<PAGE>
                                                                Exhibit 10.16



                              AMENDED AND RESTATED
                        GLOBAL CLINICAL TRIALS AGREEMENT



                                     BETWEEN



                             SMITHKLINE BEECHAM PLC
                              D/B/A GLAXOSMITHKLINE



                                       AND



                         QUEST DIAGNOSTICS INCORPORATED





                          DATED AS OF DECEMBER 19, 2002



<PAGE>

                                TABLE OF CONTENTS

                                                                            PAGE
                                                                            ----
SECTION I.        DEFINITIONS..................................................1

SECTION II.       STATEMENT OF WORK............................................7

SECTION III.      EXCLUSIVITY..................................................9

SECTION IV.       RELATIONSHIP MANAGEMENT.....................................13

SECTION V.        REVIEW AND IMPROVEMENT OF SERVICES..........................15

SECTION VI.       CERTAIN PERFORMANCE METRICS AND MEASURES....................15

SECTION VII.      STUDY PREPARATION PHASE.....................................16

SECTION VIII.     STUDY MANAGEMENT............................................21

SECTION IX.       SPECIMEN TRANSPORT..........................................22

SECTION X.        RESULT REPORTS..............................................24

SECTION XI.       DATA MANAGEMENT REQUIREMENTS................................25

SECTION XII.      MANAGEMENT REPORTING........................................26

SECTION XIII.     LABORATORY METHODOLOGY......................................26

SECTION XIV.      LABORATORY EQUIPMENT........................................27

SECTION XV.       COMPENSATION................................................28

SECTION XVI.      AUDITS, INSURANCE AND PERSONNEL CHANGES.....................32

SECTION XVII.     SERVICE MINIMUMS AND INCENTIVES.............................34

SECTION XVIII.    CONFIDENTIALITY/OWNERSHIP OF SPECIMENS/DATA.................37

SECTION XIX.      CANCELLATION................................................39

SECTION XX.       TERM AND OBLIGATIONS SURVIVING TERMINATION..................39

SECTION XXI.      BREACH......................................................39

SECTION XXII.     INDEMNIFICATION.............................................42

SECTION XXIII.    ASSIGNABILITY AND AMENDMENTS................................46

<PAGE>


SECTION XXIV.     CHANGE IN CONTROL OF GSK....................................47

SECTION XXV.      GOVERNING LAW...............................................47

SECTION XXVI.     INTERPRETATION..............................................47

SECTION XXVII.    NOTICES.....................................................48

SECTION XXVIII.   ENFORCEMENT.................................................49

SECTION XXIX.     INTEGRATION.................................................50

                  xxxx

EXHIBITS
--------
A:       FORM OF TASK DESCRIPTION
B-1:     NORTH AMERICAN TERRITORY CENTRAL LAB WORKSHEET
B-2:     EUROPE CENTRAL LAB WORKSHEET
C-1:     FEE SCHEDULE-NORTH AMERICAN TERRITORY
C-2:     FEE SCHEDULE-EUROPEAN TERRITORY
D:       PERFORMANCE METRICS AND MEASUREMENTS
E:       RESULT\VIEW(TM) ADDITIONAL SERVICE SCHEDULE
F:       MINIMUM CHARGES
G:       CHANGE IN SCOPE FORM
H:       CHARGES FOR HARD COPY LAB REPORTING

<PAGE>


         THIS AMENDED AND RESTATED GLOBAL CLINICAL TRIALS AGREEMENT, dated as of
December 19, 2002 (this "Agreement"), is between SMITHKLINE BEECHAM plc, D/B/A
GLAXOSMITHKLINE, a public limited company organized under the laws of England
("GSK"), and QUEST DIAGNOSTICS INCORPORATED, a Delaware corporation ("Quest") .

         WHEREAS, SmithKline Beecham plc and Quest entered into a Global
Clinical Trials Agreement dated as of August 16, 1999 (the "Original
Agreement"), whereby SmithKline Beecham plc agreed to contract with Quest to
provide, on an exclusive basis, all of SmithKline Beecham plc's clinical trials
testing requirements for a period of 10 years, subject to certain exceptions set
forth in the Original Agreement;

         WHEREAS, after execution of the Original Agreement, SmithKline Beecham
plc became a subsidiary of GlaxoSmithKline plc, resulting in the imposition of
certain annual minimum payment requirements on GSK under the Original Agreement;
and

         WHEREAS, GSK and Quest desire to amend and restate the Original
Agreement to change the minimum payment requirements and make certain other
revisions to the Original Agreement.

