Document:

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EXHIBIT 10.56

                             COLLABORATIVE AGREEMENT

                                     between

                              INCYTE GENOMICS, INC.

                                       and

                           CORVAS INTERNATIONAL, INC.

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                                           *** TEXT OMITTED AND FILED SEPARATELY
                                                CONFIDENTIAL TREATMENT REQUESTED
                                            UNDER 17 C.F.R. SS.SS. 200.80(b)(4),
                                                            200.83 AND 240.24b-2

         This Agreement is entered into as of July 30, 2001 (the "Effective
Date") by and between Corvas International, a Delaware corporation ("Corvas"),
having its principal place of business at 3030 Science Park Road, San Diego, CA
92121, and Incyte Genomics, Inc., a Delaware corporation ("Incyte"), having its
principal place of business at 3160 Porter Drive, Palo Alto, CA 94304.

RECITALS
--------

         WHEREAS, Incyte owns or has rights in certain patent rights and
know-how regarding certain high-throughput partial cDNA sequencing, cloning, and
data analysis technologies; and

         WHEREAS, Incyte has compiled and is compiling, and owns, certain
information and data regarding certain cDNAs in confidential databases which may
be useful in the study of biological phenomena; and

         WHEREAS, Incyte owns or has rights in certain patent rights and
know-how regarding certain cDNAs as well as certain of the proteins they encode;
and

         WHEREAS, Corvas desires to obtain access to Incyte's LifeSeq(R)
Database Product(s) (as defined below), and to obtain licenses to use Incyte's
patent rights and know-how in the Database Products, to conduct research and
development of Drug Products (as defined below);

NOW, THEREFORE, the Parties agree as follows:

1.0      DEFINITIONS.
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The following terms shall have the following meanings:

1.1      "ACCESS TERM": shall mean the period commencing on the Effective Date
         and ending on the date immediately preceding the [...***...]
         anniversary of the Effective Date, unless sooner terminated under
         Section 7.0).

1.2      "ANNOTATION INFORMATION": shall mean the information associated with
         individual cDNAs contained in each and/or all of the LifeSeq(R)Database
         Product(s), as applicable including, but not limited to, Gene
         Expression Profiles, homology information, gene cluster identifiers,
         etc.

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1.3      "ANNUAL REPORTING MECHANISM": shall mean Corvas' obligation, on an
         annual basis, to notify Incyte as to the number of Gene Product(s) Used
         by Corvas during the previous twelve (12) month period and the calendar
         quarter in which such Gene Product was Used by Corvas.

1.4      "ANTISENSE FIELD OF USE": shall mean the treatment or prevention of any
         disease, state or condition in humans by use of one or more
         oligonucleotides or modified oligonucleotides which bind either (i) to
         mRNA to block the translation of mRNA IN VIVO to inhibit, prevent
         and/or alter protein production, or (ii) to DNA to prevent the
         transcription of DNA into the mRNA copy of the gene IN VIVO. The
         Antisense Field of Use does not include the sale or license to third
         parties of Database Information or Gene Product(s) as research tools,
         or the use of Database Information or Gene Product(s) to develop
         database products or services.

1.5      "ANTISENSE PRODUCT(S)": shall mean oligonucleotides or modified
         oligonucleotides derived from or targeted to Gene Product(s) for use in
         the Antisense Field of Use.

1.6      "cDNA": shall mean a complementary DNA copy of messenger RNA.

1.7      "cDNA CLONE": shall mean an individual plasmid vector and cDNA insert,
         which cDNA is usually a partial gene, and not necessarily a full-length
         gene.

1.8      "CORVAS AFFILIATE": shall mean any corporation, firm, partnership, or
         other legal entity, which, directly or indirectly is owned or under
         common ownership by Corvas to the extent of which the common stock or
         other equity ownership thereof is one hundred percent (100%) owned by
         Corvas; provided however, that where local laws require a minimum
         percentage of local ownership, the status of Corvas Affiliate will be
         established if Corvas directly or indirectly owns or controls the
         maximum ownership percentage that may, under such local laws be owned
         or controlled by foreign interests.

1.9      "DATABASE INFORMATION": shall mean all or any part of the Annotation
         Information and DNA Sequence Information which is contained in each
         and/or all of the LifeSeq(R)Database Product(s), as applicable, and the
         Gene Family Dataset.

1.10     "DESIGNATED GENE PRODUCT": shall mean a given Gene Product which is
         selected for research and development, or other use by Corvas in
         accordance with the terms and conditions of this Agreement, and is or
         has been "Used By Corvas", as defined below, during the Access Term.

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1.11     "DNA SEQUENCE INFORMATION": shall mean human nucleotide sequences
         incorporated into the LifeSeq(R) Database Product(s) provided by Incyte
         to Corvas pursuant to this Agreement.

1.12     "DRUG PRODUCT(S)": shall mean any compositions of matter which are
         ligands or inhibitors of Gene Product(s) which are agonists,
         antagonists, and/or modulators of Gene Product(s), for use in the
         treatment or prevention of any disease in humans; provided, however,
         that Drug Product(s) shall not include Therapeutic Protein Products or
         Antisense Products or Substrates of Gene Products.

1.13     "FULL LENGTH CLONE": shall mean, with respect to a given human gene, a
         specific, purified cDNA Clone developed or acquired by Incyte,
         containing the nucleotide sequence of the entire amino acid coding
         region of such human gene.

1.14     "FULL LENGTH CONTIG": shall mean, with respect to a given human gene,
         DNA Sequence Information contained in the LifeSeq(R)Database Product(s)
         which corresponds to the entire amino acid coding region of such human
         gene.

1.15     "GENE EXPRESSION PROFILE(S)": shall mean a listing of cDNAs by name
         with each cDNA assessed by a homology score to be:

                  an exact match to a known gene sequence, or
                  a match to a proprietary Incyte cDNA, or
                  a homolog of a known gene or proprietary Incyte cDNA, or
                  a new clone with no prior identified homology or overlap.

         This profile includes transcript abundance and certain annotation
         information regarding such cDNA derived from Incyte and public
         databases, but does not include DNA Sequence Information.

1.16     "GENE FAMILY DATASET": shall mean a single release of DNA Sequence
         Information and Annotation Information relating to Gene Products that
         are serine proteases, in flat file format, to be mined using Incyte's
         bioinformatic services, from the most current commercially-released
         version of the LifeSeq Database troduct(s) as of the Effective Date (to
         be delivered electronically) using SPSCAN and Incyte Proprietary HMM's
         and delivered by Incyte to Corvas pursuant to Section 2.1.3.

1.17     "GENE PRODUCT(S)": shall mean (i) Incyte's proprietary cDNA Clone(s)
         and Full Length Clones corresponding to a given cDNA in the DNA
         Sequence Information and (ii) any partial cDNAs, DNA sequences, genes,
         and full length cDNAs corresponding to such genes, or any RNA
         sequences, peptides,

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         polypeptides and proteins encoded thereby. Gene Products shall exclude
         Drug Products.

1.18     "INCYTE KNOW-HOW": shall mean the information, software, data and
         biological materials consisting of or directly and solely relating to
         Database Information which are Proprietary to Incyte either at the time
         of disclosure to Corvas or at the time of Use By Corvas and not already
         known to Corvas (with the right to use) independent of the Database
         Information, as can be demonstrated by tangible records of Corvas
         existing prior to such time of disclosure, all to the extent and only
         to the extent that Incyte has the right to grant licenses, immunities
         or other rights to Corvas thereunder; PROVIDED, HOWEVER, that Incyte
         Know-How shall exclude Incyte Patent Rights and all Incyte Proprietary
         Programs; and further provided that genomic DNA sequence information
         which is part of the public domain or was already known to Corvas (with
         the right to use) does not render Database Information non-proprietary
         or non-confidential except to the extent that such genomic DNA sequence
         information has been specifically and materially established as exon
         region(s) (i) via standard molecular biology laboratory including, but
         not limited to, isolation and analysis of cDNA clones (including ESTs),
         5' and 3' RACE, "clone capture", RNA mapping with nuclease S1, mung
         bean nuclease, ribonuclease, or exonuclease VII (including ribonuclease
         protection), and other protocols described in Molecular Cloning, 3rd
         Edition (Sambrook and Russell) or Current Protocols in Molecular
         Biology (Ausubel, et al.). or (ii) through the use of a suitable
         computer algorithm or visual inspection and comparison of genomic DNA
         sequences (including predicted amino acid sequences of putative open
         reading frames or ORF's) with known serine protease genes, cDNAs,
         expressed sequence tags, and amino acid sequences, as can be
         demonstrated by Corvas' tangible records existing prior to the time of
         disclosure of Database Information

1.19     "INCYTE PATENT RIGHTS": shall mean the patents and/or patent
         applications that (i) are owned, or controlled or licensed by Incyte to
         the extent that they claim the composition of matter of Gene Product(s)
         or any other cDNAs identified in the DNA Sequence Information, (ii) are
         related to software or algorithms used by Incyte, and/or (iii) arise
         solely from the generation of Database Information and claim the use of
         Gene Product(s) with respect to Drug Product(s), throughout the world
         as well as reissues, reexaminations, divisionals, provisionals,
         continuations or continuations-in-part thereof or therefor only to the
         extent that they claim, inventions described in (i) or (ii) above, all
         to the extent and only to the extent Incyte has the right to grant
         licenses, immunities or other rights thereunder; PROVIDED, HOWEVER,
         that Incyte Patent Rights shall exclude all patent rights arising under
         Incyte Proprietary Programs

1.20     "INCYTE PROPRIETARY PROGRAM(S)": shall mean an internal research and
         development program of Incyte which involves investment by Incyte
         intended to

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         develop discoveries, inventions, data or information (whether or not
         patentable) beyond that consisting of Database Information. In
         particular, Incyte Proprietary Programs shall include discoveries,
         data, inventions, or information related to antibodies. Incyte
         Proprietary Programs are independent of those services regularly
         performed by Incyte to produce or generate DNA Sequence Information and
         Annotation Information intended to be released to the LifeSeq(R)
         Database Product(s).

1.21     "INCYTE TECHNOLOGY": shall mean, collectively, Incyte Know-How and
         Incyte Patent Rights.

1.22     "KNOWN GENE": shall mean a gene represented in the LifeSeq(R)Gold
         Database, of which [...***...] or more Of the nucleotide sequence
         within the open reading frame of the protein encoding the Serine
         Protease domain region is Known to Corvas.

1.23     "KNOWN TO CORVAS": shall mean information, software, data, biological
         materials and/or other materials disclosed or provided by Incyte to
         Corvas which:

         (a)  is already known to Corvas at the time of disclosure by Incyte; or

         (b)  is generally known to the public or otherwise part of the public
              domain at the time of its disclosure to Corvas; or

         (c)  was subsequently lawfully disclosed to Corvas by a third party,
              provided it was not obtained by such third party directly or
              indirectly from Incyte on a confidential basis; or

         (d)  was independently discovered or developed by Corvas as can be
              documented by laboratory notebooks or other such records as are
              customary for documenting research and product development
              activities created at the time of such independent discovery or
              development.

