EXHIBIT 10.39

LEASE TERMINATION AGREEMENT

THIS LEASE TERMINATION AGREEMENT(this "Agreement") is entered into as of the Reference
Date by and between Landlord and Tenant, with reference to the following:

1.     General Terms.

| |  | (a) |  | Reference Date:   |  | September 4, 2003                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
| |  | --- |  | ----------------- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| |  | (b) |  | Landlord:         |  | WOODLANDS OFFICE EQUITIES-'95 LIMITED
a Texas limited partnership                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
| |  | (c) |  | Tenant:           |  | VALENTIS, INC.,
a Delaware corporation                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
| |  | (d) |  | Building:         |  | Valentis Building, 8301 New Trails, The Woodlands,
Montgomery County, Texas                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
| |  | (e) |  | Lease:            |  | Lease Agreement between Landlord and Tenant dated October 29, 1993, as amended and modified                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
| |  | (f) |  | Premises:         |  | 4.2 acres described on Exhibit A attached hereto with the 38,400 rentable square foot Building and other improvements located thereon.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
| |  | (g) |  | Termination Date: |  | 11:59 p.m. on September 4, 2003                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
| |  | (h) |  | Termination Fee:  |  | (i) $232,000.00 payable by Tenant on or before the Termination Date, $151,330.34 of which shall be paid to Landlord from proceeds held by DoveBid from the sale of equipment formerly located at the Premises and on which Landlord has a valid and
perfected security interest, and the balance of which being paid in good funds directly from Tenant to Landlord, and (ii) 185,000 shares of common stock of Tenant, par value $.001 per share, together with certain rights set forth in the
agreement, attached hereto as Exhibit B (the "Stock Issuance and Restriction Agreement"), pertaining to Landlord's registration rights for, and Tenant's option to repurchase, those
shares.

2.     Recitals.

(a)   Pursuant
to the Lease, Landlord, as successor in-interest to The Woodlands Corporation, leased to GeneMedicine, Inc. and GeneMedicine, Inc.
leased from Landlord, the Premises located in the Building upon the terms and at the rental more particularly set forth in the Lease.

(b)   Tenant,
formerly known as Megabios Corp., is the successor in interest to GeneMedicine, Inc. under the Lease.

(c)   Tenant
desires to terminate the Lease, and Landlord is willing to agree to a termination of the Lease subject to the terms and conditions set forth in this Agreement and
the Stock Issuance and Restriction Agreement. Capitalized terms used in this Agreement, unless expressly provided otherwise in this Agreement, shall have the same meanings given to such terms in the
Lease.

3.Termination.    For good and valuable consideration, the receipt and adequacy
of which are acknowledged, the Lease is terminated as of the Termination Date subject to the conditions set forth in this Agreement and the Stock Issuance and Restriction Agreement. Thereafter, Tenant
shall have no further right to occupy and/or use the Premises. After the Termination Date and Tenant's payment of the Termination Fee, neither Tenant nor Landlord shall have any further liability or
obligation to the

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other
with respect to the Lease, except as expressly set forth in this Agreement and the Stock Issuance and Restriction Agreement.

4.Tenant's Obligations.    By the Termination Date, Tenant shall have
(a) peaceably vacated and surrendered the Premises to Landlord; (b) paid to Landlord the Termination Fee; (c) removed from the Premises all persons occupying and using the
Premises by, through or under Tenant and removed from the Premises all personal property (other than fixtures) owned by Tenant; and (d) returned to Landlord all suite keys, restroom keys and
security cards issued to Tenant in connection with its use of the Premises, all of the foregoing being subject to the satisfaction of Landlord.

5.Mutual Release.    Effective on the Termination Date:

(a)   Tenant,
on behalf of itself and its partners, officers, directors, agents, employees, successors in interest and assigns, releases and discharges Landlord, its
affiliates, subsidiaries and designated property management construction and marketing firms, and their respective partners, members, officers, directors, agents, employees, contractors, successors in
interest and assigns, from and against any and all claims, demands, causes of action, liabilities and obligations, known and unknown, foreseen and unforeseen, direct and indirect, in any way arising
out of or relating to the Lease and/or Tenant's use and occupancy of the Premises; it being the express intention of the parties that the foregoing shall be deemed to be a full and general release,
except for the provisions of this Agreement and the Stock Issuance and Restriction Agreement.

