam shall be responsible for the

Discovery of such RNAi Therapeutics, and will present Biogen Idec with

up to [**] RNAi Therapeutics directed to JCV that meet the Development

Criteria and from which Biogen Idec shall select [**] for further

Development under the Collaboration. Subject to the terms of this

Agreement, Biogen Idec will be responsible for the Development of [**]

Selected RNAi Therapeutics and for the further Commercialization of

such Selected RNAi Therapeutics. The Discovery of such RNAi

Therapeutics and the Development of the Selected RNAi Therapeutics

shall be governed by the Annual Work Plan, and the Parties agree to

conduct all their Discovery and Development activities in accordance

with the Annual Work Plan. For the avoidance of doubt, Biogen Idec

shall have the right to Develop and Commercialize [**], but shall have

no obligation to Develop and Commercialize [**].

2.2 DISCOVERY PROGRAM. During the Discovery Term, Alnylam shall use

Commercially Reasonable Efforts to Discover [**] RNAi Therapeutics

directed to JCV that meet the Development Criteria agreed upon by the

JSC and included in the Annual Work Plan (the "Discovery Program").

Alnylam shall from time to time notify the JSC in writing that it

believes that a particular RNAi Therapeutic directed to JCV Discovered

by Alnylam meets the Development Criteria. Upon such notice, the JSC

will promptly meet and Alnylam shall provide the JSC with the data and

information in its possession and Control regarding the applicable

RNAi Therapeutic. Alnylam shall present Biogen Idec with [**] RNAi

Therapeutics in accordance with this Section 2.2. Biogen Idec shall

have the right to select [**] RNAi Therapeutics presented by Alnylam

by written notice to Alnylam. Biogen Idec may make its selection [**]

at any time after Alnylam's presentation of the first RNAi Therapeutic

to the JSC, but Biogen Idec must identify [**] no later than [**] days

after Alnylam's presentation of [**] to the JSC. For avoidance of

doubt, if Biogen Idec selects [**] prior to Alnylam's presentation of

[**] to the JSC, Alnylam will not be relieved of its obligation to

present [**] to the JSC. In the event that Biogen Idec wishes to [**],

Biogen Idec shall do so by written notice to Alnylam no later than

[**] days after Alnylam's presentation to the JSC of [**].

2.3 DEVELOPMENT PROGRAM. Each Party shall use Commercially Reasonable

Efforts to fulfill its obligations to Develop at least one Selected

RNAi Therapeutic as set forth in the Annual Work Plan. Except as

otherwise agreed by the JSC in writing, all activities

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relating to the Development of each Selected RNAi Therapeutic (the

"Development Program") will be set forth in the Annual Work Plan.

2.4 ANNUAL WORK PLAN. The Parties shall prepare and submit for approval by

the JSC the Annual Work Plan for every Contract Year at least [**]

days prior to the commencement of such Contract Year or, in the case

of the first Contract Year only, within [**] days after the Effective

Date. The first Annual Work Plan shall be based on and consistent with

the draft Annual Work Plan attached as Schedule 1.8. The JSC shall

update and amend, as appropriate, the then-current Annual Work Plan

from time to time. All such updates or amendments shall be subject to

approval of the JSC. Each Annual Work Plan shall contain the specific

objectives to be achieved during the Contract Year, the specific

activities to be performed under the Discovery Program and the

Development Program, the timeline for performing such activities and

the Development Criteria. The Annual Work Plan shall allocate

Development tasks between the Parties consistent with their respective

capabilities and with the respective responsibilities of the Parties

as set forth in Sections 2.9 and 2.10 below, and to the extent

possible and scientifically sound, in a manner to maximize the

expeditious and cost-effective Development and Manufacture of each

Selected RNAi Therapeutic. Each Annual Work Plan shall be accompanied

by a budget prepared by the JSC setting forth the projected internal

and external resources and expenses for the Discovery Program and the

Development Program, including quarterly cost detail for the upcoming

calendar year, quarterly forecast of Net Sales, if applicable, for the

upcoming calendar year, and the number of Alnylam FTE's expected to be

required. In addition, the JSC shall approve a long-range budget

covering activities anticipated under Annual Work Plans for each of

the subsequent [**] years. In recognition of the importance of

budgets, each Party shall have the full opportunity to review and

comment on budgets before final approval. The JSC will update the

budget as necessary to reflect approved changes in the Parties'

activities or changes in expected costs for those activities. Such

budget shall be reviewed and approved at least annually by the JSC

pursuant to Section 3.1.4(c).

