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                                                                   EXHIBIT 10.57

CONFIDENTIAL TREATMENT REQUESTED UNDER 17 C.F.R. SECTIONS 200.800(b)(4), 200.83
and 240.24b-2

                             [GENE LOGIC LETTERHEAD]

September 28, 1999

Mr. K. Kiyose
Japan Tobacco Inc.
Pharmaceutical Division
JT Building 2-1, Toranomon 2-chome
Minato-ku, Tokyo 105-8422 Japan

Dear Mr. Kiyose:

As we have discussed, this letter (the "Letter Agreement") will confirm our
agreement regarding certain amendments to the Drug Target and Drug Lead
Discovery Collaboration Agreement between Gene Logic Inc. ("Gene Logic") and
Japan Tobacco Inc. ("JT"), dated as of September 9, 1997 and amended as of
December 29, 1998 (the "Agreement"). This Letter Agreement will be made
effective as of October 1, 1999 upon execution by both Parties. Capitalized
terms used but not otherwise defined in this Letter Agreement shall have the
meanings given such terms in the Agreement.

1.     Section 1.18 of the Agreement shall be amended and restated in its
       entirety as follows:

              "1.18  "GENE LOGIC TECHNOLOGY" shall mean (i) all discoveries,
       inventions, information, data, know-how, trade secrets and materials
       (whether or not patentable) that are Controlled by Gene Logic as of the
       Agreement Date or during the Research Term, including without limitation,
       the Research Databases, GENE EXPRESS(TM) and Gene Logic's READS(TM),
       MuST(TM), microarray and sequencing technologies, excluding the Gene
       Logic Software and any technology related to the Gene Logic Assays, and
       (ii) all Patent Rights of Gene Logic covering the foregoing. All current
       patent applications with respect to GENE EXPRESS(TM) and Gene Logic's
       READS(TM) and MuST(TM) technologies are listed on Schedule 1.18, such
       schedule to be updated by Gene Logic from time to time."

2.     Section 1.36 of the Agreement shall be amended and restated in its
       entirety as follows:

              "1.36  "SAMPLES" shall mean human or animal tissue samples, blood
       samples or cell lines (i) obtained by Gene Logic pursuant to Section 2.5
       or (ii) supplied by JT to Gene Logic for analyses pursuant to the
       Research Plan, if applicable."

3.     The Research Plans shall be amended to include the activities described
       in and contemplated by Section 2.1(d) of the Agreement as set forth in
       Exhibit A to this Letter Agreement.


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4.     Section 2.1 of the Agreement shall be amended to add subsection (d) as
       follows:

                     "(d)   Gene Logic will use 42K GeneChips(R) (the
       "GeneChips") licensed to Gene Logic by Affymetrix, Inc. ("Affymetrix") in
       conducting its activities under the Research Programs in accordance with
       the Research Plans. In addition to amounts payable by JT to Gene Logic
       under Section 7.1, JT will pay Gene Logic [***] per Sample analyzed using
       a single GeneChip set, which payment shall include and cover all costs
       relating to Gene Logic's performance of such analysis, including but not
       limited to the cost of the GeneChip set, Sample preparation, the GeneChip
       assay and data analysis. Such payments by JT for a given quarter shall be
       made in advance, concurrently with the research funding payments
       described in Section 7.2(b), as an FTE-based cost item. Further, should
       Affymetrix's increase its price to Gene Logic for the GeneChips, the
       Parties agree to discuss appropriate price adjustments. The number of
       Samples to be analyzed in a given quarter shall be subject to
       determination in advance by the RMC. For the avoidance of doubt, the
       parties agree that the cost of obtaining Samples shall be separately
       borne and paid by JT in accordance with Section 2.5. All data and progeny
       derived from or generated by Gene Logic's analysis of normal and diseased
       Samples using GeneChips pursuant to the Research Plans, as amended
       (respectively, "Normal Data" and "Disease Data"), shall be disclosed to
       JT pursuant to Section 2.3 hereof. JT shall have the right to use Normal
       Data and Disease Data pursuant to the rights granted to it under Section
       5.1 hereof. During the Research Database Access Term and any Extended
       Term, Gene Logic will have the right to use the Normal Data in its
       GeneExpress databases and/or other databases for licensing or providing
       access to Third Parties and for its own internal research purposes. After
       the Research Database Access Term and any Extended Term, Gene Logic will
       have the right to use the Normal Data and the Disease Data in its
       GeneExpress databases and/or other databases for licensing or providing
       access to Third Parties and for its own internal research purposes. "Raw
       Data", herein defined solely comprising a *.dat file which is generated
       from the electronic scan of a hybridized GeneChip, shall also be
       disclosed to JT pursuant to Section 2.3 hereof. The parties agree that
       they will jointly own the Raw Data which is generated from the GeneChip
       analysis of normal and/or diseased Samples, which they may each use
       without limitation."