(b)   Landlord,
on behalf of itself and its affiliated companies, partners, officers, directors, agents, employees, successors in interest and assigns, releases and discharges
Tenant and Tenant's partners, officers, directors, agents, employees, successors in interest and assigns from and against any and all claims, demands, causes of action, liabilities and obligations,
known and unknown, foreseen and unforeseen, direct and indirect, in any way arising out of or relating to the Lease and/or Tenant's use and occupancy of the Premises; it being the express intention of
the parties that the foregoing shall be deemed to be a full and general release, except for the following items which shall survive the termination of the Lease: (i) Tenant's obligations under
the Lease which accrue prior to the Termination Date other than the obligation to pay Base Rent or Additional Rent; (ii) Tenant's obligations under the Lease which pertain to the vacation or
condition of the Premises, insurance, indemnification and any other provisions which expressly survive the termination of the Lease other than the obligation to pay Base Rent or Additional Rent; and
(iii) the provisions of this Agreement and the Stock Issuance and Restriction Agreement.

6.Access.    Landlord may prohibit access by Tenant to the Premises after the
Termination Date by changing the locks to the Premises or by any other means permitted by the Lease, at law or in equity.

7.     Removal of Property.

(a)   Notwithstanding
anything in the Lease to the contrary, all permanent or built-in fixtures or improvements, all mechanical, electrical and plumbing equipment,
all furnishings, equipment, furniture, trade fixtures and other equipment in the Premises shall be and become the property of Landlord as of the Termination Date.

(b)   If
any furnishings, equipment, furniture, trade fixtures or other equipment are located on the Premises on the Termination Date, Tenant grants to Landlord the option,
exercisable at any time thereafter without the requirement of any notice to Tenant, (i) to treat such property, or any part of such property, as being abandoned by Tenant to Landlord, in which
event Landlord shall be deemed to have full rights of ownership in such abandoned property; provided however, that Landlord shall not assume title to, or an ownership interest in, and Tenant shall be
liable for the cleanup and removal of, any "solid waste," or other material which is regulated as hazardous by any applicable environmental, health or safety laws which by, through, or under Tenant
was caused to be located on the Premises, and

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any
such material shall be disposed of as required by such laws at Tenant's sole cost and expense; or (ii) to sell, give away, donate or dispose of as trash or refuse any or all of such
property without any responsibility to deliver to Tenant any proceeds from such disposition. Landlord shall have no liability of any kind whatsoever to Tenant in respect of the exercise or failure to
exercise the options set forth in thisParagraph 7. Specifically, Tenant shall not have the right to assert against Landlord a claim either for
the value, or the use, of any such property, either as an offset against any amount of money owing to Landlord or otherwise. The provisions of this Paragraph 7shall supersede the applicable
provisions of the Texas Property Code, specifically including without limitation Section 93.002(d)and(e)thereof, as amended from time to time, and
any other law purporting to
restrict the options granted to Landlord in thisParagraph 7.

8.Attorneys' Fees.    In the event of any action to enforce this Agreement, the
prevailing party shall be entitled to receive from the other party all costs and expenses, including all attorneys' fees and costs of court (or other venue of dispute resolution), incurred in
connection with such action.

9.Successors and Assigns; Time.    This Agreement shall be binding upon and
inure to the benefit of Landlord and Tenant and their respective predecessors, successors and assigns. Time is of the essence with respect to all provisions of this Agreement.

10.   Authority; Joint and Several Liability.

(a)   Landlord
covenants, warrants and represents that: (i) Landlord is the current holder of the Landlord's interest under the Lease; (ii) each individual
executing, attesting and/or delivering this Agreement on behalf of Landlord is authorized to do so on behalf of Landlord; (iii) this Agreement is binding upon and enforceable against Landlord;
and (iv) Landlord is duly organized and legally existing in the state of its organization and is qualified to do business in the state in which the Premises are located.

