ASSET PURCHASE AGREEMENT

Exhibit 10.1

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ASSET PURCHASE AGREEMENT

THIS ASSET PURCHASE AGREEMENT (this “ Agreement ”), dated as of August 15, 2007 (the “ Agreement Date ”), is made by and between CELL THERAPEUTICS, INC., a Washington corporation (“ Buyer ”), and BIOGEN IDEC INC., a Delaware corporation (“ Seller ”).

WHEREAS, Seller and certain of Seller’s Affiliates (as defined below) manufacture, market, sell and distribute in the United States the Product (as defined below);

WHEREAS, Seller desires to sell to Buyer, and Buyer desires to purchase from Seller, certain Purchased Assets (as defined below) related to the Product in the United States, all upon the terms and subject to the conditions set forth in this Agreement; and

WHEREAS, in connection with the purchase and sale of the Purchased Assets, Buyer and Seller desire to enter into certain arrangements with respect to the Purchased Assets in the United States as expressly contemplated by this Agreement.

NOW, THEREFORE, in consideration of the premises and mutual covenants contained herein and for other good and valuable consideration, the receipt and adequacy of which are hereby acknowledged, Buyer and Seller agree as follows:

ARTICLE I

DEFINITIONS

Section 1.1 Definitions . As used in this Agreement, the following terms shall have the meanings ascribed to them below:

“ Action ” means any claim, dispute, action (including any action seeking injunctive or other equitable relief), arbitration, mediation, litigation, proceeding, suit or governmental investigation and any appeal therefrom.

“ Affiliate ” means, with respect to any Person, any other Person that directly or indirectly Controls, is Controlled by or is under common Control with such first Person. A Person will be deemed to “ Control ” another Person if such first Person has the power to direct or cause the direction of the management and policies of such other Person, whether through ownership of securities, by contract or otherwise.

“ Agreement ” has the meaning set forth in the introductory paragraph.

“ Agreement Date ” has the meaning set forth in the introductory paragraph.

“ Assigned Contracts ” mean the Contracts listed on Schedule 5.8 , but only to the extent noted on Schedule 5.8 ( i.e. , as to certain listed Contracts, not all rights and obligations are being assigned – as more fully noted on Schedule 5.8 ); provided , however , that notwithstanding any provision herein to the contrary, where the consent of any other Person is necessary (as identified on Schedule 5.8 ) in order for any interest of Seller or any of Seller’s Affiliates in any such Contract to be assigned to Buyer, such Contract shall not be deemed to be an Assigned Contract unless and until either (i) such consent is obtained or (ii) Buyer and Seller separately agree ( i.e. , outside of this Agreement and the arrangements contemplated hereby, including the Contract Assignment and Assumption Agreement) to include such Contract as an Assigned Contract.

“ Assumed Contractual Obligations ” mean the obligations of Seller or any of Seller’s Affiliates under the Assigned Contracts from and after the Closing Date; provided , however , that Assumed Contractual Obligations shall not include any obligations that arise due to a breach or default under the Assigned Contracts prior to Closing.

“ Biosimilar Product ” means a biosimilar product approved by the FDA based upon reference to the prior approval of the Product (and the clinical data supporting such approval) to which such biosimilar product is therapeutically equivalent.

“ Books and Records ” mean all pricing lists, customer lists, material customer correspondence and related material books and records used solely and specifically with respect to the Product in the United States by Seller or any of Seller’s Affiliates, but in each instance only to the extent in existence as of the Closing Date and readily within the possession or control of Seller or any of Seller’s Affiliates.

“ Business Day ” means any day other than a Saturday, Sunday or other day on which banks in the City of New York are permitted or required to close by any Governmental Rule.

“ Buyer ” has the meaning set forth in the introductory paragraph.

“ Buyer Indemnified Parties ” has the meaning set forth in Section 12.2(a) .

“ Closing ” has the meaning set forth in Section 4.1 .

“ Closing Date ” has the meaning set forth in Section 4.1 .

“ CMS-HHS ” means the Centers for Medicare & Medicaid Service of the United States Department of Health and Human Services.

“ Commercialization ” means any (i) sales of the Product or Finished US Goods, or any portion of any of the foregoing, for ultimate use in the United States or (ii) other commercial activities related to the Product in the United States.

