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                                                                 EXHIBIT 10.15

                                LICENSE AGREEMENT


         This License Agreement ("Agreement") is made as of March 29, 1996 (the
"Effective Date") by and between the Sidney Kimmel Cancer Center ("SKCC") and
Introgen Therapeutics, Inc. ("Licensee"), a corporation duly organized and
existing under the laws of Delaware.


                                R E C I T A L S:

         A. SKCC owns certain Patent Rights and Related Technology (as defined
below).

         B. Licensee and SKCC have entered into a Research Agreement of even
date herewith, pursuant to which Licensee has agreed to fund certain research
conducted by SKCC (the "Research Agreement").

         C. Licensee wishes to obtain a license from SKCC to the Patent Rights
and Related Technology, and other subject matter resulting from research
conducted pursuant the Research Agreement, all on the terms and conditions set
forth below.

         NOW, THEREFORE, in consideration of the mutual covenants and premises
herein contained, the parties hereto agree as follows:


                                    ARTICLE 1

                                   DEFINITIONS

         As used in this Agreement, the following terms shall have the meanings
indicated:

         1.1 "Licensed Product" shall mean any product, the manufacture, use or
sale of which would infringe a Valid Claim.

         1.2 "Licensed Subject Matter" shall mean inventions, discoveries and
other subject matter covered by Patent Rights or within the Related Technology.

         1.3 "Net Sales" shall mean the gross revenues actually received by
Licensee, its Affiliates and Sublicensees from sales of a Licensed Product,
which sales would, but for the license granted hereunder, infringe a Valid Claim
in the country for which the Licensed Product is made or sold, less (a) normal
and customary rebates, cash and trade discounts or the like actually given, (b)
sales, use and/or other taxes or duties actually paid, (c) outbound shipping and
insurance charges actually paid, (d) import and/or export duties actually paid,
and (e) amounts credited due to actual returns.

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\         1.4      "Patent Rights" shall mean any and all rights in and to:

                  (a) the patent applications listed in Exhibit A ("Existing
         Applications"), any foreign counterparts of such Existing Applications
         and any patent or application anywhere in the world that is owned or
         controlled by SKCC to the extent such patent or application claims and
         discloses subject matter which could have been claimed in the Existing
         Applications.

                  (b) any patent or patent application of any kind anywhere in
         the world that is owned or controlled by SKCC that claims and discloses
         any invention that is conceived (and evidenced in writing) or reduced
         to practice by [*], which inventions are made in the course of
         performing the Research Program during the term of the Research
         Agreement (as the Research Program is defined in Section 1.1 of the
         Research Agreement). It is understood that the Research Program shall
         not include subject matter to the extent such subject matter consists
         of [*] licensed or assigned to [*] under certain License and Sponsored
         Research Agreements [*] as amended prior to the Effective Date. [*].

                  (c) all divisions, continuations, substitutions,
         registrations, reissues, reexaminations or extensions of any kind with
         respect to any of the foregoing.

                  (d) continuations-in-part of any of the foregoing applications
         and patents issuing on such continuations-in-part, patents of addition,
         and all reissues, renewals and extensions of such patents and patents
         of addition, shall also be within the Patent Rights, but only to the
         extent the same claim and disclose subject matter that could have been
         claimed in the patents or applications described in (a), (b) or (c)
         above. Accordingly, it is understood that new subject matter that could
         not have been claimed in the patents or applications described in (a),
         (b) or (c) above shall not be within the Patent Rights.

In the event that SKCC is a joint owner of an invention by reason of the fact
that an employee or consultant of Licensee is a joint inventor of such an
invention, it is understood that the Patent Rights include only SKCC's rights as
a joint owner of the patents and patent applications that claim such joint
invention. In addition, the Patent Rights shall not include patents or
applications described in 1.4(b) above, to the extent [*] are not required to
assign the same to SKCC; nor shall the Patent Rights be deemed to include any
patent or application owned by Licensee, or licensed to Licensee by a third
party. From time to time during the term of this Agreement, upon request by
either party, Licensee and Sponsor shall promptly update Exhibit A hereto to
include all patent applications and patents that are within the Patent Rights.

         1.5 "Research Program" shall mean the Research Program conducted by
SKCC personnel pursuant to the Research Agreement.

         1.6 "Affiliate" shall mean any corporation or other entity that is
directly or indirectly controlling, controlled by or under common control with
Licensee. For the purpose of this definition, "control" shall mean the direct or
indirect ownership of more than fifty percent (50%) of the shares of

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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).