(b)   Similarly,
Tenant covenants, warrants and represents that: (i) Tenant is the current holder of the tenant's interest under the Lease and as of the Termination
Date there is no other person or entity occupying or otherwise claiming an interest in the Premises by, through or under Tenant; (ii) each individual executing, attesting and/or delivering this
Agreement on behalf of Tenant is authorized to do so on behalf of Tenant; (iii) this Agreement is binding upon and enforceable against Tenant; and (iv) Tenant is duly organized and
legally existing in the state of its organization and is qualified to do business in the state in which the Premises are located. If there is more than one tenant, or if Tenant is comprised of more
than one party or entity, the obligations imposed upon Tenant shall be joint and several obligations of all the parties and entities. Notices, payments and agreements given or made by, with or to any
one person or entity shall be deemed to have been given or made by, with or to all of them.

11.Consent.    This Agreement is subject to, and conditioned upon, any required
consent or approval being unconditionally granted by Landlord's mortgagees or ground lessors (if applicable). If any such consent shall be denied, or granted subject to a condition unacceptable to
Landlord in Landlord's sole discretion, this Agreement shall be null and void and the Lease shall remain unchanged and in full force and effect.

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

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EXECUTEDby Landlord and Tenant as of the Reference Date.

|LANDLORD: |  | WOODLANDS OFFICE EQUITIES-'95 LIMITED,a Texas limited partnership
|--------- |  | -----------------------------------------------------------------
|          |  | By:                                                              
|          |  |                                                                  
|          |  |                                                                  
|          |  |                                                                  
|          |  |                                                                  
|TENANT:   |  | VALENTIS, INC.,a Delaware corporation                            
|          |  | By:                                                              
|          |  | Name:                                                            
|          |  | Title:                                                           

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EXHIBIT A        LEGAL DESCRIPTION

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EXHIBIT B        STOCK ISSUANCE AND RESTRICTION AGREEMENT

THIS STOCK ISSUANCE AND RESTRICTION AGREEMENT(the "Agreement") is made between Woodlands Office
Equities'95 Limited (the "Holder") and Valentis, Inc., a Delaware corporation (the "Company"), as of August     , 2003 (the "Effective Date").

RECITALS

WHEREAS, pursuant to that certain Lease Termination Agreement, by and between the Holder and the Company, executed
concurrently herewith (the "Lease Termination Agreement"), the Company and the Holder have agreed to enter into this Agreement.

WHEREAS, the Company and the Holder desire to enter into this Agreement, under which the Company will issue the Shares (as defined below)
to the Holder, and the Shares will be subject to a Repurchase Option (as defined below) and other related restrictions on disposition as set forth herein.

NOW, THEREFORE, in consideration of the mutual promises and covenants set forth herein, the parties agree as follows:

Section 1:Issuance of Stock; Delivery.

(a)   Issuance
of Stock. Subject to the terms and conditions of this Agreement, the Company hereby agrees to issue to the Holder 185,000 shares of
the Company's Common Stock, par value $0.001, (the "Shares") in consideration of and subject to the Holder's execution concurrently herewith the Lease Termination Agreement. The issuance of the Shares
shall occur at the principal office of the Company on the date of execution of this Agreement and the Lease Termination Agreement (the "Issuance Date").

(b)   Delivery.
On the Issuance Date, the Company shall deliver to the Holder a certificate representing the Shares against delivery by the Holder
to the Company of the fully executed Lease Termination Agreement, which shall constitute payment therefor.