1.24     "LIFESEQ(R) DATABASE PRODUCT(S)": shall mean Incyte's proprietary
         database of human Annotation InformatioN and DNA Sequence Information
         and corresponding cDNA Clones and Full Length Clones as of the
         Effective Date, and as updated thereafter during the Access Term to
         include additional Annotation Information and/or DNA Sequence
         Information and corresponding cDNA Clones, together with related
         software and documentation, as described generally in Exhibit A.

1.25     "NET SALES": shall mean with respect to each country in the Territory,
         invoiced sales by Corvas, or Affiliates or sublicensees of Corvas on
         all sales of Drug Product (in final form for end use) to an
         unaffiliated third party (whether an end-

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         user, a distributor or otherwise), and exclusive of intercompany
         transfers or sales, less the following deductions from such gross
         amounts which are actually incurred, to the extent that they are
         reasonable and customary amounts for such item in the market in which
         such sale occurred: , and provided that such deductions shall not
         exceed ten percent (10%) of aggregate invoiced sales:

         (a)  credits or allowances actually granted for damaged Drug Products,
              returns or rejections, including recalls of Drug Product and
              retroactive price reductions;

         (b)  freight, postage, shipping, customs duties and insurance charges;

         (c)  normal and customary trade, cash and quantity discounts,
              allowances and credits;

         (d)  sales, value added or similar taxes duties or other governmental
              charges (other than income taxes) levied on, absorbed or otherwise
              imposed on the sale of royalty bearing products measured by the
              billing amount, when included in billing;

         (e)  charge back payments and rebates granted to managed health care
              organizations; or to federal, state and local governments, their
              agencies, and purchasers and reimbursers or to trade customers;

         (f)  commissions paid to third parties other than sales personnel and
              sale representatives or sales agents; and

         (g)  rebates (or equivalents thereof) granted to or charged by
              national, state or local governmental authorities in countries
              other than the United States.

1.26     "PHASE I CLINICAL TRIAL": shall mean that portion of the clinical
         development program which provides for the trials of a specific Drug
         Product on sufficient numbers of healthy volunteers and/or patients to
         establish the safety of such Drug Product in humans to support
         initiation of Phase II Clinical Trials.

1.27     "PHASE II CLINICAL TRIAL": shall mean that portion of the clinical
         development program which provides for the continued trials of a
         specific Drug Product on sufficient numbers of patients to establish
         the safety and appropriate dose of such Drug Product in humans to
         support initiation of Phase III Clinical Trials.

1.28     "PHASE III CLINICAL TRIAL": shall mean that portion of the clinical
         development program which provides for the continued trials of a
         specific Drug Product on sufficient numbers. of patients to establish
         the safety and efficacy of such Drug

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         Product to standard consistent with that necessary to support
         Regulatory Approval required to market and sell the Drug Product for
         the applicable indication(s) in any country in the world.

1.29     "REGULATORY APPROVAL": shall mean, with respect to any country in the
         world, applications or approval of any national, supra-national ,
         regional, state or local regulatory agency, department, bureau,
         commission, council or other governmental entity, necessary for the
         lawful manufacture, distribution, use, import, export or sale of Drug
         Product(s) in such country.

1.30     "RESEARCH FIELD OF USE": shall mean all internal research applications
         of Gene Product(s), associated with conducting research in the
         identification, development and commercialization of Drug Products. The
         Research Field of Use does not include the sale or license of Database
         Information or Gene Product(s) as research tools, or the use of
         Database Information or Gene Product(s) to develop database products or
         services.

1.31     "SUBSTRATE(S)": shall mean an entity that is cleaved or modified by an
         enzyme into one or more products.

1.32     "SERINE PROTEASE(S)": shall mean the Serine Protease Dataset and
         (Chymo)trypsin family serine proteases, which are defined by the
         following structural and mechanistic criteria. Members of this gene
         family exhibit structural homology to trypsin and chymotrypsin. The
         catalytic mechanism of these enzymes involves nucleophilic attack of
         the P1 carbonyl carbon atom of a peptide bond by an active site residue
         and the formation of a covalent acyl-enzyme intermediate. Genes
         identified by Corvas which meet the above criteria but fall outside the
         Serine Protease Dataset shall be noticed in writing, with respect to
         gene identifier, to Incyte at the time of Use by Corvas.

1.33     "SERINE PROTEASE DATASET": shall mean those Gene Product(s) listed by
         template identifier (as may be revised by Incyte) specified in Exhibit
         C and any others identified by Incyte and provided in the
         LifeSeq(R)Gold Database.

1.34     "TERRITORY": shall mean the entire world.

1.35     "THERAPEAUTIC FIELD OF USE": shall mean the treatment or prevention of
         any disease, state or condition in humans by any means, (including
         without limitation, gene therapy), excluding the Antisense Field of
         Use. The Therapeutic Field of Use does not include the sale or license
         of Database Information or Gene Product(s) as research tools, or the
         use of Database Information or Gene Product(s) to develop database
         products or services.

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1.36     "THERAPEUTIC PROTEIN PRODUCT(S)": shall mean any product or service,
         including gene therapy, which uses a protein, peptide or polypeptide
         which is a Gene Product in the treatment or prevention of any disease,
         state or condition in humans, including gene therapy products; provided
         however, that Therapeutic Protein Product(s) does not include Antisense
         Product(s).

1.37     "USED OR USE BY CORVAS": shall mean the first use by Corvas or an
         Affiliate of Corvas of Database Information or a proprietary cDNA Clone
         obtained from Incyte hereunder, in each case which at the time of such
         use is either included in the Incyte Know-How or the Incyte Patent
         Rights, and provided that such first use by Corvas meets any or all of
         the following criteria:

         (a)  Corvas uses such cDNA Clone from the LifeSeq(R) Database
              Product(s) which contains DNA Sequence Information that partially
              or completely codes for a Gene Product in a screening assay to
              identify small molecules and/or antibodies which are antagonists,
              agonists, inverse agonists, and/or modulators of Gene
              Product(s);or

         (b)  Corvas uses such cDNA Clone from the LifeSeq(R) Database
              Product(s) which contains DNA Sequence Information that partially
              or completely codes for a Gene Product to synthesize or have
              synthesized a peptide or polypeptide or protein or oligonucleotide
              and test the efficacy of such Gene Product(s) in an animal disease
              model system; or

         (c)  such Database Information or such cDNA Clone which contains the
              Database Information is disclosed or otherwise transferred to a
              third party including but not limited to consultants and
              collaborators of Corvas; or

         (d)  such Database Information is specifically disclosed in a Corvas
              patent or patent application

         provided, however that if Corvas and/or an Affiliate of Corvas has
         independently discovered, developed and/or acquired from an
         unaffiliated third party (in each case without use of Incyte Technology
         and as documented by Corvas', and/or Corvas' Affiliates, tangible
         records generated at the time of such discovery, development or
         acquisition) Known Gene sequence information and/or other information
         with respect to a specific Gene Product contained in the LifeSeq(R)
         Database Products which is Known to Corvas, then Corvas' and Corvas
         Affiliates' use or disclosure of such independently discovered,
         developed or acquired information shall not constitute "Use By Corvas".

         For the avoidance of doubt, the use of a cDNA Clone or DNA Sequence
         Information by Corvas as an array element on a gene expression
         microarray for internal use by Corvas and its Affiliates shall not
         require establishing such cDNA

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         Clones or DNA Sequence Information as Designated Gene Products unless
         and until the time that the subsequent use of such cDNA Clone or DNA
         Sequence Information would qualify under any of the activities under
         (b) to (d) above.

         For the avoidance of doubt, the use of Database Information contained
         in the LifeSeq(R) Database Product(s) to search for putative homologs
         to a given sequence shall not trigger a license to, or establish such
         DNA Sequence Information as, a Designated Gene Product except and until
         the time that the subsequent use of such DNA Sequence Information would
         qualify under any of the activities under (b) to (d) above.

1.38     "VALID CLAIM": shall mean a claim of an issued and unexpired Incyte
         Patent Right which has not been held unenforceable, unpatentable or
         invalid by a decision of a court or governmental body of competent
         jurisdiction, unappealable or unappealed within the time allowed for
         appeal, which has not been lost through an interference proceeding
         which, but for the license granted by Incyte to Corvas, would be
         infringed by the use, manufacture or sale of a Drug Product.

2.0  DATABASE ACCESS.
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2.1      ACCESS TO THE LIFESEQ(R)DATABASE PRODUCT(S).

         2.1.1 ACCESS GRANT. Incyte hereby agrees to provide Corvas with access
         to the Incyte Database Product(s) solely in accordance with the terms
         and conditions of this Agreement. Up to [...***...] identified CorvaS
         employees (specified in Exhibit B) or their alternates as mutually
         agreed upon by Incyte and Corvas (consent by Incyte not to be
         unreasonably withheld), all of whom will be located at Corvas
         facilities at the address first written above, will have access to the
         Incyte Database Products via on-line services over the Internet. Corvas
         will comply with such security procedures, including the use of
         confidential passwords assigned on an individual basis to each Corvas
         employee who will have access to the Incyte Database Products as Incyte
         may reasonably specify to maintain the security of the Incyte Database
         Products, the confidentiality of the Database Information and the
         limitations described in this Agreement with respect to Corvas' use and
         disclosure of Database Information.

         2.1.2 UPDATED RELEASES AND UPDATES. During the Access Term, Incyte
         shall provide Corvas with on-line access data updates of newly released
         Database Information, and such updated releases of the LifeSeq(R)
         Database Product(s), as Incyte provides generally to its LifeSeq
         Database Product collaborators.

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         2.1.3 GENE FAMILY DATASET. Within fifteen (15) days after the Effective
         Date, Incyte shall deliver to Corvas a copy of the Gene Family Dataset.

2.2      USE RESTRICTIONS AND SECURITY REQUIREMENTS

         2.2.1 OWNERSHIP. Corvas hereby acknowledges that (a) Incyte has
         expended significant resources and efforts to develop the
         LifeSeq(R)Database Product(s) and the Database Information, (b) the
         LifeSeq(R)Database Product(s) and the Gene Family Dataset represent
         highly valuable and confidential assets, (c) Incyte is willing to grant
         Corvas access to the LifeSeq(R)Database Product(s) and the Gene Family
         Dataset in reliance upon the agreement by Corvas that it shall protect
         the LifeSeq(R)Database Product(s) and the Gene Family Dataset from
         unauthorized disclosure or use, and (d) the LifeSeq(R)Database
         Product(s) and the Gene Family Dataset at all times during the term of
         this Agreement shall remain the sole and exclusive property of Incyte.

         2.2.2 PERMITTED USE.

               (a) During the Access Term, Corvas shall have the right to use
               the LifeSeq(R) Database Product(s) and the GenE Family Dataset
               solely for its own internal use by authorized personnel of Corvas
               in the Research Field of Use in secure work facilities of Corvas
               in accordance with the terms and conditions of this Agreement.

               (b) Corvas shall not disclose or transfer Database Information
               which would constitute Incyte Know-How, or any portion thereof,
               to any third party, except for Database Information and
               corresponding cDNA Clone(s) specifically regarding a Designated
               Gene Product and in each event solely in accordance with the
               provisions of Sections 2.2.2(c), 2.2.3 and 5.0.

