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                                                                EXHIBIT 10.27(a)

                    EVALUATION AND EXCLUSIVE OPTION AGREEMENT

         This Evaluation and Exclusive Option Agreement (the "Agreement") is
made as of _______, 1998 (the "Effective Date") by and between LXR
Biotechnology, Inc., a Delaware corporation, having a place of business at 1401
Marina Way South, Richmond, CA 94804 ("LXR") and Introgen Therapeutics, Inc., a
Delaware corporation, having a place of business at 301 Congress Avenue, suite
2025, Austin, TX 78701 ("Introgen").

                                   BACKGROUND

         A. LXR owns certain Patent Rights (as defined below) relating to the
"bak" gene;

         B. Introgen desires to evaluate the Patent Rights and Related
Technology (as defined below) to determine whether Introgen desires to obtain an
exclusive license under the Patent Rights and Related Technology subject to the
terms and conditions set forth in the License Agreement Outline of Terms in
Exhibit A attached hereto and made a part hereof (the "Term Sheet"); and

         C. LXR desires to grant to Introgen an option to obtain an exclusive
license under the Patent Rights and Related Technology, all on the terms and
conditions set forth herein below.

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

         1. DEFINITIONS. As used in this Agreement, the following capitalized
terms shall have the meanings indicated:

            1.1 "Evaluation Period" shall mean the period commencing on the
Effective Date and ending [*] after Introgen's receipt of Samples hereunder.

            1.2 "Field" shall mean [*]. For the purposes of this Agreement, the
"bak" gene shall include all fragments, derivatives and splice variants thereof;
a "derivative" shall mean a nucleotide sequence directly derived from the "bak"
gene claimed in the Existing Patent Rights defined in Section 1.5.1 (i.e., the
"bak" gene described in Exhibit B hereto and made a part hereof), the gene
product of which has a apoptotic activity substantially similar to that of the
protein encoded by the gene described in Exhibit B.



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            1.3 "License Agreement" shall have the meaning set forth in the
provisions of Article 5 below.

            1.4 "Patented Product" shall mean any product containing or
encompassing the "bak" gene, the manufacture, use of sale of which would, but
for the license granted under the License Agreement, infringe a Valid Claim (as
that term is defined in Exhibit A) of the Patent Rights in the country where it
is sold. "Non-Patented Product" shall mean any product containing or
encompassing the "bak" gene that embodies Related Technology, but the
manufacture, formulation or use thereof is not the subject of any patent
application or patent, or any issued patents covering such product have been
abandoned or declared invalid in a non-appealable order. For the purposes of
this Agreement, a Patented Product or Non-Patented Product shall be individually
referred to herein as a "Licensed Product", and collectively referred to herein
as "Licensed Products".

            1.5 "Patent Rights" shall mean any and all rights in:

                1.5.1 all worldwide patents and patent applications claiming the
subject matter claimed in U.S. Patent Application numbers: [*], filed [*] and
[*], field [*], and in U.S. Patent Number [*], and any foreign counterparts of
the foregoing, existing as of the Effective Date (the "Existing Patent Rights");
and

                1.5.2 all divisions, continuations, continuations-in-part,
foreign counterparts, patents of addition, and substitutions of, and all patents
issuing on any of the foregoing or of any patent application which claim
priority from any Existing Patent Rights, together with all registrations,
reissues, reexaminations, supplementary protection certificates or extensions of
any kind with respect to any of such patents.

            1.6 "Related Technology" shall, subject to the provisions of Section
1.2 (including the exclusions and limitations on the Field set forth therein),
mean all technical information, know-how, processes, procedures, compositions,
methods, techniques, data or other subject matter owned by LXR as of the
Effective Date, and relating to the manufacture, formulation, use or sale of
Licensed Products, and that are necessary or useful for the exercise of the
rights granted under the License Agreement.

         2. EVALUATION.

            2.1 During the Evaluation Period, Introgen agrees to use
commercially reasonable efforts to evaluate the Patent Rights and Related
Technology to determine whether it desires to enter into the License Agreement
as contemplated in Article 5 below (the "Evaluation"). Introgen's Evaluation
shall be limited to the conduct of certain studies [*] using samples of the
"bak" gene that are provided by LXR (the "Samples") for purposes of assessing
[*] of the "bak" gene.

            2.2 If Introgen formulates, modifies and/or tests the Samples in any
way, or conducts any experiments using the Samples, Introgen shall submit all
resulting information and/or test results to LXR. All right, title and interest
in and to all inventions solely made by Introgen or its agents or employees
resulting from the formulation, modification, testing or other experimentation


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with the Samples pursuant to the Evaluation under this Agreement, and any and
all intellectual property rights arising therefrom, shall be owned by Introgen.
All right, title and interest in and to all inventions made jointly by LXR and
Introgen and/or their respective agents or employees resulting from the
formulation, modification, testing or other experimentation with the Samples
pursuant to the Evaluation under this Agreement, and any and all intellectual
property rights arising therefrom, shall be jointly owned by LXR and Introgen.
In that connection, each party shall require and cause its employees and agents
to assign to it any and all inventions made during and in connection with the
Evaluation.

