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                                                                   EXHIBIT 10.28

                         INTERCOMPANY SERVICES AGREEMENT

        THIS INTERCOMPANY SERVICES AGREEMENT ("Agreement"), is entered into on
September 2, 1997, to be effective as of the Effective Date (as defined herein),
by and among INCYTE PHARMACEUTICALS, INC., a Delaware corporation ("Incyte"),
SMITHKLINE BEECHAM CORPORATION, a Pennsylvania corporation ("SB") and DIADEXUS,
LLC, a Delaware limited liability company (the "LLC").

                                   RECITALS:

        A. Incyte and SB each own beneficially a substantial portion of the
membership interests in the LLC.

        B. The LLC is a development stage biotechnology company that will be
engaged in the business of discovering, developing, manufacturing and marketing
molecular diagnostic Tests (as defined in that certain Collaboration and License
Agreement by and among Incyte, SB and the LLC of even date herewith), and doing
all things necessary or related to these purposes as may be determined from time
to time by the LLC in accordance with the Operating Agreement governing the LLC.

        C. In connection with the LLC's formation, the parties desire (i) to set
forth the terms and conditions under which the LLC may retain Incyte and/or SB
to perform certain services (the "Services"), and (ii) to establish and maintain
certain other policies and procedures in connection with the LLC.

        NOW, THEREFORE, in consideration of the foregoing and the mutual
agreements, provisions and covenants contained in this Agreement, the parties
hereby agree as follows:

                                   ARTICLE I.

                              PROVISION OF SERVICES

SECTION 1.1. TYPES OF SERVICES

        The LLC hereby engages and retains Incyte and SB to provide any of the
Services set forth below, subject to Section 1.2(b), from time to time as and to
the extent reasonably requested by the LLC and agreed to by the Service Provider
(as defined below) from time to time, upon the terms and conditions hereinafter
set forth:

                (i) executive and administrative;

                (ii) regulatory, including such Services as are necessary or
        useful to assist the LLC in meeting reporting requirements of regulatory
        agencies;


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                (iii) tax advice and services, including, without limitation,
        assistance in the preparation of federal, state, local and foreign tax
        returns;

                (iv) auditing, accounting, payroll and bookkeeping advice and
        services, including services related to financial reporting and
        assistance in the preparation of financial statements whether or not
        related to the reporting requirements under the federal securities laws;

                (v) financial advice and services, including, without
        limitation, assistance with respect to cash management, treasury and
        risk management;

                (vi) human resources and personnel policies, including, without
        limitation, wage and salary, administrative, employee relations and
        administration of employee insurance plans and other employee benefits
        plans;

                (vii) assistance with marketing projects, consumer studies and
        other information gathering or promotional activities;

                (viii) purchasing services, and assistance in the purchase or
        leasing of equipment and supplies, including where possible and
        acceptable to Incyte and SB making available to the LLC volume purchase
        discount arrangements and group rates for purchasing insurance,
        equipment and other supplies and services;

                (ix) facilities services, including mail, telephone, supply,
        food service and employee services;

                (x) management information, supplemental data processing,
        telecommunications, computer programming and other computer systems
        services; and

                (xi) such other services, advice and assistance as may be
        reasonably requested by the LLC and agreed to by a Service Provider
        from time to time.

SECTION 1.2. PERFORMANCE

        (a) All Services provided by Incyte or SB hereunder shall be performed
only at the request and under the general direction of the LLC and neither
Incyte nor SB shall have any power to act independently on behalf of the LLC in
performing Services hereunder other than as specifically authorized hereunder or
as requested from time to time by the LLC. Neither Incyte, SB, nor the
employees, vendors, agents, affiliates or suppliers of either of them, shall be
deemed to be agents, representatives, employees or servants of the LLC, except
to the extent expressly provided pursuant to the authority granted under this
Agreement.

        (b) Each of Incyte and SB shall have sole discretion as to whether
Incyte or SB, respectively, shall provide any Service requested by the LLC. The
specified Services provided to the LLC at any time by either Incyte or SB and
the specified terms and conditions under which they shall be provided shall be
set forth in a separate schedule to this Agreement, which shall


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become effective only upon its execution by Incyte or SB (or such other person
or entity designated as a Service Provider pursuant to section 1.2(c)), as the
case may be, and the LLC, or, to the extent agreed by the Service Provider and
the LLC, in a separate agreement, in each case subject to any approval as is
necessary under that certain LLC Operating Agreement by and between SB and
Incyte of even date herewith.

        (c) Any Services provided to the LLC by Incyte or SB, as the case may
be, may be performed by such entity or by such affiliates or agents thereof as
such entity may reasonably determine so long as such entity providing the
Service is obligated to the LLC hereunder (or, if such entity and the LLC so
agree, is obligated to the LLC under a separate agreement). Any entity
performing services for the LLC under this Agreement on behalf of either Incyte
or SB, as the case may be, shall be included in the definition of "Service
Provider," but all such references to Service Provider shall in any event refer
to whichever of Incyte or SB, as the case may be, is obligated to perform such
Services for the LLC.