Section 2:Registration; Restrictions on Transfer

(a)   Restrictions
on Transfer. The Holder agrees that, subject to Section 2(b) of the Agreement, it will not offer, sell, contract to
sell, pledge or otherwise dispose of, (or enter into any transaction which is designed to, or might reasonably be expected to, result in the disposition (whether by actual disposition or effective
economic disposition due to cash settlement or otherwise) by the Holder or by affiliate of the Holder), directly or indirectly, any of the Shares (any such action described in this subsection shall be
referred to in this Agreement as a "Disposition") unless and until the transferee has agreed in writing for the benefit of the Company to be bound by this Section 2, provided and to the extent
such Section is then applicable, and;



Notwithstanding
the provisions of paragraphs (i) and (ii) above, no such registration statement or opinion of counsel shall be necessary for a transfer by the Holder to its
partners or former partners in accordance with partnership interests, provided the transferee will be subject to the terms of this Section 2 to the same extent as if he were an original Holder
hereunder.

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(b)   Legends.
Each certificate representing the Shares shall (unless otherwise permitted by the provisions of this Agreement) be stamped or
otherwise imprinted with a legend substantially similar to the following (in addition to any legend required under applicable state securities laws or as provided elsewhere in this Agreement):



The
legend relating to the Securities Act endorsed on a stock certificate pursuant to this Agreement shall be removed, and the Company shall issue a certificate without such legend to
the holder of the Shares if such shares are registered under the Securities Act and a prospectus meeting the requirements of Section 10 of the Securities Act is available, or if such holder
provides to the Company an opinion of counsel for such holder reasonably satisfactory to the Company to the effect that a public sale, transfer or assignment of such shares may be made without
registration, qualification or legend. Upon removal of such legend, the provisions of Section 2(a) will no longer apply and the transferee of such Shares bearing no legend shall not be subject
to Section 2(a). Notwithstanding any of the forgoing, in no event may the Holder effect a Disposition of any of the Shares which remain subject to the Repurchase Option (as defined below).

Section 3:Repurchase Option.

(a)   Exercise
of Repurchase Option. For a period of two (2) years following the Effective Date for so long as the Shares are subject to
the Company's Repurchase Option (as defined below), the Company shall have an irrevocable, exclusive option, but not the obligation, to repurchase, for any reason or no reason, all or any portion of
the Unreleased Shares (as defined below) from time to time (the "Repurchase Option") at the Repurchase Price (as defined below). The Company may exercise such Repurchase Option and, thereby, purchase
all (or a portion of) the Unreleased Shares by delivering to the Holder in writing a notice of such exercise (the "Repurchase Notice") setting forth the number of Unreleased Shares as of the date of
the Repurchase Notice which the Company wishes to repurchase and the aggregate Repurchase Price for such Unreleased Shares (the "Aggregate Repurchase Price"). Within fifteen (15) days of
delivery by the Company of the Repurchase Notice, payment of the Aggregate Repurchase Price shall be made by check or wire transfer, against delivery of the Unreleased Shares to be repurchased at a
place agreed upon between the parties and at the time of the scheduled closing therefor. Upon the payment of the Aggregate Repurchase Price, the Company shall become the legal and beneficial owner of
the Unreleased Shares being repurchased and all rights and interests therein or relating thereto, and the Company shall have the right to retain and transfer to its own name the number of Unreleased
Shares repurchased by the Company. In the event the Company fails to pay the Aggregate Repurchase Price set forth in the Repurchase Notice within the fifteen (15) day period as required by this
Section 3(a), it is agreed that the Holder's sole and exclusive remedy for such failure shall be that the Company's Repurchase Option shall immediately lapse as to all Unreleased Shares,
whether or not subject to the Repurchase Notice. The Repurchase Option set forth in this Section 3 may be assigned by the Company in whole or in part in its sole and unfettered discretion.

(b)   Lapse
of Repurchase Option. The Shares shall be released from the Company's Repurchase Option as follows:



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Any
of the Shares which, from time to time, have not yet been released from the Repurchase Option are referred to herein as "Unreleased Shares."

(c)   Repurchase
Price. The price for any Shares repurchased under this Section 3 (the "Repurchase Price") shall be the greatest per share
closing sales price of the Company's Common Stock on the date on which the Company delivers the Repurchase Notice, as reported on the Nasdaq Stock Market, the Nasdaq SmallCap Market or the
over-the-counter bulletin board (or if such price is not available, then such other price as determined by the Company's Board of Directors);
provided, however, if the per share price determined in accordance with the foregoing is not at least $9.00 or is greater than $18.00, then
the "Repurchase Price" shall be $9.00 or $18.00, respectively.