2.5 [**]. Biogen Idec may at any time, by written notice to the JSC, elect

to [**] the JCV RNAi Therapeutic, and the Parties shall promptly

develop a revised Annual Work Plan to be approved by the JSC.

Effective upon such notice (a) all references in this Agreement to

[**] will automatically be deemed to refer to [**], and (b) all

references to [**] will be deemed to refer to [**].

2.6 THIRD PARTIES.

2.6.1 In General. The Parties shall be entitled to utilize the

services of Third Parties, including Third Party contract

research organizations and service providers, and to collaborate

with Third Parties ("Third Party Performers"), to perform their

respective Discovery, Development and Manufacturing activities;

provided that each Party shall remain at all times fully liable

for its respective responsibilities under this Agreement and the

Annual Work Plan. Except as expressly permitted under Section

2.6.2, neither Party shall use Third Party Performers to conduct

part or all of its obligations under this Agreement or the

Collaboration unless the contracting or collaborating party's

agreement with the Third Party Performer

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provides the non-contracting or non-collaborating Party with the

same rights under this Agreement as if the contracting or

collaborating Party had done the work itself, and any such Third

Party agreement shall include confidentiality and non-use

provisions which are no less stringent than those set forth in

Article 7 of this Agreement.

2.6.2 Third Party Collaborations. In the event that, despite good

faith efforts, the contracting Party is unable to enter into an

agreement with a Third Party Performer that meets the

requirements of the second sentence of Section 2.6.1, such

activities will be termed a "Third Party Collaboration." If any

Third Party Collaborations are contemplated in connection with

the Collaboration, such Third Party Collaborations will be

approved in advance by the JSC, and the Annual Work Plan shall be

amended to include such approved Third Party Collaborations. The

Parties shall use good faith efforts to ensure that, to the

extent possible, all such Third Party Collaborations shall

provide that any and all data and results, discoveries and

inventions, whether patentable or not, arising out of the Third

Party Collaboration may be used by bona fide collaborators of the

Party entering into the Third Party Collaboration agreement. In

addition, a Party entering into any such Third Party

Collaboration shall use reasonable efforts to obtain a right to

sublicense to the other Party and its Affiliates and Sublicensees

any intellectual property arising out of the Third Party

Collaboration to the extent necessary for the other Party to

perform its obligations under this Agreement. Except as expressly

stated in this Section 2.6.2, all Third Party Collaborations must

meet the requirements of Section 2.6.1.

2.7 RECORDS. Each Party shall maintain scientific records, in sufficient

detail and in good scientific manner appropriate for patent and

regulatory purposes, which shall fully and properly reflect all work

done and results achieved in the performance of the Collaboration by

such Party. Each Party shall have the right, during normal business

hours and upon reasonable notice, to inspect and copy (or request the

other Party to copy) all records of the other Party maintained in

connection with the work done and results achieved in the performance

of the Collaboration, but solely to the extent access to such records

is necessary for a Party to exercise its rights under this Agreement.

All such records and the information disclosed therein shall be

maintained in confidence by the recipient in accordance with Article

7.

2.8 DEVELOPMENT MATERIAL TRANSFER. In order to facilitate the

Collaboration, either Party may provide to the other Party certain

Development Materials Controlled by the supplying Party (other than

under this Agreement) for use by the other Party in furtherance of the

Collaboration. Except as otherwise provided under this Agreement or

explicitly authorized in writing by the supplying Party, all such

Development Materials delivered to the other Party shall remain the

sole property of the supplying Party, shall be used only in

furtherance of the Collaboration and solely under the control of the

other Party and its Affiliates, shall not be used or delivered to or

for the benefit of any Third Party without the prior written consent

of the supplying Party, and shall not be used in research or testing

involving human subjects. The Development Materials supplied under

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this Section 2.8 must be used with prudence and appropriate caution in