         1.7 "Related Technology" shall mean any and all technical information,
know-how, process, procedure, composition, device, method, formula, protocol,
technique, design, drawing, data or other subject matter owned or controlled by
SKCC directly made in the course of performing the Research Program.

         1.8 "Sublicensee" shall mean a third party to whom Licensee has granted
the right to manufacture and sell Licensed Products, with respect to Licensed
Products made and sold by such third party.

         1.9 "Valid Claim" shall mean (a) a claim of an issued and unexpired
patent included within the Patent Rights, which has not been held unenforceable,
unpatentable or invalid by a court or other governmental agency of competent
jurisdiction, and (b) a pending claim of a patent application included within
the Patent Rights for [*] from the first date from which such application takes
priority for filing purposes. In the event that a claim of an issued and
unexpired patent within the Patent Rights is held by a court or other
governmental agency of competent jurisdiction to be unenforceable, unpatentable
or invalid, and such holding is reversed on appeal by a higher court or agency
of competition jurisdiction, such claim shall be reinstated thereafter as a
Valid Claim hereunder.


                                    ARTICLE 2

                         REPRESENTATIONS AND WARRANTIES

         2.1 Warranties. SKCC represents and warrants that (a) SKCC is and shall
be the owner of the entire right, title, and interest in and to the Patent
Rights; (b) SKCC has the sole right and authority to enter into this Agreement
and grant the rights and licenses hereunder; (c) SKCC has not previously granted
and will not grant any rights in the Licensed Subject Matter that are
inconsistent with the rights and licenses granted to Licensee or contemplated
herein; (d) SKCC has obtained written agreements from all personnel associated
with SKCC who will perform work in connection with the Research Program, which
agreements assign to SKCC all patent rights in any invention conceived or
reduced to practice by such personnel in the course of performing research at
SKCC. SKCC makes no representations or warranties as to the (i) validity or
scope of the Patent Rights, or (ii) except as provided below, freedom of
Licensed Products from infringement of third party proprietary rights. SKCC
assumes no obligation to bring or prosecute actions against third parties for
patent infringement.

         2.2 Representation to Knowledge. In addition, SKCC represents that to
the best knowledge of [*] and the technology transfer office at SKCC, as of the
Effective Date: (a) exercise of the license granted hereunder will not infringe
the rights of any third party to any patent, patent


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application, invention or any other proprietary right; provided that no
representation is made with respect to any patents (i) of which Dr. Jack Roth is
an inventor, or (ii) listed on Exhibit D attached hereto or claiming subject
matter described in the publications listed on Exhibit D; (b) SKCC does not own
or control rights to any patent, patent application or invention that relates to
the subject matter of the Existing Applications, or the practice of which would
be infringed by Licensee's exercise of the license granted hereunder; and (c)
except for the Existing Applications, the applications listed on Exhibit B
hereto and the inventions disclosed therein, SKCC does not own or control rights
to any patent, patent application or invention pertaining to gene or cell
therapy. The parties acknowledge and agree that any representations made in this
Section 2.2 are made with respect to the best knowledge of [*] and the
technology transfer office at SKCC as of the Effective Date and not with respect
to any knowledge of the foregoing parties acquired after the Effective Date. As
to subsection (a) above, it is understood among the parties that SKCC has not
conducted a patent search with respect to the Patent Rights.

         2.3 Disclaimer. EXCEPT AS PROVIDED IN THIS ARTICLE 2, NEITHER PARTY
MAKES ANY REPRESENTATIONS OR WARRANTIES OTHER THAN THOSE EXPRESSLY STATED IN
THIS AGREEMENT, AND SPECIFICALLY, SKCC MAKES NO EXPRESS OR IMPLIED WARRANTIES OF
NONINFRINGEMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.


                                    ARTICLE 3

                                     LICENSE

         3.1      Grant.

                  (a) Patent Rights. SKCC hereby grants to Licensee a worldwide,
royalty-bearing, exclusive license under the Patent Rights to manufacture, have
manufactured, use, sell, import and export Licensed Products, to practice any
method, process or procedure claimed in the Patent Rights, and to otherwise
exploit the Patent Rights.

