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                                                                    Exhibit 4.11

                      Effective Date: December 16/th/, 2002



                               LION bioscience AG

                                       and

                            BAYER AKTIENGESELLSCHAFT





                    ----------------------------------------

                                 4/th/ AMENDMENT

                   relating to a development agreement between
                               LION bioscience AG
                                       and
                                    Bayer AG
                           dated 13/th/ October, 2000

                    ----------------------------------------

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                                    CONTENTS

Article                                                                     Page

      Recitals ..............................................................  3
1.    Interpretation ........................................................  4
2.    Continuation of the Development, Acceptance and Termination ...........  5
3.    Project Structure .....................................................  7
4.    Ownership, Rights and Commercialization ...............................  8
5.    Good Faith ............................................................  9
6.    Termination ........................................................... 10
7.    Miscellaneous ......................................................... 10

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THIS AGREEMENT is made as of December 16/th/, 2002

BETWEEN:

LION bioscience AG ("LION"), Waldhofer Str. 98, 69123 Heidelberg, Germany,
registered with the commercial register of the local court in Heidelberg under
HR B 5706

and

Bayer Aktiengesellschaft ("Bayer"), 51368 Leverkusen, Germany.


WHEREAS:

(A) On 13/th/ October, 2000, LION and Bayer entered into a novel and innovative
collaboration (the "Development Agreement") to implement existing IT tools at
Bayer but also to develop novel IT tools, such as pharmacophore informatics
tools, to significantly enhance lead identification and optimization
capabilities for pharmaceutical and agrochemical discovery and development.

(B) LION and Bayer agreed on key modifications to the Development Agreement to
be implemented in the first calendar quarter of 2002, which relate in particular
to the future milestones and payment schedule, in a 1st Amendment to the
Development Agreement dated 1/st/ December, 2001 and signed by LION on 11/th/
December, 2001.

(C) LION and Bayer agreed on modifications of the Development Agreement to be
implemented in the second calendar quarter of 2002, which relate in particular
to the future milestones and payment schedule, in a 2nd Amendment to the
Development Agreement dated March 29/th/, 2002.

(D) On June 14/th/, 2002, the parties agreed that the DELIVERABLES of the new
MILESTONE 2 A as defined in Annex B/II of the 2/nd/ Amendment to the Development
Agreement did not meet the criteria of the ACCEPTANCE TEST according to Annex
E/II of that Amendment.

(E) The parties agreed that the key DELIVERABLES identified by the parties would
not meet the criteria of the ACCEPTANCE TEST in accordance with (S) 3 (3) of the
2/nd/ Amendment to the Development Agreement, which would have allowed Bayer to
terminate the Agreement pursuant to (S) 15 of the Development Agreement.

However, the parties have agreed in the 3/rd/ Amendment to the Development
Agreement dated June 25, 2002 to an procedure trying to meet the criteria of
MILESTONE 2 A.

Testing and inspection of the first two corrections releases which were agreed
upon in the 3/rd/ Amendment identified issues in the correction process that
would allow Bayer to terminate the Agreement pursuant to (S) 2 (1) of the 3/rd/
Amendment.

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 However, the parties agreed on September 4, 2002, to refine the process for
LION to meet the criteria of the ACCEPTANCE TEST for MILESTONE 2A and to
restructure the project for all the work being due beyond MILESTONE 2A.

       On October 7, 2002, Bayer received a final correction release of the due
DELIVERABLES according to MILESTONE 2A - aiming at fulfilling the criteria
according to the modification of Annex B / II of 2nd Amendment which Bayer has
been subjected to a formal, determinative ACCEPTANCE TEST (modification of Annex
E / II of the 2nd Amendment, i.e., excluding Crop Science databases).

LION and Bayer hereby wish to amend and modify the Development Agreement as
follows.


NOW IT IS HEREBY AGREED as follows:


1.       Interpretation

1.1      In this Agreement, including the recitals therein, all terms shall have
         the same meaning as in the Development Agreement unless otherwise
         defined in this Agreement or unless the context requires otherwise.