(d)   Legend.
The share certificate evidencing the Shares shall be endorsed with the following legend (in addition to any legends required under
this Agreement):



Section 4:Representations and Warranties of the
Holder.The Holder hereby represents and warrants to the Company that as of the Effective Date:

(a)   Holder
Status. The Holder is a limited partnership duly organized and validly existing under the laws of the State of its organization with
power and authority to own its properties and conduct its business. The Holder is not a "broker" or "dealer" as those terms are defined in the Securities Exchange Act of 1934, as amended (the
"Exchange Act"), which is required to be registered with the Securities and Exchange Commission (the "SEC") pursuant to Section 15 of the Exchange Act.

(b)   Authorization
of Transaction. This Agreement has been duly authorized and delivered by the Holder. The Holder has full power and authority
to enter into this Agreement. The Agreement, when executed and delivered by the Holder, will constitute valid and legally binding obligations of the Holder, enforceable in accordance with its terms,
except as limited by applicable bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance and any other laws of general application affecting enforcement of creditors' rights
generally, and as limited by laws relating to the availability of a specific performance, injunctive relief or other equitable remedies.

(c)   Noncontravention.
Neither the execution and the delivery of this Agreement, nor the consummation of the transactions contemplated hereby,
will (i) violate any constitution, statute, regulation, rule, injunction, judgment, order, decree, ruling, charge or other restriction of any government, governmental agency or court to which
the Holder is subject or (ii) conflict with, result in a breach of, constitute a default under, result in the acceleration of, create in any party the right to accelerate, terminate, modify or
cancel, or require any notice under any agreement, contract, lease, license, instrument or other arrangement to which the Holder is a party or by which it is bound or to which any of its assets is
subject.

(d)   Acquisition
Entirely for Own Account. The Shares will be acquired for investment for the Holder's own account (or a trust account if such
Holder is a nominee), not as a nominee or agent, and not with a view to the resale or distribution of any part thereof, and that the Holder has no present intention of selling, granting any
participation in, or otherwise distributing the same. The Holder does not presently have any contract, undertaking, agreement or arrangement with any person or entity to

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sell,
transfer or grant participations to such person or to any third person, with respect to any of the Shares. The Holder has not been formed for the specific purpose of acquiring solely the Shares.

(e)   Experience;
Accredited Investor. The Holder has experience as an investor in securities of companies in the developmental stage and
acknowledges that it can bear the economic risk of its investment in the Shares. The Holder, by reason of its business or financial experience or the business or financial experience of its
professional advisors who are unaffiliated with and who are not compensated by the Company or any affiliate or selling agent of the Company, directly or indirectly, has the capacity to protect its own
interests in connection with its purchase of the Shares. The Holder has the financial capacity to bear the risk of this investment. The Holder is an accredited investor as defined in
Rule 501(a) of Regulation D promulgated under the Securities Act.

(f)    Limitations
on Dispositions. The Holder understands that the Shares are "restricted securities" under applicable United States federal and
state securities laws and that, pursuant to these laws, the Holder must hold the Shares indefinitely unless they are registered with the SEC and qualified by state authorities, or an exemption from
such registration and qualification requirements is available. The Holder acknowledges that the Company will make a notation on its stock books regarding the restrictions on transfers set forth in
this Agreement and will transfer securities on the books of the Company only to the extent not inconsistent therewith.

