Document:

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                                                                   EXHIBIT 10.28

                ADMINISTRATIVE SERVICES AND MANAGEMENT AGREEMENT

This Administrative Services and Management Agreement (this "Agreement"),
effective as of January 1, 1999 (the "Effective Date"), is entered into by and
between Introgen Therapeutics, Inc., a Delaware corporation ("Introgen"), and
Gendux, Inc., a Delaware corporation ("Gendux").

                                   BACKGROUND

         A. Introgen and Gendux are parties to that certain Delivery Technology
License Agreement of even date herewith (the "DTLA") pursuant to which Introgen
licensed certain technology and rights to Gendux, that certain Target Gene
License Agreement of even date herewith (the "TGLA") pursuant to which Introgen
licensed certain genes and rights to Gendux, and that certain Research and
Development Agreement of even date herewith (the "Development Agreement")
pursuant to which Introgen has agreed to assist Gendux in performing a certain
developmental research program within the Field; and

         B. Gendux desires that Introgen provide certain administrative and
management services to Gendux in addition to assisting Gendux in performing such
developmental research program under the Development Agreement, and Introgen
desires to provide such administrative and management services, on the terms set
forth herein below.

         NOW, THEREFORE, in consideration of the mutual covenants expressed
herein and for other good and valuable consideration; the receipt and adequacy
of which are hereby acknowledged, the parties agree as follows:

1 DEFINITIONS.

         1.1 "Affiliate" shall mean any entity which controls, is controlled by
or is under common control with Introgen or Gendux. For purposes of this
definition, "control" shall mean beneficial ownership (direct or indirect) of at
least fifty percent (50%) of the shares of the subject entity entitled to vote
in the election of directors (or, in the case of an entity that is not a
corporation, for the election of the corresponding managing authority).
Notwithstanding the foregoing, neither Introgen nor Gendux shall be deemed to be
an Affiliate of the other for purposes of this Agreement.

         1.2 "First Financing" shall mean the closing of the sale and/or
issuance of equity and/or debt securities by Gendux, as a result of which the
cumulative total of cash proceeds from such financings received by Gendux
exceeds [*].

         1.3 "GAAP" shall mean generally accepted accounting principles in the
United States.

         [*]    Certain information on this page has been omitted and filed
                separately with the Commission. Confidential treatment has been
                requested with respect to the omitted portions.
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         1.4 "Reimbursable Costs" shall mean the direct and indirect costs
incurred by or on behalf of Introgen in performing Services hereunder, all as
calculated using GAAP.

         1.5 "Services" shall have the meaning as set forth in Section 2.1
below.

2 SERVICES TO BE PROVIDED.

         2.1 Services. Gendux hereby engages Introgen to provide, or arrange to
provide, to Gendux general, administrative and management services, including,
without limitation, the services described generally below (collectively,
"Services"). Introgen agrees to use its diligent efforts to provide specific
Services, at the times and in the manner in which Introgen deems necessary or
appropriate to effect the day-to-day business operations of Gendux:

                  2.1.1 General. Advice and services with respect to accounting
and financial matters, marketing, government and public relations, industrial
relations, personnel and human resource administration, employee benefits
administration, procurement, purchasing, inventory control, business
development, corporate partnering, planning and investigation, management
information systems, facilities occupancy (including renting, leasing and
maintaining), administrative matters and insurance;

                  2.1.2 Treasury. Treasury services, including, but not limited
to, opening and maintaining bank accounts, reconciling bank accounts to
accounting records, disbursing funds for goods, services and payroll either by
check or electronically, collection and deposit of funds, general money
management assistance (including investing funds in interest bearing accounts or
instruments), and preparation of cash flow budgets and forecasts;

                  2.1.3 Finance, Accounting and Recordkeeping. Finance,
accounting and recordkeeping services, including but not limited to, design and
implementation of accounting policies, procedures and internal controls, general
ledger and related subledger maintenance, transaction processing, financial
statement preparation, tax return preparation and filing, coordination with
independent accountants and auditors, maintenance of stockholder records, and
maintenance of records of meetings of the board of directors and director and
related committees;

                  2.1.4 Recruiting. Advice and services with respect to
selection, recruiting, supervision and evaluation of personnel;

                  2.1.5 Legal. Advice and services with respect to intellectual
property, regulatory, legal and tax matters, including, without limitation,
filings and hearings before foreign, federal, state and municipal agencies or
authorities; and

                  2.1.6 Other. Such other advice and services as are reasonably
requested by Gendux in order to carry out the day-to-day business operations of
Gendux.

         2.2 Standard of Care. In providing Services hereunder, Introgen shall
use, and Gendux hereby agrees to accept in all respects, the same standard of
skill and care that Introgen uses in the course of undertaking similar services
for itself. To the extent reasonably possible, such services shall

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be substantially identical in nature and quality to similar services currently
provided or otherwise obtained by Introgen on its own behalf.

         2.3 Introgen Activities. Gendux hereby acknowledges that Introgen's
business interests, activities, and opportunities are and will continue to be
substantially similar to the interests, activities and opportunities of Gendux.
Gendux further acknowledges that Introgen will pursue such interests, activities
and opportunities of Introgen for its own account and/or the account of others.
Gendux agrees that Introgen may pursue Introgen's business interests, activities
and opportunities without any obligation to offer any such interests, activities
or opportunities to Gendux, except as expressly provided under the DTLA or the
TGLA. Gendux further agrees that it shall not have any rights by virtue of this
Agreement or the relationship created hereby in any such business interests,
activities or opportunities. Introgen agrees to keep the Gendux Board of
Directors duly informed of its activities under this Agreement.

         2.4 Approval of Contracts and Commitments. Prior to making or entering
into any written commitment or contract on behalf of Gendux that involves: (i)
obligations of, or payments by, Gendux in excess of [*] or (ii) the grant of
[*], Introgen shall first obtain the written approval of Gendux.

         2.5 Commitment of Resources. It is understood that Gendux is entering
into this Agreement, the DTLA, the TGLA and the Development Agreement in
reliance upon the commitment by Introgen to make available the services of a
management team, which team consists of [*] (or such other representatives as
Introgen reasonably designates from time to time), to provide and oversee
appropriate Services under this Agreement. Without limiting any other provision
of this Agreement, so long as the members of such management team remain
employed by Introgen, Introgen will use commercially reasonable efforts to
provide that such individuals are available to perform the Services, as
appropriate, to be provided by Introgen hereunder.