         NOW, THEREFORE, in consideration of the mutual covenants and
undertakings contained herein, and subject to and on the terms and conditions
herein set forth, the parties hereto agree as follows:

SECTION I. DEFINITIONS

1.       For purposes of this Agreement:

         "AMS TARGET" means for any year the target for GSK's annual minimum
         spend for Services rendered by Quest set forth in Section XVII(1).

         "AFFILIATE" means, with respect to any Person, any Person which,
         directly or indirectly, Controls, is controlled by, or is under common
         Control with, the specified Person. An Affiliate, with respect to GSK,
         shall include the GSK Subsidiaries.

         "ARCHIVAL SPECIMEN" means a type of specimen which is placed in
         long-term storage by Quest, at GSK's request, either for a particular
         use or for undefined future use.

         "BDS" means the Biomedical Data Sciences department of GSK and any
         successor department.

         "CHANGE IN CONTROL" means any event where:

<PAGE>

         (a)      any "person" or "group" (as such terms are used in Section
                  13(d) and 14(d) of the of the Securities Exchange Act of 1934,
                  as amended (the "Exchange Act")) is or becomes the "beneficial
                  owner" (as defined in Rules 13d-3 and 13d-5 under the Exchange
                  Act) of shares representing more than 50% of the combined
                  voting power of the then outstanding securities entitled to
                  vote generally in elections of directors of GSK Parent (the
                  "Voting Stock"); or

         (b)      GSK consolidates with or merges into any other corporation, or
                  conveys, transfers or leases all or substantially all of its
                  assets (other than to a wholly-owned subsidiary of GSK Parent)
                  or any other corporation merges into GSK Parent, and, in the
                  case of any such transaction, the outstanding common stock of
                  GSK Parent is reclassified into or exchanged for any other
                  property or security, unless the shareholders of the GSK
                  Parent immediately before such transaction own, directly or
                  indirectly, immediately following such transaction, at least a
                  majority of the combined voting power of such outstanding
                  power of the outstanding voting securities of the corporation
                  resulting from, or to which its assets were conveyed,
                  transferred or leased in connection with, such transaction in
                  substantially the same proportion as their ownership of the
                  Voting Stock immediately before such transaction;

         "CLW" means a clinical laboratory worksheet, a document substantially
         in the form of Exhibit B-1 in the case of any Study in the North
         American Territory, and in the form of Exhibit B-2 in the case of any
         Study in the European Territory, or in such other form as may be
         mutually agreed by GSK and Quest. Such document shall be completed by
         representatives of both GSK and Quest with respect to any Study. The
         CLW for any Study is hereby deemed a part of the Task Description for
         such Study and all references herein to any Task Description include
         the CLW, as amended, executed in connection therewith.

         "CONTROL" means, as applied to any Person, the possession, directly or
         indirectly, of the power to direct or cause the direction of the
         management of that Person, whether through ownership of voting
         securities or otherwise.

         "DMPK" means distribution, metabolism and pharmokinetics of a
         pharmaceutical compound (measurement of the pharmaceutical compound or
         its metabolites in body fluid).

         "EUROPEAN TERRITORY" means the countries of Austria, Belgium, the Czech
         Republic, Denmark, Finland, France, Germany, Holland, Hungary, Iceland,
         Ireland, Italy, Lithuania, Luxembourg, Norway, Poland, Portugal,
         Slovakia, Sweden, Spain, Switzerland and the United Kingdom.


                                       2

<PAGE>

         "GSK BIOLOGICALS" means GlaxoSmithKline Biologicals S.A., GSK
         Biologicals Manufacturing, S.A., GSK Biologicals Services, S.A. and GSK
         Biotech, S.A., each a company organized under the laws of Belgium.

         "GSK CLINICAL STUDY LEADER" means with respect to any Study, the GSK
         contact identified in the Task Description for such Study as the lead
         contact at GSK for such Study.

         "GSK PARENT" means GlaxoSmithKline plc and, following a Change in
         Control, any person or group that becomes the beneficial owner of more
         than 50% of the combined voting power of the then outstanding
         securities entitled to vote generally in the election of directors of
         GSK or the party into which the then GSK Parent merges or to which it
         conveys, transfers or leases all or substantially all of its assets
         (other than to a wholly-owned subsidiary of GSK Parent).