                  (b) Related Technology. SKCC also hereby grants to Licensee a
worldwide nonexclusive license under the Related Technology to manufacture, have
manufactured, use, sell, import and export Licensed Products and to otherwise
exploit the Related Technology. It is understood that this Section 3.1(b) shall
not be deemed to limit Introgen's rights under Section 3.1(a) above.

         3.2 Sublicenses. Licensee may grant and authorize sublicenses within
the scope of the licenses granted to Licensee pursuant to this Agreement.
Licensee shall include or reference in all sublicense agreements at a minimum
terms and conditions substantially similar to those listed in Exhibit C attached
hereto. Licensee shall promptly inform SKCC of each such sublicense.


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         3.3 Reservation of Rights. The licenses granted in this Article 3 are
subject to a reserved nonexclusive license in SKCC to use the Patent Rights
solely for its own educational and non- commercial research purposes.


                                    ARTICLE 4

                              PAYMENTS AND REPORTS

         4.1 Patent Expenses. Within thirty (30) days after execution of this
Agreement, Introgen shall reimburse SKCC for the documented expenses paid by
SKCC prior to the Effective Date to outside patent counsel and government patent
offices with respect to the preparation, filing and prosecution of the Existing
Applications; provided that such amounts to be reimbursed shall not exceed [*].

         4.2 Base Royalty. In consideration of the rights and licenses granted
by SKCC to Licensee under this Agreement, except as otherwise provided in this
Article 4, Licensee agrees to pay to SKCC as running royalties the following
percentage of Net Sales from Licensed Products sold by Licensee, its Affiliates
and Sublicensees:

                  (a) Subject to paragraph (b) below, the following percentage
         of cumulative Net Sales of all Licensed Products:

                           [*] of the first [*] in cumulative Net Sales
                           [*] oF [*] in cumulative Net Sales
                           [*] of Net Sales over [*]

                  (b) Notwithstanding paragraph (a) above, if the Valid Claims
         that cover a Licensed Product are dominated (to the extent such Valid
         Claims cover such Licensed Product) by claims of an issued patent owned
         or controlled by Licensee (other than the Patent Rights), the royalty
         on Net Sales of such Licensed Products shall be reduced to [*] of such
         Net Sales. The parties shall endeavor to mutually agree as to whether
         the particular Valid Claims are so dominated.

In the event that the only Valid Claims which cover the sale of a Licensed
Product in a particular country are claims of a patent or application with
respect to which one or more employees or contractors of Licensee or a third
party are joint inventors, the royalty rates specified above on sales of such
Licensed Product in such country shall be reduced by [*].

          4.3 Royalty Term. The running royalties under Section 4.2 shall be
payable only for sales of Licensed Products by Licensee, Affiliates or
Sublicensees in a county after the date of the first commercial sale of such
Licensed Product in the particular country until the expiration of the last to
expire of the patents within the Patent Rights.


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          4.4 Multiple Royalties. If Licensee, its Affiliate or Sublicensee is
required to pay to non- Affiliate third parties royalties with respect to a
Licensed Product under agreements entered into after the Effective Date for
patent rights or other technologies which Licensee, its Affiliate or
Sublicensee, in its reasonable judgment, determines are desirable to license or
acquire with respect to such Licensed Product, and the total of such third party
royalties and the royalties to be paid by Licensee to SKCC would exceed [*] on
sales of such Licensed Products by Licensee and/or Affiliates or [*] on sales of
such Licensed Products by Sublicensees, the amounts to be paid under Section 4.2
shall be reduced in accordance with the following formulas:

                  (a) Royalties payable on sales by Licensee and/or Affiliates
          of such Licensed Products shall equal the amount calculated in
          accordance with Section 4.2, multiplied by the fraction [*], where "X"
          equals the total percentage of Net Sales payable as royalties to SKCC
          and such third parties on such sales (prior to the adjustment
          hereunder and any similar adjustment in the amount to be paid to such
          third parties).

                  (b) Royalties payable on sales by Licensee's Sublicensees of
          such Licensed Products shall equal the amount calculated in accordance
          with Section 4.2, multiplied by the fraction [*], where "X" equals the
          total percentage of Net Sales payable as royalties to SKCC and such
          third parties on sales by Licensee's Sublicensees of Licensed Products
          (prior to the adjustment hereunder and any similar adjustment in the
          amount to be paid to such third parties).

Notwithstanding the foregoing, the reductions in (a) and (b) above shall not
reduce by more than [*] the amounts otherwise payable under this Agreement to
SKCC with respect to a Licensed Product, after taking any other adjustments
hereunder into account. It is understood the adjustment in this Section 4.4
shall not apply to increase the amounts payable under Section 4.2.