any experimental work, since not all of their characteristics may be

known. THE DEVELOPMENT MATERIALS ARE PROVIDED "AS IS" AND WITHOUT ANY

REPRESENTATION OR WARRANTY, EXPRESS OR IMPLIED, INCLUDING WITHOUT

LIMITATION ANY IMPLIED WARRANTY OF MERCHANTABILITY OR OF FITNESS FOR

ANY PARTICULAR PURPOSE OR, SAVE AS EXPLICITLY PROVIDED IN THIS

AGREEMENT, ANY WARRANTY THAT THE USE OF THE MATERIALS WILL NOT

INFRINGE OR VIOLATE ANY PATENT OR OTHER PROPRIETARY RIGHTS OF ANY

THIRD PARTY.

2.9 REGULATORY MATTERS.

2.9.1 Coordination. Biogen Idec shall oversee, monitor, coordinate,

file and hold in its name all regulatory actions, communications

and filings with and submissions, including filings and

submissions of supplements and amendments thereto, to the

applicable Regulatory Authorities with respect to the Selected

RNAi Therapeutics; provided, however, that Biogen Idec shall

consult with Alnylam regarding [**].

2.9.2 Regulatory Meetings and Correspondence. Biogen Idec shall be

responsible for interfacing, corresponding and meeting with the

applicable Regulatory Authorities with respect to the Selected

RNAi Therapeutics. Upon the request of Biogen Idec, Alnylam shall

[**] the applicable Regulatory Authorities with respect to each

Selected RNAi Therapeutic.

2.9.3 Review of Correspondence. To the extent practicable, Biogen Idec

shall provide Alnylam with [**] the applicable Regulatory

Authorities pertaining to each Selected RNAi Therapeutic, [**],

and, [**] Biogen Idec, Alnylam shall [**]. Biogen Idec shall

provide to Alnylam as soon as reasonably practicable [**] such

Regulatory Authorities pertaining to each Selected RNAi

Therapeutic (including without limitation [**]).

2.9.4 Assistance. Each Party shall cooperate with the other Party to

provide all reasonable assistance and take all actions reasonably

requested by the other Party that are necessary or desirable to

enable the other Party to comply with any law or regulation

applicable to the Selected RNAi Therapeutics or the

Collaboration, including, but not limited to, reporting adverse

drug experiences (and serious adverse drug experiences) to the

applicable Regulatory Authorities.

2.10 MANUFACTURE AND SUPPLY.

2.10.1 Pre-Clinical and Clinical Supply. During the Collaboration

Term, Alnylam will use Commercially Reasonable Efforts to

Manufacture and supply the Parties' requirements of the Selected

RNAi Therapeutics for pre-clinical and clinical Discovery and

Development purposes, including those requirements for

manufacture and supply of Selected RNAi Therapeutics for

administration outside of formal clinical trials in the manner

described in Section 1.38(a). Biogen Idec

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will pay Alnylam for the quantities of Selected RNAi Therapeutics

supplied by Alnylam hereunder in accordance with Section 5.1.2.

Within [**] after the Effective Date, the Parties shall enter

into a supply agreement reasonably acceptable to both Parties

pursuant to which Alnylam will supply the Selected RNAi

Therapeutics to Biogen Idec. The aforementioned supply agreement

shall provide that (a) [**] Manufacturing each Selected RNAi

Therapeutic [**]; (b) any such [**] will be subject to [**]; and

(c) Biogen Idec shall [**] Selected RNAi Therapeutics for

pre-clinical and clinical Discovery and Development. Such supply

agreement will also explicitly provide that [**].

2.10.2 Commercial Supply. Biogen Idec shall be responsible for the

Manufacture and supply of the Selected RNAi Therapeutics after

the Collaboration Term and for commercial sale throughout the

Territory. Alnylam shall provide [**]; provided that (a) any such

[**]; and (b) [**] of Alnylam.

2.11 COMMERCIALIZATION. Subject to the terms of this Agreement, Biogen Idec

shall be solely responsible for all Commercialization activities

relating to the Selected RNAi Therapeutics and shall bear one hundred

percent (100%) of all expenses for the Commercialization of such

Selected RNAi Therapeutics. Biogen Idec shall use Commercially

Reasonable Efforts to Commercialize the JCV RNAi Therapeutic in the

Major Markets.