5.     Section 4.2 of the Agreement shall be amended and restated in its
       entirety as follows:

              "4.2   OWNERSHIP OF GENE LOGIC TECHNOLOGY, GENE LOGIC SOFTWARE,
       GENE LOGIC ASSAYS AND RESEARCH DATABASES. Notwithstanding the foregoing,
       subject to the grant of rights to JT under Section 5 and except as to Raw
       Data (which is addressed in Section 2.1(d)) and Joint Intellectual
       Property (which is addressed in Section 4.4A), Gene Logic shall own all
       rights to the Gene Logic Technology, Gene Logic Software, Gene Logic
       Assays and the Research Databases, including, but not limited to, all
       data and progeny derived from the Samples, all cDNA sequences, partial
       cDNAs, and their corresponding full length cDNAs, cDNA Sequence Analyses,
       Gene Targets, proteins and applications thereof and information relating
       thereto. The filing, prosecution and maintenance of patent(s), copyrights
       and other proprietary rights directed at the protection of these rights
       shall be the responsibility of, and at the discretion of, Gene Logic."


                                             *  CONFIDENTIAL TREATMENT REQUESTED

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6.     Section 4 of the Agreement shall be amended to add Section 4.4A as
       follows:

              "4.4A  OWNERSHIP OF INTELLECTUAL PROPERTY RIGHTS IN CERTAIN
       INVENTIONS. Gene Logic and JT here agree that Gene Logic and JT shall
       jointly own all rights to Patent Rights and other intellectual property
       rights covering Inventions which are conceived during the Research Term,
       owned by Gene Logic and that arise from Gene Logic's analysis of Samples
       using GeneChips pursuant to the Research Plans, as amended, and that
       relate to Raw Data, Normal Data and/or Disease Data (the "Joint
       Intellectual Property"). Gene Logic hereby makes such assignment of its
       right, title and interest in and to any such Joint Intellectual Property
       as may be necessary to convey to JT joint ownership of such Joint
       Intellectual Property. In cases where Gene Logic does not own such
       Inventions, pursuant to third party agreements existing as of the date
       hereof, Gene Logic shall obtain an exclusive license to Patent Rights and
       other intellectual property rights relating thereto and sublicense such
       Patent Rights and rights to JT on a fully paid up basis. Gene Logic shall
       not during the Research Term and any Extended Term, enter into any
       agreement or understanding with a third party which may limit Gene
       Logic's ability to assign or sublicense such rights to JT as contemplated
       under this Section 4.4A. The filing, prosecution and maintenance of such
       Joint Intellectual Property shall be determined pursuant to Section
       4.5(b). Any such Joint Intellectual Property that covers a Product,
       Biological Therapeutic Product or Diagnostic Product discovered pursuant
       to the Collaboration shall be subject to the applicable provision of
       Section 4.4."

7.     Section 5.1 of the Agreement shall be amended and restated in its
       entirety as follows:

              "5.1   RESEARCH DATABASES, GENE EXPRESS(TM) AND SOFTWARE. Gene
       Logic hereby grants to JT an exclusive, worldwide right to use the
       Research Databases and Disease Data, together with a nonexclusive,
       worldwide right to use GENE EXPRESS(TM) and Normal Data and a
       nonexclusive, worldwide right to use and perform the Gene Logic Software,
       in each case solely for research purposes in the Field to identify Gene
       Targets during the Program Term and for an additional 90 days thereafter
       (such 90-day period shall be referred to as the "Research Database Access
       Term"). JT will have no right to assign such rights to Third Parties and
       shall not provide the Research Databases, the Gene Logic Software or any
       Gene Logic Technology with respect thereto, to any Third Party (other
       than consultants to whom disclosure is permitted under Section 9.3)
       without prior written consent of Gene Logic. JT may elect to extend the
       term of the foregoing exclusive right to the Research Databases and the
       foregoing nonexclusive rights to GENE EXPRESS(TM) and the Gene Logic
       Software (the "Research Database Extension Option") for an additional
       [***] period following the end of the Research Database Access Term (the
       "Extended Term") by providing written notice of such election to Gene
       Logic at least 90 days prior to the date upon which such rights would
       otherwise expire and by paying an extension fee to Gene Logic equal to
       [***] at the time such notice is provided."