“ Confidential Information ” means information which is confidential or proprietary to the Disclosing Party, including know-how, scientific information, the terms of this Agreement or any other Transaction Document, clinical data, efficacy and safety data, adverse event information, formulas, methods and processes, specifications, pricing information (including

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discounts, rebates and other price adjustments) and other terms and conditions of sales, customer information, business plans and all other intellectual property; provided , however , that Confidential Information shall not include the following: (i) information of a Disclosing Party that is known to a Receiving Party or its Affiliates prior to the time of disclosure to it, to the extent evidenced by written records or other competent proof, unless a proprietary interest in such information is transferred to the Disclosing Party pursuant to this Agreement or any other Transaction Document; (ii) information that is independently developed by employees, agents or independent contractors of a Receiving Party or its Affiliates without reference to or reliance upon the information furnished by the Disclosing Party, as evidenced by written records or other competent proof, unless a proprietary interest in such information is transferred to the Disclosing Party pursuant to this Agreement or any other Transaction Document; (iii) information disclosed to a Receiving Party or its Affiliates by a third Person that has a right to make such disclosure; or (iv) any other information that is or becomes part of the public domain through no fault or negligence of the Receiving Party.

“ Confidentiality Agreement ” means that certain confidentiality agreement, dated as of April 26, 2007, by and between Buyer and Seller.

“ Contracts ” mean contracts, leases, indentures, agreements, notes, bonds, loans, instruments, conditional sale contracts, mortgages, licenses, purchase orders and all other legally binding arrangements or commitments, whether written or oral or in existence on the Agreement Date or subsequently entered into, including all amendments thereto.

“ Contract Assignment and Assumption Agreement ” means the assignment and assumption agreement to be executed and delivered by Buyer and Seller at the Closing substantially in the form of Exhibit A .

“ Customer Orders ” mean orders for Finished US Goods from customers of Seller or any of Seller’s Affiliates in the United States.

“ Disclosing Party ” has the meaning set forth in Section 9.6(a) .

“ Disclosure Schedule ” means the Disclosure Schedule delivered by Seller to Buyer concurrently with delivering this Agreement.

“ Disputes ” has the meaning set forth in Section 5.10(d) .

“ Encumbrance ” means any mortgage, charge, lien, security interest, easement, right of way, pledge or any similar encumbrance of any nature whatsoever.

“ Excluded Assets ” has the meaning set forth in Section 2.2(b) .

“ Excluded Intellectual Property ” means: (i) the Licensed Patents; (ii) the Sublicensed Patent Rights; (iii) the Sublicensed Patent Rights Agreements; (iv) the Seller Trade Dress; (v) the Seller Trademarks; (vi) any computer programs and software; and (vii) any other copyrights, Patents, trade dress, Trademarks or other intellectual property that does not relate solely and specifically to the development, manufacture, marketing, sale or distribution of the Product (except as expressly included in the Product Intellectual Property).

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

“ FFDCA ” means the Federal Food, Drug, and Cosmetic Act of 1938, as amended.

“ Finished US Goods ” mean kits containing the Product labeled and ready for distribution and sale to end-users in the United States, as contemplated by the definition for such term in the Supply Agreement; provided , however , that for purposes of this Agreement, such term shall also include any single such kit containing one of the constituent parts of the Product.

“ General Assignment and Assumption Agreement ” means the assignment and assumption agreement to be executed and delivered by Buyer and Seller at the Closing substantially in the form of Exhibit B .

“ General Assignment and Bill of Sale ” means the assignment and bill of sale to be executed and delivered by Seller at the Closing substantially in the form of Exhibit C .

“ Governmental Entity ” means any court, administrative agency or commission or other governmental or regulatory authority or instrumentality of applicable jurisdiction, whether domestic or foreign.

“ Governmental Rule ” means any applicable law, judgment, order, award, decree, statute, ordinance, rule or regulation issued or promulgated by any Governmental Entity.

“ HSR Act ” means the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended.

“ Indemnified Party ” has the meaning set forth in Section 12.6(a) .

“ Indemnifying Party ” has the meaning set forth in Section 12.6(a) .

“ Integrity Agreement ” means a corporate integrity agreement to be entered into by and between Buyer and OIG-HHS.

“ Knowledge of Seller ” means the actual knowledge of Faheem Hasnain.

“ Liabilities ” mean any and all debts, liabilities and obligations, whether accrued or fixed, absolute or contingent, matured or unmatured or determined or determinable, including those arising under any Governmental Rule, Contract or otherwise.

“ License Agreement ” means the license agreement to be executed and delivered by Buyer and Seller at the Closing substantially in the form of Exhibit D .

“ License-Back Agreement ” means the license-back agreement to be executed and delivered by Buyer and Seller at the Closing substantially in the form of Exhibit E .

“ Licensed Patents ” mean the Patents listed on Schedule 5.10 .

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“ Losses ” mean any and all damages, losses, Taxes, Liabilities, claims, judgments, penalties, costs and expenses, including reasonable attorneys’ fees and litigation expenses.