(g)   Information
Provided. The Holder and its advisors, if any, have requested, received and considered all information contained in the
Company's Annual Report on Form 10-K for the fiscal year ended June 30, 2002, the Company's Quarterly Reports on Form 10-Q for the quarters ended
September 30, 2002, December 31, 2002, and March 31, 2003, and the Company's definitive proxy statements for the Annual Meeting of Stockholders held on January 23, 2003,
and the Special Meeting of Stockholders held on May 29, 2003, in each case as filed with the SEC and as amended to date and including the information and documents (other than exhibits)
incorporated therein by reference (the "SEC Reports"). The Holder and its advisors, if any, have been afforded the opportunity to ask questions of the Company concerning the Shares and the business,
properties, operations, condition (financial or other), and results of operations of the Company. In connection with its decision to acquire the Shares, the Holder has relied solely upon the SEC
Reports. The Holder understands that its investment in the Shares involves a high degree of risk.

(h)   Company
Reliance. The Holder understands that the Shares will be issued to the Holder in reliance on one or more exemptions from the
registration requirements of the Securities Act, including, without limitation, Regulation D under the Securities Act, and exemptions from state securities laws and that the Company is relying
upon the truth and accuracy of, and the Holder's compliance with, the representations, warranties, agreements, acknowledgments and understandings of the Holder set forth in this Agreement in order to
determine the availability of such exemptions and the eligibility of the Holder to acquire the Shares.

(i)    Absence
of Approvals. The Holder understands that no United States federal or state agency or any other government or governmental agency
has passed on or made any recommendation or endorsement of the Shares.

(j)    Absence
of Reliance. The Holder acknowledges that, other than as expressly set forth in this Agreement, neither the Company nor its advisors
have made, and the Holder has not relied upon, any representation or warranty as to the merits of an investment in the Shares or the income tax consequences to the Holder of the transactions
contemplated by this Agreement.

Section 5:Representations and Warranties of the
Company.

(a)   Company
Status. The Company has been duly incorporated and is an existing corporation in good standing under the laws of the State of
Delaware with power and authority (corporate and other) to own its properties and conduct its business as described in the SEC Reports; and the Company is

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duly
qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such
qualification.

(b)   Authorization
of Shares. The Shares have been duly authorized and validly issued and, when the Shares have been delivered to Holder in
accordance with this Agreement, such Shares will be fully paid and nonassessable. The Shares and all other outstanding shares of capital stock of the Company conform to the description thereof
contained or incorporated in the SEC Reports; and the stockholders of the Company have no preemptive rights with respect to the Shares.

(c)   Share
Quotation. The Company's Common Stock has been approved for quotation on the Nasdaq SmallCap Market pursuant to an exception as
described in the SEC Reports.

(d)   Required
Consents. No consent, approval, authorization, or order of, or filing with, any governmental agency or body or any court is
required to be obtained or made by the Company for the consummation of the transactions contemplated by this Agreement in connection with the issuance of the Shares, except such as have been obtained
and made under the Securities Act and such as may be required under state securities laws.

(e)   Authorization
of Transaction. This Agreement has been duly authorized, executed and delivered by the Company. The Company has full power and
authority to enter into this Agreement. The Agreement, when executed and delivered by the Company, will constitute valid and legally binding obligations of the Company, enforceable in accordance with
its terms, except as limited by applicable bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance and any other laws of general application affecting enforcement of creditors'
rights generally, and as limited by laws relating to the availability of a specific performance, injunctive relief or other equitable remedies.

(f)    Noncontravention.
Neither the execution and the delivery of this Agreement, nor the consummation of the transactions contemplated hereby,
will (i) violate any constitution, statute, regulation, rule, injunction, judgment, order, decree, ruling, charge or other restriction of any government, governmental agency or court to which
the Company is subject or (ii) conflict with, result in a breach of, constitute a default under, result in the acceleration of, create in any party the right to accelerate, terminate, modify or
cancel, or require any notice under any agreement, contract, lease, license, instrument or other arrangement to which the Company is a party or by which it is bound or to which any of its assets is
subject.

Section 6:Registration Rights.