ARTICLE 3

COLLABORATION MANAGEMENT

3.1 JOINT STEERING COMMITTEE. As soon as practicable after the Effective

Date, the Parties shall establish a committee to facilitate the

Collaboration (the "Joint Steering Committee" or "JSC") as follows:

3.1.1 Composition of the JSC. The Collaboration shall be conducted

under the direction of a JSC comprised of three (3)

representatives of Alnylam and three (3) representatives of

Biogen Idec. Each Party shall appoint its respective

representatives to the JSC from time to time, and may substitute

one or more of its representatives, in its sole discretion,

effective upon notice to the other Party of such change. Each

Party shall have at least one JSC representative who is a senior

employee (director level or above), and all JSC representatives

shall have appropriate research, preclinical, manufacturing,

clinical development or commercialization expertise and ongoing

familiarity with the Collaboration. Additional representatives or

consultants may from time to time, by mutual consent of the

Parties, be invited to attend JSC meetings, subject to such

representatives' and consultants' written agreement to comply

with the requirements of Article 7. Each Party shall bear its own

expenses relating to attendance at such meetings by its

representatives.

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3.1.2 JSC Chairperson. The "JSC Chairperson" shall be a representative

of Biogen Idec. The JSC Chairperson's responsibilities shall

include (a) scheduling meetings at least once per Contract

Quarter, but more frequently if the JSC determines it necessary;

(b) setting agendas for meetings with solicited input from other

members; (c) confirming and delivering minutes to the JSC for

review and final approval; and (d) conducting effective meetings,

including ensuring that objectives for each meeting are set and

achieved.

3.1.3 Meetings. The JSC shall meet in accordance with a schedule

established by mutual written agreement of the Parties, but no

less frequently than once per Contract Quarter, with the location

for such meetings alternating between Alnylam and Biogen Idec

facilities (or such other locations as are determined by the

JSC). Alternatively, the JSC may meet by means of teleconference,

videoconference or other similar communications equipment, but at

least two meetings per year shall be conducted in person.

3.1.4 JSC Responsibilities. The JSC shall have the following

responsibilities with respect to the Collaboration:

(a) determining the overall Discovery and Development strategy

for each Selected RNAi Therapeutic in the Territory;

(b) reviewing for approval the initial Annual Work Plan

(including without limitation the Development Criteria)

within [**] days after the Effective Date, with appropriate

input from Alnylam and Biogen Idec senior management;

(c) reviewing for approval (i) the annual update to the Annual

Work Plan and the related budget described in Section 2.4,

and (ii) any modifications to such Annual Work Plan and

related budget, in each case within [**] days of each

submission to the JSC;

(d) determining each Party's responsibilities under the Annual

Work Plan consistent with Section 2.4; provided, however,

that the JSC may not, without Alnylam's consent, assign

Alnylam any responsibilities under the Annual Work Plan for

which Alnylam does not at the time already have sufficient

internal expertise and resources;

(e) facilitating the transfer of Know-How and Confidential

Information between the Parties for purposes of conducting

the Annual Work Plan;

(f) regularly assessing the progress of the Parties in their

conduct of the Annual Work Plan and against the timelines

and budgets contained therein, reviewing relevant data, and

considering issues of priority;

(g) reviewing for approval, within the Parties' regular business

cycles, but no later than [**] days after a proposal is made

to the JSC by either Party, the

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initiation of IND-Enabling Toxicology Studies and the

submission of an IND with respect to each Selected RNAi

Therapeutic; and

(h) performing such other activities as are contemplated under

this Agreement and that the Parties mutually agree shall be

the responsibility of the JSC.

3.2 APPOINTMENT OF SUBCOMMITTEES, PROJECT TEAMS AND COLLABORATION

MANAGERS. The JSC shall be empowered to create such subcommittees of

itself and additional project teams as it may deem appropriate or

necessary. Each such subcommittee and project team shall report to the

JSC, which shall have authority to approve or reject recommendations

or actions proposed thereby subject to the terms of this Agreement.

Each Party shall also designate a "Collaboration Manager." The

Collaboration Managers will be responsible for the day-to-day

coordination of the Collaboration and will serve to facilitate

communication between the Parties. Each Party may change its

designated Collaboration Manager from time to time upon written notice

to the other Party.