“ Manufacturing Confidential Information ” means Confidential Information relating to the manufacture or supply of the Product or Finished US Goods, or any portion of any of the foregoing, including Product Manufacturing Technology (as defined in the Supply Agreement), that is (i) disclosed to Buyer or any of its Affiliates by Seller or any of its Affiliates (including through observation by Buyer or any of its Affiliates) and (ii) maintained as confidential by Seller and its Affiliates prior to such disclosure; provided , however , that Manufacturing Confidential Information shall not include (x) information disclosed to Buyer or any of its Affiliates by a third Person (excluding, for this purpose, Seller or any of its Affiliates) that has a right to make such disclosure or (y) any other information that is or becomes part of the public domain through no fault or negligence of Buyer or any of its Affiliates or any third party manufacturer engaged by Buyer or any of its Affiliates.

“ Material Adverse Effect ” means a change, circumstance or effect that has had a materially adverse effect on the Purchased Assets taken as a whole, but excluding any change, circumstance or effect caused by or relating to: (i) changes in conditions generally affecting (A) the healthcare or biotechnology industry or (B) the United States or world economy or securities markets; (ii) the execution or announcement of this Agreement or the consummation of the transactions contemplated hereby, including any loss of employees, suppliers or customers resulting therefrom; (iii) changes in any Governmental Rule or generally accepted accounting principles or interpretations thereof; (iv) any act of civil unrest, war or terrorism; or (v) a decline in revenues of or orders for the Product.

“ Milestone Events ” has the meaning set forth in Section 3.3 .

“ Milestone Payments ” has the meaning set forth in Section 3.3 .

“ NDC Number ” means either of the national drug code numbers associated with the Product as of the Agreement Date, No. 64406-104-04 or No. 64406-103-03.

“ OIG-HHS ” means the Office of Inspector General of the United States Department of Health and Human Services.

“ Patent Assignment ” means the patent assignment to be executed and delivered by Seller at the Closing substantially in the form of Exhibit F .

“ Patents ” mean all United States patents and patent applications, including reissues, divisions, continuations, continuations-in-part and extensions thereof and reexamination certificates therefor.

“ Person ” means any individual, corporation, partnership, limited liability company, joint venture, trust, business association, organization, Governmental Entity or other entity.

“ Post-BLA Clinical Trial Records ” mean all final reports and other material records for clinical studies with respect to the Product in the United States, but in each instance only to the

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extent: (i) in existence as of the Closing Date; (ii) readily within the possession of, and controlled and transferable by, Seller or any of Seller’s Affiliates; and (iii) relating to any study that commenced after February 19, 2002.

“ Post-Closing Liabilities ” has the meaning set forth in Section 2.3(a) .

“ Pre-Closing Liabilities ” has the meaning set forth in Section 2.3(b) .

“ Product ” means the pharmaceutical product currently marketed and sold as ZEVALIN ^® (Ibritumomab Tiuxetan), consisting of Indium-111 Ibritumomab Tiuxetan and Yttrium-90 Ibritumomab Tiuxetan, as such term is more particularly defined in the Supply Agreement.

“ Product Domain Names ” mean the Internet domain names listed on Schedule 5.10 .

“ Product Intellectual Property ” means: (i) the Product Domain Names; (ii) the Product Patents; (iii) the Product Trade Dress; and (iv) the Product Trademarks.

“ Product Marketing Materials ” mean all sales training, marketing and other promotional materials used solely and specifically with respect to the Product in the United States by Seller or any of Seller’s Affiliates, but in each instance only to the extent in existence as of the Closing Date and readily within the possession or control of Seller or any of Seller’s Affiliates.

“ Product Patents ” mean the United States patents and patent applications listed on Schedule 5.10 , including reissues, divisions, continuations, continuations-in-part and extensions thereof and reexamination certificates therefor.

“ Product Trade Dress ” means the current trade dress of the Product, but excluding Seller Trade Dress.

“ Product Trademarks ” mean the Trademarks listed on Schedule 5.10 .

“ Product Toll-Free Number ” means the 1-866-298-8433 telephone number.

“ Purchase Price ” has the meaning set forth in Section 3.1 .

“ Purchased Assets ” has the meaning set forth in Section 2.2(a) .

“ Rebates ” mean all payments, rebates, reimbursements, administrative fees or chargebacks due (i) under any state or federal program in the United States (including Medicaid) or (ii) to customers in the United States under any private party managed care Contract or under any other Contract or program of any nature whatsoever with private Persons.

“ Receiving Party ” has the meaning set forth in Section 9.6(a) .

“ Regulatory Applications/Approvals ” mean Biologics License Application No. 125019, as initially approved by the FDA on February 19, 2002, and all supplements,

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amendments and revisions thereto, whether approved or not, together with all supporting documents and clinical studies referenced in any such applications and relating solely and specifically to the Product and all annual reports and postmarketing fifteen (15)-day alerts submitted since the most recent such annual report with respect thereto, but in each instance only to the extent: (i) in existence as of the Closing Date; (ii) in the possession of, and controlled and transferable by, Seller or any of Seller’s Affiliates; and (iii) not necessary or appropriate to be retained by Seller in order for Seller to (A) manufacture the Product under the terms of the Supply Agreement or the Schering Supply Agreement or (B) perform obligations following the Closing where performance is expected to be transitioned to Buyer pursuant to the Services Agreement.