               (c) Solely for purposes of system integration and/or to
               facilitate data analysis and relational analysis (e.g. extraction
               of DNA Sequence Information for homology analysis by Corvas
               search algorithms), Corvas shall have the right to reproduce,
               adapt, modify and prepare derivative works based upon the
               Database Information ("Modifications") solely for internal use by
               Corvas in its research and development programs. Modifications
               shall be kept in confidence in the same manner as, and shall be
               subject to the same terms and conditions as apply to, the
               Database Information. Incyte shall have no obligations to support
               any such Modifications. Corvas shall not acquire by reason of
               this subsection (c) any ownership of any LifeSeq(R)Database
               Product(s), the Gene Family Dataset, any portions thereof or any
               title or rights therein. Corvas shall

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               not distribute copies of, or provide access to, any Modifications
               to any third party without the prior written approval of Incyte.

               (d) Except as expressly set forth herein, or as otherwise agreed
               by Incyte in writing, Corvas shall not reproduce, adapt, modify,
               prepare derivative works based upon, or distribute copies of (in
               whatever form whether tangible or intangible, by any means
               whatsoever whether now known or hereafter invented), the
               LifeSeq(R) Database Product(s) or the Gene Family Dataset,
               including any substantial portion of the Database Information
               from any field of the database.

               (e) Corvas shall have the right to use, disclose and transfer
               Database Information specifically regarding a Gene Product,
               including to Affiliates of Corvas, academic and third party
               collaborators, licensees, governmental agencies or offices or
               otherwise solely for use in the discovery, research, development
               and/or commercialization of Drug Products, subject to the
               appropriate terms and conditions of this Agreement, including
               Article 5.0. Any use of Database Information not in accordance
               with the above is expressly prohibited.

         2.2.3 DESIGNATED GENE PRODUCT(S). During the Access Term and pursuant
         to the Annual Reporting Mechanism, Corvas shall have the right to use,
         disclose and transfer Datatabase Information specifically regarding a
         Designated Gene Product, including the Affiliates of Corvas, academic
         and third party collaborators, licensees, governmental agencies or
         offices or otherwise solely for use in the discovery, research,
         development and/or commercialization of Drug Products, subject to the
         appropriate terms and conditions of this Agreement, including Article
         5.0. Any use of Database Information not in accordance with the above
         is expressly prohibited.

         2.2.4 RECORDS. Corvas shall maintain records of access to and use of
         the LifeSeq(R)Database Product(s), the Gene Family Dataset and the
         Database Information, sufficient to enable Corvas and Incyte to
         determine, and monitor compliance with their respective rights and
         obligations under this Agreement (e.g. laboratory notebooks and such
         other records as are customary for documenting research and product
         development activities). No more than once a year unless as otherwise
         agreed in writing, at the request and the expense of Incyte, upon at
         least forty-five (45) days' prior notice, Corvas shall permit an agent
         appointed by Incyte and acceptable to Corvas to examine these records
         solely to the extent necessary to verify the fulfillment of Corvas'
         obligations under this Agreement, provided that such agent has entered
         into a suitable confidentiality agreement with Corvas. Incyte's agent
         shall only report to Incyte the results of such examination (i.e.,
         whether or not Corvas is in compliance with its obligations under this
         Agreement), and shall not disclose to Incyte any of Corvas'

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         Confidential Information provided to it or to which it may have access
         during the conduct of the examination.

         2.2.5 LOSS, THEFT, UNAUTHORIZED DISCLOSURE OR USE. Corvas promptly
         shall notify Incyte of a loss, theft or unauthorized disclosure or use
         of the Database Information which comes to Corvas' attention.

         2.2.6 TERMINATION OF THE ACCESS TERM. Upon termination or expiration of
         the Access Term with respect to the applicable LifeSeq(R) Database
         Product(s), Corvas, at its election:

               (a) shall have the option of extending the term of such
               LifeSeq(R) Database Product(s) subscription or individual
               database module thereof under terms demonstrably consistent with
               and comparable to those secured by comparable users of the
               LifeSeq(R) Database Product(s) at the time of extension or under
               terms to be mutually agreed to by Corvas and Incyte at the time
               of extension; or

               (b) shall discontinue use of such LifeSeq(R) Database Product(s)
               and Database Information, and promptly return to Incyte, or upon
               Incyte's written instruction destroy, all portions and copies of
               such LifeSeq(R) Database Product(s) and the Database Information;
               except for that certain Database Information specific to
               Designated Gene Product(s) which are the subject of one or more
               of the licenses granted to Corvas under Article 3.0 below.

         Corvas agrees to perform with Incyte a mutually acceptable final
         accounting of those Designated Gene Product(s) which are subject to one
         or more of the licenses granted to Corvas under Article 3.0 below.

         2.2.7 NOTIFICATION OF CLINICAL DEVELOPMENT. Corvas agrees to keep
         Incyte reasonably informed of all Drug Product(s) resulting from the
         use of the LifeSeq(R) Database Product(s) or the Gene Family Dataset,
         including notification when a given Drug Product candidate has been
         designated for clinical development according to appropriate Corvas
         procedures. All information provided by Corvas to Incyte pursuant to
         this Section 2.2.7 shall be treated as Corvas' Confidential
         Information.

2.3      TRAINING.

         2.3.1 At times mutually acceptable to Incyte and Corvas, Incyte shall
         provide Corvas with two (2) days of training services at Incyte's
         training facility in Palo Alto, California, regarding the use of the
         LifeSeq(R) Database Product(s). Corvas may designate not more than
         [...***...] employees to attend each SuCH training at

                                     Page 13   *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

         Incyte, or such other number as mutually agreed. Each party shall bear
         all accrued and out-of-pocket expenses of its own employees in
         connection therewith.

         2.3.2 At times mutually acceptable to Incyte and Corvas, Incyte shall
         provide Corvas with two (2) days of training services at the Corvas'
         facilities, regarding the use of the LifeSeq(R) Database Product(s).
         ThE number of employees to receive such training shall be in the
         reasonable discretion of Corvas. Each party shall bear all accrued and
         out-of-pocket expenses of its own employees in connection therewith.

         2.3.3 Incyte shall provide Corvas with such additional training
         services at times to be agreed upon by Corvas and Incyte at Incyte's
         facilities. Corvas shall pay Incyte [...***...] per Corvas employee
         attending such training and shall be responsible for bearing the
         travel-related expenses of any such Corvas employee attending training
         at Incyte facilities.

3.0 LICENSE GRANTS.
--- ---------------

3.1      NON-EXCLUSIVE LICENSE UNDER INCYTE TECHNOLOGY--RESEARCH

         3.1.1 SERINE PROTEASE(S). During the Access Term, Incyte hereby grants
         to Corvas a worldwide, non-exclusive license (with a right to
         sublicense as provided in Section 3.3 and publish and disclose as
         provided in Section 5.2)) under the Incyte Technology to conduct
         research with respect to Gene Product(s) in the Research Field of Use
         and to discover, develop, make, have made, use, offer to sell, sell,
         import, and distribute Drug Product(s): provided however, that with
         respect to the Research Field of Use such grant does not include the
         right to sell Gene Product(s). The first [...***...] such licenses
         shall be included in the Access Fee provided for in Section 4.1. In the
         event that Corvas purchases [...***...] in products or services from
         Incyte within [...***...] of the Effective Date, the number of such
         licenses included in the Access Fees specified in Section 4.1 shall be
         the first [...***...]. Any additional licenses shall be provided by
         Incyte to Corvas for [...***...] per Gene Product. The term of any
         license specified in this Section 3.1.1 is provided for in Section 7.2.

         3.1.2 NON-SERINE PROTEASE(S). During the Access Term and [...***...],
         Incyte hereby grants to Corvas a worldwide, non-exclusive license (with
         a right to sublicense as provided in Section 3.3, and publish and
         disclose as provided in Section 5.2)) under the Incyte Technology to
         conduct research and development activities with respect to Gene
         Product(s) in the Research Field of Use and to discover, develop, make,
         have made, use, offer to sell, sell, import, and distribute Drug
         Product(s): provided

                                     Page 14   *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

         however, that with respect to the Research Field of Use such grant does
         not include the right to sell Gene Product(s). The term of any license
         specified in this Section 3.1.2 is provided for in Section 7.2.

3.2      RESERVATION OF RIGHTS.

         (a) Incyte reserves the right under the Incyte Technology (i) to
         satisfy its obligations under this Agreement, (ii) to discover,
         develop, make, have made, use and sell Gene Products, Drug Products,
         Therapeutic Protein Products, and Antisense Products in all fields of
         use, and (iii) to grant licenses to third parties to discover, develop,
         make and use and sell Gene Products, Drug Products, Therapeutic Protein
         Products, and Antisense Products in all fields of use.

         (b) With respect to any proprietary cDNA Clone provided to Corvas under
         Section 3.4, Incyte reserves the right under the Incyte Technology at
         any time to (a) release such cDNA Clone to an Incyte database made
         available to collaborators by Incyte on a nonexclusive basis, and/or
         (b) to provide such cDNA Clone to any third party.

3.3      SUBLICENSING.

         3.3.1 On a Gene Product-by-Gene Product basis, Corvas may sublicense to
         any third party, the rights to Designated Gene Product(s) and the
         Incyte Technology relating thereto granted under this Article 3.0 to
         the extent necessary in order to permit the third party to develop,
         make, have made, use, offer to sell, sell, transfer, import, export and
         distribute Drug Product(s) as appropriate according to the role
         assigned to that third party by Corvas' plan for the commercialization
         of such Drug Product(s); PROVIDED, HOWEVER, that without the prior
         written consent of Incyte, no sublicense of Incyte Technology will be
         granted to any third party in the absence of [...***...], and (ii) the
         license or sublicense of patent rights, if any, pertaining thereto,
         owned by, licensed to or controlled by Corvas; and further provided
         that each sublicense has a grant which is consistent with the terms
         herein and that Corvas shall be responsible for payments and royalties
         due to Incyte under Article 4.0. Corvas shall obtain the written
         commitment of any sublicensee to abide by all applicable terms and
         conditions of this Agreement. Promptly upon execution of any
         sublicense, Corvas shall provide notice thereof to Incyte and
         reasonable satisfactory evidence that such sublicense is in compliance
         with this Section 3.3, and shall within thirty (30) days of execution
         of such sublicense remit to Incyte a sublicense fee [...***...] for
         each Designated Gene Product so sublicensed.

                                     Page 15   *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

         3.3.2 No grant of right to sublicense rights to Database Information,
         Designated Gene Product(s) and the Incyte Technology relating thereto
         in the Research Field of Use in order to discover or research Drug
         Products, Antisense Products and Therapeutic Protein Products is
         provided by Incyte to Corvas herein.

3.4      SUPPLY OF cDNA CLONES. Upon the written request of Corvas and subject
         to the grant of license rights as described in Section 3.1, Incyte
         shall provide to Corvas, one or more isolated cDNA Clones from the
         LifeSeq(R) Database Product(s) under the following terms and
         conditions:

         Shipments usually occur within twelve (12) business days of the receipt
         of the order. For this service, a fee of [...***...] verified cDNA
         Clone that is not a Full-Length Clone, and [...***...] per sequence
         verified cDNA Clone that is a Full-Length Clone, will be payable. If
         the cDNA Clone cannot be verified, there is no charge and Corvas may
         request an alternative clone, or request failure analysis on the CDNA
         Clone at a cost of [...***...] per clone. In failure analysis Incyte
         will review the clone retrieval process to determine the failure point
         and proceed to re-process, including searching an entire 96-well plate
         in the case of gel tracking error or electroporating from master
         archives if the clone will not transform. There is no refund of the
         failure analysis fee if Incyte remains unsuccessful in obtaining a
         verified clone..