(a)   Certain
Definitions. For purposes of this Agreement:



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(b)   Piggyback
Registrations. On or after September 20, 2004, the Company shall be obligated to notify the Holder in writing at least
thirty (30) days prior to the filing of any registration statement under the Securities Act for purposes of a public offering of securities of the Company (including, but not limited to,
registration statements relating to secondary offerings of securities of the Company, but excluding registration statements relating to employee benefit plans and corporate reorganizations) and will
afford such Holder an opportunity to include in such registration statement all or part of such Registrable Securities held by such Holder. If the Holder desires to include in any such registration
statement all or any part of the Registrable Securities held by it, it shall, within fifteen (15) days after receipt of the above-described notice from the Company, so notify the Company in
writing. Such notice shall state the intended method of disposition of the Registrable Securities by such Holder. If the Holder decides not to include all of its Registrable Securities in any
registration statement thereafter filed by the Company, such Holder shall nevertheless continue to have the right to include any Registrable Securities in any subsequent registration statement or
registration statements as may be filed by the Company with respect to offerings of its securities, all upon the terms and conditions set forth herein.



(c)   Form S-3
Registration. On or after the second anniversary of the Effective Date, if the Company receives from the Holder
a written request that the Company effect a registration on Form S-3 and any related qualification or compliance with respect to all or a part of the Registrable Securities owned by
such Holder, the Company will, as soon as practicable, and consistent with the requirements of applicable law, prepare and file with the SEC a registration statement on Form S-3 for
an offering to be made on a continuous basis pursuant to Rule 415 covering all of the then outstanding Registrable Securities (the "Shelf Registration"). The Company shall use its commercially
reasonable efforts to have such Shelf Registration declared effective as soon as practicable thereafter (with the objective, but not the obligation, of causing the Shelf Registration to be declared
effective within sixty (60) days after it has been filed with the SEC) and to keep such Shelf Registration continuously

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effective
under the Securities Act for up to one hundred eighty (180) days; provided, however, that the Company shall not be obligated
to effect any such registration, qualification or compliance pursuant to this Section 6(c): (i) if Form S-3 is not available for such offering by the Holder;
(ii) if the Holder proposes to sell Registrable Securities of less than 100,000 shares (as adjusted for stock splits, stock dividends, recapitalizations and the like); (iii) if the
Company shall furnish to the Holder a certificate signed by the Chairman of the Board of Directors of the Company stating that in the good faith judgment of the Board of Directors of the Company, it
would be seriously detrimental to the Company and its shareholders for such Form S-3 Registration to be effected at such time, in which event the Company shall have the right to
defer the filing of the Form S-3 registration statement for a period of not more than ninety (90) days after receipt of the request of the Holder under this
Section 6(c); or (iv) in any particular jurisdiction in which the Company would be required to qualify to do business or to execute a general consent to service of process in effecting
such registration, qualification or compliance.



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(d)   Expenses
of Registration. All expenses other than underwriting discounts and commissions incurred in connection with registrations initiated
pursuant to Section 6(b) and Section 6(c), including (without limitation) all registration, filing and qualification fees, printers' and accounting fees, fees and disbursements of
counsel for the Company, and the reasonable fees and disbursements of up to $20,000 of one counsel for the Holder selected by Holder with the approval of the Company, which approval shall not be
unreasonably withheld, shall be borne by the Company; provided, however, that the Company shall not be required to pay for any expenses of any
registration proceeding begun pursuant to Section 6(c) if the registration request is subsequently withdrawn at the request of the Holder.

(e)   Obligations
of the Company. Whenever required to effect the registration of any Registrable Securities, the Company shall use its best
efforts, as expeditiously as reasonably possible, to:



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(f)    Termination
of Registration Rights. The Holder shall not be entitled to exercise any registration right provided for in this
Section 6 after the earlier of (i) three (3) years following the Effective Date; (ii) such time as Rule 144 or another similar exemption under the Securities Act is
available for the sale of all of the Registrable Securities; or (iii) an acquisition of the Company by another entity by means of any transaction or series of related transactions (including,
without limitation, any reorganization, merger or consolidation, but excluding any (x) consolidation with a wholly owned subsidiary of the Company and (y) merger effected exclusively for
the purpose of changing the domicile of the Company), or a sale of all or substantially all of the assets of the Company, unless the Company's stockholders of record as constituted immediately prior
to such acquisition or sale will, immediately after such acquisition or sale (by virtue of securities issued as consideration for the Company's acquisition or sale or otherwise) hold at least 50% of
the voting power of the surviving or acquiring entity in approximately the same relative percentages after such acquisition or sale as before such acquisition or sale.