                2.2.1 Introgen hereby agrees to grant to LXR, without payment of
any consideration, an irrevocable, perpetual, transferable, sublicenseable,
royalty-free, non-exclusive, worldwide license under any Introgen Improvement
solely for purposes of manufacturing, selling, importing and using the "bak"
gene for applications outside of the Field. For purposes of the foregoing,
"Introgen Improvement" shall mean any invention solely owned by Introgen (as set
forth in Section 2.2 above) solely consisting of compositions of the "bak" gene
(i.e., fragments, derivatives and splice variants of the "bak" gene described in
Exhibit B or any Patent Rights) or methods of using the "bak" gene (including
fragments, derivatives and splice variants thereof) and all intellectual
property rights (including patent applications and patents) therein. For
avoidance of doubt, Introgen Improvement shall not include subject matter made
outside of the Evaluation. Notwithstanding the foregoing, in the event that
Introgen does not exercise the Option under Section 5 of this Agreement, or if
LXR and Introgen do not enter into the License Agreement, or if the License
Agreement is terminated (but not upon expiration) pursuant to its terms, the
foregoing license shall not be limited to the Field (i.e., in such case, the
words "for applications outside the Field" above shall be replaced with "for all
applications").

                2.2.2 In addition to the rights granted to LXR under Section
2.2.1 above, to the extent that Introgen has the right to do so Introgen hereby
agrees to grant to LXR an option to obtain an exclusive, transferable,
sublicenseable, worldwide license under any Introgen Improvement solely for
purposes of manufacturing, selling, importing and using the "bak" gene for
applications outside of the Field; provided, however, in the event that Introgen
does not exercise the Option under Section 5 of this Agreement, or if LXR and
Introgen do not enter into the License Agreement, or if the License Agreement is
terminated (but not upon expiration) pursuant to its terms, such license shall
not be limited to the Field (i.e., in such case, the words "for applications
outside the Field" above shall be replaced with "for all applications"). After
receipt of notification from Introgen of such an Introgen Improvement, LXR shall
notify Introgen within 60 days whether it desires to exercise the foregoing
option with respect to the particular Introgen Improvement. If LXR so elects the
parties shall negotiate in good faith for a period of [*] the terms and
conditions of an agreement including such license, including milestone and
royalty payments to Introgen; provided, however, such royalty to Introgen shall
not exceed the royalty rates set forth in the "Royalty" section of Exhibit A
hereto and such rates shall be subject to reduction to the same extent as
provided for in the "Royalty" section of Exhibit A.

                2.2.3 With respect to inventions and intellectual property
rights that are jointly owned by LXR and Introgen pursuant to Section 2.2, it is
agreed that unless otherwise expressly provided for herein or in the License
Agreement, neither party shall have an obligation to



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account to the other party for profits, or to obtain the approval of the other
party to license or exploit such jointly-owned intellectual property rights, by
reason of such joint ownership thereof.

                2.2.4 Introgen agrees to provide LXR a copy of all analyses,
compilations, studies or other documents containing the Confidential Information
(as defined below) of LXR prepared by or on behalf of Introgen hereunder for use
in exercising its rights under Sections 2.2.1 and 2.2.2 above. In addition, in
the event that Introgen does not exercise the Option under Section 5 of this
Agreement, or if LXR and Introgen do not enter into the License Agreement, each
party agrees to promptly return to the other party such other parties
Confidential Information.

            2.3 Introgen shall notify LXR promptly in writing as soon as
Introgen determines not to exercise the Option (as defined in Section 5) and
further agrees to provide LXR, upon LXR's request, in reasonable detail, the
basis for such determination. This Agreement will terminate automatically upon
the giving of such notice by Introgen and the provisions of Section 8.3 shall
apply.

         3. NO IMPLIED LICENSE. Nothing in this Agreement shall be construed as
a grant to Introgen of any license, express or implied, under any of LXR's
intellectual property rights (including but not limited to Patent Rights and
Related Technology) relating to the "bak" gene or any Licensed Products or their
manufacture, formulation, use or sale.

         4. CONSIDERATION. In consideration of the Option granted by LXR to
Introgen hereunder, Introgen agrees to pay to LXR a non-refundable fee of [*].

         5. OPTION TO ENTER LICENSE AGREEMENT. LXR hereby grants to Introgen an
exclusive option (the "Option") exercisable at any time during the Evaluation
Period to enter into a license agreement with LXR pursuant to which LXR shall
grant to Introgen an exclusive, worldwide license, with the right to grant
sublicenses subject to LXR's approval as set forth in Exhibit A, under the
Patent Rights and Related Technology to make, have made, use and sell Licensed
Products, practice any method, process or procedure and otherwise exploit the
Patent Rights and Related Technology, and to have any of the foregoing performed
on its behalf by a third party, in each case solely for applications within the
Field (the "License Agreement"), subject to the terms and conditions set forth
in the Term Sheet and such other additional terms and conditions agreed to by
the parties in the License Agreement.