        (d) A Service Provider shall, in its sole discretion, determine which of
its corporate facilities to be used in rendering a Service and the individuals
who will render such Service.

        (e) Services provided to the LLC hereunder shall be performed by those
employees of the Service Provider who perform comparable services for the
Service Provider in the normal course of their employment. A Service Provider
shall not be obligated to make available any Services to the LLC that the
Service Provider does not perform with respect to its own operations, or if
providing such Service would unreasonably interfere with the performance by any
employee of Services for the Service Provider, or otherwise cause an
unreasonable burden to the Service Provider.

        (f) Nothing herein shall be deemed to restrict the Service Provider or
its directors, officers or employees from engaging in any business other than
that contemplated herein, or from contracting with other parties, including, its
subsidiaries or affiliates, for similar or different services.

SECTION 1.3. COMPENSATION; REIMBURSEMENTS

        The LLC shall pay to the Service Provider, with respect to the Services
performed by the Service Provider hereunder, reasonable compensation to
reimburse it for the costs incurred by the Service Provider in providing
Services to the LLC; the exact amount of such compensation shall be agreed to by
the LLC and the respective Service Provider and set forth in the applicable
schedule hereto (or separate agreement) from time to time. In addition to the
costs of providing the Services, the Service Provider shall be entitled to
reimbursement of the costs of goods or materials purchased on behalf of the LLC
and paid for by the Service Provider. It is not the intention of the parties
that the Service Provider should obtain profit from providing Services to the
LLC under this Agreement.


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SECTION 1.4. BOOKS AND RECORDS

        The Service Provider shall keep accurate books and records with respect
to the costs and expenses incurred in connection with the Services, and the LLC
and its auditors shall be permitted from time to time upon reasonable notice to
inspect the books and records with respect to such costs and expenses.

                                   ARTICLE II.

                               OTHER COORDINATION

        (a) Incyte and SB, in the sole discretion of Incyte and SB, as the case
may be, may use reasonable efforts to assist the LLC in obtaining the benefits
of any available group pricing or group discounts for the purchase of equipment,
supplies or services (including without limitation insurance) available to
Incyte and SB, as the case may be.

        (b) If a Service Provider provides the LLC with human resources
Services, such Service Provider, if it so elects, may provide the following
health and welfare benefits coverage to the LLC employees on the same terms and
conditions as provided to employees of the Service Provider, but in no event at
a cost to such employees greater than the cost to the Service Provider (except
to the extent of state, regulatory or other factors which cause variance in
premium costs):

                (i) comprehensive health insurance, including medical and dental
        insurance, and covering active and retired employees;

                (ii) life insurance;

                (iii) accidental death or dismemberment;

                (iv) long-term disability insurance; and

                (v) travel accident insurance.

        (c) The LLC shall pay or reimburse the Service Provider for the costs of
any such insurance and health and welfare benefits coverage in accordance with
Section 1.3, provided that such costs shall be no greater than as charged to,
and on substantially the same terms as made available to, internal units of the
Service Provider.


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                                  ARTICLE III.

                        STANDARD OF CARE; INDEMNIFICATION

SECTION 3.1. STANDARD OF CARE

        (a) Each of Incyte and SB makes no express or implied representations,
warranties, or guarantees relating to the Services or the quality or results of
Services to be performed under this Agreement. For purposes of this Article III,
"Incyte" and "SB" shall be deemed to include any of their respective affiliates
that are Service Providers pursuant to this Agreement.

        (b) Nothing in this Agreement shall require Incyte or SB to provide or
develop additional support or to render any Service which it does not
specifically agree to provide pursuant to the terms hereof, or in a manner or
pursuant to methods different from that provided herein, in a schedule hereto or
a separate agreement contemplated hereby, or, in performing Services hereunder,
to make any change or addition which will require capital expenditures.

        (c) The duties of each of Incyte and SB under this Agreement are subject
to interruption or discontinuance by the Service Provider or the LLC at any time
and from time to time, for force majeure or other causes beyond Incyte's, SB's
or the LLC's control, without incurring liability to any party or any other
person for any loss, damage or expense which may result therefrom.

        (d) Either Incyte or SB, as applicable, will use reasonable efforts to
provide any Services with substantially the same degree of care as it provides
the same Services to its own operations. Neither Incyte nor SB shall be liable
to the LLC or any other person for any loss, damage or expense which may result
therefrom or from Incyte or SB's changing its manner of rendering the Services
if Incyte or SB, as applicable, deems that such change is necessary to
desirable in the conduct of its own operations.

        (e) Neither Incyte, SB, their respective officers and employees, nor any
Service Provider shall be liable to the LLC or any third party, including
governmental agencies, for any claims, damages or expenses relating to the
Services provided pursuant to this Agreement except for willful misconduct, bad
faith or gross negligence in their respective performance of Services hereunder
and the LLC shall have the ultimate responsibility for all Services provided
herein.

        (f) Neither Incyte, SB nor any Service Provider shall be liable to the
LLC for the consequences of any failure or delay to perform any of its
respective obligations under this Agreement other than for damages arising from
either of Incyte or SB's willful misconduct, bad faith or gross negligence;
provided that Incyte, SB or a Service Provider, as the case may be, shall
provide reasonably prompt notice to the LLC of such liability and the reasons
therefor.