3.3 REPORTS AND MINUTES. Each Party will provide the members of the JSC

with written copies of all materials they intend to present at the JSC

meeting. The JSC may also request at any time specific data or

information related to Development activities or that a written report

be prepared in advance of any meeting summarizing certain material

data and information arising out of the conduct of the Development

activities and the Party or appropriate committee to whom such request

is made shall promptly provide to the other Party or JSC such report,

data or information. A secretary shall be appointed for each meeting

and shall prepare minutes of the meeting, which shall provide a

description in reasonable detail of the discussions held at the

meeting and a list of any actions, decisions or determinations

approved by the JSC.

3.4 DECISION-MAKING AND DISPUTE RESOLUTION.

3.4.1 Voting. With respect to decisions of the JSC, the

representatives of each Party shall have collectively one vote on

behalf of such Party. For each meeting of the JSC, at least two

(2) representatives of each Party shall constitute a quorum.

Action on any matter may be taken at a meeting, by

teleconference, videoconference or by written agreement.

3.4.2 Decision-Making. The JSC shall operate by consensus, subject to

the dispute resolution process set forth in Section 3.4.3 below.

3.4.3 Dispute Resolution. The JSC shall attempt to resolve any and all

disputes relating to the Collaboration by unanimous consensus. In

the event the JSC is unable to reach a unanimous consensus with

respect to any such dispute, then the following dispute

resolution provisions shall apply.

(a) With respect to any dispute over which [**] except those

disputes related to [**]; provided, however, that [**] shall

have the right to propose [**], for good faith consideration

by [**], and if [**], then [**] shall [**]. Notwithstanding

anything to the contrary, [**] may not, without

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Alnylam's consent, increase Alnylam's obligation to provide

FTE's in performance of Alnylam's activities under the

Annual Work Plan by more than [**] percent ([**]%) of the

number of FTE's required in the preceding year.

(b) Notwithstanding anything else contained herein,

Commercialization activities shall not be the responsibility

of the JSC and shall be subject to Biogen Idec's final

decision-making authority.

(c) With respect to any dispute concerning [**] the dispute

shall be [**] as described in this paragraph. If the dispute

cannot be resolved [**], then within [**] days after

[**]shall be [**] in good faith as soon as is practicable

but in no event [**]. Such resolution, if any, by [**] shall

be final and binding on the Parties. If the [**] shall have

[**] decision-making authority.

(d) With respect to all other disputes between the Parties

regarding the interpretation, construction or application of

this Agreement, the dispute shall be [**] for review as

described in this paragraph. If the dispute cannot be

resolved [**], then within [**] days after [**] shall be

[**] as soon as is practicable but in no event [**]. Such

resolution, if any, by [**] shall be final and binding on

the Parties. If the [**], each Party will be free to pursue

all rights available to it under law or equity.

3.5 DISSOLUTION OF JSC. The JSC shall be dissolved at the end of the

Collaboration Term; provided that Alnylam's participation in the JSC

after the fifth (5th) anniversary of the Effective Date will be at

Alnylam's sole option.

ARTICLE 4

LICENSES

4.1 LICENSE GRANTS. The following Licenses are granted as of the Effective

Date:

4.1.1 Discovery License. Subject to the terms and conditions of this

Agreement, Biogen Idec hereby grants Alnylam a co-exclusive (with

Biogen Idec) royalty-free license under Biogen Idec Technology to

Discover RNAi Therapeutics directed to JCV and to otherwise

conduct the Discovery Program in the Field, in each case to the

extent necessary for Alnylam to conduct its activities under the

Annual Work Plan. Subject to the terms and conditions of this

Agreement, Alnylam hereby grants Biogen Idec a co-exclusive (with

Alnylam), royalty-free license under Alnylam Technology to

Discover RNAi Therapeutics directed to JCV and to otherwise

conduct the Discovery Program in the Field, in each case to the

extent necessary for Biogen Idec to conduct its activities under

the Annual Work Plan.