         Corvas agrees to submit any payments due within thirty (30) days from
         receipt of invoice from Incyte in reasonably detailed form regarding
         such clone supply.

         Corvas agrees that such cDNA Clone(s) are provided to Corvas on a
         nonexclusive basis and subject to any license(s) granted under Article
         3.0.

3.5      NO IMPLIED LICENSES. No implied right or license is granted to Corvas
         to utilize the Incyte Technology in a manner not expressly included
         within the scope of the licenses granted pursuant to this Agreement.
         Other than as expressly granted herein, no licenses either by estoppel,
         implication or otherwise are granted herein. No grant or license to
         Corvas under Incyte Technology is provided under this Article 3.0 with
         respect to any Gene Product which has not been licensed by Corvas
         pursuant to this Agreement (e.g. a Gene Product which is NOT a
         Designated Gene Product).

4.0 SCHEDULE OF PAYMENTS; ROYALTIES.
--- -------------------------------

4.1      ACCESS FEE(S).

                                     Page 16   *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

         Corvas will pay to Incyte a fee for access to the LifeSeq(R) Database
         Product(s) subscription ("Access Fee") of [...***...] each twelve (12)
         month period during the Access Term. The Access Fee shall be payable
         quarterly, with the first such payment due within ten (10) business
         days of the Effective Date. In addition, Corvas will pay to Incyte a
         one-time fee of [...***...] for the right to receive the Gene Family
         Dataset, which will be payable within ten (10) business days following
         Corvas' receipt of the Gene Family Dataset. Of the Access Fee, Corvas
         agrees that [...***...] of the Access Fee will be allocated to any CDs
         delivered by Incyte to Corvas, and [...***...] of the Access Fee will
         be allocated to any user manuals delivered by Incyte to Corvas.

4.2      MILESTONE PAYMENTS AND ROYALTIES.

         4.2.1 Milestone Payments and Royalties. Contingent on the each of the
         events described below, the following payments and royalties shall be
         paid by Corvas (within thirty (30) days of such event, except for
         royalty payments, which are payable pursuant to Section 4.5) to Incyte
         for each Drug Product(s) with respect to Designated Gene Products under
         respective license(s) as applicable:
<TABLE>
<CAPTION>

                                          TABLE 4.2.1
         --------------------------------------- ------------------------- -------------------------
                                                     Agreement as of              Expansion
                                                      Effective Date                Option
         --------------------------------------- ------------------------- -------------------------
<S>                                              <C>                       <C>
                                                      Non-Exclusive             Non-Exclusive
                                                     License(s) under          License(s) under
                                                          Incyte                    Incyte
                                                       Technology -              Technology -
                                                       Drug Product              Drug Product

                                                      (Section 3.1)             (Section 3.1)
         --------------------------------------- ------------------------- -------------------------
            # of Designated Gene Product(s)         [...***...] within        [...***...] within
                                                          Serine                    Serine
                                                       Protease(s)               Protease(s)
         --------------------------------------- ------------------------- -------------------------
                      Upgrade Fee                           0                    [...***...]

                                                                                See (g) below
         --------------------------------------- ------------------------- -------------------------
                   Annual Access Fee                   [...***...]               [...***...]
         --------------------------------------- ------------------------- -------------------------
                      [...***...]                      [...***...]               [...***...]
         --------------------------------------- ------------------------- -------------------------

                                            Page 17                *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

         --------------------------------------- ------------------------- -------------------------
                      [...***...]                      [...***...]               [...***...]
         --------------------------------------- ------------------------- -------------------------
         --------------------------------------- ------------------------- -------------------------
                      [...***...]                      [...***...]               [...***...]
         --------------------------------------- ------------------------- -------------------------
         --------------------------------------- ------------------------- -------------------------
                      [...***...]                      [...***...]               [...***...]
         --------------------------------------- ------------------------- -------------------------
         --------------------------------------- ------------------------- -------------------------
                      [...***...]                      [...***...]               [...***...]
         --------------------------------------- ------------------------- -------------------------
         --------------------------------------- ------------------------- -------------------------
                                                       [...***...]               [...***...]

                Royalties on Net Sales
                     See (i) below                     [...***...]               [...***...]
         --------------------------------------- ------------------------- -------------------------
         Notes: All fees, payments, and royalties are to be made in United States dollars.
         [...***...]
         [...***...]
         [...***...]
         [...***...]
         [...***...]
         [...***...]
</TABLE>

         (g)      Corvas shall hove the right during the Access Term or any
                  extensions thereof to upgrade the current access program to
                  Expanded Option specified in Table 4.2 above. The option to
                  upgrade must be exercised by [...***...]. An upgrade fee of
                  [...***...] apply. The values in each of the options will be
                  replaced and amended to the current contact. All other terms
                  within contract will apply.
         [...***...]
         [...***...] into a sublicense agreement with a third party who is also
         subscriber of the LifeSeq Database Product, the Royalties on Net Sales
         shall be [...***...].

                                     Page 18   *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

         4.2.2 ROYALTY-RATE REDUCTION. Corvas shall have the right to reduce
         royalty rates on Net Sales of all licensed Gene Products upon payment
         of a one-time fee as set forth in Table 4.2.2. Reduction of royalties
         can be exercised [...***...]. The royalty rates in the selected option
         will be replaced and amended in the Agreement. All other terms in the
         Agreement will remain in full force and effect.
<TABLE>
<CAPTION>
<S>                 <C>                           <C>                            <C>
                                                        TABLE 4.2.2
------------------ ------------------------------ ------------------------------ ------------------------------
    ROYALTIES                  OPTION 1                       OPTION 2                       OPTION 3
  PAYABLE ON       ------------------------------ ------------------------------ ------------------------------
      NET            [...***...]    [...***...]     [...***...]    [...***...]     [...***...]    [...***...]
------------------ ------------------------------ ------------------------------ ------------------------------
  [...***...]                [...***...]                    [...***...]                    [...***...]
------------------ ------------------------------ ------------------------------ ------------------------------
  [...***...]                [...***...]                    [...***...]                    [...***...]
------------------ ------------------------------ ------------------------------ ------------------------------
  [...***...]                [...***...]                    [...***...]                    [...***...]
------------------ ------------------------------ ------------------------------ ------------------------------

</TABLE>

4.3      PAYMENT OBLIGATION. The foregoing payments under Section 4.2 will
         accrue or become due or payable with respect to Drug Product(s) which
         are:

                  (a) materially based on, or use materially or are directly
                  derived by material use of that which would constitute Incyte
                  Know-How at the time of Use By Corvas; or

                  (b) are covered by a Valid Claim of Incyte Patent Rights
                  and/or which Drug Product is identified; or

                  (c) discovered by a drug discovery process (e.g. compound
                  screening) which utilizes a Designated Gene Product which is
                  covered by a Valid Claim of Incyte Patent Rights.

                                    Page 19    *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

         If a Drug Product would be covered by more than one of the licenses
         referred to in Section 4.2 (e.g., where a Drug Product is covered by
         two or more of the Designated Gene Product Licenses granted to Corvas
         under Section 3.1), only the [...***...] and there will be no multiple
         royalties due under such Section 4.2.

4.4      DURATION OF PAYMENT OBLIGATION. Royalty obligations payable with
         respect to each Drug Product under a Valid Claim of Incyte Patent
         Rights shall terminate on a country-by-country and product-by-product
         basis on the [...***...] of [...***...] after the first country-wide
         launch of each Drug Product in each country or (ii) expiration or
         invalidation of the last-to expire Valid Claim which covers such
         product in each country. Royalty obligations payable with respect to
         each Drug Product under Incyte Know-How shall terminate on a
         country-by-country and product-by-product basis [...***...] after the
         first country-wide launch of each Drug Product in each country.

         Upon termination of the royalty payment obligation, Corvas shall
         thereafter have in perpetuity a royalty-free license to make, use and
         sell such Drug Product in the specified field(s) of use without any
         accounting to Incyte.

4.5      MODE OF PAYMENT. For purposes of determining when a sale of a
         royalty-bearing Drug Product occurs, the sale shall be deemed to occur
         on the date of the invoice to the purchaser of the Drug Product. All
         royalty payments shall be made within ninety (90) days of the end of
         each calendar quarter in which the sale was made. Any royalty payment
         that is not paid on or before the date such payment is due under this
         Agreement shall bear interest to the extent permitted by applicable
         law, at two percentage points over the prime rate of interest as
         reported by Bank of America NT&SA in San Francisco, California, from
         time to time, for the number of days such payment is delinquent.
         Royalties shall be deemed payable by the entity making the Net Sales
         and subject to foreign exchange regulations then prevailing. Royalty
         payments shall be made to Incyte in United States dollars. The rate of
         exchange to be used in any such conversion from the currency in the
         country where such Net Sales are made shall be the rate of exchange
         used by Corvas for reporting such sales for United States financial
         statement purposes.

4.6      RECORDS RETENTION. Corvas agrees to keep for at least three (3) years'
         records of all sales of Drug Products in sufficient detail to permit
         Incyte to confirm the accuracy of Corvas' royalty calculations. Once a
         year, at the request and the expense of Incyte, upon at least
         forty-five (45) days' prior written notice, Corvas shall permit a
         nationally recognized, independent, certified public accountant

                                    Page 20    *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

         appointed by Incyte and acceptable to Corvas, to examine these records
         solely to the extent necessary to verify such calculations, provided
         that such accountant has entered into a confidentiality agreement with
         Corvas substantially similar to the confidentiality provisions of this
         agreement, limiting the use and disclosure of such information to
         purposes germane hereto. The examination shall be limited to pertinent
         books and records for any year ending not more than twenty-four (24)
         months prior to the date of such request. Corvas may designate
         competitively sensitive information which such auditor may not disclose
         to Incyte, PROVIDED, HOWEVER, that such designation shall not encompass
         the auditor's conclusions. The accounting firm shall disclose to Incyte
         only whether the royalty reports are correct or incorrect and the
         specific details concerning any discrepancies. No other information
         shall be provided to Incyte. If such accounting firm correctly
         concludes that there was an underpayment of royalties by [...***...] or
         more, Corvas shall pay all costs of such examination. If such
         accounting firm concludes that additional royalties were owed, the
         additional royalties shall be paid within thirty (30) days of the date
         Incyte delivers to Corvas such accountant's written report. Any
         overpayments by Corvas will be credited against future royalty
         obligations. This section shall survive the cessation of payment
         obligations under Section 4.3 for a period of two (2) years.

4.7      SHIPPING. Corvas shall pay, for its own account, any shipping, freight,
         mailing expenses and the like payable to third parties not affiliated
         with Incyte and arising out of obtaining tangible materials under this
         Agreement and the transactions contemplated herein.

4.8      PAYMENTS AND TAXES. Unless otherwise provided in this Agreement, Corvas
         agrees to submit payments within thirty (30) days from receipt of
         invoice. All payments hereunder shall be in United States dollars and
         shall be made by bank wire transfer in immediately available funds to
         such account as Incyte shall designate in writing from time to time.
         All payments by Corvas to Incyte under this Agreement shall be paid
         from a Corvas account in a banking institution located in the United
         States.