1.2      This Agreement representing the 4/th/ Amendment to the Development
         Agreement as referred above will supersede the 1/st/ through 3/rd/
         Amendment and all provisions given there, except as provided otherwise
         in this Agreement.

1.3      "MILESTONE" has the meaning given to it in clause 1(8) of the
         Development Agreement.

1.4      "RELEASE" is a defined term and shall mean a body of executable code
         that is packaged, tested and documented with release notes and deployed
         on Bayer servers.

1.5      "KEY RELEASE" is a defined term and shall mean any RELEASE to which the
         corresponding ACCEPTANCE TEST will be applied. The term KEY RELEASE
         will substitute the term MILESTONE beyond MILESTONE 2A - namely
         MILESTONE 2 B, MILESTONE 3, and MILESTONE 4 of the Development
         Agreement and its Amendments. The content of the KEY RELEASES is
         defined in ANNEX 1 and 2.

1.6.     ACCEPTANCE TEST is a defined term as follows: for MILESTONE 2A, the
         term has the meaning given in the 2/nd/ Amendment, ANNEX E/II to the
         Development Agreement which was jointly defined and agreed upon between
         the parties; for future DELIVERABLES, the term has the meaning
         according to Art. 2.6 of this Amendment.

2.       Continuation of the Development, Acceptance and Termination

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         A. As to MILESTONE 2A:

         Following the testing and inspection of the key DELIVERABLES of
         MILESTONE 2A the parties realized the emergence of certain issues which
         would have made the completion of the ACCEPTANCE TEST according to (S)
         3 (3) of the 2/nd/ Amendment to the Development Agreement not possible.
         Therefore, the parties agree to the following understanding in regard
         to the MILESTONES 2A:

2.1      Lion shall repair the bugs and errors of the DELIVERABLES of MILESTONE
         2 A defined in Annex 1 without negative impact on any of the
         functionalities of DELIVERABLES classified as "passed" in the MS2a.4
         ACCEPTANCE TEST report document PIX0036-5 MS2a.4 ATP results.xls. Bayer
         will receive a final correction KEY RELEASE (i.e. R 3.1) for the
         DELIVERABLES according to sentence 1 of this clause including the
         corresponding documentation and the related source code (subject to the
         prior written consent to the delivery of such source code of any third
         party having an ownership interest or rights in such source code; for
         LION's sub-contractor TRIPOS see ANNEX 4) by the date defined in ANNEX
         2 for KEY RELEASE R 3.1.

2.2      In consideration for the DELIVERABLES of MILESTONE 2A, that have passed
         the ACCEPTANCE TEST, for efforts until the Effective Date of this
         Amendment beyond MS2a requirements such as provider simplification and
         performance enhancements, for LION's efforts until the Effective Date
         of this Amendment in RELEASE 2.5 and KEY RELEASE 3.1 to repair
         DELIVERABLES and for the use of LION's L-charts and sub-contractors
         compute engines Bayer will execute the payment of US$ 2,000,000 to Lion
         without delay after the Effective Date of this Amendment - but not
         later than December 20/th/ 2002 - thereby accepting LION's obligations
         with respect to MILESTONE 2A as of the Effective Date (i.e. without any
         right to repayment of this amount). This amount corresponds to
         sub-payment 4 of the Development Agreement. For the avoidance of doubt
         the parties confirm that sub-payment 4 (excluding management fee 4) as
         defined in Annex D of the Development Agreement has been reduced to US$
         2,000,000. Future maintenance and warranty of the Tripos' compute
         engines is specified in a separate agreement between Bayer Crop Science
         and Tripos.

B.       As to the continuation of the Project beyond MILESTONE 2A:

2.3      The parties agree that the overall scope of the Project is defined in
         the Cornerstone proposal attached hereto as as ANNEX 2 and further
         detailed in the DELIVERABLES list attached hereto as ANNEX 5. The
         parties agree to jointly define a project plan including the
         DELIVERABLES for each KEY RELEASE on the basis of the Cornerstone
         Proposal attached hereto as ANNEX 2 and to specify details of certain
         DELIVERABLES of the WORK PACKAGES and the KEY RELEASES three month
         prior to the delivery date according to ANNEX 2 of the respective KEY
         RELEASE considering the provisions of Section 3 and 5 below. For the
         avoidance of doubt, LION committs the timely achieving and delivering
         of the DELIVERABLES of each KEY RELEASE according to ANNEX 2.

