LIST OF EXHIBITS

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This ASSET PURCHASE AGREEMENT (this “ Agreement ”), dated as of January 15, 2007 (the “ Effective Date ”), between VALENTIS, INC., a Delaware corporation, (acting on behalf of itself and as agent for its Affiliates) (“ Valentis ” or “Seller”), and MEDAREX, Inc. a New Jersey corporation (“Medarex” or “Buyer”).

WHEREAS, Valentis desires to sell the Acquired Assets, on the terms and conditions set forth in this Agreement; and

WHEREAS, Medarex wishes to purchase, on the terms and conditions set forth in this Agreement, the Acquired Assets excluding all Liabilities, past, present or future related to the Acquired Assets.

NOW, THEREFORE, in consideration of the foregoing recitals and the mutual covenants and agreements of the Parties contained in this Agreement, intending to be legally bound, the Parties hereby agree as follows:

ARTICLE I.

SALE AND PURCHASE OF ASSETS

Section 1.01  Purchase; and Sale        On January 15, 2007 or such date as the Parties agree to in writing (“Closing Date”). Valentis shall, and shall cause its Affiliates, on the terms and subject to the conditions of this Agreement, to sell, assign, transfer, convey and deliver to Medarex, free and clear of all encumbrances, and Medarex shall purchase from Valentis and its Affiliates, all of the right, title and interest in, to and under the Acquired Assets, for a fully paid fee of: Two Hundred and Fifty Thousand Dollars ($250,000) U.S. (“Purchase Price”).  The purchase and sale of the Acquired Assets are referred to in this Agreement collectively as the “Acquisition”.

Section 1.02 Transfer of Assets  

(a)            Medarex desires to purchase and Valentis desires to sell, transfer, assign, bargain, convey and deliver all right, title and interest to Medarex of certain intellectual property (including all Patents, patent applications and trade secrets)  contracts and license agreements, know-how, data, information and materials relating to the developmental endothelial locus-1 (“Del-1”) gene, Del-1 protein, and certain Del-1 antibodies (collectively “Del-1 MAb Program”) that are owned, in-licensed or otherwise controlled by Valentis solely as expressly set forth in this Agreement and as contained in the Exhibits to this Agreement (listed below) (collectively, the “Acquired Assets”):

(i)             the intellectual property (including the Patents) set forth in Exhibit A and any divisions, continuations, continuations-in-part, reexaminations, reissues, substitutions, renewals, restorations, additions or registrations thereof, as well as any non-U.S. counterparts thereof and extensions and supplementary protection certificates based thereon;

(ii)            Materials described in Exhibit C

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(iii)           the license agreements set forth in Exhibit B (the “Contracts”);

(iv)           all the rights owned or controlled by Valentis related exclusively to the Acquired Assets; and

(v)            all information, materials, files, documents, instruments, papers, books and records (scientific or financial) of Valentis to the extent related to the Acquired Assets.

(b)            Delivery of Acquired Assets.  Valentis shall promptly execute and deliver to Medarex any and all assignments, endorsements and other documents necessary to effectuate the terms and conditions of this Agreement.  On the Closing Date, Valentis shall make available to Medarex possession of the Acquired Assets, provided however that the expense of retrieving, removing and transferring the Acquired Assets shall be born exclusively by Valentis.  Valentis’ assignment of the Contracts to Medarex expressly includes all rights therein, including without limitation, any right to receive or obligation to make payment for products licensed and services rendered after the Closing Date of this Agreement, and, after the Closing Date, to receive goods and services and to assert claims and to take other actions with respect to breaches and defaults thereunder (“Assigned Contracts”), provided, that this Agreement shall not constitute an assignment or attempted assignment or agreement to assign an Assigned Contract if an assignment or attempted assignment of an Assigned Contract without the consent of the other party or parties thereto would constitute a breach of the Assigned Contract.  If, after the Closing Date, there exist any uncompleted or ineffective Assigned Contracts to Medarex, Valentis, at its sole cost, will obtain, and Medarex will cooperate with Valentis to obtain, within thirty (30) business days after the Closing Date, any consents required for the assignment of any Assigned Contract to Medarex or any novations of the Assigned Contract to make Medarex a party directly (“Time to Obtain Consents”).  Medarex shall promptly provide notice to Valentis of any and all consents, novations or assignments that it has not received during the Time to Obtain Consents and Valentis shall promptly cooperate with Medarex to obtain any and all consents, novations or assignments not received.  If such consent or novation is not obtained within the Time to Obtain Consents or if an attempted assignment would be ineffective or impair Medarex’s rights under the applicable Assigned Contract, the parties may, in Medarex’s sole option (i) cooperate to insure that the benefits of the Assigned Contract will inure to Medarex (including the remittance by Valentis to Medarex of any revenues paid to Valentis which would be Medarex’s revenue if the Assigned Contracts have been assigned); and (2) cooperate to insure that Valentis performs and discharges all of Medarex’s obligations under the Assigned Contracts as a subcontractor or otherwise (“Workaround Due to Ineffective Assignment”).  If Medarex decides to opt against pursuing the Workaround Due to Ineffective Assignment and Medarex has provided timely notice to Valentis of any and all consents or assignments not received by Medarex during the Time to Obtain Consents, then this Agreement shall automatically become null and void,  Valentis shall immediately return to Medarex the Purchase Price in full, and each Party shall be relieved of any and all obligations to the other Party that are set forth in this Agreement, financial or otherwise, except the Survival of Covenants obligations.