         Corvas shall pay, or reimburse Incyte, as appropriate, and indemnify
         Incyte against any sales, use, value added/ad valorem, surtax and
         personal property taxes, customs duties, registration fees and the like
         including interest and penalties arising out of this Agreement and
         transactions contemplated herein and including the costs and
         responsibility of any withholding taxes. Corvas shall make any
         withholding payments due on behalf of Incyte, and shall promptly
         provide Incyte with written documentation of any such payment made on
         behalf of Incyte sufficient to satisfy any requirements of the United
         States Internal Revenue Service, or foreign government, as applicable,
         related to an application by Incyte for a foreign tax credit or refund
         for such payment to the extent

                                    Page 21    *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

         applicable; provided however that in the case where Incyte can take and
         receives a credit or refund against its United States tax liability for
         the withholding payments due on behalf of Incyte and made by Corvas,
         then such credited or refunded withholding payment will be reimbursed
         by Incyte or deducted by Corvas as appropriate. The Parties agree to
         take reasonable and lawful steps to minimize the amount of tax to which
         payments to Incyte are subject.

5.0 CONFIDENTIALITY AND PUBLICATION.
--- -------------------------------

5.1      CONFIDENTIALITY. The Parties acknowledge that during the course of this
         Agreement they will each receive from the other information, which is
         proprietary, confidential and of commercial value to the disclosing
         Party. For purposes of this Agreement, "CONFIDENTIAL INFORMATION" shall
         mean scientific, technical or business information belonging to the
         disclosing Party, which the disclosing Party marks "Confidential" if
         disclosed in writing, or which the disclosing Party identifies as
         confidential at the time of any visual or oral disclosure and promptly
         confirms in writing to have been confidential. Except to the extent
         expressly authorized by this Agreement, the Parties agree that, for the
         Access Term and for five (5) years thereafter, the receiving Party
         shall keep confidential and shall not publish or otherwise disclose and
         shall not use for any purpose (except those expressly permitted under
         this Agreement) any Confidential Information furnished to it by the
         other Party pursuant to this Agreement, and regardless of the medium on
         which it is provided, including know-how, except to the extent that it
         can be established by the receiving Party by competent proof that such
         information:

                  (a) was already known to the receiving Party, other than under
                  an obligation of confidentiality, at the time of disclosure by
                  the other Party;

                  (b) was generally known to the public or otherwise part of the
                  public domain at the time of its disclosure to the receiving
                  Party;

                  (c) became generally available to the public or otherwise part
                  of the public domain after its disclosure other than through
                  any act or omission of the receiving Party in breach of this
                  Agreement;

                  (d) was subsequently lawfully disclosed to the receiving Party
                  by a third party having no confidentiality obligations to the
                  disclosing Party with respect thereto;

                  (e) was independently discovered or developed by the receiving
                  Party without the use of the other Party's Confidential
                  Information, and such independent discovery or development can
                  be documented by the

                                    Page 22
<PAGE>

                  receiving Party's tangible records created at the time of such
                  independent development.

         Each Party may disclose the other's Confidential Information to the
         extent such disclosure is reasonably necessary in (i) filing and
         prosecuting patent applications, and maintaining patents, or (ii)
         prosecuting or defending litigation or (iii) complying with applicable
         governmental laws and regulations governing the testing approval,
         manufacture and marketing of Drug Products; provided, however, that
         prior to disclosure of the other Party's Confidential Information it
         will give reasonable advance notice to such Party, will only disclose
         the minimum Confidential Information necessary, and will use reasonable
         efforts to secure confidential treatment of such Confidential
         Information.

                  It is understood that patent applications are filed with the
         expectation and intention that such applications will, upon publication
         of the applications and/or issuance of the resulting patents, result in
         the publication or public accessibility of all information disclosed in
         the underlying application and prosecution documents; provided,
         however, that publication of such Information shall not affect either
         Party's ongoing' obligations to the other Party with respect to
         Information not so disclosed.

5.2      DISCLOSURE AND PUBLICATION. Except as provided for in Sections 2.2.3
         and 3.3 above and by this Section 5.2 Confidential Information of
         Incyte will not be published or disclosed in any form without the
         written authorization of Incyte.

         (a) Corvas, Corvas Affiliate(s) and its sub licensees may publish their
         own scientific results and the conduct of their work within the scope
         of the licenses granted under this Agreement, provided, however, that:

                  (i) any such publication by Corvas, its Affiliates or
                  sublicensees that would disclose Confidential Information of
                  Incyte shall require the prior written consent of Incyte,
                  which consent will not be unreasonably withheld or delayed and
                  such consent or denial of consent shall be provided to Corvas
                  within thirty (30) days of Incyte receiving request from
                  Corvas, provided that Corvas has given Incyte a copy of each
                  such publication for diligent review at least thirty (30) days
                  prior to its submission for publication; and

                  (ii) such disclosure is on an individual Gene Product-by-Gene
                  Product-basis, is related specifically to selection of
                  Designated Gene Product(s) and reflects research results which
                  have involved material investment above and beyond Database
                  Information; and

                                    Page 23
<PAGE>

                  (iii) Corvas has notified Incyte in accordance with the Annual
                  Reporting Mechanism ; and

                  (iv) Incyte has had the opportunity to file applications for
                  protection of subject matter that is proprietary to Incyte;
                  and

                  (v) any such publications will include recognition of the
                  contributions of Incyte according to standard practice for
                  assigning scientific credit, either through authorship or
                  acknowledgment as may be appropriate.

         (b) Any scientific publications that would disclose Confidential
         Information of Incyte on other than an individual Designated Gene
         Product by Gene Product basis shall be under reasonable terms and
         conditions mutually agreed between the Parties, including the
         provisions of subparagraphs 5.2(a) (i), (iii) and (iv) above.

         (c) Incyte recognizes that Corvas, in the normal course of business,
         utilizes consultants, academic and third party collaborators who are
         bound by a contractual obligation to Corvas, including an obligation of
         confidentiality to Corvas. Corvas may disclose Confidential Information
         of Incyte to such consultants and academic and third party
         collaborators in the context of the disclosure of Corvas' own
         scientific results or the conduct of its work within the scope of the
         licenses granted herein, provided, however, that:

                  (i) Corvas has obtained a written obligation of
                  confidentiality and appropriate use restrictions no less
                  restrictive than those set forth herein and provided that such
                  third party shall not further disclose Confidential
                  Information; and

                  (ii) any such disclosure of Confidential Information which
                  includes the transfer of DNA Sequence Information or
                  biological materials shall be subject to a written materials
                  transfer agreement which protects the intellectual property
                  rights of Incyte and Corvas as set forth herein, such
                  agreement to include customary provisions regarding scope of
                  work, publication, protection of proprietary subject matter
                  and ownership of inventions; and

                  (iii) Corvas has notified Incyte in accordance with the Annual
                  Reporting Mechanism; and

                                    Page 24
<PAGE>

                  (iv) Corvas has obtained a written obligation from such third
                  party regarding Corvas' right to review publications which are
                  at least as restrictive as the provisions of Section 5.2(a)
                  herein.

         d). With respect to the transfer of DNA Sequence Information or
         biological materials on other than an individual Gene Product basis,
         the provisions of Sections 5.2(c) sub-paragraphs (i) to (iv) above
         shall apply and Collaborator agrees to obtain the prior written consent
         of Incyte with respect to such third party transfer, and Incyte retains
         the right to review and approve the relevant sections of the written
         materials transfer agreement between Collaborator and such third party,
         with such consent and approval not to be unreasonably withheld

         e) Incyte shall not publish or disclose any of Corvas' Confidential
         Information without the prior written consent of Corvas.

5.3      Notwithstanding anything to the contrary set forth herein, this Article
         5.0 shall not be construed to allow Corvas, its Affiliates,
         sublicensees, collaborators or consultants to publish or disclose the
         contents of LifeSeq(R) Database Product(s), or any Incyte software or
         hardware configurations, at any time without the express written
         consent of Incyte.

6.0 INTELLECTUAL PROPERTY.
--- ---------------------

6.1      INCYTE RIGHTS. With the exception of intellectual property rights
         granted to Corvas under the nonexclusive or exclusive license(s)
         granted under this Agreement, Incyte retains all rights it has to the
         Incyte Technology, Database Information and the LifeSeq(R) Database
         Product(s) and no licenses are granted herein except for those
         expressly provided in Article 3.0 .

6.2      CORVAS RIGHTS. Except as otherwise provided herein, Corvas, its
         Affiliates, licensees, or sublicensees, as applicable, shall
         respectively retain all intellectual property rights and title in and
         to any Gene Product(s), Drug Product(s), and inventions relating
         thereto, discovered or developed by or for Corvas, provided, however,
         that with respect to Full Length Clones or Full Length Contigs provided
         to Corvas by Incyte hereunder, Incyte retains the right to file patent
         application(s) with claims directed to composition of matter covering
         such Full Length Clones or Full Length Contigs.

6.3      PATENT PROSECUTION. Except as provided herein, the filing, prosecution,
         maintenance and enforcement of patent(s), copyrights, and other
         proprietary rights regarding the Incyte Technology shall be the
         responsibility of, and at the discretion of Incyte. Both parties shall
         share equally the responsibility and

                                    Page 25
<PAGE>

         expense of filing, prosecuting, maintaining and enforcing any patents,
         copyrights and other proprietary rights created jointly by employees of
         both Parties.

6.4      FREEDOM FROM SUIT: RESEARCH FIELD OF USE. Consistent with the license
         grant of Incyte Patent Rights to Corvas as provided in Section 3.1
         herein, with respect to composition of matter or use claims directed to
         Designated Gene Product(s) owned or controlled by Corvas, its
         Affiliate(s) or sublicensee(s), Corvas (or its Affiliate(s) or
         sublicensee(s) as the case may be) agrees not to sue or bring any
         action in any court or administrative agency or any other government
         authority alleging infringement of said patents as a result of
         activities of Incyte or its affiliates or (sub)licensee(s) in the
         Research Field of Use which would constitute an infringement of said
         patents, and further, Corvas (or its Affiliate(s) or sublicensee(s) as
         the case may be) agrees to extend such freedom from suit or action to
         further (sub)licensee(s) of Incyte, its affiliates, licensees or other
         collaborators of LifeSeq(R) Database Product(s). The foregoing freedom
         from suit provisions shall only apply with respect to such parties
         which have executed an agreement which contains a provision with
         substantially similar rights to Incyte, its affiliates , licensees and
         collaborators with respect to any similar patents rights of said
         affiliate, (sub)licensee or Corvas .

6.5      RESEARCH TOOLS AND DATABASE PRODUCTS OR SERVICES. With respect to
         composition of matter or use claims directed to Designated Gene
         Product(s) owned or controlled by Corvas, its Affiliate(s) or
         sublicensee(s), Corvas (or its Affiliate(s) or sublicensee(s) (other
         than Incyte under Section 6.4 above) as the case may be) agrees not to
         sue or bring any action in any court or administrative agency or any
         other government authority alleging infringement of said patents as a
         result of activities of Incyte or its affiliates or (sub)licensee(s)
         with respect to commercialization of research tools or database
         products or services, including microarray-based research tools or
         database products or services, by Incyte or its affiliates or
         (sub)licensee(s) , which would constitute an infringement of said
         patents, and further, Corvas (or Corvas Affiliate(s) or sublicensee(s)
         as the case may be) agrees to extend such freedom from suit or action
         to further (sub)licensee(s)s of Incyte, its affiliates or licensees
         with respect to commercialization of research tools or database
         products or services.