“ Regulatory Files ” mean (i) all adverse event reports and other data, information and materials relating to adverse experiences solely and specifically with respect to the Product in the United States and (ii) all material correspondence between Seller or any of Seller’s Affiliates, on the one hand, and any Governmental Entity, on the other hand, relating solely and specifically to the Product in the United States, including any safety reports or updates, complaint files and product quality reviews, but in each instance only to the extent: (x) in existence as of the Closing Date; (y) in the possession or control of Seller or any of Seller’s Affiliates; and (z) not necessary or appropriate to be retained by Seller in order for Seller to (A) manufacture the Product under the terms of the Supply Agreement or the Schering Supply Agreement or (B) perform obligations following the Closing where performance is expected to be transitioned to Buyer pursuant to the Services Agreement.

“ Schering ” means Schering Aktiengesellschaft, a German corporation.

“ Schering License Agreement ” means that certain Collaboration & License Agreement, dated June 9, 1999, by and between Schering and IDEC Pharmaceuticals Corporation, as amended by that certain First Amendment to Collaboration & License Agreement, dated July 13, 2004, by and between Schering and Seller and that certain letter agreement amendment, dated September 16, 2005, by and between Schering and Seller, as the same may be amended from time to time (so long as any such amendment does not provide Schering or any successor or assignee with a right to offer to sell, sell, import or distribute the Product in the United States).

“ Schering Pharmacovigilance Agreement ” means that certain Pharmacovigilance Agreement, dated April 30, 2003, by and between Schering and IDEC Pharmaceuticals Corporation, as the same may be amended from time to time (so long as any such amendment does not provide Schering or any successor or assignee with a right to offer to sell, sell, import or distribute the Product in the United States).

“ Schering Supply Agreement ” means that certain Supply Agreement, dated June 9, 1999, by and between Schering and IDEC Pharmaceuticals Corporation, as amended by that certain letter agreement amendment, dated December 16, 2004, by and between Schering and Seller, as the same may be amended from time to time (so long as any such amendment does not provide Schering or any successor or assignee with a right to offer to sell, sell, import or distribute the Product in the United States).

“ Security Agreement ” means a security agreement to be executed and delivered by Seller and Buyer at the Closing substantially in the form of Exhibit G .

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“ Seller ” has the meaning set forth in the introductory paragraph.

“ Seller Cap Amount ” has the meaning set forth in Section 12.2(b)(ii) .

“ Seller Indemnified Parties ” has the meaning set forth in Section 12.3 .

“ Seller Trade Dress ” means the lay-out, designs and coloring used on the packaging of the Product to the extent used on other product packaging of Seller or any of Seller’s Affiliates.

“ Seller Trademarks ” mean: (i) the “Biogen Idec” name or any variations thereof; (ii) the names “Biogen”, “Idec” and all formatives and derivatives thereof, all composite marks including such names or any such formatives or derivatives and any colorable imitation of any of the foregoing; and (iii) all Trademarks, other than the Product Trademarks, used by Seller or any of Seller’s Affiliates in connection with the manufacture, marketing, sale and distribution of the Product.

“ Services Agreement ” means a services agreement to be executed and delivered by Seller and Buyer at the Closing substantially in the form of Exhibit H .

“ Sublicense Agreements ” mean the sublicense agreements or other arrangements with respect to the Sublicensed Patent Rights under the Sublicensed Patent Rights Agreements to be executed and delivered by Buyer and Seller at the Closing in the forms prepared pursuant to Section 9.4(a) , all of which are intended to “pass-through” the applicable obligations (including economic arrangements) of the Sublicensed Patent Rights Agreements from Seller to Buyer ( i.e. , without any premium or surcharge payable by Buyer to Seller). Sublicense Agreements shall include, as applicable, all amendments or novations of Sublicensed Patent Rights Agreements necessary to achieve such pass-through.

“ Sublicensed Patent Rights ” mean the rights of Seller or any of Seller’s Affiliates to Patents under the Sublicensed Patent Rights Agreements, but solely to the extent that such rights relate solely and specifically to the development, manufacture or sale of the Product in the United States where such Product will only be sold to, or used by, end-users in the United States.

“ Sublicensed Patent Rights Agreements ” mean those certain license agreements to which Seller or any of Seller’s Affiliates is a party listed on Schedule 5.10 .

“ Submission Window ” has the meaning set forth in Section 6.6 .

“ Supply Agreement ” means a supply agreement to be executed and delivered by Seller and Buyer at the Closing substantially in the form of Exhibit I .

“ Tax ” means all domestic and foreign taxes and assessments, including all interest, penalties and additions with respect thereto.