         "GSK SUBSIDIARY" means (i) any direct or indirect Subsidiary of GSK
         Parent existing as of the date hereof or formed or acquired by GSK
         Parent during the Term of this Agreement; provided, however, that the
         term "GSK Subsidiary" shall not include GSK Biologicals unless, and
         only to the extent, GSK elects to have GSK Biologicals conduct any
         Studies under this Agreement, and (ii) any Affiliate of GSK Parent
         which GSK elects to have Studies conducted under this Agreement, but
         only to the extent of such election, in the case of each clauses (i)
         and (ii), for so long as such Subsidiary or Affiliate remains a
         Subsidiary or Affiliate of GSK Parent.

         "INADVERTENT OR DE MINIMIS BREACH" means any breach or series of
         breaches which are unintentional, are not reckless or done in bad
         faith, and in the aggregate for a given year do not affect Services in
         excess of $500,000.

         "INVESTIGATOR" means a physician or other clinician who oversees the
         conduct of a Study.

         "INVESTIGATOR MANUAL" means a document used by the Investigators and
         their staffs which provides precise instructions concerning specimen
         collection, transport and reporting and includes laboratory
         certifications.

         "INVESTIGATOR (LAB REQUIREMENT) SUMMARY" means a condensed version of
         the Investigator Manual.

         "NORTH AMERICAN TERRITORY" means the United States of America,
         including Alaska, Hawaii and Puerto Rico, and Canada and Mexico.

         "OTHER STUDY" means clinical research or clinical investigations which
         are not for a specific drug (including but not limited to research into
         disease states and genetics).

         "PERSON" means any individual, firm, corporation, partnership, limited
         liability company, trust, joint venture, governmental entity or other
         entity.


                                       3

<PAGE>

         "QUEST DIAGNOSTICS CLINICAL TRIALS" means the wholly-owned division of
         Quest through which Quest engages, on a global basis, in its clinical
         trials central laboratory business in support of clinical trials of
         pharmaceutical and bio-technology clients.

         "QUEST PROJECT LEADER" means, with respect to any Study, the Person
         appointed by Quest to manage the protocol for such Study. The Quest
         Project Leader will interact on a regular basis with a designated GSK
         contact. Both the Quest Project Leader and the GSK contact for any
         Study shall be identified in each Task Description.

         "REFERRAL SPECIMEN" means a type of specimen which is sent by Quest to
         another laboratory for analysis, with the consent of GSK or a GSK
         Subsidiary.

         "RESULT/VIEW(TM)" means the Quest software product for providing near
         real-time access to clinical trial laboratory data of laboratory tests
         performed by Quest.

         "SERVICES" means laboratory testing, extraction of DNA, specimen
         storage for both analyzed and nonanalyzed specimens, specimen
         transportation, other distribution of materials or supplies, study
         preparation and management, data management (including access to
         Result/View(TM) as provided in Section VII(10), management reporting,
         technical support, reporting of test results, maintenance of good
         laboratory practices and documentation of quality assurance and control
         and all other customary services performed, in each case, in connection
         with a Study.

         "STUDY" means clinical trials or clinical investigations on humans for
         a drug (whether or not the drug is owned by GSK and including but not
         limited to a pharmaceutical compound, biological product or vaccine)
         and, unless otherwise noted, Other Studies.

         "STUDY BLIND" means, with respect to any Study, the confidential
         assignment of participants to a treatment group in order to minimize
         patient, Investigator and Study sponsor bias.

         "SUBSIDIARY" of any Person means another Person, an amount of the
         voting securities, other voting ownership or voting partnership
         interests of which is sufficient to elect at least 50% or more of its
         Board of Directors or other governing body (or, if there are no such
         voting interests, 50% or more of the equity interests of which) is
         owned by such first Person or by another Subsidiary of such Person.

         "3.I SHEETS" means a request form sent to all International
         Investigators requesting certain site information, including the
         location of the Investigator and Co- Investigators, the primary contact
         person and his or her telephone and facsimile numbers, the location for
         specimen collection and the location to which patient reports should be
         sent.


                                       4

<PAGE>

         "TERM" means the period of time defined in Section XX(1).