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(c)            Medarex acknowledges and agrees that it is not acquiring any rights, title or interest in, to or under, and the Acquired Assets shall not include, any of the following asset(s) (the “ Excluded Assets ”):

(i)             any and all cash and cash equivalents of Valentis or any of its Affiliates;

(ii)            any and all other manufacturing equipment and packaging assets owned or leased by Valentis or any of its Affiliates that relate to the Acquired Assets;

(iii)           any and all Valentis Names and any and all logos, variations or derivatives thereof except for the tradenames expressly included in Exhibit A as part of the Acquired Assets;

(iv)           any and all refunds or credits of Taxes not attributable to the Acquired Assets;

(v)            any and all Retained Information, except as expressly provided in Section 1.02 (b);

(vi)           any and all other intellectual property or intellectual property rights that (a) do not pertain to the Acquired Assets; and (2) are not part of the List of Patents in Exhibit A (collectively, “Excluded IP”);and

(vii)          any and all rights, claims and credits of Valentis or any of its Affiliates arising under insurance policies and all guarantees, warranties, indemnities and similar rights in favor of Valentis or any of its Affiliates relating to any Excluded Asset.

(d)            Medarex shall acquire the Acquired Assets free and clear of all Liens and Liabilities.

Section 1.03 No Assumed Liabilities, Medarex Assumed Obligations and Excluded Liabilities   

(a)            Medarex agrees, effective as of the Closing Date, to assume those liabilities of Valentis expressly listed in this Section 1.03 (a) (collectively, the “Assumed Liabilities” and as defined in Section 7.02 of this Agreement):  No assumed Liabilities.

(i) Medarex shall assume, effective as of the Closing Date, and from and after the Closing Date, only those contracts, agreements, covenants and/or obligations that pertain to the Acquired Assets and that are listed in the Exhibits to this Agreement (“Medarex Assumed Obligations”). The foregoing shall not in anyway limit or be construed to limit Medarex’s indemnity obligations as set forth in Section 4.02(c)

(b)            Except as expressly set forth in Section 1.03 (a) above, Medarex shall not assume or become obligated in any way to pay any Liabilities, debts or obligations of Valentis whatsoever, including but not limited to any liabilities or obligations, including taxes and other

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charges, now or hereafter arising from Valentis’ business activities that took place prior to the Closing Date.  All Liabilities, debts and obligations of Valentis not expressly assumed by Medarex under this Agreement are “Excluded Liabilities”; Excluded Liabilities include, but are not limited to:

                    (i)   any Liens and encumbrances to which the Acquired Assets are subject, or would have been subject to,  prior to and/or on the Closing Date;

                     (ii)    any liability or obligation relating to Taxes of Valentis, including any interest or penalties related thereto;

                    (iv)    any warranty or performance liability claims relating to the Acquired Assets which arose prior to and/or on the Closing Date; and

                    (v)  any liability or obligation of the Valentis, absolute or contingent, known or unknown not expressly agreed to be assumed by Medarex pursuant to this Agreement.

Section 1.04  Closing; Closing Deliveries

(a)          The consummation of the transactions contemplated by this Agreement (the “ Closing ”) will take place on the Closing Date.

(b)            On the Closing Date, Valentis shall deliver or cause to be delivered to Medarex the following:

(i)             The Acquired Assets in such mutually agreeable format as reasonably requested; and

(ii)            Copies of all files and records relating to the Acquired Assets.