          4.5 Single Royalty; Non-Royalty Sales. In the event that more than one
patent within the Patent Rights is applicable to any Licensed Product subject to
royalties under this Article 4, then only one royalty shall be paid to SKCC in
respect of such Licensed Product. It is understood that royalties shall only be
payable under this Article 4 with respect to Licensed Products whose manufacture
or sale would infringe a Valid Claim in the country for which such Licensed
Product is made or sold. No royalty shall be payable under Section 4.2 above
with respect to sales of Licensed Products among Licensee and Affiliates for
resale; and in no event shall more than one royalty be due hereunder with
respect to any Licensed Product unit; nor shall a royalty be payable under
Section 4.2 with respect to sales of Licensed Products for use in research
and/or development, in clinical trials or as samples.

          4.6 Combination Products. In the event that a Licensed Product is sold
in combination as a single product with another product, component or service
for which no royalty would be due hereunder if sold separately, Net Sales from
such combination sales for purposes of calculating the amounts due under this
Article 4 shall be reasonably allocated between such Licensed Product and such
other product, component and/or service. Without limiting the foregoing, it is
understood and


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agreed that in no event shall Net Sales include amounts charged for surgical
procedures, hospital stays or other charges not specifically made for the sale
of Licensed Products. The parties will endeavor to mutually agree upon the
reasonable allocations described above.

          4.7 Records. Licensee shall keep complete and accurate records of its
Net Sales in sufficient detail to enable the royalties payable hereunder to be
determined. Licensee shall also keep reports of Net Sales made by its
Sublicensees and Affiliates. Upon SKCC's written request, but not more
frequently than once per calendar year, Licensee shall permit representatives or
agents of SKCC, at SKCC's expense, to examine such records during Licensee's
regular business hours for the purpose of and to the extent necessary to verify
any report required under this Agreement with respect to Net Sales received not
more than three (3) years prior to the date of SKCC's request. Notwithstanding
any of the foregoing, inspections of the records of Sublicensees shall be
limited to the extent that Licensee has the right to authorize SKCC to make such
inspection; provided that, if Licensee does not have the right to authorize SKCC
to make such an inspection, upon SKCC's request, Licensee shall exercise its own
right to inspect the Sublicensee's records at SKCC's expense (such expenses to
be approved in advance by SKCC) and shall share with SKCC the results of such
inspections. Licensee shall have the right to have its representative
participate in such inspection. In the event that the amounts due to SKCC are
determined to have been underpaid, Licensee shall pay to SKCC any amount due and
unpaid, together with interest on such amount at the prime rate in effect at
Bank of America NT&SA, San Francisco, California, or at the maximum rate
permitted by law, whichever is lower. In the event the inspection establishes an
underpayment greater than [*] for the period covered by the inspection, Licensee
agrees to pay the reasonable out-of-pocket costs of such inspection.

          4.8 Reports. Beginning with the first accrual of Net Sales on which a
royalty is due hereunder, Licensee shall provide to SKCC a [*] royalty report,
as follows: Within [*] after the end of each [*], Licensee shall deliver to SKCC
a true and accurate report, giving such particulars of the business conducted by
Licensee, Affiliates and its Sublicensees, if any, during such [*] as are
pertinent to an account for payments hereunder. Such report shall be reasonably
detailed and shall include at least (a) the total of Net Sales; (b) the
calculation of royalties; and (c) the total royalties so calculated and due
SKCC. To the extent consistent with Licensee's internal reporting procedures,
Licensee shall make good faith efforts to reflect in its reports hereunder Net
Sales on a product-by-product and country-by-country or territory-by-territory
basis. Simultaneously with the delivery of each such report, Licensee shall pay
to SKCC the total royalties, if any, due to SKCC for the period of such report.
If no royalties are due, Licensee shall so report. SKCC shall not provide to
third parties any information contained in reports provided to Licensee
hereunder, or learned by SKCC under Section 4.7 above; provided that SKCC may
have such reports reviewed by its accountants and legal advisors. Licensee
agrees to forward to SKCC, on an annual basis, a copy of all reports of Net
Sales received by Licensee from its Sublicensees during the preceding twelve
(12) month period as shall be pertinent to a royalty accounting under said
sublicense agreements. Such reports may be redacted to omit any information not
necessary to determine Net Sales or amounts due to SKCC hereunder.