“ Tax Return ” means any report, return, election, notice, estimate, declaration,

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information statement and other forms and documents (including all schedules, exhibits and other attachments thereto) relating to and filed or required to be filed with a taxing authority in connection with any Taxes (including estimated Taxes).

“ Third Party Claim ” has the meaning set forth in Section 12.6(b) .

“ Trademark Assignment ” means the trademark assignment to be executed and delivered by Seller at the Closing substantially in the form of Exhibit J .

“ Trademarks ” mean all United States trademarks, trade names, brand names, logotypes, symbols, service marks, Internet domain names and the goodwill of the business symbolized thereby, including registrations and applications for registrations thereof and all renewals, modifications and extensions thereof.

“ Transaction Documents ” mean this Agreement, the Contract Assignment and Assumption Agreement, the General Assignment and Assumption Agreement, the General Assignment and Bill of Sale, the License Agreement, the License-Back Agreement, the Patent Assignment, the Security Agreement, the Services Agreement, the Supply Agreement, the Sublicense Agreements, the Trademark Assignment and the Transition Services Agreement.

“ Transition Services Agreement ” means a transition services agreement to be executed and delivered by Seller and Buyer at the Closing substantially in the form of Exhibit K .

“ United States ” means the United States of America, together with all of its territories and possessions, and the Commonwealth of Puerto Rico.

“ USPTO ” means the United States Patent and Trademark Office.

“ Yearly Net Sales Amount ” means, with respect to the applicable calendar year, the total amount invoiced by Buyer or any of its direct or indirect Affiliates, assignees, successors, licensees, transferees, distributors or commercial partners (or their respective Affiliates) for sales of the Product or Finished US Goods, or any portion of any of the foregoing, to third parties in bona fide arm’s length transactions less the following deductions, in each case related specifically to the Product or Finished US Goods, or any portion of any of the foregoing, as applicable, and actually taken by such third parties and not otherwise recovered or reimbursed to Buyer or any of its direct or indirect Affiliates, assignees, successors, licensees, transferees, distributors or commercial partners (or their respective Affiliates): (i) the actual cost of such Product or Finished US Goods, or any portion of any of the foregoing, paid to Seller pursuant to the Supply Agreement; (ii) credits or refunds for actual returns of such Product or Finished US Goods, or any portion of any of the foregoing; (iii) Rebates for the purchase of such Product or Finished US Goods, or any portion of any of the foregoing; (iv) sales, use or similar Taxes directly related to the sale of such Product or Finished US Goods, or any portion of any of the foregoing, but only to the extent added to the sales price and separately set forth as such in the total invoiced amount; and (v) freight, packing and handling charges to the extent directly related to the sale of such Product or Finished US Goods, or any portion of any of the foregoing, but only to the extent added to the sales price and separately set forth as such in the total invoiced amount. The gross invoiced amounts referred to in the foregoing sentence exclude amounts

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invoiced among Buyer, its Affiliates and its licensees for quantities of Product or Finished US Goods, or any portion of any of the foregoing, for resale ( i.e. , where the resale is included in the Yearly Net Sales Amount). If any of the Product or Finished US Goods, or any portion of any of the foregoing, is ever sold for compensation other than cash or in a transaction which is not arm’s length, or if Product or Finished US Goods, or any portion of any of the foregoing, would otherwise reach patients or end-users without a sale thereof being included in the calculation of the Yearly Net Sales Amount (other than pursuant to any clinical trial, commercially reasonable sampling program, compassionate use program or the like), then the then-current gross list price of such Product or Finished US Goods, or any applicable portion of any of the foregoing, shall be used in calculating, for the quantities at issue, the Yearly Net Sales Amount.

“ Yearly Royalty Payment ” has the meaning set forth in Section 3.4(a) .

“ Yearly Royalty Payment Expiration Date ” has the meaning set forth in Section 3.4(c) .

Section 1.2 Interpretation .

(a) When used in this Agreement, the words “include,” “includes” and “including” shall be deemed to be followed by the words “without limitation.”

(b) Any terms defined in the singular shall have a comparable meaning when used in the plural, and vice-versa.

(c) All references to any introductory paragraph, recitals, Articles, Sections, Exhibits and Schedules shall be deemed references to the introductory paragraph, recitals, Articles, Sections, Exhibits and Schedules to this Agreement unless otherwise specifically set forth herein.

(d) This Agreement shall be deemed drafted jointly by Buyer and Seller and shall not be specifically construed against either party based on any claim that such party or its counsel drafted this Agreement.

Section 1.3 Currency . All currency amounts referred to in this Agreement are in United States Dollars unless otherwise specified.