         2.6 Subcontracting. Subject to Gendux's written consent, which consent
shall not be unreasonably withheld or delayed, Introgen may engage third parties
to perform all or any portion of the Services hereunder; provided, however, that
no such consent shall be required for the engagement by Introgen of any third
party to perform such Services if Introgen customarily engages third parties to
perform similar services for itself.

3 REIMBURSABLE COSTS.

         3.1 Reimbursable Costs. During the term of this Agreement, Gendux shall
reimburse Introgen for its Reimbursable Costs. It is understood that the
Reimbursable Costs will include without limitation amounts paid to consultants
or third-party service providers or the like. In addition, Reimbursable Costs
may include costs for equipment and facilities acquired for purposes of the
Services; provided that if such equipment or facilities are used both (i) in the
course of providing Services to Gendux and (ii) for other purposes (including
providing services to Introgen), then the costs of such equipment or facilities
shall be allocated between the Services and such other purposes in accordance
with GAAP. It is understood that if Introgen acquires any capital equipment or
facilities in

      [*] Certain information on this page has been omitted and filed
          separately with the Commission. Confidential treatment has been
          requested with respect to the omitted portions.

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connection with the Services, Introgen shall own all such capital equipment and
facilities, unless the parties otherwise agree.

         3.2 Management Fee. In addition to the Reimbursable Costs set forth in
Section 3.1 above and in consideration of the services of Introgen's management
team as set forth in Article 2 above, Gendux shall pay to Introgen an annual
management fee, which fee shall be equal to [*] per annum for the 1999 through
2000 calendar years and shall accrue from the date of the First Financing. The
amount of such management fee for subsequent calendar years is subject to
adjustment on an annual basis and shall be agreed upon by Introgen and the Board
of Directors of Gendux by no later than October 1 of the preceding year. Gendux
shall pay [*] of each such annual management fee to Introgen [*] during the term
of this Agreement. In the event this Agreement is terminated prior to the end of
any calendar year, such management fee shall be prorated for the number of days
that Introgen actually performs services, based on the number of days in such
year.

         3.3 First Financing Payment. Upon the closing of the First Financing,
Gendux shall pay to Introgen an amount equal to Gendux's share of Reimbursable
Costs and organizational costs incurred by Introgen, on behalf of Gendux, prior
to the First Financing. For such purposes, "organizational costs" shall include
out of pocket costs associated with (i) the establishment and organization of
Gendux, (ii) the R&D Program (as defined in the Development Agreement) and (iii)
the acquisition, maintenance and protection of rights to the Subject Genes (as
defined in the TGLA) and the Licensed Technology (as defined in the DTLA)
(including patent costs); in each case which were incurred prior to the First
Financing. It is understood that such organizational costs shall not exceed [*].

         3.4 Payment Method. Unless otherwise specified herein, all payments
hereunder shall be due and payable thirty (30) days after invoicing therefor.
All payments under this Agreement shall be made by bank wire transfer in
immediately available funds to an account designated by Introgen, or as
otherwise agreed. All dollar amounts specified in this Agreement, and all
payments made hereunder, are and shall be made in U.S. dollars. Any payments due
under this Agreement which are not paid by the date such payments are due under
this Agreement shall bear interest to the extent permitted by applicable law at
[*], calculated on the number of days such payment is delinquent. This Section
3.4 shall in no way limit any other remedies available to either party.

4 REPRESENTATIONS AND WARRANTIES.

         4.1 Representations and Warranties of Introgen. Introgen represents and
warrants to Gendux as follows:

                  4.1.1 Introgen is a corporation duly organized, validly
existing and in good standing under the laws of the State of Delaware with
corporate powers adequate for executing and delivering, and performing its
obligations under, this Agreement;

      [*] Certain information on this page has been omitted and filed
          separately with the Commission. Confidential treatment has been
          requested with respect to the omitted portions.

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                  4.1.2 the execution, delivery and performance of this
Agreement have been duly authorized by all necessary corporate action on the
part of Introgen;

                  4.1.3 this Agreement has been duly executed and delivered by
Introgen and is a legal, valid and binding obligation of Introgen, enforceable
against Introgen in accordance with its terms; and

                  4.1.4 the execution, delivery and performance of this
Agreement do not conflict with or contravene any provision of the charter
documents or bylaws of Introgen or any agreement, document, instrument,
indenture or other obligation of Introgen.

         4.2 Representations and Warranties of Gendux. Gendux represents and
warrants to Introgen as follows:

                  4.2.1 Gendux is a corporation duly organized, validly existing
and in good standing under the laws of Delaware with corporate powers adequate
for executing and delivering, and performing its obligations under, this
Agreement;

                  4.2.2 the execution, delivery and performance of this
Agreement have been duly authorized by all necessary corporate action on the
part of Gendux;

                  4.2.3 this Agreement has been duly executed and delivered by
Gendux and is a legal, valid and binding obligation of Gendux, enforceable
against Gendux in accordance with its terms; and

                  4.2.4 the execution, delivery and performance of this
Agreement do not conflict with or contravene any provision of the charter
documents or bylaws of Gendux or any agreement, document, instrument, indenture
or other obligation of Gendux.

         4.3 Disclaimer. EXCEPT AS OTHERWISE EXPLICITLY PROVIDED IN THIS ARTICLE
4, INTROGEN AND GENDUX EXPRESSLY DISCLAIM ANY WARRANTIES OR CONDITIONS, EXPRESS,
IMPLIED, STATUTORY OR OTHERWISE, WITH RESPECT TO THE SERVICES, INCLUDING,
WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY, NONINFRINGEMENT, OR FITNESS
FOR A PARTICULAR PURPOSE.

5 CONFIDENTIALITY AGREEMENTS.

         Introgen and Gendux hereby agree that they will have each of their
respective employees, consultants and officers who have access to confidential
or proprietary information of the other party execute a confidential information
and nondisclosure agreement in form and substance reasonably satisfactory to
such other party.

6 INDEPENDENT CONTRACTOR.

         All debts and liabilities of and arrangements or agreements with any
person or entity incurred or entered into in the name of or on behalf of Gendux
by Introgen in the management or performance of the Services hereunder in
accordance with this Agreement shall be the debt and liability of and be binding
upon Gendux. Introgen shall not be liable to any person or entity for any debt,
liability or

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obligation of Gendux incurred or created in accordance with this Agreement or by
reason of Introgen's management, direction or performance of the Services
hereunder unless Introgen, by written agreement, expressly assumes or guarantees
any such liability. Introgen shall not be required, under any circumstances, to
guarantee or assume any obligation or liability of Gendux as a result of this
Agreement. Gendux's Board of Directors shall be deemed to control all aspects of
the manner in which Gendux's business is conducted. Introgen shall not be liable
by virtue of the performance of its duties hereunder for any breach of any
arrangement between Gendux and any third party, or for any liability for any
unfair competition, patent infringement or other violation of the intellectual
property rights of another entity as a result of the manner in which Gendux's
business is conducted, except to the extent such violation is the result of the
gross negligence or willful misconduct of Introgen.