            5.1 Exercise of the Option. Introgen may exercise the foregoing
Option at any time during the Evaluation Period by providing written notice to
LXR declaring Introgen's desire to commence good faith negotiations to enter
into the License Agreement. If Introgen so elects to exercise the Option, the
parties agree to promptly commence negotiations in good faith of the License
Agreement for a period of [*] days.

            5.2 Exclusive Negotiation. It is agreed that, unless this Agreement
is terminated by Introgen under Section 8.2 before the end of the Evaluation
Period, during the Evaluation Period (until such time that Introgen exercises
the Option) and during the [*] day period described in Section 5.1, LXR
shall not engage in discussions or negotiate with any third party regarding the



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licensing of rights with respect to the "bak" gene for use in the Field, nor
shall LXR enter into any agreement with a third party regarding use of the "bak"
gene in the Field.

            5.3 Arbitration. In the event that LXR and Introgen do not enter
into the License Agreement within [*] after Introgen's exercise of the Option
under Section 5.1, Introgen shall have the right to (i) initiate a binding
arbitration proceeding, pursuant to which the terms and conditions of the
License Agreement shall be established by such panel of three (3) arbitrators in
accordance with the Term Sheet by notifying LXR in writing within thirty (30)
days after the end of such [*] period; or (ii) allow the Option to lapse by so
notifying LXR in writing within such thirty (30) day period. Any arbitration
under this Section 5.3 shall be held in Palo Alto, California under the
then-current Commercial Rules of the American Arbitration Association by a panel
of three (3) arbitrators appointed as set forth below. The arbitrators shall
have significant experience in the area of the research and development of
biotechnology products. Any judgment upon the award rendered by the arbitrators
may be entered in any court having jurisdiction thereof. In any arbitration
pursuant to this Section 5.3, the award shall be rendered by a majority of the
three (3) arbitrators, one (1) of whom shall be appointed by each party and the
third of whom shall be appointed by mutual agreement of the two (2)
party-appointed arbitrators. In the event of failure of a party to appoint an
arbitrator within thirty (30) days after commencement of the arbitration
proceeding or in the event of failure of the two (2) party-appointed arbitrators
to agree upon the appointment of the third arbitrator within sixty (60) days
after commencement of the arbitration proceeding, such arbitrator shall be
appointed by the American Arbitration Association in accordance with the
Commercial Rules. The arbitrators shall apply the laws of the State of
California in any such arbitration. The costs of the arbitration, including
administrative fees and fees of the arbitrator, shall be shared equally by the
parties.

         6. CONFIDENTIALITY.

            6.1 Confidential Information. Except as provided herein, each party
shall maintain in confidence, and shall not (a) use for any purpose except as
explicitly provided in Section 2 of this Agreement or (b) disclose to any third
party, any information, data or materials (whether of a business or technical
nature and in whatever form) disclosed by the other party in writing and marked
"Confidential" or that is disclosed orally and confirmed in writing as
confidential within forty-five (45) days following such disclosure
(collectively, "Confidential Information"). It is agreed that Samples and other
materials provided by LXR to Introgen shall be deemed Confidential Information
of LXR. Introgen shall not disclose any Confidential Information of LXR to its
directors, officers, employees or agents except on a need-to-know basis and only
under a similar binder of non-use and non-disclosure, subject to Section 2. It
is agreed that the furnishing of Confidential Information by one party to the
other party hereunder does not and shall not constitute any grant, option or
license to the receiving party under any patent or other rights now or hereafter
held by the disclosing party with respect to such Confidential Information.
Confidential Information shall not include any information that is: (i) already
known to the receiving party at the time of disclosure hereunder (other than
from the other party hereto) as demonstrated by its written records, (ii) now or
hereafter becomes publicly known other than through acts or omissions of the
receiving party, or anyone to whom the receiving party disclosed such
information, (iii) disclosed to the receiving party by a third party under no
obligation of confidentiality to the disclosing party or any other party, or
(iv) subject to Section 2.2, independently developed by the receiving party


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without reliance on the Confidential Information of the disclosing party as
shown by its written records.