                                             *  CONFIDENTIAL TREATMENT REQUESTED
<PAGE>   4

8.     Section 6.1 of the Agreement shall be amended and restated in its
       entirety as follows:

              "6.1   EXPANSION OPTIONS.

       (a)    JT shall have options to expand the Collaboration to include the
       areas of Indication #2 (as such term is defined on Exhibit A attached
       hereto) during the first two years following the Agreement Date (the
       "Indication #2 Option") and Indication #3 (as such term is defined on
       Exhibit A attached hereto) during the first two years plus 60 days
       following the Agreement Date (the "Indication #3 Option") upon the terms
       and conditions contained in this Agreement. If the Research Program with
       respect to Indication #1 is terminated by JT pursuant to Section 2.6
       prior to the exercise or expiration of either Indication #2 Option or
       Indication #3 Option, JT shall inform Gene Logic in writing prior to the
       expiration of the applicable six-month notice period ofwhether or not JT
       will be exercising either or both of such options prior to its expiration
       and if so, when it will exercise such option. In the event that JT does
       not exercise the Indication #2 Option or the Indication #3 Option prior
       to the expiration of the applicable period set forth above or their
       earlier termination as provided in this Section 6.1, then Gene Logic
       shall thereafter be free to grant rights to a Third Party in the areas of
       Indication #2 or Indication #3, as applicable.

              (b)    In addition, JT shall have the option to expand the
       Collaboration to include nonexclusive rights in additional fields (other
       than the Indications) at any time during the period ending six months
       prior to the end of the Research Term upon terms and conditions to be
       negotiated and mutually agreed in good faith by the parties; provided
       that the terms for the expansion shall not be less favorable to JT, when
       viewed in the aggregate, than the terms previously granted by Gene Logic
       to any Third Party for rights of a comparable scope and nature; and
       provided further that the parties agree that the Research Program will
       not include any research program primarily directed toward the discovery
       and characterization of genes associated with the indications listed on
       Schedule 6.1 attached hereto for the purpose of identifying potential
       targets for screening. JT may exercise the option granted under this
       Section 6.1(b) by providing Gene Logic notice of such exercise in writing
       at any time prior to the date that is six months prior to the end of the
       Research Term."

9.     Section 13.11 of the Agreement shall be amended and restated in its
       entirety as follows:

              "13.11 SURVIVAL. Sections 4.1, 4.2, 4.3, 4.4, 4.4A, 9.2, 10, 11.2
       (including the provisions therein that are contemplated to continue
       following termination) 12, 13.1, 13.4 and 13.11 shall survive the
       termination or expiration of this Agreement."

10.    Except as specifically amended by this Letter Agreement, the terms and
       conditions of the Agreement shall remain in full force and effect. This
       Letter Agreement may be executed in two or more counterparts, each of
       which shall be deemed an original, but all of which together shall
       constitute one and the same instrument.


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If the foregoing is acceptable to you, please sign and date this Letter
Agreement in the place indicated below and return it to me via facsimile at
(301) 987-1701. Please feel free to call the undersigned at (301) 987-1700 with
any questions regarding the foregoing.

                                   Sincerely,

                                   GENE LOGIC INC.


                                   By:    /S/ MARK D. GESSLER
                                      -----------------------------------

                                   Name:  Mark D. Gessler
                                        ---------------------------------

                                   Title: President & COO
                                         ---------------------------


Agreed to and accepted:

JAPAN TOBACCO INC.

By:    /S/ TATSUYA YONEYAMA
   ---------------------------------------

Name:  Tatsuya Yoneyama
     -------------------------------------

Title: Vice President, Pharmaceuticals
      ------------------------------------

Date:  Sept. 28   ,1999
     -------------


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                                  SCHEDULE 6.1

                              EXCLUDED INDICATIONS

                                      [***]

                                               *CONFIDENTIAL TREATMENT REQUESTED
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                                    EXHIBIT A
                                  RESEARCH PLAN

                                      [***]


                                               *CONFIDENTIAL TREATMENT REQUESTED