6.6      CORVAS PATENT INFORMATION. Corvas will provide Incyte with a list of
         the serial numbers of all issued patents or published patent
         applications ("Corvas Patent Information") containing composition of
         matter or use claims directed to Designated Gene Products(s) owned or
         controlled by Corvas, its Affiliate(s) or sublicensee(s), and shall
         update the Corvas Patent Information on a quarterly basis. Incyte will
         make Corvas Patent Information accessible to all licensees and
         collaborators which have executed an agreement which contains a
         provision which grants substantially similar rights to Incyte, its
         Affiliates, licensees and

                                    Page 26
<PAGE>

         collaborators with respect to any similar patents rights of said
         affiliate, (sub)licensee or collaborator.

6.7      INCYTE PATENT INFORMATION. Incyte will provide Corvas with a list of
         the serial numbers of all issued patents ("Incyte Patent Information")
         containing composition of matter or use claims directed to Designated
         Gene Products(s) owned or controlled by Incyte, its Affiliate(s) or
         sublicensee(s), and shall update the Incyte Patent Information on a
         quarterly basis.

6.8      THIRD PARTY PATENTS. Subject to the warranties made hereunder as to
         each Party's knowledge of any third party rights that may be infringed
         by the uses of the Database Information as contemplated herein, the
         Parties acknowledge that, in order to discover, develop, and/or
         commercialize one or more Gene Products, they may require licenses
         under third party patent rights or such other rights,, and it is hereby
         agreed that it shall be each Party's responsibility to satisfy itself
         as to the need for such licenses and, if necessary, to obtain such
         licenses. To the extent that Corvas obtains any such third party
         licenses, it shall have no obligation to grant any sublicense or other
         rights to Incyte or any third party with respect thereto.

7.0 TERM; TERMINATION.
--- -----------------

7.1      TERMINATION AT FULL TERM. This Agreement shall commence as of the
         Effective Date and shall expire on the last day of the Access Term,
         unless terminated earlier as provided under this Section 7.1 or under
         Section 7.3. Corvas shall have the right to terminate the Access Term
         [...***...] after the Effective DaTe, upon thirty (30) days' prior,
         written notice and upon payment to Incyte of a termination fee equal
         [...***...].

7.2      TERM OF LICENSE(S). Upon termination or expiration of the Access Term,
         to retain any license procured under Sections 3.1, Corvas shall, on a
         Designated Gene Product by Designated Gene Product basis, pay to Incyte
         [...***...] or [...***...], until:

              a)    the filing by Corvas of the earlier of an IND (or PMA, 510K,
                    PLA) or equivalent or initiation of Phase I Clinical testing
                    for which a milestone payment as been made pursuant to
                    Article 4.0 in which case such license shall then extend in
                    perpetuity; or

              b)    the license is terminated by Corvas prior to the filing by
                    of an IND (or PMA, 510K, BLA) or equivalent by Corvas, on or
                    before a given anniversary of the Access Term

                                    Page 27    *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

7.3      BREACH. Material failure by either Party to comply with any of its
         obligations under this Agreement shall entitle the other Party to give
         to the Party in default notice specifying the nature of the default and
         requiring it to cure such default. If such default is not cured within
         ninety (90) days after the receipt of such notice, the notifying Party
         shall be entitled, without prejudice to any of its other rights
         conferred on it by this Agreement, in addition to any other remedies
         available to it by law or in equity, immediately to terminate this
         Agreement by giving notice to the other Party. The right of a Party to
         terminate this Agreement, as hereinafter provided, shall not be
         affected in any way by its waiver or failure to take action with
         respect to any previous default.

7.4      ACCRUED RIGHTS SURVIVING OBLIGATIONS. Termination, relinquishment or
         expiration of this Agreement for any reason shall be without prejudice
         to any rights which shall have accrued to the benefit of either Party
         prior to such termination, or expiration. Except as set forth in
         Section 7.3., upon any termination, relinquishment or expiration of
         this Agreement, the following provisions will not terminate, but will
         continue in full force and effect: Articles 2 (database access), 5
         (confidentiality), 6 (intellectual property), 8
         (representations/warranties), 9 (indemnity), and 10 (miscellaneous),
         any licenses or options granted by Incyte or entered into by Corvas,
         and any payment obligations thereunder pursuant to Corvas' rights under
         Articles 3 and 4. In the event the Agreement is terminated by Corvas
         due to a material breach by Incyte, Corvas will maintain a fully
         paid-up, royalty -free, non-exclusive license to develop, use and
         commercialize Designated Gene Products.

8.0 REPRESENTATIONS AND WARRANTIES; COVENANTS.
--- -----------------------------------------

8.1      REPRESENTATIONS AND WARRANTIES. Each Party represents and warrants to
         the other Party that:

                  (a) it is a corporation or entity duly organized and validly
                  existing under the laws of the state or other jurisdiction of
                  incorporation or formation;

                  (b) it has the corporate power and authority and the legal
                  right to enter into this Agreement and to perform its
                  obligations hereunder;

                  (c) the execution and delivery of this Agreement and the
                  performance by such Party of the transactions contemplated
                  hereby have been duly authorized by all necessary corporate
                  action of such Party; and

                  (d) except for the governmental and Regulatory Approvals
                  required to market the Drug Product(s) in the Territory, the
                  execution, delivery and performance of this Agreement by such
                  party does not require the

                                    Page 28
<PAGE>

                  consent, approval or authorization of, or notice, declaration,
                  filing or registration with, any governmental or regulatory
                  authority and the execution, delivery or performance of this
                  Agreement by such party does not violate any law, rule or
                  regulation applicable to such party.

8.2      INCYTE'S REPRESENTATIONS Incyte hereby represents, warrants and
         covenants to Corvas as follows:

                  (a)    to the best of Incyte's knowledge, as of the Effective
                         Date it is the owner, or licensee (with the right to
                         grant sublicenses), of the Incyte Patent Rights and
                         Incyte Know-How, and no other person, corporate or
                         other private entity, or governmental entity or
                         subdivision thereof, has or shall have any claim of an
                         ownership interest with respect to those Incyte Patent
                         Rights and Incyte Know-How owned by Incyte, whatsoever.

         For purposes of this Section 8.2, the term "to the best of Incyte's
         knowledge" shall mean in each case Incyte's best knowledge without
         undertaking any special investigation with respect to such subject
         matter beyond the scope of those diligent investigations normally
         performed by Incyte in the course of its own business operations.

8.3      CORVAS REPRESENTATIONS. Corvas hereby represents, warrants and
         covenants to Incyte that it will comply with its obligation to record
         which Gene Product(s) have been Used by Corvas and to notify Incyte of
         the number of such Gene Product(s) in accordance with the Annual
         Reporting Mechanism.

8.4      NO CONFLICTING AGREEMENTS. Neither Party has in effect and after the
         Effective Date neither Party shall enter into any oral or written
         agreement or arrangement that would conflict with its obligations under
         this Agreement.

8.5      COMPLIANCE WITH LAW. Each Party shall be responsible for compliance
         with all applicable product safety, product testing, product labeling,
         package marking, and product advertising laws and regulations with
         respect to its own activities and Drug Products. Further, Corvas and
         Incyte shall each comply with the regulations of the United States and
         any other relevant nation concerning any use manufacture, export or
         other transfer of technology, services, or products.

8.6      DISCLAIMERS.

         (a) EXCEPT AS EXPLICITLY STATED HEREIN, NOTHING IN THIS AGREEMENT SHALL
         BE CONSTRUED AS A REPRESENTATION MADE OR WARRANTY GIVEN BY INCYTE THAT
         ANY PATENT WILL ISSUE BASED UPON ANY PENDING PATENT APPLICATION WITHIN
         THE INCYTE

                                    Page 29
<PAGE>

         PATENT RIGHTS, THAT ANY PATENT WITHIN THE INCYTE PATENT RIGHTS THAT HAS
         ISSUED OR ISSUES WILL BE VALID, OR THAT THE USE OF ANY LICENSE GRANTED
         HEREUNDER OR THAT THE USE OF ANY INCYTE PATENT RIGHTS WILL NOT INFRINGE
         THE PATENT OR PROPRIETARY RIGHTS OF ANY THIRD PARTY. INCYTE MAKES NO
         REPRESENTATIONS OR WARRANTIES WITH RESPECT TO CORVAS' USE OF THE
         INFORMATION TO BE PROVIDED TO IT HEREUNDER. EXCEPT AS EXPLICITLY STATED
         HEREIN, ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WARRANTIES OF
         MERCHANTABILITY, NOVELTY OR FITNESS OF GENE PRODUCTS OR DATABASE
         INFORMATION FOR ANY PARTICULAR PURPOSE, ARE EXCLUDED. INCYTE MAKES NO
         WARRANTY THAT THE DATABASE INFORMATION DOES NOT CONTAIN ERRORS.

         (b) EXCEPT AS EXPLICITLY STATED HEREIN NEITHER PARTY WILL BE LIABLE FOR
         CONSEQUENTIAL OR INCIDENTAL DAMAGES OF ANY NATURE ARISING FROM SUCH
         PARTY'S ACTIVITIES UNDER THIS AGREEMENT; PROVIDED, HOWEVER, THAT THIS
         LIMITATION SHALL NOT LIMIT THE INDEMNIFICATION OBLIGATION OF INCYTE
         UNDER SECTION 9.2 BELOW FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES
         RECOVERED BY A THIRD PARTY.

9.0 INDEMNITY.
--- ---------

9.1      INDEMNIFICATION BY CORVAS. Corvas shall indemnify, defend and hold
         Incyte, its affiliates and licensees (other than Incyte) harmless from
         and against any and all losses, liabilities, damages and expenses
         (including reasonable attorneys' fees and costs) as the result of
         claims, demands, actions or other proceedings which may be made or
         instituted by any third party against any of them, except to the extent
         such losses, liabilities, damages and expenses (including reasonable
         attorney's fees and costs) resulted from the gross negligence,
         recklessness or intentional misconduct of Incyte, and arising out of
         (i) a material breach of Corvas' representations, warranties or
         covenants under this Agreement, (ii) the development, manufacture,
         possession, distribution, use, testing, sale or other disposition of
         any Drug Product by Corvas, its Affiliates or licensees, (iii) products
         liability arising from the use by any third party of Drug Product(s)
         sold by or on behalf Corvas, its Affiliates or licensees, or (iv) the
         gross negligence, recklessness or intentional misconduct of Corvas or
         its Affiliates in connection with activities to be performed under this
         Agreement.