2.4      Bayer will itself develop and establish the data integration part of
         the project and terminate those parts directed to Bayer Crop Science.
         Bayer and Lion will continue the


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         WORK PACKAGES Analysis/Visualization, Pharmacophore Identification and
         Project Tracking according to the modified DELIVERABLES list attached
         hereto as ANNEX 5. Bayer and Lion will jointly develop an interface
         between Bayer's warehouse/query engine and the Project Spreadsheet. In
         this context, LION will license to Bayer the software 'LION Discovery
         Center' including updates thereof during the course of the Project
         pursuant to a cost-free, non-exclusive, non-transferable, perpetual
         worldwide license for internal use by Bayer within the scope of this
         Project and to be used with the DELIVERABLES of the Project on a
         perpetual basis for internal purposes only pursuant to license terms
         and conditions to be agreed upon between the parties.

2.5      In accordance with the time frame according to ANNEX 2 Bayer shall
         receive the DELIVERABLES of each newly developed KEY RELEASE and all
         RELEASES developed in realizing the elements of ANNEX 5 fulfilling the
         there defined criteria including - in case of full acceptance of the
         respective WORK PACKAGE, respectively KEY RELEASE - the corresponding
         documentation and the source code (subject to the prior written consent
         to the delivery of such source code of any third party having an
         ownership interest or rights in such source code; for LION's
         sub-contractor TRIPOS see ANNEX 4). For the avoidance of doubt, LION is
         not obliged to provide the source code of its software LION Discovery
         Center as this is not to be seen as a KEY RELEASE or RELEASE.

2.6      Bayer will subject the DELIVERABLES of each KEY RELEASE to a
         corresponding specific ACCEPTANCE TEST that shall be agreed upon
         jointly, in due time (timeframe has to be mutually defined) but not
         later than 30 days prior to the ACCEPTANCE TEST. Bayer will inform LION
         of the outcome of the corresponding ACCEPTANCE TEST and will request
         the repair of any bugs or errors or will advise LION of its definite
         acceptance of such KEY RELEASE, respectively. The parties agree that
         LION will repair the bugs and errors in the KEY RELEASE following the
         KEY RELEASE in question without additional compensation. The definite
         acceptance of a KEY RELEASE is on a per WORK PACKAGE basis.

2.7      Bayer will compensate LION for the development and delivery of the
         DELIVERABLES under the KEY RELEASES - after they have passed the
         corresponding ACCEPTANCE TEST - by paying the sums corresponding to
         each completed WORK PACKAGE of each KEY RELEASE as laid down in ANNEX
         3.

2.8      For the avoidance of doubt, there will not be any further financial
         obligations of Bayer under this Amendment and the Development Agreement
         over and above the provisions of Art. 2.7 in connection with ANNEX 3.

2.9.     In addition to the provisions of Art. 15 of the Development Agreement
         Bayer may terminate the Agreement with immediate effect in the
         following cases:

         -  if LION does not deliver a KEY RELEASE of each WORK PACKAGE at least
            within 60 days after the due date according to ANNEX 2,

         -  if the ACCEPTANCE TEST for any WORK PACKAGE was not passed to a
            degree giving reasonable confidence that the corresponding
            DELIVERABLES

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            may not be accepted after LION's repair.

         -  if LION does not complete the repair of a KEY RELEASE satisfactorily
            as requested by Bayer within 90 days after having been informed of
            the deficit, unless the parties agree to repair the pertinent bugs
            and errors in the KEY RELEASE following the KEY RELEASE in question.