7 INDEMNIFICATION.

         7.1 Indemnification of Introgen. Subject to Section 7.3 below, Gendux
shall indemnify each of Introgen and its Affiliates and the directors, officers,
and employees of Introgen and such Affiliates and the successors and assigns of
any of the foregoing (the "Introgen Indemnitees"), and hold each Introgen
Indemnitee harmless from and against any and all liabilities, damages,
settlements, claims, actions, suits, penalties, fines, costs or expenses
(including, without limitation, reasonable attorneys' fees and other expenses of
litigation) incurred by any Introgen Indemnitee as a result of a claim by a
third party brought against any Introgen Indemnitee of whatever kind or nature,
including, without limitation, any claim or liability based upon negligence,
warranty, strict liability, violation of government regulation or infringement
of patent, copyright, trademark, trade secret or other proprietary rights,
arising from or occurring as a result of the Services provided by Introgen to
Gendux under this Agreement, except claims based upon the gross negligence or
willful misconduct of Introgen in providing the Services hereunder in accordance
with this Agreement.

         7.2 Indemnification of Gendux. Subject to Section 7.3 below, Introgen
shall indemnify each of Gendux and its Affiliates and the directors, officers,
and employees of Gendux and such Affiliates and the successors and assigns of
any of the foregoing (the "Gendux Indemnitees"), and hold each Gendux Indemnitee
harmless from and against any and all liabilities, damages, settlements, claims,
actions, suits, penalties, fines, costs or expenses (including, without
limitation, reasonable attorneys' fees and other expenses of litigation)
incurred by any Gendux Indemnitee as a result of a claim by a third party
brought against any Gendux Indemnitee arising from or occurring as a result of
the gross negligence or willful misconduct of Introgen hereunder.

         7.3 Procedure. A party (the "Indemnitee") that intends to claim
indemnification under this Article 7 shall: (i) promptly notify the indemnifying
party (the "Indemnitor") in writing of any claim, action, suit, or other
proceeding brought by third parties in respect of which the Indemnitee or any of
its Affiliates, or their directors, officers, employees, successors or assigns
intend to claim such indemnification hereunder; (ii) provide the Indemnitor sole
control of the defense and/or settlement thereof, and (iii) provide the
Indemnitor, at the Indemnitor's request and expense, with reasonable assistance
and full information with respect thereto. Indemnitor shall not settle any
claim, suit or proceeding subject to this Article 7 or otherwise consent to an
adverse judgment in such claim, suit or proceeding if the same materially
diminishes the rights or interests of the Indemnitee without the express written
consent of the Indemnitee. Notwithstanding the foregoing, the indemnity
agreement in this

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Article 7 shall not apply to amounts paid in settlement of any loss, claim,
damage, liability or action if such settlement is effected without the consent
of the Indemnitor, to the extent such consent is not unreasonably withheld or
delayed. Notwithstanding anything herein to the contrary, the Indemnitee shall
have the right to participate in any such claim, suit or proceeding with counsel
of its choosing at its own expense.

8 TERM AND TERMINATION.

         8.1 Term and Termination for Convenience. The term of this Agreement
shall commence on the Effective Date and continue thereafter in full force and
effect until terminated by either party, for any reason or for no reason, upon
one hundred eighty (180) days prior written notice to the other party, or unless
terminated in accordance with the other provisions of this Article 8.

         8.2 Termination for Breach. In the event of a material breach of this
Agreement, the nonbreaching party shall be entitled to terminate this Agreement
by written notice to the breaching party, if such breach is not cured within
thirty (30) days after written notice is given by the nonbreaching party to the
breaching party specifying the breach. Notwithstanding the foregoing, if the
party alleged to be in breach of this Agreement disputes such breach within such
thirty (30) day period, the nonbreaching party shall not have the right to
terminate this Agreement unless it has been determined by a court of competent
jurisdiction that this Agreement was materially breached, and the breaching
party fails to comply with its obligations hereunder within thirty (30) days
after such determination.

         8.3 Termination of the Development Program. Either party may terminate
this Agreement on written notice in the event of termination of the R&D Program
in accordance with Section 8.1 of the Development Agreement.

         8.4 Survival.

                  8.4.1 Accrued Obligations. Termination of this Agreement for
any reason shall not release either party hereto from any liability which at the
time of such termination has already accrued to the other party.

                  8.4.2 Other. Articles 1, 6, 7 and 9 and Sections 4.3 and 8.4
shall survive the expiration and any termination of this Agreement. Except as
otherwise provided in this Article 8, all rights and obligations of the parties
under this Agreement shall terminate upon the expiration or termination of this
Agreement.

9 MISCELLANEOUS.

         9.1 Governing Law. This Agreement and any dispute arising from the
performance or breach hereof shall be governed by and construed and enforced in
accordance with, the laws of the State of Texas, without reference to conflicts
of laws principles.

         9.2 Force Majeure. Nonperformance of any party (except for payment of
amounts due hereunder) shall be excused to the extent that performance is
rendered impossible by strike, fire, earthquake, flood, governmental acts or
orders or restrictions, or any other reason, including failure of

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suppliers, where failure to perform is beyond the reasonable control of the
nonperforming party. Without limiting the foregoing, the party subject to such
inability shall use reasonable efforts to minimize the duration of any force
majeure event.

         9.3 No Implied Waivers; Rights Cumulative. No failure on the part of
Introgen or Gendux to exercise and no delay in exercising any right under this
Agreement, or provided by statute or at law or in equity or otherwise, shall
impair, prejudice or constitute a waiver of any such right, nor shall any
partial exercise of any such right preclude any other or further exercise
thereof or the exercise of any other right.