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          4.9 Payments. All amounts payable hereunder by Licensee shall be
payable in United States Dollars. If any currency conversion shall be required
in connection with the payment of royalties hereunder, such conversion shall be
made by using the exchange rates used by Licensee in calculating Licensee's own
revenues for financial reporting purposes. Any withholding or other tax that
Licensee or any of its Affiliates are required by law to withhold and pay on
behalf of SKCC shall be deducted from said royalties and promptly paid to the
taxing authority.

          4.10 Conversion. Effective upon [*], Licensee may convert the license
granted to Licensee under Section 3.1(a) to a [*]; provided, however, Licensee
may not convert the license as provided under this Section 4.10 with respect to
[*]. In the event of conversion, the amounts to be paid to SKCC under this
Article 4 following the effective date of such notice after any adjustment shall
be [*], to the extent such payments are made with respect to Valid Claims within
such patent for which the license is so converted.


                                    ARTICLE 5

                              TERM AND TERMINATION

          5.1 Term. Unless terminated earlier pursuant to this Article 5, the
term of this Agreement shall commence on the Effective Date and continue in full
force and effect until expiration, revocation or invalidation of the last patent
or the abandonment of the last application within the Patent Rights, whichever
is later. Licensee's license with respect to the Related Technology shall
survive this Agreement except upon a termination by SKCC under Section 5.3.2
below.

          5.2 Termination for Breach. In the event of a material breach of this
Agreement (including a material breach of warranty), the nonbreaching party
shall be entitled to terminate this Agreement by written notice to the breaching
party, if such breach is not cured within [*] after written notice is given by
the nonbreaching party to the breaching party specifying the breach. However, if
the party alleged to be in breach of this Agreement disputes such breach within
such [*] period, the nonbreaching party shall not have the right to terminate
this Agreement unless it has been determined pursuant to an arbitration under
Section 11.9 below that this Agreement was materially breached, and the
breaching party fails to comply with its obligations hereunder within [*] after
such determination. The right to terminate under this Section 5.2 shall be in
addition to, and not in lieu of, any other rights or remedies the nonbreaching
party may have under this Agreement, whether at law or in equity. Any
termination of this Agreement under this Section 5.2 by SKCC shall not relieve
Licensee of any obligation to pay any fees owed to SKCC nor impair any right of
SKCC that accrues prior to the effective date of such termination.

          5.3     Termination Upon Notice.

                  5.3.1 By Licensee. Licensee may terminate this Agreement, in
its entirety or as to any particular patent or application within the Patent
Rights, or as to any particular Licensed Product,


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at any time by [*]. From and after the effective date of a termination under
this Section 5.3 with respect to a particular patent or application, such
patent(s) and application(s) in the particular country shall cease to be within
the Patent Rights for all purposes of this Agreement, and all rights and
obligations of Licensee with respect to such patent(s) and application(s) shall
terminate; from and after the effective date of a termination under this Section
5.3 with respect to a particular Licensed Product, the license granted to
Licensee under Section 3.1 shall terminate with respect to such Licensed
Product. Upon a termination of this Agreement in its entirety under this Section
5.3.1, all rights and obligations of the parties shall terminate, except as
provided in Section 5.4 below; provided that following such termination,
Licensee shall pay all patent expenses and royalties for the Patent Rights,
which in each case were due hereunder and accrued prior to the effective date of
such termination.

                  5.3.2 By SKCC. SKCC may terminate this Agreement upon [*]
provided that SCKK so terminates this Agreement in such event within [*]. Upon
termination of this Agreement by SKCC under this Section 5.3.2, all of the
licenses granted to Licensee under this Agreement shall immediately terminate.

          5.4     Survival.

                  (a) 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.

                  (b) In the event this Agreement is terminated for any reason,
Licensee and its Affiliates shall have the right to sell or otherwise dispose of
the stock of any products then on hand, all subject to the payment to SKCC of
fees and royalties pursuant to Article 4 hereof. Upon termination of this
Agreement by SKCC for any reason (other than a termination by SKCC under Section
5.3.2 above), any sublicense granted by Licensee hereunder shall survive,
provided that upon request by SKCC, such Sublicensee promptly agrees in writing
to be bound by the applicable terms of this Agreement.