9.2      INDEMNIFICATION BY INCYTE. Incyte shall indemnify, defend and hold
         Corvas, its Affiliates and licensees harmless from and against any and
         all losses, liabilities, damages and expenses (including reasonable
         attorneys' fees and costs) as the result of claims, demands, actions or
         proceedings which may be made or instituted by any third party against
         any of them arising out of (i) a material

                                    Page 30
<PAGE>

         breach of Incyte's representations, warranties or covenants under this
         Agreement, (ii) the manufacture, possession, distribution, use,
         testing, sale or other disposition of any product by Incyte, its
         affiliates or licensees (other than Corvas, Corvas' Affiliates or
         Corvas' sublicensees), or (iii) the gross negligence, recklessness or
         intentional misconduct of Incyte or its affiliates in connection with
         activities to be performed under this Agreement.

9.3      PROCEDURE. A Party that intends to claim indemnification under this
         Article 9 (the "INDEMNITEE") shall promptly notify the indemnifying
         Party (the "INDEMNITOR") of any loss, liability, damage, expense,
         claim, demand, action or other proceeding in respect of which the
         Indemnitee or any of its affiliates intend to claim such
         indemnification, and the Indemnitor shall have the right to participate
         in, and, to the extent the Indemnitor so desires, jointly with any
         other Indemnitor similarly noticed, to assume the defense thereof with
         counsel selected by the Indemnitor and reasonably satisfactory to the
         Indemnitee; provided, however, that the Indemnitee shall have the right
         to retain its own counsel, with the fees and expenses to be paid by the
         Indemnitee. The indemnity provisions in this Article 9 shall not apply
         to amounts paid in settlement of any loss, liability, damage, expense,
         claim, demand, action or other proceeding if such settlement is
         effected without the consent of the Indemnitor, which consent shall not
         be withheld unreasonably. The failure to deliver notice to the
         Indemnitor within a reasonable time after the commencement of any such
         action, if prejudicial to the Indemnitor's ability to defend such
         action, shall relieve such Indemnitor of any liability to the
         Indemnitee under this Article 9, but the omission so to deliver notice
         to the Indemnitor will not relieve it of any liability that it may have
         to any Indemnitee otherwise than under this Article 9. The Indemnitor
         may not settle the action or otherwise consent to an adverse judgment
         in action or other proceeding that materially diminishes the rights or
         interests of the Indemnitee without the express written consent of the
         Indemnitee. The Indemnitee under this Article 9 and its employees and
         agents, shall cooperate fully with the Indemnitor and its legal
         representatives in the investigation of any action, claim or liability
         covered by this indemnification.

10.0 MISCELLANEOUS PROVISIONS.
---- ------------------------

10.1     NO PARTNERSHIP. Nothing in this Agreement is intended or shall be
         deemed to constitute a partnership, agency, distributorship,
         employer-employee or joint venture relationship between the Parties. No
         Party shall incur any debts or make any commitments for the other,
         except to the extent, if at all, specifically provided herein.

10.2     ASSIGNMENTS. Neither Party shall assign any of its rights or
         obligations hereunder except: (i) as incident to the merger,
         consolidation, reorganization or acquisition of stock or assets or
         similar transaction affecting all or substantially

                                    Page 31
<PAGE>

         all of the assets or voting control of the assigning Party; (ii) in the
         case of Corvas, to any Corvas Affiliate, or, in the case of Incyte, to
         any firm, partnership or legal entity which directly or indirectly
         owns, is owned by or is under common ownership with Incyte, provided
         that the assigning Party remains liable and responsible for such Corvas
         Affiliate's or Incyte subsidiary's performance hereunder, as
         applicable; (iii) with respect to either Party as the assignor, as
         incident to the acquisition or transfer of the assets affecting all or
         substantially all of the assets of the business of the Party relating
         to a given field of use, provided that the acquiring entity or
         transferee continues to fulfill its obligations to the other Party
         hereunder; (iv) with the written consent of the other Party, which
         consent shall not be withheld unreasonably. This Agreement shall be
         binding, upon the successors and permitted assigns of the Parties. Any
         assignment not in accordance with the above shall be void. To the
         extent that any assignment by Corvas hereunder would directly result in
         an increase in any withholding taxes for which Incyte is responsible
         under this Agreement, Corvas shall be responsible for such additional
         taxes.

          [...***...]

         In no event will Corvas' LifeSeq(R) Database Product(s) access rights
         be assignable to a successor or permitted assign if Incyte's
         obligations thereunder would increase materially as a result of the
         assignment (e.g. by having to service additional sites, or where Incyte
         would incur a material increase in expenses and/or services over those
         provided to Corvas hereunder), unless such successor or permitted
         assign provides appropriate pro-rated adjustment of the access fees,
         service charges or Incyte costs incurred, and consistent with access
         fees, service charges or Incyte costs incurred pertaining to comparable
         database services customers.

10.3     NO TRADEMARK RIGHTS. Except as otherwise provided herein, no right,
         express or implied, is granted by this Agreement to use in any manner
         the names "Incyte"

                                    Page 32    *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

         or "Corvas", or any other trade name or trademark of Incyte or Corvas
         or their affiliates in connection with the performance of this
         Agreement.

10.4     PUBLIC ANNOUNCEMENTS. Except as may otherwise be required by law or
         regulation, neither Party shall make any public announcement concerning
         this Agreement or the subject matter hereof without the prior consent
         of the other Party, such consent not to be unreasonably withheld. If
         this Agreement is determined to be material to the business of either
         Party so that its disclosure is required by law or regulation, the
         other Party shall have the right to review and comment on the text of
         the disclosure prior to its release to the public.

10.5     ENTIRE AGREEMENT OF THE PARTIES; AMENDMENTS. This Agreement and the
         other agreements between the Parties of even date herewith constitute
         and contain the entire understanding and agreement of the Parties and
         cancels and supersedes any and all prior negotiations, correspondence,
         representations, understandings and agreements, whether verbal or
         written, between the Parties respecting the subject matter hereof. No
         waiver, modification or amendment of any provision of this Agreement
         shall be valid or effective unless made in writing and signed by a duly
         authorized officer of each of the Parties.

10.6     APPLICABLE LAW. This Agreement shall be governed by and interpreted in
         accordance with the laws of the State of Delaware, without reference to
         the conflicts of law principles thereof. The parties expressly exclude
         application of the United Nations Convention for the International Sale
         of Goods.

10.7     NOTICES AND DELIVERIES. Any notice, requests, delivery, approval or
         consent required or permitted to be given under this Agreement shall be
         in writing and shall be deemed to have been sufficiently given if
         delivered in person, transmitted by commercial overnight courier, or
         transmitted by telex telegram or telecopy (facsimile, with confirmed
         receipt) to the Party to whom it is directed at its address shown below
         or such other address as such Party shall have last given by notice to
         the other Party (referred to herein as "notice"). All notices shall be
         effective upon receipt.

                If to Incyte, addressed to:
                         Incyte Genomics, Inc.
                         3160 Porter Drive
                         Palo Alto, CA 94304
                         Attn:  Roy Whitfield, Chief Executive Officer

                If to Corvas, addressed to:
                         Corvas International, Inc.
                         3030 Science Park Road
                         San Diego, CA 92121
                         Attn: George P. Vlasuk, Ph.D., Chief Scientific Officer

                                     Page 33
<PAGE>

10.8     COUNTERPARTS. This 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.

10.9     FORCE MAJEURE. Force Majeure shall mean an Act of God, flood, fire,
         explosion, earthquake, strike, lockout, casualty or accident, war,
         civil commotion, act of public enemies, blockage or embargo, or any
         injunction, law, order, proclamation, regulation, ordinance, demand or
         requirement of any government or any subdivision, authority
         representative thereof, or the inability to procure or use materials,
         labor, equipment, transportation or energy sufficient to meet
         manufacturing needs without the necessity of allocation, or any other
         cause whatsoever, whether similar or dissimilar to those enumerated
         above, which are beyond the reasonable control of such Party, which the
         Party affected has used its reasonable best efforts to avoid, and which
         prevent, restrict or interfere with the performance by a Party of its
         obligations hereunder. The Party affected by Force Majeure shall give
         notice to the other Party promptly in writing and whereupon shall be
         excused from those obligations hereunder, to the extent of such
         prevention, restriction or interference, provided that the affected
         party shall use its commercially reasonable efforts to overcome, avoid
         or remove such cause(s) of non-performance and shall continue
         performance whenever such cause(s) is removed with all possible speed.
         Nothing herein shall be deemed to require any party to settle on terms
         unsatisfactory to such party with regard to any strike, lock-out or
         other labor difficulty, any investigation or proceeding by any public
         authority or any litigation by any third party.

                                    Page 34
<PAGE>

10.10    AFFILIATE PERFORMANCE. To the extent that any Affiliate of Corvas has
         access to any LifeSeq(R) Database Product(s), has the right to receive
         any other rights or benefits under this Agreement or otherwise is
         obligated to perform any obligations under this Agreement, Corvas shall
         cause such Affiliate to perform in full, when due, all applicable
         obligations under this Agreement to the same extent as if such
         Affiliate were a party to this Agreement; provided, however, that
         nothing in this Section 10.16 shall expand the rights or benefits of
         Corvas or Affiliates of Corvas, or the obligations of Incyte or
         Affiliates of Incyte, beyond those otherwise expressly set forth in
         this Agreement. Corvas shall guaranty timely performance in full by
         such Affiliate of all such obligations. A breach by such Affiliate of
         any such obligation shall constitute a breach by Corvas of this
         Agreement.

IN WITNESS WHEREOF, the Parties have caused this Agreement to be executed by
their respective duly authorized officers as of the Effective Date.

INCYTE GENOMICS, INC.

By:      /s/      Roy A. Whitfeild
   -----------------------------------------

Name:             Roy A. Whitfeild
     ---------------------------------------

Title:            CEO
      --------------------------------------

CORVAS INTERNATIONAL

By:      /s/      George P. Vlasuk
   -----------------------------------------

Name:             George P. Vlasuk, Ph.D.
     ---------------------------------------

Title:            Chief Scientific Officer
      --------------------------------------

                                    Page 35
<PAGE>

EXHIBIT A
---------

LifeSeq Database Product Description as of Effective Date:

o  Over 6.3 million ESTs
o  Over 120,000 human genes; 60,000 of which are Incyte proprietary
o  More than 30,000 5'-complete or full-length gene sequences
o  Highly expressed and "rare" genes
o  Over 1,200 representative tissue sources

LifeSeq(R) Gold online will accelerate scientists' discovery programs and
provide full online access to all of Incyte's public and proprietary data. This
database will also improve scientists' ability to reach their research
milestones and provide regular updates via the Internet without the standard
maintenance and hardware costs.

LifeSeq(R) Gold online is an Incyte-hosted version of the LifeSeq(R) Gold
database. The database contains Incyte proprietary and public gene transcripts
and is updated and assembled with new revisions regularly. Subscribers can
access LifeSeq & Gold online via the Incyte.com web site.

                                    Page 36
<PAGE>

EXHIBIT B
---------

Corvas employees with access to LifeSeq:

[...***...]

                                    Page 37    *CONFIDENTIAL TREATMENT REQUESTED

<PAGE>

EXHIBIT C
---------

Serine Protease Dataset:

[...***...]

                                    Page 38    *CONFIDENTIAL TREATMENT REQUESTED<PAGE>

                                                                   EXHIBIT 10.20

THE ISSUANCE OF THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
1933. THIS NOTE MAY NOT BE SOLD, TRANSFERRED OR ASSIGNED UNLESS SO REGISTERED OR
UNLESS AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT OF 1933 IS
AVAILABLE.