ARTICLE II

SALE AND PURCHASE OF PURCHASED ASSETS

Section 2.1 Purchase and Sale . Upon the terms and subject to the conditions of this Agreement, on the Closing Date, Seller shall, and shall cause certain of Seller’s Affiliates to, sell, assign, transfer, convey and deliver to Buyer, and Buyer shall purchase, acquire and accept, all right, title and interest of Seller or any of Seller’s Affiliates in, to and under the Purchased Assets.

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Section 2.2 Purchased Assets .

(a) “ Purchased Assets ” means the following properties, assets and rights of Seller or any of Seller’s Affiliates:

(i) the Assigned Contracts;

(ii) the Books and Records;

(iii) the Post-BLA Clinical Trial Records;

(iv) the Product Domain Names;

(v) the Product Marketing Materials;

(vi) the Product Patents;

(vii) the Product Toll-Free Number;

(viii) the Product Trade Dress;

(ix) the Product Trademarks;

(x) the Regulatory Applications/Approvals;

(xi) the Regulatory Files; and

(xii) all unfilled Customer Orders as of the Closing Date ( i.e. , Customer Orders to the extent that (A) the Finished US Goods at issue have not been shipped to the applicable customer as of the Closing Date and (B) Buyer (rather than Seller or any of its Affiliates) would be paid by the applicable customer after shipment by Buyer following the Closing Date), a list of which shall be provided to Buyer within ten (10) Business Days after the Closing Date.

(b) Notwithstanding the foregoing, or any other provision herein to the contrary, Buyer and Seller expressly agree and acknowledge that the Purchased Assets shall not include any of the following (collectively, the “ Excluded Assets ”):

(i) any tangible property (except as expressly included in the Purchased Assets above);

(ii) the Schering License Agreement, the Schering Pharmacovigilance Agreement and the Schering Supply Agreement;

(iii) the right to sue under any of the Purchased Assets for events or circumstances occurring prior to the Closing Date;

(iv) the Excluded Intellectual Property; and

(v) all properties, assets and rights of Seller or any of Seller’s Affiliates other than the Purchased Assets.

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(c) Buyer acknowledges and agrees that Seller and any of Seller’s Affiliates may retain (and be entitled to use the information in) copies of any or all parts of the documentation that Seller or any of Seller’s Affiliates deliver to Buyer hereunder or that otherwise constitute Purchased Assets: (i) for archival purposes; (ii) to fulfill or otherwise dispose of any of the Pre-Closing Liabilities; (iii) to fulfill or otherwise dispose of any of Seller’s or any of Seller’s Affiliates rights or obligations under the Security Agreement, the Services Agreement, the Supply Agreement or the Transition Services Agreement; (iv) for use in connection with any pending or threatened Action; (v) to fulfill or otherwise dispose of any of Seller’s or any of Seller’s Affiliates obligations under the Schering License Agreement, the Schering Pharmacovigilance Agreement or the Schering Supply Agreement; or (vi) for such other purposes as Seller may reasonably request, subject to Buyer’s prior written consent (which consent shall not be unreasonably withheld, conditioned or delayed).

Section 2.3 Pre-Closing and Post-Closing Liabilities . Except (i) as otherwise provided in the Supply Agreement and (ii) for such allocations of liability between the parties as are expressly set forth in the Services Agreement and the Transition Services Agreement:

(a) Buyer, and not Seller or any of its Affiliates, shall be liable, as between Seller and its Affiliates on the one hand and Buyer and its Affiliates on the other hand, for any and all Liabilities and Actions to the extent arising in connection with the Commercialization, the Purchased Assets or any acts or omissions of Buyer or any of its direct or indirect Affiliates, assignees, successors, licensees, transferees, distributors or commercial partners (or their respective Affiliates) related thereto from and after the Closing Date, including Assumed Contractual Obligations (collectively, the “ Post-Closing Liabilities ,” as further illustrated by subsections (c)  and (d)  below); provided , however , that Post-Closing Liabilities shall specifically not include any manufacturing or purchase orders for materials delivered to or on behalf of Seller prior to the Closing Date or any rebates to be paid on Product sales made prior to the Closing Date;

(b) Seller, and not Buyer or any of its Affiliates, shall be liable, as between Buyer and its Affiliates on the one hand and Seller and its Affiliates on the other hand, for any and all Liabilities and Actions to the extent arising in connection with the Commercialization, the Purchased Assets or any acts or omissions of Seller or any of its direct or indirect Affiliates, assignees, successors, licensees, transferees, distributors or commercial partners (or their respective Affiliates) related thereto prior to the Closing Date (collectively, the “ Pre-Closing Liabilities ,” as further illustrated by subsections (c)  and (d)  below), and Buyer will not assume or be responsible for any Pre-Closing Liabilities; provided , however , that any manufacturing or purchase orders for materials delivered to or on behalf of Seller prior to the Closing Date and any rebates to be paid on Product sales made prior to the Closing Date shall also be specifically included in Pre-Closing Liabilities; and