                                       5

<PAGE>
2.       The following terms have the meanings set forth in the Sections set
         forth below:

<TABLE>
<CAPTION>
Term                                                         Section
--------------------------------                             -----------
<S>                                                          <C>
Acquired Business                                            III(1)(iii)
Agreement                                                    Preamble
Alerts                                                       XI(2)
Alternative Laboratory Agreement                             II(3)
Change in Control Date                                       XXIV
CRO                                                          III(1)(ii)
Credit                                                       XVII(5)
Custom Tests                                                 XV(2)(iii)
DMPK Specimens                                               IX(8)
Existing GSK Compounds                                       XXIV
GSK                                                          Preamble
GSK Discount                                                 XV(1)(ii)
GSK Group                                                    XV(1)
Indemnified party                                            XXII(5)
JOC                                                          IV(2)
Lab Test List                                                XIII(2)
Losses                                                       XXII(1)
Material Breach                                              XXI
MFN Period                                                   XV(2)(ii)
Most Favored Nations Pricing                                 XV(1)(i)
New Capability                                               III(2)(iv)
Other Client                                                 XV(2)(iii)
Original Agreement                                           Preamble
Pivotal                                                      IV(3)(i)
QDCT Referrals                                               II(2)(iii)
QDCT Referral Laboratory                                     II(2)(iii)
Quest                                                        Preamble
Repeated and Continuous Failure                              XXI(5)
Six Year Period Revenue                                      XVII(2)
Spend Targets                                                III(1)(iii)
Successor Company                                            XXIV
Task Description                                             II(2)
TCV                                                          XVII(2)
Third Party Claim                                            XXII(5)
2002 Revenues                                                XVII(1)(i)
2003 Revenues                                                XVII(1)(ii)
Voting Stock                                                 I(1)
</TABLE>

                                       6

<PAGE>

SECTION II. STATEMENT OF WORK

1.       For the avoidance of doubt in interpreting this Agreement, the parties
         intend that Quest perform, on an exclusive basis, all of the laboratory
         testing and other Services needed by GSK in connection with Studies
         (subject to the further provisions of this Section II and the
         exceptions to exclusivity in Section III). It is also the intention of
         the parties that GSK may utilize Quest for additional testing and
         service needs in connection with its research and development efforts.
         Finally, the parties intend to establish a process for evaluating
         opportunities for Quest to perform testing and other services beyond
         those customarily performed for GSK within Quest Diagnostics Clinical
         Trials.

2.       Whenever a member of the GSK Group is required under this Agreement or
         otherwise desires to obtain Services from Quest under this Agreement,
         GSK shall provide Quest Diagnostics Clinical Trials with all relevant
         and necessary information required for Quest to evaluate the request in
         accordance with the applicable provisions of this Agreement. The Quest
         Supplier Relationship Manager at GSK, or his or her successor or
         designees, shall provide such information to the Quest Diagnostics
         Clinical Trials' Global Account Director for GSK (or her or his
         successor or designees) prior to signing a contract or Task
         Description, who shall promptly review the request, provided that GSK
         and Quest may, through the JOC or its approved sub-committees,
         designate teams for handling certain specific types of Studies or
         Services or modify the process described in this sentence based on
         experience and with the intent of improving the process for both
         parties. The request from GSK shall follow, in order, as many
         consecutive parts of the following process as necessary to complete the
         evaluation.



         (i)      If the requested service is (a) part of the Quest Diagnostics
                  Clinical Trials standard menu of testing and services offered
                  generally to pharmaceutical industry clients or (b) a New
                  Capability that Quest Diagnostics Clinical Trials developed
                  pursuant to Section III(2)(iv) or with the mutual agreement of
                  GSK, then Quest Diagnostics Clinical Trials shall perform the
                  Service under this Agreement and in accordance with the Task
                  Description or other mutually-agreed requirements for the
                  applicable Study.

         (ii)     If the requested services cannot be performed under the option
                  provided in sub-section II(2)(i), then Quest Diagnostics
                  Clinical Trials may elect to develop a New Capability in
                  accordance with the provisions of Section III(2)(iv) or if
                  Section III(2)(iv) is not applicable, by mutual agreement of
                  the parties. Once the New Capability is developed, Quest
                  Diagnostics Clinical Trials shall perform the New Capability
                  under this Agreement and in accordance with any Task
                  Description or other mutually-agreed requirements for such
                  service.