                            INTERACTIVE NETWORK, INC.
                         10% CONVERTIBLE PROMISSORY NOTE

$_______________                                           LOS ALTOS, CALIFORNIA
                                                          ________________, 2001

         Interactive Network, Inc., a California corporation (the "Company"),
for value received, hereby promises to pay to ______________ or its registered
assigns (the "Holder") the principal sum of __________________________ and
___/100 Dollars ($_________) on ___________, 2002. The Company also promises to
pay interest (computed on the basis of a 360-day year) from the date hereof on
the unpaid balance of such principal amount from time to time outstanding at the
rate of ten percent (10%) per annum. Subject to the terms of Section 7, such
interest shall be due and payable on the earlier of the date this Note matures
or upon conversion of this Note, as described below. At the option of the
Company, interest may be paid by the Company either in cash or in newly-issued,
fully paid and non-assessable shares of common stock ("Common Stock") of the
Company, which shares shall have the same value as the dollar amount of interest
due. For this purpose, the value of the shares of Common Stock shall be equal to
the "Market Value" as that term is defined in the "Bridge Warrants" (as the term
"Bridge Warrants" is defined below). The Company shall give to the Holder at
least five (5) business days' notice of its intent to pay the principal amount
of this Note, in whole or in part. This Note is one of a series of promissory
notes issued by the Company in its offering of units beginning in June 2001,
with each unit consisting of a convertible promissory note in the form of this
Note in the original principal amount of $10,000.00 and a warrant (collectively,
the "Bridge Warrants") to purchase 20,000 shares of Common Stock.

1. CONVERSION. The Holder of this Note has the right, at its option, at any time
prior to the payment of the principal amount of this Note, in whole or in part,
to convert all or part of the outstanding principal amount of this Note into
fully-paid and non-assessable shares of common stock of the Company ("Common
Stock") at the rate of one share of Common Stock for $0.50 of outstanding
principal hereof, subject to adjustment as set forth herein (the "Conversion
Price"). In order to exercise this optional conversion privilege, the Holder of
this Note shall surrender this Note to the Company during normal business hours
at the Company's principal executive office, accompanied by written notice in
form satisfactory to the Company that the Holder elects to convert the principal
amount of this Note or a portion hereof specified in such notice. Such notice
shall also state the name of the Holder (with the address) in which the
certificate or certificates for shares of Common Stock issuable on such
conversion shall be issued.

2. SURRENDER OF NOTE AND DELIVERY OF CERTIFICATES. When surrendered for
conversion, this Note shall, unless the shares issuable on conversion are to be
issued in the same name as the name in which this Note is then registered, be
duly endorsed by, or accompanied by instruments of transfer duly executed by,
the Holder or his or its duly authorized attorney. As promptly as practicable
after the surrender of this Note for conversion in accordance with Section 1
above, the Company shall deliver or cause to be delivered at its principal
executive office to the Holder a certificate or certificates for the number of
shares of Common Stock issuable upon the conversion of this Note, or portion
thereof, in accordance with the provisions hereof. Such conversion shall be
deemed to have been made at the time this Note shall have been surrendered for
conversion and the notice specified above shall have been received by the
Company at its principal executive office (the "Conversion Date"), and the
Holder in whose name any certificate or certificates for shares of Common Stock
shall be issuable upon such conversion shall be deemed to have become on the
Conversion Date the holder of record of the shares represented thereby. If less
than the entire outstanding principal amount of this Note is being converted,
the Company shall promptly deliver to the Holder a new Note for the unconverted
principal balance, which Note and shall be of like tenor as to all terms as the
Note surrendered.

                                       14
<PAGE>

3. ADJUSTMENT OF CONVERSION PRICE.

         (a) In case the Company shall:

                  (i) declare a stock dividend on its Common Stock,

                  (ii) subdivide outstanding shares of Common Stock into a large
                  number of shares of Common Stock by reclassification, stock
                  split, or otherwise, or

                  (iii) combine outstanding shares of Common Stock into a
                  smaller number of shares of Common Stock by reclassification
                  or otherwise,

         the number of shares of Common Stock issuable upon conversion of this
         Note immediately prior to any such event shall be adjusted
         proportionately so that thereafter the Holder shall be entitled to
         receive upon conversion of this Note the number of shares of Common
         Stock which such Holder would have owned after the happening of any of
         the events described above had the Note been converted immediately
         prior to the happening of such event, provided that the Conversion
         Price shall in no event be reduced to less than the par value of the
         shares issuable upon conversion. An adjustment made pursuant to this
         Section shall become effective immediately after the record date in the
         case of a dividend and shall become effective immediately after the
         effective date in the case of a subdivision or combination.

         (b) If, prior to maturity of this Note, the Company shall at any time
         consolidate or merge with another corporation or entity (other than a
         merger or consolidation in which the Company is the surviving
         corporation), the Holder will thereafter be entitled to receive, upon
         the conversion hereof, the securities or property to which a holder of
         the number of shares of Common Stock then deliverable upon the
         conversion hereof would have been entitled to receive upon such
         consolidation or merger, and the Company shall take steps in connection
         with such consolidation or merger as may be necessary to ensure that
         the provisions hereof shall thereafter be applicable to any securities
         or property thereafter deliverable upon the conversion of this Note.

4. NOTICE. If the Company proposes to take any action referred to in Section
3(a) or Section 3(b) above, or to effect the liquidation, dissolution, or
winding up of the Company, then the Company shall cause notice thereof to be
mailed to the registered Holder of this Note at least fifteen (15) days prior to
the date on which the transfer books of the Company shall close or a record be
taken for such stock dividend or the date when such reclassification,
liquidation, dissolution or winding up shall be effective, as the case may be.

5. STATEMENT OF ADJUSTMENT. Whenever the Conversion Price shall be adjusted as
provided in Section 3(a) above, the Company shall forthwith file and deliver by
mail, first class, postage prepaid, to the Holder a statement, signed by the
Chairman of the Board, the President, any Vice President, or Secretary of the
Company, showing in reasonable detail and certifying as to the facts requiring
such adjustment and the Conversion Price that will be effective after such
adjustment. Where appropriate, such notice may be given in advance and may be
included as part of a notice required to be mailed under the provision of
Section 4 hereof.

6. FRACTIONAL SHARES. No fractional shares of Common Stock shall be issuable
upon conversion of this Note, but a payment in cash will be made in respect of
any fraction of a share which would otherwise be issuable upon the surrender of
this Note, or portion hereof, for conversion.

7. ACCRUED INTEREST. Upon the payment or conversion of this Note, the Company
shall be required to pay in cash any accrued but unpaid interest on the amount
so converted up to the Conversion Date or date of payment.

8. PREPAYMENT OF PRINCIPAL. The principal indebtedness represented by this Note
may be prepaid in whole or in part without the prior written consent of the
Holder of this Note.

                                       15
<PAGE>

9. DEFAULT. The entire unpaid principal of this Note and the interest then
accrued on this Note shall become and be immediately due and payable upon
written demand of the Company by the Holder of this Note, without any other
notice or demand of any kind or any presentment or protest, if any one of the
following events shall occur and be continuing at the time of such demand,
whether voluntarily or involuntarily, or, without limitation, occurring or
brought about by operation of law or pursuant to or in compliance with any
judgment, decree or order of any court or any order, rule or regulation of any
governmental body:

         (a) If the Company (i) makes a composition or an assignment for the
         benefit of creditors, (ii) applies for, consents to, or acquiesces in,
         a petition seeking the appointment of a trustee, receiver or
         liquidator, in bankruptcy or otherwise, of itself or of all or a
         substantial portion of its assets, or (iii) admits in writing its
         inability to pay its debts generally as they become due; or

         (b) If an order for relief shall have been entered by a bankruptcy
         court or if a decree, order or judgment shall have been entered
         adjudging the Company insolvent, or appointing a receiver, liquidator,
         custodian or trustee; or

         (c) If the Company fails to pay principal and interest under this Note
         when due, or otherwise breaches any of its obligations or
         representations in any material respect under this Note.

10. SENIORITY. In the event of any distribution of the assets of the Company
upon dissolution, liquidation or reorganization, the Holder of this Note will be
entitled to receive payment in full of the indebtedness evidenced by this Note
prior to the payment by the Company of any other indebtedness of the Company.

11. WAIVERS. The Company waives presentment, demand, protest, notice of protest,
notice of presentment and all other notices and demands in connection with the
enforcement of the rights of the Holder of this Note. Any failure of the Holder
to exercise any right available hereunder or otherwise shall not be construed as
a waiver of the right to exercise the same right or any other right.

12. TRANSFER OR EXCHANGE. Whenever this Note shall be surrendered at the
principal executive office of the Company for transfer or exchange, accompanied
by a written instrument of transfer duly executed by the Holder hereof (or its
duly authorized attorney in writing), the Company shall execute and deliver in
exchange for this Note a new Note or Notes, as may be requested by such Holder,
in the same aggregate unpaid principal amount and payable on the same date as
the principal amount of the Note or Notes so surrendered; and each such new Note
shall be in such principal amount and registered in such name or names as such
Holder may designate in writing.

13. LOSS OR DESTRUCTION OF NOTE. Upon receipt by the Company of evidence
reasonably satisfactory to it of the loss, theft, destruction or mutilation of
this Note and of indemnity reasonably satisfactory to it, and upon reimbursement
to the Company of all reasonable expenses incidental thereto, and upon surrender
and cancellation of this Note (in case of mutilation), the Company will make and
deliver in lieu of this Note a new Note of like tenor and unpaid principal
amount.

14. SUCCESSORS AND ASSIGNS. This Note, and the obligations and rights of the
Company hereunder, shall be binding upon and inure to the benefit of the
Company, the Holder of this Note, and their respective successors and assigns.

15. ENFORCEABILITY. The Company represents that this Note is enforceable against
the Company in accordance with its terms.

16. CURRENCY. All payments shall be made in the currency of the United States of
America as at the time of payment shall be legal tender therein for the payment
of public and private debts.

                                       16
<PAGE>

17. NOTICES. All notices, requests, consents and demands shall be made in
writing and shall be mailed postage prepaid, or delivered by hand, to the
Company or to the Holder at their respective addresses set forth below or to
such other address as may be furnished in writing to the other party hereto:

         If to the Holder:   _____________________________
                             _____________________________
                             _____________________________
                             Attention: __________________

         If to the Company:  Interactive Network, Inc.
                             180 Second Street, Suite B
                             Los Altos, California  94022
                             Attention:  Mr. Bruce W. Bauer
                             (650) 947-3345 telephone
                             (650) 917-1615 facsimile

18. GOVERNING LAW. This Note shall be construed and enforced in accordance with,
and the rights of the parties shall be governed by, the laws of the State of
Delaware, without reference to Delaware's choice of law provisions.

19. REGISTRATION. The Company will register the resale of the shares of the
Company's common stock into which this Note may be converted under the
Registration Statement on Form S-4 to be filed by the Company in connection with
its proposed merger with TWIN Entertainment, Inc.

         IN WITNESS WHEREOF, this Note has been executed and delivered on the
date first above written by the duly authorized representative of the Company.

                                             Interactive Network, Inc.

                                             ___________________________________
                                             (Name)
                                             (Title)

ATTEST: ___________________________________
        Secretary

                                       17

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