            6.2 Permitted Usage. The receiving party may use or disclose
Confidential Information of the disclosing party to the extent necessary to
exercise its rights hereunder (including Introgen's performing the Evaluation or
exercising its rights under the License Agreement) or in filing for, prosecuting
or maintaining any proprietary rights (including patents), prosecuting or
defending litigation, or complying with applicable governmental regulations;
provided, however, if the receiving party is required by law or a court of
competent jurisdiction to make any public disclosures of Confidential
Information of the disclosing party, to the extent it may legally do so, it will
give reasonable advance notice to the disclosing party of such disclosure and
will use its reasonable good faith efforts, or, at the option of the disclosing
party, enable the disclosing party, to secure confidential treatment of
Confidential Information prior to its disclosure (whether through protective
orders or otherwise). It is understood that in the event the License Agreement
is entered into by and between LXR and Introgen, Introgen shall have the right
to continue to use Confidential Information of LXR to exercise its rights
thereunder as to be set forth therein.

            6.3 Prohibited Actions. Subject to Section 6.1 above, Introgen
hereby agrees to consult with LXR prior to filing any patent application
containing any claim the subject matter of which contains, is based upon, or is
derived from the Confidential Information of LXR. In addition, the parties agree
to consult with respect to the filing and prosecution of patent applications
claiming inventions that are jointly owned under Section 2.2 above. Moreover,
Introgen shall not use Confidential Information of LXR for any purpose or in any
manner which would constitute a violation of any laws or regulations of the
United States.

            6.4 Injunctive Relief. The parties recognize that any breach of this
Article 6 would irreparably harm the disclosing party, and that the disclosing
party is thereby entitled to equitable relief (including without limitation,
injunctions) with respect to any such breach or potential breach by the
receiving party, in addition to any other remedies.

            6.5 Retroactive Effect. This Article 6 shall be made retroactive to
March 7, 1998, the date on which the parties commenced their discussions
regarding the subject matter of this Agreement.

         7. WARRANTIES.

            7.1 LXR. LXR hereby represents and warrants to Introgen that as of
the Effective Date (i) it has the right to enter into this Agreement and grant
the Option granted herein, (ii) it has not granted and will not grant during the
term of this Agreement rights in or to the Patent Rights or Related Technology
that would prevent LXR from entering into the License Agreement; and (iii) to
its knowledge, there are no claims of third parties that would prohibit or
restrict LXR from granting to Introgen the Option contemplated hereunder.

            7.2 Introgen. Introgen hereby represents and warrants to LXR that
(i) it has the right to enter into this Agreement, and (ii) to its knowledge,
there are no claims of third parties that would prohibit or restrict Introgen's
ability to perform its obligations under this Agreement. Introgen






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further warrants that no use will be made of any information, data or Samples
provided by LXR to Introgen under this Agreement other than for purposes of
Evaluation of the "bak" gene through the conduct of [*] in the laboratory
setting only as provided under Section 2, and such use shall be in accordance
with all applicable laws and regulations, including without limitation, current
Good Laboratory Practices (as applicable), and that no studies, tests or trials
using such information, data or Samples will be used in or for humans in the
course of the Evaluation.


            7.3 Disclaimer of Warranties and Limitation of Liability. EXCEPT AS
PROVIDED IN THIS ARTICLE 7, NEITHER PARTY MAKES ANY WARRANTIES OR
REPRESENTATIONS (EXPRESS, IMPLIED, STATUTORY OR OTHERWISE) WITH RESPECT TO THE
SUBJECT MATTER HEREOF INCLUDING, BUT NOT LIMITED TO ANY PATENT, TRADEMARK,
SOFTWARE, NON-PUBLIC OR OTHER DATA OR INFORMATION, OR TANGIBLE RESEARCH PROPERTY
INCLUDING SAMPLES. LXR SPECIFICALLY DISCLAIMS ANY AND ALL IMPLIED WARRANTIES OR
REPRESENTATIONS OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. NOTHING
IN THIS AGREEMENT SHALL BE CONSTRUED AS A REPRESENTATION MADE OR WARRANTY GIVEN
BY LXR: WITH REGARD TO THE UTILITY OF ANY SAMPLES; THE SCOPE, VALIDITY OR
ENFORCEABILITY OF THE PATENT RIGHTS; THAT ANY PATENT WILL ISSUE BASED UPON ANY
PENDING PATENT APPLICATION INCLUDED IN THE PATENT RIGHTS; OR THAT THE EXERCISE
OF THE PATENT RIGHTS OR USE OF THE RELATED TECHNOLOGY WILL NOT INFRINGE THE
PATENT OR PROPRIETARY RIGHTS OF ANY OTHER THIRD PARTY. TO THE EXTENT SAMPLES ARE
FURNISHED HEREUNDER, LXR MAKES NO REPRESENTATION THAT SUCH SAMPLES OR THE
METHODS USED IN MAKING OR USING SUCH SAMPLES ARE FREE FROM LIABILITY FOR PATENT
INFRINGEMENT. LXR SHALL HAVE NO LIABILITY OF ANY KIND WHATSOEVER TO INTROGEN
RESULTING FROM THE EVALUATION HEREUNDER, WHETHER SUCH LIABILITY ARISES IN
CONTRACT, TORT OR STRICT LIABILITY, WITH THE EXCEPTION OF INTROGEN'S DEFEND,
INDEMNIFY AND HOLD HARMLESS OBLIGATIONS UNDER SECTION 9, IN NO EVENT WILL EITHER
PARTY BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL OR CONSEQUENTIAL DAMAGES
RESULTING FROM THE EVALUATION HEREUNDER (INCLUDING THE USE OF THE PATENT RIGHTS,
RELATED TECHNOLOGY OR SAMPLES), EVEN IF SUCH PARTY HAS BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.