(c) For the avoidance of doubt, by way of example, the Post-Closing Liabilities shall include any Liabilities and Actions to the extent arising in connection with any quantities of Product sold (or in the alternative, if Product at issue was not sold, then

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administered to or taken by a patient) in the United States after the Closing Date, and the Pre-Closing Liabilities shall include any Liabilities and Actions to the extent arising in connection with any quantities of Product sold (or in the alternative, if Product at issue was not sold, then administered to or taken by a patient) prior to the Closing Date. It is hereby acknowledged that an Action initiated by a patient taking Product in the United States both before and after the Closing may involve both Pre-Closing Liabilities and Post-Closing Liabilities, in which event the parties shall cooperate with one another to determine and implement an appropriate strategy for defending against any related Actions.

(d) For the avoidance of doubt, by way of example, the Post-Closing Liabilities (and the Assumed Contractual Obligations) shall include (and the Pre-Closing Liabilities shall exclude) any payment obligation that first becomes due and payable under an Assigned Contract after the Closing Date, even to the extent that such payment obligation may relate to activities under such Assigned Contract that are substantially performed before the Closing Date.

ARTICLE III

PURCHASE PRICE

Section 3.1 Purchase Price . The purchase price for the Purchased Assets shall be Ten Million Dollars ($10,000,000) in cash (the “ Purchase Price ”), which shall be payable at the Closing in accordance with Section 4.2(b) .

Section 3.2 Allocation of Purchase Price . The Purchase Price shall be allocated among the Purchased Assets as of the Closing Date in accordance with any Governmental Rule and as otherwise agreed upon in writing by the parties. Buyer and Seller each agree to (i) report (and to cause its respective Affiliates to report) the transactions contemplated by this Agreement in a manner consistent with any Governmental Rule and with the terms of this Agreement (including the allocation agreed upon in writing by the parties) and (ii) not to take any position inconsistent therewith in any Tax Return, in any Tax refund claim, in any litigation or otherwise.

Section 3.3 Milestone Payments . In addition to the Purchase Price and the Yearly Royalty Payments, within thirty (30) days after each of the Milestone Events Buyer shall pay to Seller the corresponding Milestone Payment by wire transfer in immediately available funds to an account or accounts designated in writing by Seller. The Milestone Events and the corresponding Milestone Payments are as follows:

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Buyer acknowledges and agrees that more than one of the Milestone Events could occur in any calendar year and that such an occurrence would not reduce any of the applicable Milestone Payments.

Section 3.4 Yearly Royalty Payments .

(a) In addition to the Purchase Price and the Milestone Payments, on or before March 1 of each calendar year starting with March 1, 2008 and continuing until March 1 of the calendar year following the Yearly Royalty Payment Expiration Date, Buyer shall pay to Seller the Yearly Royalty Payment for the preceding calendar year by wire transfer in immediately available funds to an account or accounts designated in writing by Seller. The “ Yearly Royalty Payment ” shall be equal to a percentage of the Yearly Net Sales Amount for the preceding calendar year as follows (noting, for this purpose, that the Yearly Royalty Payment will be the sum of the two separate amounts if and when more than one percentage calculation applies in calendar years 2007 through 2013):

(b) Assuming a Closing, then on or before March 1 of each calendar year starting with March 1, 2008 and continuing until March 1 of the calendar year following the Yearly Royalty Payment Expiration Date, Buyer shall deliver to Seller a written report, certified as accurate by an officer of Buyer, stating the Yearly Net Sales Amount for the preceding calendar year (but only for that period following the Closing Date in the instance of 2007) and the Yearly Royalty Payment for the preceding calendar year. In no event shall the receipt or acceptance by Seller of such report or a Yearly Royalty Payment prevent Seller from subsequently challenging the validity or accuracy of such report or a Yearly Royalty Payment. Buyer shall keep, and require its direct or indirect Affiliates, assignees, successors, licensees, transferees, distributors or commercial partners (or their respective Affiliates) to keep, full, complete and proper records and accounts of all sales of the Product or Finished US Goods, or any portion of any of the foregoing, in sufficient detail to enable the Yearly Royalty Payment to