                  (c) Articles 1, 2.3, 4.7, 4.8, 5, 7, 8, 10 and 11 shall
survive the expiration and any termination of this Agreement. Except as
otherwise provided in this Article 5, all rights and obligations of the parties
under this Agreement shall terminate upon the expiration or termination of this
Agreement. In addition, any termination of this Agreement shall not relieve
Licensee of any payment obligations to SKCC that accrue prior to the effective
date of such termination.

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                                    ARTICLE 6

                                  INFRINGEMENT

          6.1 Enforcement. Licensee shall have the exclusive right (itself or
through others), at its sole option, to bring suit to enforce the Patent Rights.
All recoveries in such suit (whether initiated by Licensee or its designee, or
brought as a counterclaim in a suit commenced by a third party) will [*].

          6.2 Defense. If Licensee or a Sublicensee, distributor or other
customer is sued by a third party charging infringement of patent rights that
dominate a claim of the Patent Rights or that cover the development,
manufacture, use, distribution or sale of a Licensed Product, Licensee will
promptly notify SKCC. As between the parties to this Agreement, [*] will be
entitled to control the defense in any such action(s) and [*]. If Licensee is
required to pay a royalty or other amount to a third party to make and/or sell a
Licensed Product as a result of a final judgment or settlement, [*].

          6.3 Cooperation. In any suit, action or other proceeding in connection
with enforcement and/or defense of the Patent Rights, [*]. Upon the request of
and, at the expense of [*] shall make available at reasonable times and under
appropriate conditions all relevant personnel, records, papers, information,
samples, specimens and other similar materials [*]. Any such cooperation
provided by [*] shall be subject to reimbursement by [*] for reasonable
out-of-pocket expenses.


                                    ARTICLE 7

                                 INDEMNIFICATION

          Licensee shall defend, hold harmless and indemnify SKCC, its officers,
directors, employees and agents from and against amounts paid to third parties
as a result of any claims, liabilities, expenses (including reasonable
attorneys' fees), demands, or causes of action whatsoever caused by, or arising
out of, or resulting from, the exercise or practice of the rights and license
granted under this Agreement by Licensee; provided that (a) Licensee receives
prompt notice of any such claim, demand or cause of action, (b) Licensee shall
not be obligated with respect to any settlement unless Licensee consents in
writing to such settlement, and (c) Licensee shall have the exclusive right to
defend any such claim, demand or cause of action.


                                    ARTICLE 8

                                USE OF SKCC NAME

          Except as required by law or in the normal course of business
identification, neither Licensee or SKCC shall issue any press release or other
public statements in connection with this Agreement


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intended for use in the public media in a manner suggesting any endorsement by
the other of Licensee or SKCC, respectively, without the approval of such other
party, which approval shall not be unreasonably withheld.


                                    ARTICLE 9

                             PATENTS AND INVENTIONS

          9.1 Prosecution by[*]. [*] shall have the right, at its option, to
control the filing for, prosecution and maintenance of the Patent Rights. If [*]
elects not to control the filing for, prosecution and maintenance of the Patent
Rights, [*] shall have the right to do so at its expense. As used herein,
"prosecution and maintenance" of patents and patent applications shall be deemed
to include, without limitation, the conduct of interferences or oppositions,
and/or requests for re- examinations, reissues or extensions of patent terms.
[*] reasonably informed as to the status of the Patent Rights. [*] in a timely
manner concerning (i) the scope and content of all patent applications within
the Patent Rights, and (ii) content of and proposed responses to official
actions of the United States Patent and Trademark Office and foreign patent
offices during the prosecution of any patent applications within the Patent
Rights. For purposes of this Section 9.1, "timely" shall mean sufficiently in
advance of any decision by [*] or any deadline imposed upon the written response
by [*] so as to allow [*] to meaningfully review such decision or written
response and also provide comments to [*] in advance of such decision or
deadline to allow comments of [*] with respect to the Patent Rights to be
considered and incorporated into [*] decision or written response. [*] of any
election not to pursue the prosecution or maintenance of a patent application or
patent within the Patent Rights reasonably in advance of any applicable
deadlines.