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4.1.2 Development Licenses. Subject to the terms and conditions of

this Agreement, Alnylam hereby grants Biogen Idec a co-exclusive

(with Alnylam), royalty-free license under Alnylam Technology to

Develop the Selected RNAi Therapeutics in the Field in the

Territory, to the extent necessary for Biogen Idec to conduct its

activities under the Annual Work Plan. Subject to the terms and

conditions of this Agreement, Biogen Idec hereby grants Alnylam a

co-exclusive (with Biogen Idec), royalty-free license under

Biogen Idec Technology to Develop the Selected RNAi Therapeutics

in the Field in the Territory, to the extent necessary for

Alnylam to conduct its activities under the Annual Work Plan.

4.1.3 Commercialization License. Subject to the terms and conditions

of this Agreement, Alnylam hereby grants Biogen Idec an

exclusive, royalty-bearing license under Alnylam Technology to

Commercialize the Selected RNAi Therapeutics in the Field in the

Territory.

4.1.4 Manufacturing Licenses. Subject to the terms and conditions of

this Agreement, only as permitted and solely for the purposes set

forth in Section 2.10.2, Alnylam hereby grants Biogen Idec a

non-exclusive, fully-paid, royalty-free license under Alnylam

Technology to Manufacture the Selected RNAi Therapeutics for the

Territory. Subject to the terms and conditions of this Agreement,

only as permitted and solely for the purposes set forth in

Section 2.10.1, Biogen Idec hereby grants Alnylam a non-exclusive

license under Biogen Idec Technology to Manufacture the Selected

RNAi Therapeutics.

4.1.5 Blocking RNAi Technology License. Biogen Idec hereby grants

Alnylam a non-exclusive, royalty-free license, with the right to

grant sublicenses, under any Blocking RNAi Technology for the

purpose of research, development, manufacture, use, import,

distribution, marketing or sale of RNAi Therapeutics outside the

Field.

4.2 SUBLICENSES AND LICENSES OF JOINT COLLABORATION IP. The licenses in

Section 4.1 each includes the right to grant sublicenses and licenses

as provided in this Section 4.2 below.

4.2.1 Affiliates. Each Party shall be entitled to grant sublicenses of

its rights under this Agreement (and licenses under any Joint

Collaboration IP) to any of its Affiliates for so long as such

entity remains an Affiliate.

4.2.2 Academic Collaborators and Service Companies. Each Party shall

be entitled to grant sublicenses of its rights under Sections

4.1.1 and 4.1.2 (and licenses under any Joint Collaboration IP)

in connection with its activities under the Annual Work Plan to

academic collaborators, and contract service organizations, that

in each case are subject to and fulfill the requirements of

Section 2.6, to perform its obligations under such Annual Work

Plan.

4.2.3 Manufacturing Sublicenses. Subject to the provisions of Sections

2.10.1 and 2.10.2 regarding approval of subcontractors, each

Party entitled to Manufacture RNAi Therapeutics under the terms

and conditions of this Agreement shall be

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entitled to grant sublicenses of its rights under this Agreement

(and licenses under any Joint Collaboration IP) to Third Parties

to Manufacture such RNAi Therapeutics; provided, that such Party

shall remain primarily responsible with respect to such

sublicense.

4.2.4 Terms. Each sublicense granted by a Party pursuant to Section

4.2.2 or Section 4.2.3 shall be subject and subordinate to the

terms and conditions of this Agreement and shall contain terms

and conditions consistent with those in this Agreement.

Agreements with any Commercializing Sublicensee shall contain the

following provisions: (a) a requirement that such Sublicensee

submit applicable sales or other reports consistent with those

required hereunder; (b) an audit requirement similar to the

requirement set forth in Section 5.5; and (c) a requirement that

such Sublicensee comply with the confidentiality and non-use

provisions of Article 7 with respect to both Parties'

Confidential Information.

4.2.5 Liability. Each Party shall at all times be responsible for the

performance of its Sublicensees under this Agreement.

4.2.6 Sublicense Survival. Any sublicense by a Party shall be subject

to the provisions of this Agreement and shall survive termination

of the licenses or other rights granted to such Party under this

Agreement in accordance with this Section 4 and be assumed by the

other Party as long as (a) the Sublicensee is not then in breach

of its sublicense agreement, (b) the Sublicensee agrees in

writing to be bound to the non-sublicensing Party as a licensor

under the terms and conditions of the sublicense agreement, and

(iii) the Sublicensee agrees in writing that in no event shall

the non-sublicensing Party assume any obligations or liabilities,

or be under any obligation or requirement of performance, under

any such sublicense extending beyond such Party's obligations and

liabilities under this Agreement.