         8. TERM/TERMINATION.

            8.1 Term. The term of this Agreement shall commence on the Effective
Date and shall continue in full force and effect until expiration of the
Evaluation Period, unless sooner terminated as expressly provided herein. In the
event the License Agreement is entered into by and between LXR and Introgen,
this Agreement shall be superseded thereby and, thereafter any and all
provisions of this Agreement other than those expressly provided to survive
under Section 8.4 shall cease to be effective.

            8.2 Termination. Introgen shall have the right to terminate this
Agreement upon written notice to LXR at any time before expiration of the
Evaluation Period and the provisions of



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Section 2.2, 6.2 and 8.3 shall apply. This Agreement shall automatically
terminate if Introgen commits a material breach or defaults in the performance
of a material obligation hereunder, and fails to remedy or cure such breach or
default within thirty (30) days after being called upon in writing to do so by
LXR.


            8.3 Effect of Termination. Upon expiration or termination of this
Agreement for any reason other than by execution of the License Agreement,
Introgen shall return to LXR and shall cease all use of all Confidential
Information of LXR including without limitation, all information, data,
materials, Samples and documents provided by LXR under this Agreement, except
that Introgen may retain one (1) copy of such information, data and documents in
the files of its legal counsel solely for the purposes of complying with its
ongoing confidentiality obligations hereunder. All consideration paid for the
Option pursuant to Section 4 shall be retained by LXR.

            8.4 Survival. Section 2.2, 5.2, and 8.3, and Article 3, 6, 7, 9 and
10 shall survive the expiration or termination of this Agreement.

         9. INDEMNIFICATION.

            9.1 Indemnification. Introgen shall indemnify, defend and hold
harmless LXR, its affiliates, and their respective directors, officers,
employees, agents, successors and assigns (the "Indemnitees") against any
liability, damage, loss, cost or expense (including reasonable attorneys' fees
and expenses of litigation, regardless of outcome) incurred by or imposed upon
the Indemnitees, or any one of them, in connection with any third party claims,
suits, actions demands or judgments arising out of any acts or omissions by or
on behalf of Introgen pursuant to this Agreement or the Materials Transfer
Agreement, or any negligence, misconduct or breach of this Agreement or the
Materials Transfer Agreement by Introgen or its employees, agents or
contractors; provided that an Indemnitee that intends to claim indemnification
under this Section 9 shall: (i) promptly notify Introgen in writing of such
claim, suit or action with respect to which Indemnitee intends to claim such
indemnification, (ii) subject to Section 9.3., give Introgen sole control of the
defense and/or settlement thereof, (iii) provide Introgen, at Introgen's
expense, with reasonable assistance and full information with respect thereto.
Notwithstanding the foregoing, Introgen shall have no obligations for any claim
if the Indemnitee seeking indemnification makes any admission or settlement
regarding such claim without the prior written consent of Introgen, which
consent shall not be unreasonably withheld.

            9.2 Exception. Introgen's indemnification under Section 9.1 shall
not apply to any liability, damage, loss, cost or expense to the extent
attributable to the gross negligence or intentional misconduct of the
Indemnitees.

            9.3 Attorneys. Introgen agrees at Introgen's sole expense, to
provide counsel reasonably acceptable to LXR to defend against any actions
brought or filed against any Indemnitee with respect to any indemnification
obligation herein, whether or not such actions are rightfully brought. LXR shall
have the right to participate with counsel of its own choosing at its own
expense.




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<PAGE>   9

         10. MISCELLANEOUS.

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

             10.2 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, or such party's accountants, attorneys and
other professional advisors, potential investors and partners, under binders of
confidentiality no less stringent than those contained herein.

             10.3 Assignment. This Agreement shall not be assignable by either
party to any third party without the prior written consent of the other party
hereto. Notwithstanding the foregoing, either party may assign this Agreement
without the consent of the other party to a party that is an affiliate of the
assigning party at the time of the assignment, or to an entity that acquires
substantially all of the business or assets of such party whether by merger,
acquisition, sale or otherwise, provided that in either case, such assignee
agrees in writing to be bound by the terms and conditions of this Agreement. In
the event of any such assignment all references to the assigning party shall be
deemed to be references to the assignee. Any purported assignment in violation
of this section shall be null and void. For the purposes hereof, an "affiliate"
of a party shall mean any corporation or other business entity that controls, is
controlled by or under common control with such party.