          9.2     Payments by [*].

                  9.2.1 From and after the Effective Date, [*] for all
reasonable costs associated with prosecuting and maintaining the patents within
the Patent Rights; provided, that [*] prior approval shall be required for any
costs in excess of [*], other than any previously approved costs, which approval
shall not be withheld unreasonably. If [*] for the prosecution and maintenance
of an application or patent within the Patent Rights, in any country it shall
promptly notify [*]. If [*] with respect to an application or patent within the
Patent Rights in [*] the subject patent or patent application, respectively,
shall cease to be within the Patent Rights in such country for purposes of this
Agreement. If [*] with respect to an application or patent within the Patent
Rights in any country other than those listed in the preceding sentence, the
license granted to Licensee under such application or patent (as the case may
be) shall [*].

                  9.2.2 It is understood that a potential exists that subject
matter covered by the Patent Rights may overlap with subject matter covered by
certain other patent rights owned or controlled by Licensee. Although the
parties are not aware of the extent of such overlap, if any, as of the Effective
Date, in the course of prosecuting the patents it is anticipated that such an
overlap may become


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                                      -11-
<PAGE>   12
known. Both SKCC and Licensee desire to resolve any such issues amicably, and
therefore agree to use good faith efforts to resolve, without the expense and
resources of formal adversary proceedings, any issues that may arise with
respect to such overlapping subject matter. So that SKCC will not have an undue
advantage in resolving such issues, it is agreed [*].


                                   ARTICLE 10

                            CONFIDENTIAL INFORMATION

          The parties acknowledge and agree that Exhibits A and B contain
confidential information of SKCC. Licensee agrees not to use such confidential
information except as expressly authorized in this Agreement or the Research
Agreement, and shall use reasonable efforts to prevent the disclosure of such
confidential information to third parties; provided, that Licensee may disclose
such confidential information to third parties if Licensee discloses such
confidential information with the same degree of protection that Licensee uses
when it discloses its own confidential information. Notwithstanding the
foregoing, Licensee shall not disclose the contents of Exhibit B to a third
party without SKCC's approval.


                                   ARTICLE 11

                                     GENERAL

          11.1 Obligation to Exploit. Licensee shall [*] bring Licensed Products
to market and to meet the market demand therefor.

          11.2 Complete Agreement. This Agreement, together with the Research
Agreement, constitutes the entire understanding and only agreement between the
parties with respect to the subject matter hereof and supersedes any and all
prior negotiations, representations, agreements, and understandings, written or
oral, that the parties may have reached with respect to the subject matter
hereof. No agreements altering or supplementing the terms hereof may be made
except by means of a written document signed by the duly authorized
representatives of each of the parties hereto. It is understood that the
Research Agreement is separate and independent from this Agreement.

          11.3 No Implied Obligations. Licensee's sole obligation to exploit the
Licensed Subject Matter is as set forth in Section 11.1. Nothing in this
Agreement shall be deemed to require Licensee to otherwise exploit the Licensed
Subject Matter nor prevent Licensee from commercializing products similar to or
competitive with a Licensed Product.

          11.4 Assignment. This Agreement may not be assigned by either party
without the prior written consent of the other party, except to a party that
succeeds to all or substantially all of such party's business or assets relating
to this Agreement whether by sale, merger, operation of law or


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               separately with the Commission. Confidential treatment has been
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                                      -12-
<PAGE>   13
otherwise; provided that such assignee or transferee agrees in writing to be
bound by the terms and conditions of this Agreement. SKCC may assign its right
to receive payments hereunder upon prior written notice to Licensee.

          11.5 Force Majeure. In the event either party hereto is prevented from
or delayed in the performance of any of its obligations hereunder by reason of
acts of God, war, strikes, riots, storms, fires, or any other cause whatsoever
beyond the reasonable control of the party, the party so prevented or delayed
shall be excused from the performance of any such obligation to the extent and
during the period of such prevention or delay.

          11.6 Notices. Any notice or other communication required by this
Agreement shall be made in writing and given by prepaid, first class, certified
mail, return receipt requested, and shall be deemed to have been served on the
date received by the addressee at the following address or such other address as
may from time to time be designated to the other party in writing:

                  If to SKCC:               David Wood
                                            Sidney Kimmel Cancer Center
                                            3099 Science Park Road
                                            San Diego, CA 92121

                  If to Licensee:           David G. Nance, President
                                            Introgen Therapeutics, Inc.
                                            301 Congress Avenue
                                            Suite 2025
                                            Austin, TX 78701

          11.7 Compliance with Law. Licensee shall comply with all applicable
federal, state and local laws and regulations in connection with its activities
pursuant to this Agreement.

         11.8 Governing Law. This Agreement shall be governed by, and construed
and interpreted in accordance with, the laws of Texas, without regard to
conflicts of laws principles.