         9.4 Notices. All notices, requests and other communications hereunder
shall be in writing and shall be personally delivered or sent by registered or
certified mail, return receipt requested, postage prepaid; facsimile
transmission (receipt verified); or express courier service (signature
required), in each case to the respective address or fax number specified below,
or such other address or fax number as may be specified in writing to the other
parties hereto:

<TABLE>
<S>                                         <C>
              Gendux:                       Gendux, Inc.
                                            301 Congress Avenue, Suite 1850
                                            Austin, Texas 78701
                                            Attn: President
                                            Fax: (512) 708-9311

              with copy to:                 Wilson Sonsini Goodrich & Rosati
                                            Professional Corporation
                                            650 Page Mill Road
                                            Palo Alto, California 94304-1050
                                            Attn: Kenneth A. Clark, Esq.
                                            Fax:  (650) 493-6811

              Introgen:                     Introgen Therapeutics, Inc.
                                            301 Congress Avenue, Suite 1850
                                            Austin, Texas 78701
                                            Attn: President
                                            Fax: (512) 708-9311

              with a copy to:               Wilson Sonsini Goodrich & Rosati
                                            Professional Corporation
                                            650 Page Mill Road
                                            Palo Alto, California 94304-1050
                                            Attn: Kenneth A. Clark, Esq.
                                            Fax:  (650) 493-6811
</TABLE>

         9.5 Limitation of Liability. NEITHER PARTY SHALL BE LIABLE TO THE OTHER
PARTY FOR ANY SPECIAL, CONSEQUENTIAL, EXEMPLARY OR INCIDENTAL DAMAGES

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(INCLUDING LOST OR ANTICIPATED REVENUES OR PROFITS RELATING TO THE SAME),
ARISING FROM ANY CLAIM RELATING TO THIS AGREEMENT, WHETHER SUCH CLAIM IS BASED
ON CONTRACT, TORT (INCLUDING NEGLIGENCE) OR OTHERWISE, EVEN IF AN AUTHORIZED
REPRESENTATIVE OF SUCH PARTY IS ADVISED OF THE POSSIBILITY OR LIKELIHOOD OF
SAME.

         9.6 Assignment. This Agreement shall not be assignable by either party
to any third party without the written consent of the other party hereto; except
that either party may assign this Agreement without the other party's consent to
an entity that acquires substantially all of the business or assets of the
assigning party, in each case whether by merger, transfer of assets, or
otherwise. Upon a permitted assignment of this Agreement, all references herein
to the assigning party shall be deemed references to the party to whom the
Agreement is so assigned. Any assignment not permitted under this Section 10.6
shall be null and void.

         9.7 Modification. No amendment or modification of any provision of this
Agreement shall be effective unless in writing signed by both parties hereto. No
provision of this Agreement shall be varied, contradicted or explained by any
oral agreement, course of dealing or performance or any other matter not set
forth in an agreement in writing and signed by both parties hereto.

         9.8 Severability. If any provision hereof should be held invalid,
illegal or unenforceable in any jurisdiction, the parties shall negotiate in
good faith a valid, legal and enforceable substitute provision that most nearly
reflects the original intent of the parties and all other provisions hereof
shall remain in full force and effect in such jurisdiction and shall be
liberally construed in order to carry out the intentions of the parties hereto
as nearly as may be possible. Such invalidity, illegality or unenforceability
shall not affect the validity, legality or enforceability of such provision in
any other jurisdiction.

         9.9 Confidential Terms. Except as expressly provided herein, each party
agrees not to disclose any terms of this Agreement to any third party without
the consent of the other party, except as required by securities or other
applicable laws, to prospective and other investors and such party's
accountants, attorneys and other professional advisors.

         9.10 Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, and both of which
together shall constitute one and the same instrument.

         9.11 Headings. Headings used herein are for convenience only and shall
not in any way affect the construction of or be taken into consideration in
interpreting this Agreement.

         9.12 Entire Agreement. This Agreement, together with the DTLA, the TGLA
and the Development Agreement (including the respective Exhibits thereto), each
entered into by the parties of even date, constitute the entire agreement, both
written or oral, with respect to the subject matter hereof, and supersede all
prior or contemporaneous understandings or agreements, whether written or oral,
between Introgen and Gendux with respect to such subject matter.

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         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed and delivered in duplicate originals as of the date first above
written.

INTROGEN THERAPEUTICS, INC.

By: /s/ James W. Albrecht, Jr.
   ------------------------------------
Name: James W. Albrecht, Jr.
     ----------------------------------
Title: Chief Financial Officer
      ---------------------------------

GENDUX, INC.

By: /s/ David G. Nance
   ------------------------------------
Name: David G. Nance
     ----------------------------------
Title: President and CEO
      ---------------------------------<PAGE>   1
                                                                   EXHIBIT 10.29

                       RESEARCH AND DEVELOPMENT AGREEMENT

     This Research and Development Agreement (this "Agreement"), effective as of
January 1, 1999 (the "Effective Date"), is entered into by and between Introgen
Therapeutics, Inc., a Delaware corporation ("Introgen"), and Gendux, Inc., a
Delaware corporation ("Gendux").

                                   BACKGROUND

     A.   Introgen and Gendux are parties to the Delivery Technology License
Agreement (all capitalized terms used but not defined herein shall have the
respective meanings set forth in Section 1 hereof) pursuant to which Introgen
licensed certain technology and rights to Gendux, the Target Gene License
Agreement pursuant to which Introgen granted to Gendux rights in certain genes,
and the Services Agreement pursuant to which Gendux engaged Introgen to provide
administrative and management services; and

     B.   In connection with the Delivery Technology License Agreement and the
Target Gene License Agreement, Gendux desires that Introgen assist Gendux in
performing a certain developmental research program, and Introgen desires to
assist Gendux in performing such developmental research program, on the terms
set forth herein below.

     NOW, THEREFORE, in consideration of the mutual covenants, conditions and
undertakings herein contained and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, and in order to induce
Introgen to enter into the Delivery Technology License Agreement and the Target
Gene License Agreement, the parties hereto agree as follows:

     Section 1. Definitions. As used herein, capitalized terms shall have the
respective meanings set forth below:

          1.1  "Affiliate" shall mean any entity which controls, is controlled
by or is under common control with Introgen or Gendux. For purposes of this
definition, "control" shall mean beneficial ownership (direct or indirect) of
more than fifty percent (50%) of the shares of the subject entity entitled to
vote in the election of directors (or, in the case of an entity that is not a
corporation, for the election of the corresponding managing authority).
Notwithstanding the foregoing, neither Introgen nor Gendux shall be deemed to be
an Affiliate of the other for purposes of this Agreement.

          1.2  "Agreement Subject Matter" shall mean collectively, the Subject
Genes (as defined in the Target Gene License Agreement) and the Licensed
Technology (as defined in the Delivery Technology License Agreement).

          1.3  "Claim" shall have the meaning set forth in Section 7.1 hereof.

          1.4  "Confidential Information" shall have the meaning set forth in
 Section 5 hereof.

                                       1
<PAGE>   2

          1.5  "Development Plan and Budget" shall mean the plan and budget for
the R&D Program in effect from time to time, as established in accordance with
Section 2 hereof.