             10.4 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 by the other party in writing:

             If to LXR:         LXR Biotechnology, Inc.
                                1401 Marina Way South
                                Richmond, CA  94804
                                Attention:  Donald Picker
                                Phone:  (510) 412-9100
                                Fax: (510) 412-9109

             If to Introgen:    Introgen Therapeutics, Inc.
                                301 Congress Avenue, Suite 2025
                                Austin, Texas 78701
                                Attn:  David Nance
                                Phone:  (512) 320-4169
                                Fax: (512) 320-6166



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             10.5 Compliance with Law. Each party shall comply with all
applicable federal, state and local laws and regulations in connection with its
activities pursuant to this Agreement. Each party hereby acknowledges that its
rights and obligations under this Agreement are subject to the laws and
regulations of the United States relating to the export of products and
technical information. Without limitation, each party shall comply with all such
laws and regulations.

             10.6 Governing Law. This Agreement shall be governed by, and
construed and interpreted in accordance with, the laws of the State of
California, without reference to its or any other jurisdiction's principles of
conflicts of law.

             10.7 No Waiver. A waiver, express or implied, by either LXR or
Introgen 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.

             10.8 Severability. If any provision of this Agreement shall be
found by a court to be void, invalid or unenforceable, the same shall be
conformed 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.

             10.9 Entire Agreement. This Agreement (including the Exhibits
hereto) constitutes the entire understanding of the agreement between the
parties with respect to the subject matter hereof and supersede 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.

             10.10 Counterparts. This Agreement shall 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.

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

LXR BIOTECHNOLOGY, INC.                 INTROGEN THERAPEUTICS, INC.


By:                                     By:
   --------------------------------        -------------------------------------

Name:                                   Name:
     ------------------------------          -----------------------------------

Title:                                  Title:
      -----------------------------           ----------------------------------





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                                    EXHIBIT A

                                LICENSE AGREEMENT
                                OUTLINE OF TERMS


PARTIES:                   Introgen Therapeutics, Inc. ("Introgen") and LXR
                           Biotechnology, Inc. ("LXR").

DEFINITIONS:               Capitalized terms that are not otherwise defined in
                           this Outline of Terms shall have the meaning defined
                           for such terms in the Evaluation and Exclusive Option
                           Agreement (the "Agreement") to which this Outline of
                           Terms is attached as Exhibit A. Subject to the terms
                           and conditions of the Agreement, Introgen and LXR
                           will enter into a License Agreement, under which LXR
                           will grant to Introgen an exclusive, worldwide
                           license, with the right to grant and authorize
                           sublicenses, under the Patent Rights and Related
                           Technology to make, have made, use and sell Licensed
                           Products, practice any method, process or procedure
                           and otherwise exploit the Patent Rights and Related
                           Technology, and to have any of the foregoing
                           performed on its behalf by a third party, in each
                           case solely for applications within the Field.
                           Notwithstanding the foregoing, LXR shall have the
                           right to approve any sublicense granted by Introgen
                           to a third party (where such third party has a
                           capitalization of less than [*] as determined by
                           Introgen and such third party in good faith), which
                           approval shall not be unreasonably withheld;
                           otherwise, LXR shall have no right to approve
                           sublicenses. In addition, in the event that Introgen
                           grants a sublicense under the Patent Rights and
                           Related Technology to any party, it agrees to provide
                           LXR a copy of such agreement (reasonably redacted).

                           A "Valid Claim" means any claim contained in any
                           patent application or in any issued patent included
                           within the Patent Rights, which has not been
                           abandoned or declared invalid in a non-appealable
                           order, as the case may be, and which would be
                           infringed by the manufacture, use, sale, offer for
                           sale or import of a Licensed Product in the absence
                           of the license granted under the License Agreement;
                           provided that, in the case of a patent application
                           that has not issued, not more than [*] has elapsed
                           from the filing date to which the claim is entitled.

DATA:                      Promptly following the execution of the License
                           Agreement and for the duration of the License
                           Agreement, to the extent LXR may legally do so, LXR
                           will provide to Introgen all data,

      [*] 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.




<PAGE>   12


                           materials (including reasonable samples of biological
                           materials), reports, analyses and other information
                           in its possession necessary for Introgen to exercise
                           its rights under the license granted for use in the
                           Field. Introgen may provide such data, materials and
                           other information, on a need-to-know basis, to those
                           third parties who require such data, materials or
                           information in order to (i) obtain regulatory
                           approvals to manufacture and market Licensed Products
                           for use in the Field, or (ii) commercialize Licensed
                           Products for use in the Field, under binders of
                           confidentiality no less stringent than those
                           contained in the Agreement. LXR shall have the right,
                           without restriction, to use any and all such data,
                           materials, reports, analyses and other information
                           for uses outside the Field.

                                       [*]


      [*] 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.



                                      -ii-

<PAGE>   13


                           [*].