                                       7

<PAGE>

         (iii)    If the requested services cannot be performed under the
                  options provided in sub-sections II(2)(i) and II(2)(ii) above,
                  then GSK and Quest Diagnostics Clinical Trials may look to
                  another laboratory within Quest to obtain the service(s)
                  needed by GSK (e.g., Quest's regional diagnostic laboratories,
                  Quest's Nichols Institute, Quest's Center for Applied Genomic
                  Technologies). If in such case GSK selects another Quest
                  laboratory to provide services, it shall so notify Quest
                  Diagnostics Clinical Trials, and shall negotiate a separate
                  agreement for such services with such other Quest laboratory
                  (each, an "Alternative Laboratory Agreement"), provided that
                  all revenues paid by GSK for such service(s) under such
                  Alternative Laboratory Agreement shall be counted toward
                  revenues earned by Quest for purposes of calculating the Spend
                  Targets. For the avoidance of doubt, if Quest Diagnostics
                  Clinical Trials does or would obtain referral services ("QDCT
                  Referrals") as part of the services offered generally to its
                  pharmaceutical clients (whether from a contracted referral
                  laboratory (such as the Dorevitch, Australia laboratory)
                  (each, a "QDCT Referral Laboratory") or from another Quest
                  laboratory (such as Nichols Institute)), GSK would not enter
                  into an Alternative Laboratory Agreement for such service, and
                  Quest Diagnostics Clinical Trials would perform such service
                  under sub-section II(2)(i) above and Section XIII below.

         (iv)     If the requested services cannot be performed under the
                  options provided in sub-sections II(2)(i) - (iii) above, then
                  the provisions of Section III(3) shall apply.

3.       Except as otherwise provided in Section II(2), for all services
         requested by GSK or any member of the GSK Group and performed by Quest
         Diagnostics Clinical Trials, GSK and Quest shall execute a Task
         Description as an addendum to this Agreement substantially in the form
         of Exhibit A or in such other form as may be mutually agreed by GSK and
         Quest (as amended from time to time, a "Task Description") setting
         forth, among other things, the Services to be performed by Quest
         Diagnostics Clinical Trials, the costs for such Services,
         implementation times for such Services, estimated transportation fees
         for such Study and the clinical protocol for such Study. Each Task
         Description shall apply only to the Study for which it is executed and
         shall be valid and binding upon its execution by authorized
         representatives of GSK and Quest provided, however, that GSK agrees to
         cover the cost of Services and related expenses incurred by Quest
         Diagnostics Clinical Trials in performing agreed activities on a
         specific protocol prior to completion of all required paperwork
         incident to such protocol in order to initiate the Study in accordance
         with agreed Study timelines. Any change in the scope of Services
         described in a Task Description which shall have a material effect on
         the total laboratory testing costs and/or costs or fees for other
         Services specified in such Task Description shall be set forth in a
         written amendment to such Task Description executed by authorized
         representatives of GSK and Quest, as provided in Section VII(6) below.


                                       8

<PAGE>

4.       In providing Services under this Agreement, Quest shall comply with all
         applicable governmental laws, rules and regulations, including the
         United States Clinical Laboratory Improvements Amendments (CLIA 88),
         good clinical laboratory practices, and generally accepted industry
         standards for quality assurance and quality control, and shall operate
         in accordance with all applicable regulations, standards and guidelines
         of the Food and Drug Administration and other relevant regulatory
         authorities with respect to the performance of laboratory testing for
         clinical trials and related services.

5.       Quest and GSK shall work together in good faith to promote and raise
         awareness of this Agreement within the GSK and Quest organizations
         (including conducting joint presentations within GSK and Quest), and
         shall also cooperate reasonably in the drafting and release of a press
         release announcing the Agreement's execution and other relevant
         information.

SECTION III. EXCLUSIVITY

1.       (i)      Subject to this Section III(1) and Sections III(2), III(3),
                  XXI, and XXIV, and in accordance with Section II above, GSK
                  shall exclusively use (and cause the GSK Subsidiaries to use)
                  Quest to provide Services in connection with the conduct of
                  any Study for which GSK or any GSK Subsidiary, in the ordinary
                  course of its business, would use a clinical trials central
                  laboratory. As of the date of this Agreement, GSK is required
                  to use Quest on an exclusive basis only in countries included
                  within the North American Territory or the European Territory.
                  GSK and Quest intend to review on an ongoing basis throughout
                  the Term of this Agreement Quest's ability to provide Services
                  to GSK in countries other than those included within the North
                  American Territory and the European Territory. Upon the mutual
                  agreement of GSK and Quest, additional countries may be added
                  to the scope of this Agreement, and if so added, GSK shall use
                  Quest to provide Services to it (and to any GSK Subsidiary)
                  for Studies performed in these additional countries on an
                  exclusive basis, subject to the limitations set forth in this
                  Section III, and Quest shall provide Services to GSK and any
                  GSK Subsidiary for Studies performed in such additional
                  countries pursuant to the terms of this Agreement. Similarly,
                  GSK and Quest may agree to remove countries included within
                  the definitions of the North American Territory and the
                  European Territory from the scope of this Agreement. Upon such
                  mutual agreement of GSK and Quest, GSK and any GSK Subsidiary
                  shall not be required to use Quest on an exclusive basis for
                  Studies performed in any countries removed from the scope of
                  this Agreement.