          1.6  "Delivery Technology License Agreement" shall mean that certain
Delivery Technology License Agreement of even date herewith between Introgen and
Gendux, as amended, modified or supplemented from time to time.

          1.7  "Field" shall mean [*].

          1.8  "First Financing" shall mean the closing of the sale and/or
issuance of equity and/or debt securities by Gendux, as a result of which the
cumulative total of cash proceeds from such financings received by Gendux
exceeds [*].

          1.9  "GAAP" shall mean generally accepted accounting principles in the
United States.

          1.10 "Gendux Indemnitees" shall have the meaning set forth in Section
7.1 hereof.

          1.11 "Inventions" shall mean any and all discoveries, compositions of
matter and other inventions (whether patentable or not) conceived, reduced to
practice or otherwise made in connection with the R&D Program, and all
intellectual property rights therein.

          1.12 "Management Fee" shall, for any period, have the meaning set
forth in Section 3.4 hereof.

          1.13 "R&D Costs" shall mean all direct or indirect costs, fees and
out-of-pocket or other expenses incurred, paid or accrued by Introgen in
connection with the R&D Program, determined in accordance with Section 2.1.3
hereof, and excluding any such costs, fees or expenses paid by Gendux to
Introgen under the Services Agreement.

          1.14 "R&D Personnel" shall mean employees of Introgen assigned (full-
or part-time) to perform research, development or regulatory affairs activities
under the R&D Program, including project managers, scientists, clinical research
and manufacturing staff, post-doctoral fellows, quality control and assurance
personnel, technicians or the like. As used in this Agreement, a "full-time
equivalent" or "FTE" shall mean a full-time person, or in the case of less than
a full-time dedicated person, a full-time, equivalent person year, based upon a
total of one thousand eight hundred eighty (1,880) hours per year, of work
related to the R&D Program. For purposes of the foregoing, "employees" shall
include "contract workers" who work at Introgen's facilities under Introgen's
direction, but do not include outside consultants, such as regulatory affairs
consultants, academic collaborators or the like.

          1.15 "R&D Program" shall have the meaning set forth in Section 2.1
hereof.

         [*]    Certain information on this page has been omitted and filed
                separately with the Commission. Confidential treatment has been
                requested with respect to the omitted portions.

                                       2
<PAGE>   3

          1.16 "Research Committee" shall have the meaning set forth in Section
2.1 hereof.

          1.17 "Services Agreement" shall mean that certain Administrative
Services and Management Agreement of even date herewith between Introgen and
Gendux, as amended, modified or supplemented from time to time.

          1.18 "Target Gene License Agreement" shall mean that certain Target
Gene License Agreement of even date herewith between Introgen and Gendux, as
amended, modified or supplemented from time to time.

          1.19 "Target Gene Therapy Product" shall mean any product, composition
or material the development, manufacture, use or sale of which incorporates,
utilizes, is derived from, or is otherwise based upon the Licensed Technology
and/or the Subject Genes.

     Section 2. R&D Program.

          2.1  R&D Program Services. Gendux hereby engages Introgen, and
Introgen hereby agrees to undertake, a program for the research and development
of the Agreement Subject Matter for the purpose of allowing Gendux to develop
and market within the Field one or more of the Target Gene Therapy Products (the
"R&D Program"). It is understood that portions of the preclinical research
within the Field may be conducted in the form of sponsored research programs at
academic institutions in Europe and/or at other locations, contractors or
collaborators, and that in such event Introgen shall manage such sponsored
research programs as part of the R&D Program.

               2.1.1 Research Committee. Gendux and Introgen shall establish a
research committee to oversee, review and coordinate the research and
development of Target Gene Therapy Products for applications within the Field
pursuant to the R&D Program (the "Research Committee"). The Research Committee
shall be comprised of an equal number of representatives selected by each of
Gendux and Introgen, respectively. The exact number of such representatives
shall be two (2) for each of Gendux and Introgen, or such other number as the
parties may agree. Subject to the foregoing provisions of this Section 2.1.1,
Introgen and Gendux may replace its respective Research Committee
representatives at any time, with prior written notice to the other party.
During the term of this Agreement, the Research Committee shall meet no fewer
than two (2) times each calendar year, or as otherwise agreed by the parties, at
such locations as the parties agree, and thereafter as the parties agree.
Decisions of the Research Committee shall be made by unanimous agreement of the
members present in person or by other means (e.g., teleconference) at any
meeting; provided that at least one (1) representative of each party is present
at such meeting. In the event that the Research Committee is unable to reach
unanimous approval of an issue that is expressly stated in another Section of
this Agreement to be decided by the Research Committee, the issue may be
approved by a three-fourths (3/4) vote of the Board of Directors of Gendux
(i.e., by the approval of three-fourths of the total number of Gendux Directors
then in office), which shall be deemed the approval of the Research Committee.

               2.1.2 Development Plan and Budget. Prior to the First Financing,
the parties shall mutually agree upon a reasonably detailed Development Plan and
Budget for the R&D Program outlining the objectives, activities, timing and
projected R&D Costs of the R&D Program

                                       3
<PAGE>   4

to be performed during the period beginning on the Effective Date and ending on
December 31, 2001.

               (a)  Beginning September 1, 2001 and by September 1 of each year
thereafter during the term of this Agreement, Introgen shall submit to the
Research Committee a proposed Development Plan and Budget, setting forth the
objectives, activities, timing and projected costs of the R&D Program to be
performed in the following calendar year. The Research Committee shall review
such proposals as soon as possible and shall approve the Development Plan and
Budget for the next succeeding year (i.e., in accordance with the Section 2.1.1
above, including escalation to the Gendux Board of Directors), with such changes
as the Research Committee and Introgen may agree to the plan and budget proposed
by Introgen, no later than December 15 of such year.

               (b)  Periodic Reviews. Introgen and Gendux may make changes in
the Development Plan and Budget from time to time as approved in writing by an
authorized representative of each party.