4.3 JOINT COLLABORATION IP. Subject to the rights granted each Party under

this Agreement, each Party shall have the right to use, sell, keep,

license or assign its interest in Joint Collaboration IP and otherwise

undertake all activities a sole owner might undertake with respect to

such Joint Collaboration IP without the consent of and without

accounting to the other Party.

4.4 IN-LICENSES. All licenses and other rights granted Biogen Idec under

this Article 4 are subject to the rights and obligations of Alnylam

under the Alnylam In-Licenses. All licenses and other rights granted

Alnylam under this Article 4 are subject to the rights and obligations

of Biogen Idec under the Biogen Idec In-Licenses.

4.5 CERTAIN PATENT RIGHTS. Notwithstanding anything to the contrary

herein, the licenses to Alnylam Patent Rights hereunder initially

shall not include licenses to Patent Rights licensed by Alnylam or its

Affiliates under the [**]; provided that if any such Patent Rights

in-licensed by Alnylam become issued Patent Rights that Cover a

Selected RNAi Therapeutic, Alnylam shall so notify Biogen Idec in

writing, and Biogen Idec shall have the option of expanding its

licenses to Alnylam Patent Rights hereunder to include such issued

Patent Rights by notifying Alnylam of such election in writing. Upon

such

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election, the [**] Agreement shall be deemed an Existing Alnylam

In-License and Schedule 1.41 shall be amended accordingly without any

further consideration due from Biogen Idec to Alnylam. Further,

notwithstanding anything to the contrary herein, the licenses to

Alnylam Patent Rights hereunder shall not include licenses to Patent

Rights licensed by Alnylam or its Affiliates under the License

Agreement between [**]. The Parties shall simultaneously with the

execution of this Agreement enter into an agreement substantially in

the form set forth in Schedule 4.5 (the "[**] Sublicense Agreement").

4.6 TERMINATION OF CERTAIN LICENSE RIGHTS. Notwithstanding anything to the

contrary in this Agreement, in the event that Biogen Idec imposes any

conditions of access to or treatment with Selected RNAi Therapeutic by

patients who have been treated using products from Third Parties that

compete directly with Linked Products, then all rights and licenses

granted to Biogen Idec with respect to [**], whichever is less

advanced in the Development and Commercialization process, shall

terminate and revert to Alnylam.

4.7 NO OTHER RIGHTS. Except as otherwise expressly provided in this

Agreement, under no circumstances shall a Party hereto, as a result of

this Agreement, obtain any ownership interest or other right in any

Know-How or Patent Rights of the other Party, including items owned,

controlled or developed by the other Party, or provided by the other

Party to the receiving Party at any time pursuant to this Agreement.

ARTICLE 5

FINANCIAL PROVISIONS

5.1 DISCOVERY, DEVELOPMENT AND MANUFACTURING FUNDING.

5.1.1 Discovery and Development Funding. Biogen Idec will reimburse

Alnylam for all internal and out-of-pocket costs and expenses

incurred by Alnylam during the Collaboration Term in accordance

with the Annual Work Plan, for [**]. The costs of Alnylam's

internal personnel engaged in such efforts shall be determined by

multiplying the number of full time equivalent person years

("FTEs") allocated by Alnylam to the Collaboration during the

relevant time period, by the FTE Rate. The "FTE Rate" for work

performed by Alnylam FTEs will be $[**] per FTE, which amount may

be increased or decreased on an annual basis as mutually agreed

by the Parties, but in no event more than [**] percent ([**]%)

per Contract Year.

5.1.2 Manufacturing Funding. Biogen Idec will pay Alnylam [**] for

quantities of each Selected RNAi Therapeutic supplied by Alnylam

to Biogen Idec pursuant to Section 2.10.1 that is equal to [**]

as set forth in [**].

5.2 MILESTONES.

5.2.1 Upfront Payment. No later than ten (10) Business Days after the

Effective Date, Biogen Idec wi