(g)   Delay
of Registration. The Holder shall not have any right to obtain or seek an injunction restraining or otherwise delaying any such
registration as the result of any controversy that might arise with respect to the interpretation or implementation of this Section 6.

(h)   Indemnification.
In the event any Registrable Securities are included in a registration statement under this Section 6:



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(i)    Rule 144.
With a view to making available to the Holder the benefits of certain rules of the SEC that may permit the sale of Shares
not subject to the Repurchase Option to the public without registration, the Company hereby covenants and agrees so long as the Holder holds the Shares to use its best efforts to: (i) file in a
timely manner all reports and other documents required to be filed by it under the Securities Act and the Exchange Act and the rules and regulations adopted by the SEC thereunder necessary to permit
sales pursuant to Rule 144 under the Securities Act, and the Company will take such further action to the extent required from time to time to enable the Holder to sell the Shares not subject
to the Repurchase Option without registration under the Securities Act within the limitation of the exemptions provided by (a) Rule 144 under the Securities Act, as such Rule may be
amended from time to time, or (b) any similar rule or regulation hereafter adopted by the SEC and (ii) promptly furnish the Holder, upon request, a copy of all such reports and
documents. Upon the written request of the Holder, the Company will deliver to the Holder a written statement as to whether the Company has complied with such requirements.

Section 7:Miscellaneous.

(a)   Ownership,
Voting Rights. This Agreement shall not affect in any way the ownership, voting rights or other rights of the Holder, except as
specifically provided herein.

(b)   Adjustment
for Stock Splits. All references to the number of Shares and the purchase price of the Shares in this Agreement shall be
appropriately adjusted to reflect any stock split, stock dividend or other change in the Shares which may be made by the Company after the Effective Date.

(c)   Notices.
Notices required or permitted hereunder shall be given in person or by registered mail to the address of the Holder shown on the
records of the Company, and to the Company at its principal executive office and shall be in writing and shall be deemed effectively given: (i) upon personal delivery to the party to be
notified; (ii) when sent by facsimile if sent during normal business hours of the recipient; if not, then on the next business day; (iii) five (5) days after having been sent by
registered or certified mail, return receipt requested, postage prepaid; or (iv) one (1) day after deposit with a nationally recognized overnight courier, specifying next day delivery,
with written verification of receipt.

(d)   Survival
of Terms. This Agreement shall apply to and bind the Holder and the Company and their respective permitted assignees and
transferees, heirs, legatees, executors, administrators and legal successors.

(e)   Governing
Law; Severability. This Agreement shall be governed by and construed in accordance with the laws of the State of California
excluding that body of law pertaining to conflicts of

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law.
Should any provision of this Agreement be determined by a court of law to be illegal or unenforceable, the other provisions shall nevertheless remain effective and shall remain enforceable.

(f)    Entire
Agreement. This Agreement and the Lease Termination Agreement set forth the entire agreement of the parties hereto in respect of the
subject matter contained herein and therein and supersede all prior agreements, promises, covenants, arrangements, communications, representations or warranties, whether oral or written, by any
officer, employee or representative of any party hereto, and any prior agreement of the parties hereto in respect of the subject matter contained herein.

[Signature
page follows]

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EXECUTEDby the Holder and the Company as of the date first set forth above.

|HOLDER:  |  | WOODLANDS OFFICE EQUITIES-'95 LIMITED,a Texas limited partnership
|-------- |  | -----------------------------------------------------------------
|         |  | By:                                                              
|         |  |                                                                  
|         |  |                                                                  
|         |  |                                                                  
|         |  |                                                                  
|COMPANY: |  | VALENTIS, INC.,a Delaware corporation                            
|         |  | By:                                                              
|         |  | Name:                                                            
|         |  | Title:                                                           

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