               2.1.3 R&D Costs.

               (a)  FTEs. An FTE rate determined in accordance with this Section
2.1.3 shall be used for purposes of determining the R&D Costs incurred with
respect to R&D Personnel; provided, however, that in the event such FTE rate
does not accurately reflect Introgen's actual costs associated with the R&D
Program, Introgen may, at its option, determine such R&D Costs in accordance
with GAAP and provide Gendux with a written description of such determination.
The FTE rate shall be [*]) (as adjusted below). The FTE rate includes all
salary, employee benefits, materials and other expenses including support staff
and overhead for or associated with an FTE, but does not include travel and
lodging expenses incurred by such FTEs in performance of the R&D Program (which
travel and lodging expenses shall be included in R&D Costs separately under
Section 2.1.3(b) below). Effective beginning with the calendar year 2001, the
FTE rate shall increase no more than once annually by the greater of the
percentage increase, if any, in (1) the Radford Associates Annual Biotechnology
Compensation and Benefits Survey (for the smallest geographic region that
includes Houston, Texas) or (2) the Consumer Price Index, in either case since
the Effective Date, or the last such increase, whichever is later, upon thirty
(30) days prior written notice to Gendux and such increase shall be effective
for the then-current and all subsequent Development Plans and Budgets hereunder
until further modified under this Section 2.1.3.

               (b)  Non-FTE Costs. It is understood that the R&D Costs will
include out-of-pocket costs incurred by Introgen for items other than FTEs,
including without limitation amounts paid to consultants or for sponsored
research or the like. In addition, R&D Costs may include costs for equipment and
facilities acquired for purposes of the R&D Program; provided that if such
equipment or facilities are used both (i) in the course of performing the R&D
Program and (ii) for other purposes by Introgen, then the costs of such
equipment or facilities shall be allocated between the R&D Program and such
other purposes in accordance with generally accepted accounting principles. It
is understood that if Introgen acquires any capital equipment or facilities in
connection with the R&D Program, whether or not separately identified in the
Development Plan and Budget, Introgen shall own all such capital equipment and
facilities, unless the parties otherwise agree.

         [*]    Certain information on this page has been omitted and filed
                separately with the Commission. Confidential treatment has been
                requested with respect to the omitted portions.

                                       4
<PAGE>   5

               2.1.4 Other Activities; Subcontracts. It is understood and agreed
by Gendux that Introgen shall have the right to engage in its own research and
development activities and in other business activities with other persons, and
Gendux shall not, by virtue of this Agreement have any right, title or interest
in or to such independent activities or to the income or profits derived
therefrom and, nothing set forth in this Agreement shall limit or reduce the
ability of Introgen to carry on such other activities. Gendux acknowledges and
agrees that, in performing the R&D Program Introgen may and is hereby authorized
to, without the prior consent of Gendux, engage or agree or otherwise
collaborate with other persons, including without limitation Affiliates of
Introgen or research institutions performing other research and development
activities for Introgen, to provide assistance in carrying out the R&D Program.

               2.1.5 Reports and Records. Introgen shall provide to Gendux with
periodic reports, as reasonably requested by Gendux (but no more frequently than
one each calendar quarter), summarizing (a) the work performed hereunder by
Introgen and its R&D Personnel during such quarter and (b) any material
developments with respect to the Target Gene Therapy Products during such
quarter. Introgen shall prepare a final report within ninety (90) days after the
expiration or termination of this Agreement setting forth in reasonable detail a
summary of the work performed hereunder and the material developments with
respect thereto.

          2.2  Disclaimer of Warranties. Introgen cannot and does not guarantee
that the R&D Program will be successful in whole or in part. The failure of
Introgen to develop successfully any Target Gene Therapy Product will not in and
of itself constitute a breach by Introgen of any representation, warranty,
covenant or other obligation under this Agreement, the Delivery Technology
License Agreement or the Target Gene License Agreement.

          2.3  Ownership of Inventions. Title to all Inventions made solely by
R&D Personnel in connection with the R&D Program (collectively, "R&D
Inventions") shall (as between Introgen and Gendux) be owned by Introgen. Title
to all Inventions made jointly by R&D Personnel and Gendux personnel in
connection with the R&D Program (collectively, "Joint Inventions") shall be
jointly owned by Gendux and Introgen. Except as expressly provided in this
Agreement, it is understood that neither party shall have any obligation to
account to the other for profits, or to obtain any approval of the other party
to license or exploit a Joint Invention, by reason of joint ownership of any
Joint Invention, and each party hereby waives any such right it may have under
applicable laws in any country. All matters relating to patent applications with
respect to Inventions shall be governed by Section 7.4 of the Delivery
Technology License Agreement.

          2.4  Division of Responsibility. It is understood and agreed that all
preclinical research and preclinical development activities to be conducted with
respect to Agreement Subject Matter and Target Gene Therapy Products within the
Field shall be conducted only by Introgen pursuant to the R&D Program, but that
Introgen and Gendux may otherwise allocate responsibility for clinical
development of the Target Gene Therapy Products as they may agree from time to
time. Accordingly, during the term of this Agreement, Gendux agrees not to
conduct or cooperate with any third party to conduct, any such preclinical
research or preclinical development activities outside of the R&D Program. The
foregoing shall not be deemed to restrict the activities of Introgen with
respect to research and/or development activities directed to subject matter
that may be used outside the Field.

                                       5
<PAGE>   6

     Section 3. Payment for Services; Timing of Payments.

          3.1  Payments. In consideration of the activities to be carried out by
Introgen hereunder, Gendux shall reimburse Introgen for all of its [*], as set
forth below.

          3.2  Timing of Payments. Gendux shall pay to Introgen [*], all [*]
budgeted for such calendar quarter. [*] Introgen shall deliver a statement to
Gendux for the [*] actually incurred in such calendar quarter, and Gendux shall
pay to Introgen [*] after receipt of such statement any additional [*] in excess
of Gendux's actual payments to Introgen hereunder during such calendar quarter,
subject to Section 3.3 below. If the amount reflected in the quarterly statement
for [*] is less than the [*] actually paid by Gendux to Introgen in such
calendar quarter, Introgen shall apply such excess against the [*] incurred in
the succeeding calendar quarters.

          3.3  Excess Costs. To the extent the [*] incurred in a calendar
year exceed by more than [*] the [*] budgeted for such calendar year in the
Development Plan and Budget then in effect, Gendux shall not be responsible to
reimburse any portion of such excess [*] unless it approves such excess [*],
which approval shall not be unreasonably withheld or delayed; likewise, unless
otherwise mutually agreed by the parties, Introgen shall not be obligated to
incur [*] in excess of the amounts set forth in the then-current Development
Plan and Budget.

          3.4  Management Fee. In addition to the [*] to be reimbursed as
set forth above, Gendux agrees to pay to Introgen a management fee equal to [*]
of such [*] (the "Management Fee"). Each payment of [*] pursuant to Section 3.2
above shall include with it the corresponding Management Fee (i.e., an
additional payment equal to [*] of such [*]).

     Section 4. Representations, Warranties and Covenants.