3.       Project structure (superseding (S) 9 of the Development Agreement)

3.1      The executive steering committee shall, subject to good faith and
         man-power limitations as stated in Section 5 approve the specified
         details of the DELIVERABLES of the KEY RELEASES and the respective
         portions and time periods to complete the WORK PACKAGES, and the
         respective ACCEPTANCE TESTs and shall approve any changes in the
         project plans during the period between the KEY RELEASES, provided
         however that the executive steering committee may not approve any
         definitions or other details of any DELIVERABLES of the KEY RELEASES,
         any changes of the KEY RELEASES or any time periods for achieving the
         defined DELIVERABLES or the project plans that would materially enlarge
         or broaden the scope of the Project as originally anticipated in the
         Development Agreement without the consent of LION's representatives in
         the executive steering committee. This consent may not, subject to the
         good faith and man-power limitations as stated in Section 5, be
         unreasonably withheld.

3.2      In the executive steering committee Bayer will be represented by Dr.
         J.-A. Karlsson, Dr. D. Wollweber, Dr. H. Wild, Prof. Dr. M. Schindler
         and Dr. J. Mittendorf - as Bayer's responsible project managers while
         LION will be represented by Dr. F. von Bohlen und Halbach, Dr. R.
         Schneider and Th. Hein - as LION's responsible project manager.
         Following December 31/st/, 2002 Dr. D. Wollweber and Prof. Dr.
         Schindler will leave the executive steering committee.

3.3      Since specific experience in pharmacophore informatics and project
         management are important requirements for the successful execution of
         the topics under the Development Agreement, any change of the project
         manager of LION needs to be approved by Bayer in writing.

3.4      The operational committee as defined in (S) 9 (4) of the Development
         Agreement shall remain unchanged.

3.5      At all stages of the Project, Bayer has the right to elect a new
         partner that could take over the responsibility of LION's
         sub-contractor in case Bayer has confidence that the DELIVERABLES may
         not be achieved in time or accepted by Bayer. Bayer may especially
         require LION to terminate the services of LION's current subcontractor,
         Tripos Ltd., UK and to cooperate with the new partner elected by Bayer
         to achieve the DELIVERABLES in question.

4.       Ownership, Rights and Commercialization

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4.1      Subject to the terms and provisions set forth in this 4/th/ Amendment
         and the Development Agreement, LION hereby grants, and Bayer hereby
         accepts, a non-exclusive, non-transferable, royalty-free worldwide
         perpetual right and license to use, modify or develop further, for its
         and its affiliates' and successors' internal research, discovery and
         development of pharmaceutical and agricultural products, at any of its
         sites, each KEY RELEASE and RELEASE of a WORK PACKAGE accepted by
         Bayer, in object and source code form, provided however that:

         -  for purposes of this Section 4.1, any KEY RELEASE or RELEASE shall
            not include any version of the LION DiscoveryCenter software. The
            license to the use of LION DiscoveryCenter shall be governed by a
            separate license agreement to be entered into by the parties
            pursuant to Section 2.4

         -  if any KEY RELEASE and/or RELEASE incorporates one or more software
            program(s) or routine(s) of a third party, including without
            limitation Tripos, Inc. or Tripos UK Ltd., LION must be authorized
            to (sub)license or deliver the corresponding source code of such
            third party software program(s) or routine(s) to Bayer; LION shall
            use commercially reasonable efforts to obtain such (sub)license or
            authorization;

         -  Bayer will not itself, or allow any parent, subsidiary, affiliate,
            successor, agent, employee, consultant or other third party to: (a)
            sell, lease, license, sublicense, copy, reproduce, market or
            distribute the KEY RELEASES; (b) modify, port, translate, transform,
            localize, or create derivative works of the KEY RELEASES, or any
            portion thereof, for resale or external distribution; (c) provide
            training or consulting to third parties in the use of the KEY
            RELEASES, or enter into time-sharing arrangements for use of the KEY
            RELEASES with third parties; (d) knowingly take any action that
            would cause any KEY RELEASES to be placed in the public domain; (e)
            remove any product identification, trademark, copyright or other
            notices contained in or on KEY RELEASES;

         -  Bayer's use and disclosure of the KEY RELEASES is restricted solely
            to its, its affiliates' and successors' employees; Bayer, its
            affiliates and successors are responsible for the actions of their
            employees; and