SECTION 3.2. INDEMNIFICATION FOR SERVICES

        (a) Each of Incyte and SB will indemnify, defend and hold harmless the
LLC and its directors, officers, employees and agents from and against any and
all claims, actions,


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proceedings, judgments, expenses, damages and liabilities, including court costs
and reasonable attorneys fees (collectively, "Claims"), arising out of the
indemnifying party's performance, as applicable, of the Services provided by
such party hereunder (including Services provided by other Service Providers
designated by the indemnifying party, as applicable) due to the indemnifying
party's willful misconduct, bad faith or gross negligence.

        (b) The LLC will indemnify, defend and hold harmless each of Incyte and
SB and other Service Providers designated by either of them and their respective
directors, officers, employees and agents from and against any and all Claims
arising out of the indemnified party's performance, as applicable, of the
Services provided by such party hereunder (including Services provided by other
Service Providers designated by the indemnified party, as applicable), other
than Claims due to the indemnified party's willful misconduct, bad faith or
gross negligence.

                                  ARTICLE IV.

                                  MISCELLANEOUS

SECTION 4.1. ASSIGNMENTS.

        This Agreement shall be binding upon and inure to the benefit of the
successors in interest of the respective parties. Neither this Agreement nor any
interest hereunder shall be assignable by any party without the written consent
of the other; provided, however, that either party may assign this Agreement or
any of its rights or obligations hereunder to any affiliate or to any third
party with which it may merge or consolidate, or to which it may transfer all or
substantially all of its assets to which this Agreement relates, without
obtaining the consent of the other party, provided the assigning party remains
liable under this Agreement and that the, third party assignee or surviving
entity assumes in writing all of the assigning party's obligations under this
Agreement.

SECTION 4.2. FURTHER ACTIONS.

        Each party agrees to execute, acknowledge and deliver such further
instruments, and to do all such other acts, as may be necessary or appropriate
in order to carry out the purposes and intent of this Agreement.

SECTION 4.3. SEVERABILITY.

        In the event any one or more of the provisions of this Agreement should
for any reason be held by any court or authority having jurisdiction over this
Agreement (including arbitrators) or any of the parties to be invalid, illegal
or unenforceable, such provision or provisions shall be validly reformed to as
nearly as possible approximate the intent of the parties and, if unreformable,
shall be divisible and deleted in such jurisdiction; elsewhere, this Agreement
shall not be affected so long as the parties are still able to realize the
principal benefits bargained for in this Agreement.


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SECTION 4.4. CAPTIONS.

        The captions to this Agreement are for convenience only, and are to be
of no force or effect in construing or interpreting any of the provisions of
this Agreement.

SECTION 4.5. APPLICABLE LAW.

        This Agreement shall be governed by and interpreted in accordance with
the laws of the State of California, without reference to the conflicts of law
principles thereof.

SECTION 4.6. NOTICES AND DELIVERIES.

        All notices, requests, demands, consents and other communications given
or required to be given under this Agreement and under the related documents
shall be in writing and delivered to the applicable party at the address
indicated below:

        If to Incyte:   Incyte Pharmaceuticals, Inc.
                        3174 Porter Drive
                        Palo Alto, CA 94304
                        Attention: Chief Executive Officer
                        Tel: (650) 855-0555
                        Fax: (650) 845-4500

        If to SB:       SmithKline Beecham Corporation
                        709 Swedeland Road
                        P.O. Box 1539
                        King of Prussia, PA 19406
                        Attention: John Keller
                        Tel: (610) 270-5973
                        Fax: (610) 270-5964

        With a copy to: SmithKline Beecham Corporation
                        One Franklin Plaza
                        Philadelphia, PA 19406
                        Attention: Don Parman
                        Tel: (215) 751-4000
                        Fax: (215) 751-5349

       If to the LLC:   To be provided by notice to Incyte and SB.

        With a copy to: each of Incyte and SB.

or, as to each party at such other address as shall be designated by such party
in a written notice to the other party complying as to delivery with the terms
of this Section. Any notices shall be in writing, including telegraphic or
facsimile communication, and may be sent by registered or


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certified mail, return receipt requested, postage prepaid, by fax or by
overnight delivery service. Notice shall be effective upon actual receipt
thereof.

SECTION 4.7. 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.

        IN WITNESS WHEREOF, the parties have caused this Agreement to be duly
executed as of the date first above written.

                                   INCYTE PHARMACEUTICALS, INC.

                                   By: /s/ RANDAL SCOTT
                                      -------------------------------

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

                                   Title:

                                   SMITHKLINE BEECHAM CORPORATION

                                   By: /s/ GEORGE POSTE
                                      -------------------------------

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

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

                                   DIADEXUS, LLC

                                   By: /s/ PATRICK PLEWMAN
                                      -------------------------------

                                   Name: Patrick Plewman
                                        -----------------------------

                                   Title: VP, Corporate Development
                                         ----------------------------


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