          4.1  Representations, Warranties and Covenants of Introgen. Introgen
represents, warrants and covenants to Gendux as follows:

               (a)  Introgen is a corporation duly organized validly existing
and in good standing under the laws of the state of Delaware with corporate
powers adequate for executing and delivering, and performing its obligations
under, this Agreement;

               (b)  the execution, delivery and performance of this Agreement
have been duly authorized by all necessary corporate action on the part of
Introgen;

               (c)  this Agreement has been duly executed and delivered by
Introgen and is a legal, valid and binding obligation of Introgen, enforceable
against Introgen in accordance with its terms;

         [*]    Certain information on this page has been omitted and filed
                separately with the Commission. Confidential treatment has been
                requested with respect to the omitted portions.

                                       6
<PAGE>   7

               (d)  the execution, delivery and performance of this Agreement do
not and will not conflict with or contravene any provision of the charter
documents or by-laws of Introgen or any agreement, document, instrument,
indenture or other obligation of Introgen;

               (e)  the R&D Plan was prepared in good faith by Introgen, based
upon information and assumptions that Introgen believes to be reasonable and
correct and, as of the Effective Date, Introgen is not aware of any discovery,
change or development concerning any of the Target Gene Therapy Products having
a material adverse effect upon the accuracy or appropriateness of information or
assumptions contained in the R&D Plan; and

               (f)  the representations and warranties of Introgen under Section
10.1 of the Delivery Technology License Agreement and Section 10.1 of the Target
Gene License Agreement are true and correct as of the Effective Date.

     4.2 Representations, Warranties and Covenants of Gendux. Gendux represents,
warrants and covenants to Introgen as follows:

               (a)  Gendux is a corporation duly organized validly existing and
in good standing under the laws of Delaware with corporate powers adequate for
executing and delivering, and performing its obligations under, this Agreement;

               (b)  the execution, delivery and performance of this Agreement
have been duly authorized by all necessary corporate action on the part of
Gendux;

               (c)  this Agreement has been duly executed and delivered by
Gendux and is a legal, valid and binding obligation of Gendux, enforceable
against Gendux in accordance with its terms;

               (d)  the execution, delivery and performance of this Agreement do
not and will not conflict with or contravene any provision of the charter
documents or by-laws of Gendux or any agreement, document, instrument, indenture
or other obligation of Gendux;

               (e)  the representations and warranties of Gendux under Section
10.2 of the Delivery Technology License Agreement and Section 10.2 of the Target
Gene License Agreement are true and correct as of the Effective Date; and

               (f)  Gendux shall not, during the term of this Agreement without
the prior written consent of Introgen, solicit the employment of, or employ any
person, in any capacity who, at any time during the term of this Agreement,
shall have been an officer, director, employee or agent of Introgen.

     Section 5. Confidentiality. Confidentiality of information disclosed
between Introgen and Gendux shall be governed by Section 11 of the Delivery
Technology License Agreement.

                                       7
<PAGE>   8

     Section 6. Disclaimer of Warranty.

               EXCEPT AS OTHERWISE EXPLICITLY PROVIDED IN SECTION 4.1, INTROGEN
EXPRESSLY DISCLAIMS ANY WARRANTIES OR CONDITIONS, EXPRESS, IMPLIED, STATUTORY OR
OTHERWISE, WITH RESPECT TO THE R&D PROGRAM OR THE AGREEMENT SUBJECT MATTER,
INCLUDING, WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE, VALIDITY OF THE AGREEMENT SUBJECT MATTER, PATENTED OR
UNPATENTED, AND NONINFRINGEMENT OF THE INTELLECTUAL PROPERTY RIGHTS OF THIRD
PARTIES.

     Section 7. Indemnification and Insurance.

          7.1  Gendux Right to Indemnification. Introgen shall indemnify each of
Gendux, its successors and assigns, and the directors, officers, employees,
agents and counsel thereof (the "Gendux Indemnitees"), pay on demand and
protect, defend, save and hold each Gendux Indemnitee harmless from and against,
on an after-tax basis, any and all liabilities, damages, losses, settlements,
claims, actions, suits, penalties, fines, costs or expenses (including, without
limitation, reasonable attorneys' fees) (any of the foregoing, a "Claim")
asserted by a third party against any Gendux Indemnitee of whatever kind or
nature, including, without limitation, any claim or liability based upon
negligence, warranty, strict liability, violation of government regulation or
infringement of patent or other proprietary rights, arising from or occurring as
a result of (a) any use of the Agreement Subject Matter by Introgen or its
Affiliates or sublicensees (other than Gendux outside this Agreement), (b) any
of the activities or services to be performed by Introgen hereunder or (c) any
breach by Introgen of this Agreement, except in all cases claims based upon the
willful misconduct of Gendux. Gendux shall promptly notify Introgen of any
Claim, upon becoming aware thereof, and permit Introgen at Introgen's cost to
defend against such Claim and shall cooperate in the defense thereof. Neither
Gendux nor Introgen shall enter into, or permit, any settlement of any such
Claim without the express written consent of the other party. Gendux may, at its
option and expense, have its own counsel participate in any proceeding which is
under the direction of Introgen and will cooperate with Introgen and its insurer
in the disposition of any such matter.

          7.2  Insurance. Introgen shall, to the extent available at
commercially reasonable rates, maintain, with insurers or underwriters of good
repute, such insurance relating to the R&D Program as is customary for
comparable businesses undertaking research programs of a similar nature, to
maintain against such risks and pursuant to such terms (including deductible
limits or self-insured retentions) as are customary and reasonable for such
businesses.

     Section 8. Term and Termination.

          8.1  Term. This Agreement shall be effective as of the Effective Date
and shall continue in full force and effect during the term of the R&D Program,
unless earlier terminated as provided in Sections 8.2 and 8.3 hereof. For such
purposes, the "term of the R&D Program" shall continue until the later of (i)
December 31, 2001 or (ii) the end of the last period for which a Development
Plan and Budget has been established in accordance with Section 2.1.2 above. If
for any period after 2001, a Development Plan and Budget has not been
established for a period of one

                                       8
<PAGE>   9

hundred twenty (120) days, then either party shall have the right to terminate
the term of R&D Program upon written notice to the other party.

          8.2  Termination for Breach. Either Gendux or Introgen may terminate
this Agreement, in the event the other shall have materially breached or
defaulted in the performance of any of its obligations hereunder and such breach
shall have continued for thirty (30) days after written notice is given by the
nonbreaching party to the breaching party specifying the breach. For such
purposes, a breach of the Target Gene License Agreement, the Delivery Technology
License Agreement or the Services Agreement shall be deemed a breach of this
Agreement.