MILESTONES:                Introgen will pay to LXR the following amounts in
                           United States dollars (which amounts shall be
                           non-refundable) upon accomplishment of each of the
                           following milestones with respect to the first
                           Licensed Product for which such milestone is
                           accomplished:

                           [*]         Upon the first successful completion of
                                       [*] for the first Licensed Product.

                           [*]         Upon the first successful completion [*]
                                       for the first Licensed Product; and

                           [*]         Upon first [*] of the first Licensed
                                       Product in the [*].

                           A phase of clinical trials for a Licensed Product
                           shall be deemed to be "successfully completed" when
                           all studies appropriate to that phase have been
                           completed to the reasonable satisfaction of Introgen,
                           and Introgen certifies in writing to LXR such
                           satisfactory completion.

                           Introgen will be responsible for all costs and
                           expenses of developing, testing and registering
                           Licensed Products and for obtaining and maintaining
                           regulatory approvals therefor, and for all costs of
                           manufacturing, promoting, marketing and selling
                           Licensed Products.

ROYALTIES:                 Introgen will pay to LXR royalties at the rate of
                           [*] of Net Sales by Introgen, its affiliates and
                           sublicensees of Patented Products to unaffiliated
                           third parties, such royalties to be paid quarterly.
                           Such [*] royalty rate shall apply even if the
                           Patented Product includes the "bak" gene and



      [*] 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.


                                     -iii-


<PAGE>   14


                           one or more other products and/or technologies
                           (including without limitation delivery systems
                           therefor). [*] royalty payment shall continue on a
                           country-by-country basis until the later of: [*] from
                           the first commercial sale of a Patented Product in a
                           particular country, or the last to expire of any
                           Valid Claim under the Patent Rights in such country.

                           In addition to the foregoing, in those countries
                           where Non-Patented Products are sold, Introgen will
                           pay to LXR royalties for know-how included in the
                           Related Technology at the rate of [*] of Net Sales of
                           Non-Patented Products by Introgen, its affiliates and
                           sublicensees to unaffiliated third parties, such [*]
                           royalties to be paid quarterly. Such [*] royalty rate
                           shall apply even if the Non-Patented Product includes
                           the "bak" gene and one or more other products and/or
                           technologies (including without limitation delivery
                           systems therefor). Such [*] royalty payment for
                           know-how shall continue on a country-by-country basis
                           until [*] from the first commercial sale of a
                           Non-Patented Product in a particular country.
                           Notwithstanding the foregoing, if during such [*], a
                           patent application covering the manufacture,
                           formulation or use of a Non-Patented Product is filed
                           in such country, then the royalty rate shall increase
                           to [*] from the date such patent application is
                           filed, and such [*] royalty payment shall continue in
                           such country until the later of: [*] from the first
                           commercial sale of such Licensed Product in that
                           country, or the last to expire of any Valid Claim
                           under the Patent Rights in such country.

                           "Net Sales" will be defined more specifically in the
                           License Agreement to include the gross amounts
                           invoiced by Introgen, its affiliates and sublicensees
                           for the sale of Licensed Products to unaffiliated
                           third parties, less (i) all trade, cash and quantity
                           discounts or government rebates actually granted and
                           taken; (ii) refunds, allowances or credits to
                           customers because of rejections or returns; (iii)
                           prepaid freight, sales taxes, duties and other
                           governmental taxes (including value added tax); and
                           (iv) provisions for uncollectible accounts determined
                           in accordance with reasonable accounting practices,
                           consistently applied to all products of the selling
                           party.

                           In the event a third party claims that the "bak" gene
                           alone, or its use alone infringes such third party's
                           patent rights, and Introgen; or an affiliate or
                           sublicensee becomes obligated to make




      [*] 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.


                                      -iv-


<PAGE>   15
                           payments of any kind to such third party solely with
                           respect to such third party's patent rights covering
                           the "bak" gene or use thereof, provided Introgen's
                           use of the "bak" gene is within the Field, Introgen
                           may deduct [*] of the amounts owing to such third
                           party from the royalty payments owing to LXR under
                           the License Agreement; provided, however, that no
                           royalty payment to be made by Introgen to LXR under
                           the License Agreement shall be reduced by more than
                           [*] of the royalty payment that is otherwise due to
                           LXR under the License Agreement.

DUE DILIGENCE:             Introgen will agree to exercise commercially
                           reasonable efforts to research, develop, manufacture,
                           obtain all necessary governmental approvals for, and
                           sell Licensed Products throughout the world, first in
                           [*] and then in other major markets of the world
                           including but not limited to [*]. The License
                           Agreement will contain other obligations on the part
                           of Introgen relating to its diligence in developing
                           and commercializing Licensed Products.