(c)            On the Closing Date, Medarex, subject to the terms and conditions of this Agreement, shall deliver to Valentis the following:

(i)             The full and complete Purchase Price, payable to Valentis by wire transfer of immediately available funds to a bank account designated in writing by Valentis.

(d)            If the Closing does not occur on the Closing Date, or such later date upon which Medarex and Valentis may agree to in writing, this Agreement shall terminate upon written notice of termination given by either Party that is not in default of its obligations hereunder, and thereupon this Agreement shall become null and void and no Party will have any further rights or obligations under this Agreement, except with respect to the Survival of Covenants obligations.

ARTICLE II.

REPRESENTATIONS AND WARRANTIES OF VALENTIS

Valentis represents and warrants to Medarex as follows:

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Section 2.01      Organization Valentis is duly organized, validly existing and in good standing under the laws of the State of Delaware.

Section 2.02  Authority; Execution and Delivery; Enforceability Valentis has the requisite corporate power and authority to execute and deliver this Agreement and to perform all of its obligations hereunder.  The execution and delivery of this Agreement and the performance by Valentis of its obligations hereunder have been authorized by all requisite corporate action on its part.  This Agreement has been validly executed and delivered by Valentis.  Assuming that this Agreement has been duly authorized, executed and delivered by Medarex, this Agreement constitutes a valid and binding obligation of Valentis, enforceable against Valentis in accordance with its terms, except as such enforceability may be limited by (a) bankruptcy, insolvency, moratorium, reorganization or other laws of general applicability relating to or affecting the enforcement of creditors’ rights generally and general principles of equity; and (b) laws limiting the availability of specific performance, injunctive relief or other equitable remedies. None of the following:  the execution and delivery of this Agreement by Valentis, the performance by Valentis of its obligations under this Agreement or the consummation of the Acquisition, knowingly:

(i)             violates the certificate of incorporation, by-laws or other organizational documents of Valentis;

(ii)            conflicts in any respect with or results in a violation or breach of, or constitutes a default under, any contract, agreement or instrument to which Valentis is a party or by which Valentis or any Acquired Asset is bound, or results in the creation or imposition of any Lien upon any Acquired Asset;

(iii)           conflicts or violates with any existing law (including common law), statute, rule, regulation, ordinance, judgment, order or decree (each, a “ Law ”) applicable to Valentis or the Acquired Assets; or

(iv)           materially impairs Valentis’ ability to consummate the transactions contemplated hereby or materially delays the consummation of the transactions contemplated hereby.

(b)            No filing with, and no permit, authorization, consent or approval of any Governmental Entity is necessary for the consummation by Valentis of the transactions contemplated by this Agreement.

Section 2.03      Title to Assets (a)      As of the Effective Date of this Agreement, and subject to the rights held by Vanderbilt University to certain Patents that Medarex acknowledges were fully disclosed to Medarex heretofore as addressed in a letter from Valentis to Vanderbilt, containing a signed acknowledgement from Vanderbilt, attached as Exhibit E to this Agreement, Valentis and/or its Affiliates have good and valid title to all of the Acquired Assets, in each case, free and clear of all Liens and Valentis and/or its Affiliates are the sole legal and beneficial owner of the Acquired Assets and have the right to sell them to Medarex in accordance with this Agreement.

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(b)            Valentis and/or its Affiliates have the sole and exclusive right to enforce, license or transfer, without payment to any Third Party, each item of the Acquired Assets.

Section 2.04      Intellectual Property Rights

(a)          Except as set forth herein, neither Valentis nor any of its Affiliates has granted any option, license or right to use any of the Acquired Assets.

(b)         Valentis has no knowledge of any claim made against Valentis or brought by any Third Party arising from the Acquired Assets as of the Effective Date of this Agreement.

Section 2.05      Material Facts Neither this Agreement nor any written statement or certificate furnished in connection herewith or any of the transactions contemplated hereby, contains an untrue statement of a material fact or omits to state a material fact that is necessary in order to make the statements contained herein and therein, in the light of the circumstances under which they are made, not misleading.  There are no facts that affect, or in the future might reasonably be expected to affect, adversely the Acquired Assets in any material respect that is not set forth in this Agreement.

Section 2.06      No Proceedings There are no proceedings pending or, to the Knowledge of Valentis, threatened against Valentis which would reasonably be expected to affect Valentis’ ability to consummate the transactions contemplated by this Agreement.