          11.9 Dispute Resolution. Any controversy or claim arising out of or
relating to this Agreement, or the existence, validity, breach or termination of
this Agreement, whether during or after its term, will be reasonably promptly
and finally settled by arbitration in accordance with the Commercial Arbitration
Rules of the American Arbitration Association, as modified or supplemented
below:

                  (a) The arbitration proceeding will take place in Austin,
Texas if a proceeding is brought by SKCC or in San Diego, California if a
proceeding is brought by Licensee.

                                      -13-
<PAGE>   14
                  (b) The arbitral award will be the exclusive remedy of the
parties for all claims, counterclaims, issues or accounting presented or pled to
the arbitrators. The award will include reasonable attorneys fees and costs.

                  (c) Nothing in this Section 11.9 will prevent a party from
seeking injunctive relief against the other party from any judicial or
administrative authority pending the resolution of a dispute by arbitration.

          11.10 No Waiver. A waiver, express or implied, by either SKCC or
Licensee of any right under this Agreement or of any failure to perform or
breach hereof by the other party hereto shall not constitute or be deemed to be
a waiver of any other right hereunder or of any other failure to perform or
breach hereof by such other party, whether of a similar or dissimilar nature
thereto.

          11.11 No Consequential Damages. IN NO EVENT SHALL EITHER PARTY BE
LIABLE FOR SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF ANY
BREACH OF THIS AGREEMENT; PROVIDED, THAT IF SKCC IS OBLIGATED TO PAY SUCH
DAMAGES TO THIRD PARTIES UNDER ARTICLE 7, LICENSEE SHALL BE LIABLE FOR SUCH
DAMAGES TO THE EXTENT PROVIDED IN ARTICLE 7.

          11.12 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.

          11.13 Severability. If any provision of this Agreement shall be found
by a court to be void, invalid or unenforceable, the same shall be reformed to
comply with applicable law or stricken if not so conformable, so as not to
affect the validity or enforceability of the remainder of this Agreement.

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

         IN WITNESS WHEREOF, the parties hereto have caused their duly
authorized representatives to execute this Agreement.


SIDNEY KIMMEL CANCER CENTER            INTROGEN THERAPEUTICS, INC.
("SKCC")                               ("Licensee")


By:/s/ DAVID WOOD                      By:/s/ DAVID NANCE
   -------------------------------        -------------------------------------
Name: David Wood                       Name: David Nance
     -----------------------------          -----------------------------------
Title: Executive Vice President        Title: President
      ----------------------------           ----------------------------------

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<PAGE>   15
                                    EXHIBIT A

                                  PATENT RIGHTS


                                       [*]




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               separately with the Commission. Confidential treatment has been
               requested with respect to the omitted portions.
<PAGE>   16
                                    EXHIBIT B

                             EXISTING PATENT RIGHTS

                                       [*]




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               separately with the Commission. Confidential treatment has been
               requested with respect to the omitted portions.
<PAGE>   17
                                    EXHIBIT C

              MINIMUM TERMS AND CONDITIONS OF SUBLICENSE AGREEMENTS


Licensee shall include or reference in any sublicense agreement at a minimum
terms and conditions between Licensee and the Sublicensee substantially similar
to the following:

1.       The terms contained in [*]; and

2.       The following disclaimer:

                  SUBLICENSEE ACKNOWLEDGES AND AGREES THAT THE LICENSED SUBJECT
                  MATTER IS SUBJECT TO THE TERMS OF A LICENSE AGREEMENT (THE
                  "LICENSE AGREEMENT") BETWEEN SIDNEY KIMMEL CANCER CENTER
                  ("SKCC") AND LICENSEE. SKCC MAKES NO REPRESENTATIONS AND
                  EXTENDS NO WARRANTIES TO SUBLICENSEE OF ANY KIND, EITHER
                  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO WARRANTIES OF
                  NONINFRINGEMENT OF THIRD PARTY PROPRIETARY RIGHTS,
                  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND
                  VALIDITY OF PATENT RIGHT CLAIMS, ISSUED OR PENDING.



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               separately with the Commission. Confidential treatment has been
               requested with respect to the omitted portions.



<PAGE>   18
                                    EXHIBIT D

                                  PUBLICATIONS

                                       [*]



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               separately with the Commission. Confidential treatment has been
               requested with respect to the omitted portions.