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be determined. Seller shall have the right to appoint an independent certified public accounting firm approved by Buyer (which approval shall not be unreasonably withheld, conditioned or delayed) to audit the records of Buyer or any of its direct or indirect Affiliates, assignees, successors, licensees, transferees, distributors or commercial partners (or their respective Affiliates) as necessary to verify a Yearly Royalty Payment. Buyer shall pay to Seller an amount equal to any additional portion of a Yearly Royalty Payment to which Seller is entitled as disclosed by such audit plus a late charge thereon at the rate of one and one-half percent (1.5%) per month. Such audit shall be at Seller’s expense; provided , however , that if such audit discloses that Seller was underpaid a Yearly Royalty Payment by at least five percent (5%), then Buyer shall reimburse Seller for the reasonable costs of such audit. Seller may exercise its right to audit as to each of Buyer or any of its direct or indirect Affiliates, assignees, successors, licensees, transferees, distributors or commercial partners (or their respective Affiliates) no more frequently than once in any calendar year or more than once in respect of any calendar year, and the accounting firm performing such audit shall execute a confidentiality agreement enforceable by Buyer that prohibits the accounting firm from divulging information obtained in connection with the audit (other than the disclosure to Seller of information relating to the accuracy of the Yearly Royalty Payment). Any such audit shall be permitted during business hours within fifteen (15) days of Buyer’s receipt of Seller’s notice to proceed with an audit. Buyer shall preserve and maintain, and cause its direct or indirect Affiliates, assignees, successors, licensees, transferees, distributors or commercial partners (or their respective Affiliates) to preserve and maintain, all books and records required for such an audit for a period of at least five (5) years after the calendar year to which the books and records apply.

(c) For the calendar year in which the Yearly Royalty Payment Expiration Date occurs, the Yearly Net Sales Amount shall only be calculated for that portion of such calendar year prior to the Yearly Royalty Payment Expiration Date. The “ Yearly Royalty Payment Expiration Date ” means the latest of: (i) the expiration date of the last to expire of any of the Product Patents, the Licensed Patents or the Patents for which a sublicense has been granted to Buyer under the Sublicense Agreements; (ii) the day on which a third Person begins to lawfully sell a Biosimilar Product in the United States of America; or (iii) December 31, 2015.

Section 3.5 Transfer Taxes . All transfer, sales, value added, stamp duty and similar Taxes payable in connection with the transactions contemplated hereby, to the extent payable to any Governmental Entity, shall be borne by Buyer. Notwithstanding the foregoing, Buyer and Seller shall each be obligated for any Taxes to the extent payable or assessed based upon the income or worth of such party.

ARTICLE IV

THE CLOSING

Section 4.1 Closing Date . The closing of the sale and transfer of the Purchased Assets (the “ Closing ”) shall take place at Seller’s offices at 5200 Research Place, San Diego, California 92122, on the first Business Day following the date on which all of the conditions to each party’s obligations under Article X have been satisfied or waived, or at such other date or place as may be mutually agreed to by Buyer and Seller (such date of the Closing being the “ Closing Date ”).

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Section 4.2 Closing Activities .

(a) At the Closing, (i) Seller shall deliver or cause to be delivered to Buyer each of the items referred to in Section 10.2(a) , (b)  and (d) , in each case appropriately executed, and (ii) Buyer shall deliver or cause to be delivered to Seller each of the items referred to in Section 10.3(a) , (b)  and (c) , in each case appropriately executed.

(b) At the Closing, Buyer shall deliver or cause to be delivered to Seller payment of the Purchase Price by wire transfer in immediately available funds to an account or accounts designated in writing by Seller.

ARTICLE V

REPRESENTATIONS AND WARRANTIES OF SELLER

Seller hereby represents and warrants to Buyer, except as set forth on the Disclosure Schedule, as follows:

Section 5.1 Organization; Good Standing . Seller is a corporation duly organized, validly existing and in good standing under the laws of the State of Delaware. Each of Seller and Seller’s Affiliates has the requisite power and authority to own the Purchased Assets, as the case may be, and to carry on its business with respect to the Product as currently conducted. Each of Seller and Seller’s Affiliates is duly qualified to conduct business as a foreign corporation and is in good standing in each jurisdiction where the nature of the business conducted by it makes such qualification necessary, except where the failure to so qualify or be in good standing would not have a Material Adverse Effect.

Section 5.2 Authority; Execution and Delivery . Seller has the requisite power and authority to enter into this Agreement and to consummate the transactions contemplated hereby. The execution and delivery of this Agreement by Seller and the consummation of the transactions contemplated hereby have been duly and validly authorized by Seller and, as applicable, Seller’s Affiliates. This Agreement has been duly executed and delivered by Seller and, assuming the due authorization, execution and delivery of this Agreement by Buyer, will constitute the legal, valid and binding obligation of Seller, enforceable against it in accordance with its terms, subject to applicable bankruptcy, insolvency, reorganization, moratorium, fraudulent transfer and other similar laws affecting creditors’ rights generally from time to time in effect and to general principles of equity regardless of whether considered in a proceeding in equity or at law.

Section 5.3 No Violation; Consents . The execution and delivery of this Agreement or any of the Transaction Documents by Seller and, as applicable, Seller’s Affiliates do not, and the consummation of the transactions contemplated hereby or thereby and compliance with the terms hereof or thereof by Seller and such Seller’s Affiliates will not: (i) violate any Governmental Rule to which Seller and such Seller’s Affiliates are subject; (ii) breach or violate any provision of the Certif