PATENT PROSECUTION:        LXR will have the right to control prosecution of the
                           Patent Rights. Introgen shall reimburse LXR for [*]
                           the out-of-pocket fees and expenses incurred after
                           the execution of the License Agreement for any and
                           all filing, prosecution and maintenance of patents
                           and patent applications included within the Patent
                           Rights. If LXR elects not to prosecute any patent
                           application or maintain any patent in the Patent
                           Rights, or fails to do so, LXR will notify Introgen
                           and Introgen will have the right to pursue such
                           prosecution or maintenance at Introgen's sole
                           expense. The License Agreement will include
                           provisions for Introgen to be consulted in a timely
                           fashion with respect to the prosecution of the Patent
                           Rights.

ENFORCEMENT:               Introgen shall have the first right to enforce the
                           Patent Rights with respect to infringements within
                           the Field; provided, however if Introgen fails to
                           bring an action to enforce the Patent Right within 6
                           months after LXR's request to do so, LXR shall have
                           the right to bring such action. In either case the
                           noncontrolling party will cooperate in such action at
                           the other's expense. The party initiating any such
                           action will keep the other party reasonably informed
                           of the progress thereof, and such other party will
                           have the right to participate with counsel of its own
                           choice. All awards from such enforcement actions
                           (after reimbursing the parties' costs and expenses
                           related thereto) shall be treated as follows: [*]

      [*] 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.

                                      -v-

<PAGE>   16


                           [*]

PATENT INFRINGEMENT:       If the production, sale or use of any Licensed
                           Product within the Field results in a claim, suit or
                           proceeding alleging patent infringement against
                           Introgen, its affiliates or sublicensees, Introgen
                           will have the exclusive right to defend and control
                           the defense of any such action using counsel of its
                           own choice at its expense; provided, however, that
                           LXR may participate in the defense and/or settlement
                           thereof at its own expense with counsel of its
                           choice. Except as agreed in writing by LXR, Introgen
                           will not enter into any settlement relating to a
                           Licensed Product, if such settlement admits the
                           invalidity or unenforceability of any patent within
                           the Patent Rights. Introgen agrees to keep the LXR
                           reasonably informed of all material developments in
                           connection with any such action. [*].

                           Notwithstanding the foregoing, in the event such
                           claim of infringement does not involve allegations
                           that the manufacture, use or sale of the "bak" gene
                           infringes a third party patent, then Introgen shall
                           defend, indemnify and hold harmless LXR and its
                           affiliates and their respective directors, officers,
                           agents, employees, successors and assigns from and
                           against such claim and any and all liabilities,
                           damages, losses, costs and expenses (including
                           without limitation attorney's fees and costs of
                           litigation, regardless of outcome) arising therefrom,
                           subject to standard indemnification procedure and
                           provided that LXR shall have the right to participate
                           in any such action with counsel of its own choosing
                           at its own expense. [*].

INDEMNIFICATION:           Introgen will defend, indemnify and hold harmless LXR
                           and its affiliates and their respective directors,
                           officers, employees, agents, successors and assigns
                           against any and all claims, liabilities, suits,
                           losses, damages, costs, fees and expenses

      [*] 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.

                                      -vi-

<PAGE>   17

                           (including without limitation attorney's fees and
                           costs of litigation, regardless of outcome) resulting
                           directly or indirectly from Introgen's exercise of
                           the rights under the License Agreement, subject to
                           standard indemnification procedures.

WARRANTIES:                The License Agreement will include all warranties
                           provided in the Agreement and additional warranties
                           on the part of Introgen regarding) the research,
                           development, manufacture and sale of Licensed
                           Products in accordance with all applicable laws and
                           regulations.

                           In addition, LXR will warrant to Introgen that: (i)
                           LXR has the right to enter into the License Agreement
                           and grant the rights granted therein; (ii) LXR has
                           not granted and will not grant during the term of the
                           License Agreement, rights in or to the Licensed
                           Products or Related Technology that are inconsistent
                           with the rights granted to Introgen under the License
                           Agreement, (iii) to the best of its knowledge, as of
                           the effective date of the License Agreement, there
                           are no claims of third parties challenging the right
                           of LXR to grant to Introgen the rights under the
                           License Agreement and (iv) except for the Patent
                           Rights, as of the effective date of the License
                           Agreement, LXR does not own or control any patents or
                           patent applications the claims of which would
                           dominate any practice of the Patent Rights by
                           Introgen under the License Agreement.

MISCELLANEOUS:             The License Agreement will include other customary
                           terms and conditions contained in license agreements
                           of this type.

                           This Term Sheet shall not be binding on LXR and
                           Introgen, and there are no enforceable obligations on
                           the part of either party, other than as set forth in
                           the Agreement, with respect to the matters contained
                           in this Term Sheet, unless and until a definitive
                           License Agreement is fully executed and delivered by
                           the parties. It is understood that any definitive
                           License Agreement will be subject to the prior
                           approval of the parties' respective senior management
                           and Boards of Directors.


                                     -vii-

<PAGE>   18

                                    EXHIBIT B

                                   (ATTACHED)