         Bayer will not provide access to any portion of the KEY RELEASE,
            including in particular in source code form, to any third party
            other than affiliates and successors, that is not an authorized
            partner of LION, except that upon termination of the Development
            Agreement, Bayer shall be entitled to provide such access to a third
            party contractor or collaborator of Bayer, provided that (A) such
            third party has agreed to maintain the confidentiality of each such
            KEY RELEASE or portion thereof consistent with the requirements
            Bayer ordinarily imposes on third parties that are granted access to
            Bayer's trade secrets or confidential information, (B) such third
            party agrees in writing to use such KEY RELEASE, or any portion
            thereof, only for the benefit of Bayer or the succeeding entity and
            consistent with the scope of Bayer's license and rights, (C) such
            third party shall have no use, distribution, commercialization or
            development rights or license to any derivative works or further
            developments of any such KEY

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            RELEASE, and (D) Bayer notifies LION of the identity of each such
            third party.

4.2      LION shall have the unrestricted right to use, develop further,
         distribute and otherwise commercialize the KEY RELEASES and any other
         results developed in the course of the Project, including in
         particular, PROPRIETARY RESULTS AND NEW SOFTWARE, at any time during
         the term of this Agreement, including the extension period specified in
         this 4/th/ Amendment and any time after termination of the Development
         Agreement as amended. For the avoidance of doubt, the provisions under
         Art. 8.5 of the Development Agreement remain in full force. In case the
         related Software has been developed solely by Bayer, Bayer may grant a
         license to LION regarding such Software. The terms and conditions for
         such use of that Bayer-Software will be negotiated in due time. For the
         avoidance of doubt, software which has been developed solely by Bayer
         will remain the property of Bayer according to Art. 13.5 of the
         Development Agreement.

5.       Good Faith and Man-Power Limitations

         It is understood between LION and Bayer that details of certain
         DELIVERABLES as set forth in ANNEX 2 and ANNEX 5 have not yet been
         specified and fully planned out by LION and its subcontractor. LION and
         Bayer will, in accordance with Section 3 above, jointly specify those
         details in subsequent steps in good faith, and it is understood that
         the technical feasibility may limit the execution of certain
         specifications and the scope of identified DELIVERABLES. The parties
         agree that the generation of the remaining DELIVERABLES must be
         achievable by man-power consisting of a total of 25 full time
         equivalent employees (FTEs) - to be provided by LION and its
         sub-contractor to complete all of the WORK PACKGES within the agreed
         upon time periods during the 19 months following the date of execution
         of this 4/th/ Amendment.

6.       Termination  (Consequences)

         - in context to (S) 15 of the Development Agreement -

         In the case that LION becomes insolvent (Insolvenzverfahren) or winds
         up its business activities (Liquidation) in accordance with (S) 15 (1)
         of the Development Agreement, LION shall take beforehand any necessary
         steps to safeguard Bayer's rights and interest with respect to LION,
         Tripos Inc. and Tripos UK Ltd. by allowing Bayer to assume LION's
         rights and obligations under the corresponding Agreements between LION
         and Tripos Inc. and LION and Tripos UK Ltd.

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7.       Miscellaneous

7.1      The Development Agreement will continue in full force and effect as
         legal, valid and binding obligations of each of the parties subject to
         and as provided in this Agreement (4/th/ Amendment) and earlier
         Amendments as cited in this Agreement - unless amended by this 4/th/
         Amendment - or necessitated by the implementation of this Agreement.

7.2      (S) 18 of the Development Agreement shall apply to this Agreement
         mutatis mutandis.

7.3      The provisions of this Agreement will supersede the corresponding
         provisions of the Development Agreement.

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Executed by and on behalf of LION bioscience AG

Heidelberg, ___________________


/s/ Friedrich von Bohlen und Halbach        /s/ Reinhard Schneider
------------------------------------        ------------------------------
Dr. Friedrich von Bohlen und Halbach        Dr. Reinhard Schneider
CEO                                         CIO



Executed by and on behalf of Bayer AG

Leverkusen, _________________


/s/ J.A. Karlsson                           /s/ W. van den Kerckhoff
------------------------------------        ------------------------------
Dr. J.-A. Karlsson                          Dr. W. van den Kerckhoff
Head of Pharma Research                     Patents and Licenses