          8.3 Termination upon Notice. Either Gendux or Introgen may terminate
this Agreement at anytime, for any reason or for no reason, by giving the other
party one hundred eighty (180) days prior written notice thereof.

          8.4 Effect of Termination. Sections 1, 2.2, 2.3, 5, 6, 7, 8.4 and 9 of
this Agreement, and all obligations to pay any amounts due hereunder, shall
survive, and shall not be affected by, any termination or expiration of this
Agreement.

     Section 9. General.

          9.1  Independent Contractors. The relationship of Gendux and Introgen
established by this Agreement is that of independent contractors. Nothing in
this Agreement shall be construed to create any other relationship between the
parties. Neither party shall have any express or implied right, power or
authority to assume, create or incur any expense, liability or obligation on
behalf of or in the name of the other party.

          9.2  Confidential Terms. Except as expressly provided herein, each
party agrees not to disclose any terms of this Agreement to any third party
without the prior written consent of the other party, except as required by
securities or other applicable laws and (subject to reasonable conditions of
confidentiality) to prospective and other investors and such party's
accountants, attorneys and other professional advisors.

          9.3  Assignment. This Agreement shall not be assignable by either
party to any third party without the prior written consent of the other party
hereto, except that either party may assign this Agreement without the other
party's consent to an entity that acquires all or substantially all of the
business or assets of the assigning party, in each case whether by sale, merger,
transfer of assets, operation of law or otherwise; provided that in either case,
such assignee or transferee promptly agrees in writing to be bound by the terms
and conditions of this Agreement. Without limiting the foregoing, in the event
of such merger or transfer or acquisition of assets, no intellectual property
rights of the assignee or its affiliate shall be included in the Agreement
Subject Matter, to the extent that such intellectual property rights were owned
or controlled by the assignee or its affiliate prior to such merger or transfer
or acquisition of assets, or are created outside the R&D Program by personnel
who were not employees of the assigning party prior to the merger or transfer or
acquisition of assets. Upon a permitted assignment of this Agreement, all
references herein to the assigning party shall be deemed references to the
assignee. Any assignment not permitted under this Section 9.3 shall be null and
void.

                                       9
<PAGE>   10

          9.4  Force Majeure. Nonperformance of either party (except for payment
of amounts due hereunder) shall be excused to the extent that performance is
rendered impossible by strike, fire, earthquake, flood, governmental acts or
orders or restrictions, or any other reason, including failure of suppliers,
where failure to perform is beyond the reasonable control of the nonperforming
party. Without limiting the foregoing, the party subject to such inability shall
use reasonable efforts to minimize the duration of any force majeure event.

          9.5  Notices. All notices, requests and other communications hereunder
shall be made in writing and shall be sent by registered or certified mail,
return receipt requested, postage prepaid; facsimile transmission (receipt
verified); or express courier service (signature required), in each case to the
respective address or fax number specified below, or such other address or fax
number as may be specified in writing to the other party:

                  Gendux:                   Gendux, Inc.
                                            301 Congress Avenue, Suite 1850
                                            Austin, Texas 78701
                                            Attn:  President
                                            Fax:  (512) 708-9311

                  with a copy to:           Wilson Sonsini Goodrich & Rosati
                                            650 Page Mill Road
                                            Palo Alto, California 94304-1050
                                            Attn:  Kenneth A. Clark, Esq.
                                            Fax:  (650) 493-6811

                  Introgen:                 Introgen Therapeutics, Inc.
                                            301 Congress Avenue, Suite 1850
                                            Austin, Texas 78701
                                            Attn:  President
                                            Fax:  (512) 708-9311

                  with a copy to:           Wilson Sonsini Goodrich & Rosati
                                            650 Page Mill Road
                                            Palo Alto, California 94304-1050
                                            Attn:  Kenneth A. Clark, Esq.
                                            Fax:  (650) 493-6811

          9.6  Governing Law. This Agreement shall be governed by, and construed
and interpreted in accordance with, the laws of the State of Texas, without
regard to conflicts of laws principles. Exclusive venue and jurisdiction of any
disputes governed by this Agreement shall be in the federal courts for the State
of Texas. The parties hereby consent to the jurisdiction of such courts.

          9.7  Compliance with Law. Gendux shall comply with all applicable laws
and regulations in connection with its activities pursuant to this Agreement.

                                       10
<PAGE>   11

          9.8  Modification; Waiver. No amendment or modification of any
provision of this Agreement shall be effective unless in writing signed by the
party to be charged. No provision of this Agreement shall be varied,
contradicted or explained by any oral agreement, course of dealing or
performance, or any other matter not set forth in an agreement in writing and
signed by both parties hereto. No failure on the part of either party to
exercise, and no delay in exercising any right under this Agreement or provided
by statute or at law or in equity or otherwise, shall impair, prejudice or
constitute a waiver of any such right, nor shall any partial exercise of any
such right preclude any other or further exercise thereof or the exercise of any
other right.

          9.9  Headings. Headings included herein are for convenience only, do
not form a part of this Agreement and shall not be used in any way to construe
or interpret this Agreement.

          9.10 Severability. If any provision hereof should be held invalid,
illegal or unenforceable in any jurisdiction, the parties shall negotiate in
good faith a valid, legal and enforceable substitute provision that most nearly
reflects the original intent of the parties (or shall strike such provision in
the absence of such substitute provision) and all other provisions hereof shall
remain in full force and effect in such jurisdiction and shall be liberally
construed in order to carry out the intentions of the parties hereto as nearly
as may be possible. Such invalidity, illegality or unenforceability shall not
affect the validity, legality or enforceability of such provision in any other
jurisdiction.

          9.11 Entire Agreement. This Agreement (including the Exhibit hereto)
together with the Target Gene License Agreement, the Delivery Technology License
Agreement and the Services Agreement (including the respective Exhibits
thereto), each entered into by the parties of even date, constitute the entire
understanding and agreement between the parties with respect to the subject
matter hereof and supersede any and all prior negotiations, representations,
agreements, and understandings, whether written or oral, between the parties
with respect to such subject matter.

          9.12 Counterparts. This Agreement may be executed in two counterparts,
each of which shall be deemed an original, but both of which together shall
constitute one and the same instrument.

            (The remainder of this page is intentionally left blank.)

                                       11
<PAGE>   12

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed and delivered as of the date first above written.

INTROGEN THERAPEUTICS, INC.

By   /s/ JAMES W. ALBRECHT, JR.
   ------------------------------
Its  Chief Financial Officer
   ------------------------------

GENDUX, INC.

By   /s/ DAVID G. NANCE
   ------------------------------

Its  President & CEO
   ------------------------------

                                       12

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