Section 2.07      Brokers or Finders Neither Valentis nor its Affiliates have retained any agent, broker, investment banker, financial advisor or other firm or person that is or will be entitled to any brokers’ or finder’s fee or any other commission or similar fee in connection with any of the transactions contemplated by this Agreement, and there are no claims for any of the foregoing.

Section 2.08      Disclaimer

Except as expressly set forth in this Agreement, the Acquired Assets assigned by Valentis pursuant to this Agreement are provided “AS IS” without any warranty, express, implied or statutory and Valentis expressly disclaims any warranty of non-infringement, fitness for a particular purpose or merchantability with respect to any Acquired Asset assigned or delivered pursuant to this Agreement.  This Disclaimer is an essential part of the bargain between Valentis and Medarex.

ARTICLE III.

REPRESENTATIONS AND WARRANTIES OF MEDAREX

Medarex represents and warrants to Valentis as follows:

Section 3.01      Organization Medarex is duly organized, validly existing and in good standing under the laws of the State of New Jersey.  Medarex has all requisite corporate power

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and authority to execute and deliver this Agreement and to perform all of its obligations hereunder.

Section 3.02      Authority; Execution and Delivery; Enforceability   The execution and delivery of this Agreement and the performance by Medarex of its obligations hereunder have been authorized by all requisite corporate action on the part of Medarex.  This Agreement has been validly executed and delivered by Medarex.  Assuming that this Agreement has been duly authorized, executed and delivered by Valentis, this Agreement constitutes a valid and binding obligation of Medarex, enforceable against Medarex in accordance with its terms, except as such enforceability may be limited by (a) bankruptcy, insolvency, moratorium, reorganization or other laws of general applicability relating to or affecting the enforcement of creditors’ rights generally and general principles of equity; and (b) law limiting the availability of specific performance, injunctive relief or other equitable remedies.

(a)            None of the following: execution and delivery of this Agreement by Medarex, the performance by Medarex of its obligations under this Agreement or the consummation of the Acquisition:

(i)             violates the certificate of incorporation, by-laws or other organizational documents of Medarex ;

(ii)            conflicts in any respect with or results in a violation or breach of, or constitutes a default under, any material contract, agreement or instrument to which Medarex is a party or by which Medarex is bound;

(iii)           conflicts or violates with any existing Law applicable to Medarex;  or

(iv)           materially impairs Medarex’s ability to consummate the transactions contemplated hereby or materially delays the consummation of the transactions contemplated hereby.

(b)            No filing with, and no permit, authorization, consent or approval of, any Governmental Entity is necessary for the consummation by Medarex of the transactions contemplated by this Agreement.

Section 3.03      Brokers or Finders Neither Medarex nor its Affiliates have retained any agent, broker, investment banker, financial advisor or other firm or person that is or will be entitled to any brokers’ or finder’s fee or any other commission or similar fee in connection with any of the transactions contemplated by this Agreement, and there are no claims for any of the foregoing.

Section 3.04      No Proceedings There is no proceedings pending or, to the knowledge of Medarex, threatened against Medarex which would reasonably be expected to affect Medarex’s ability to consummate the transactions contemplated by this Agreement.

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ARTICLE IV.

COVENANTS

Section 4                 Conditions to Closing

(a)            Conditions to Medarex’s Obligations .  The obligations of Medarex under this Agreement shall be subject to the satisfaction and fulfillment of each of the following conditions, except as Medarex may expressly waive the same in writing:

(i)             Accuracy of Representations and Warranties on Closing Date.   The representations and warranties made herein by Valentis shall be true and correct in all material respects, and not misleading in any material respect, on and as of the date given, and on and as of the Closing Date with the same force and effect as though such representations and warranties were made on and as of the Closing Date.

(ii)            Compliance .  As of the Closing Date, Valentis shall have compiled in all material respects with, and shall have fully performed, in all material respects, all conditions, covenants and obligations imposed on Valentis and required to be performed or complied with by Valentis at, or prior to, the Closing Date.

(iii)           Delivery of the Acquired Assets .  Valentis shall have made the Acquired Assets available to Medarex as set forth in this Agreement.

(iv)           Delivery of Closing Documents .   Valentis shall have delivered, and Medarex shall have received, the documents described in this Agreement, including the Exhibits.

(b)            Conditions to Valentis’ Obligations     The obligations of Valentis hereunder shall be subject to the satisfaction and fulfillment of each of