         (ii)     The exclusivity provisions of this Section III shall also
                  apply to any Contract Research Organization ("CRO") retained
                  by GSK or a GSK Subsidiary, such that for any Studies for
                  which GSK or its Subsidiary uses a CRO, GSK or its Subsidiary,
                  as appropriate, shall exclude laboratory


                                       9

<PAGE>

                  services from its contract with such CRO, and GSK or its
                  Subsidiary shall use Quest to perform the laboratory services
                  for such Study. In such a situation, Quest shall provide the
                  laboratory services for such Study and shall provide
                  laboratory results to the CRO and to GSK, as specified in the
                  Task Description for the particular Study. GSK shall have
                  responsibility for oversight of the actions of any CRO
                  retained by GSK or a GSK Subsidiary to conduct a Study for
                  which Quest performs Services under this Agreement.

         (iii)    Notwithstanding the foregoing, in the event that GSK acquires
                  any other entity or substantially all of the assets of any
                  other entity or of a business of another entity ("Acquired
                  Business"), Studies for any pharmaceutical compound conducted
                  by the Acquired Business within the North American Territory
                  or the European Territory, other than existing GSK Compounds
                  ("Acquired Business Studies"), shall be subject to the
                  exclusivity requirements of Section III only if the Acquired
                  Business Studies are initiated on or after the date which is
                  18 months after the effective date of the acquisition of the
                  Acquired Business, unless otherwise agreed by the JOC,
                  provided that any Acquired Business Studies initiated after
                  the effective date of such acquisition for which Quest
                  provides Services shall be conducted pursuant to the terms of
                  this Agreement and shall count toward satisfaction of the
                  service minimums and incentives under Section XVII, including
                  the 2002 Revenues, 2003 Revenues, AMS Targets and the TCV
                  (collectively, the "Spend Targets"). Notwithstanding the
                  foregoing, GSK and Quest shall work together in good faith and
                  to the extent practicable under the circumstances to utilize
                  Quest to provide Services in connection with Acquired Business
                  Studies prior to the end of the 18-month period after the
                  effective date of acquisition of the Acquired Business.

2.       Certain Exceptions. Notwithstanding the foregoing, the parties hereto
         agree that GSK shall not be required to use (or to cause the GSK
         Subsidiaries to use) Quest to conduct:

         (i)      any laboratory testing required by any of GSK's or a GSK
                  Subsidiary's clinical pharmacology units in connection with
                  any Study, including the units currently located at
                  Presbyterian Medical Center in Philadelphia, Pennsylvania, at
                  GSK's facilities in Harlow, England, and at Addenbrookes
                  Hospital in Cambridge, England, or of any similar clinical
                  pharmacology units under the direct management of GSK
                  established during the Term, or any clinical pharmacology
                  testing in connection with a Study which has been
                  subcontracted out to an investigator, clinical research
                  organization, hospital or similar entity, provided that all
                  other central laboratory Services for such Study shall be
                  performed by Quest subject to the exceptions set forth in (ii)
                  through (x) below;


                                       10

<PAGE>

         (ii)     any assay for the DMPK of pharmaceutical compounds or any
                  genotypic or genomic assay which GSK performs internally or by
                  using a GSK Affiliate;

         (iii)    for any Study which is being conducted as of the date hereof
                  (or in the case of an GSK Subsidiary acquired after the date
                  hereof, for any Study which is being conducted as of the date
                  of such acquisition or initiated prior to the date which is 18
                  months thereafter), any laboratory testing which is conducted
                  as part of that Study by Persons other than Quest, provided
                  that Studies conducted by Acquired Businesses shall be subject
                  to Section III(1)(iii);

         (iv)     any testing in connection with a Study to the extent that such
                  testing is not offered by Quest or is performed using a
                  methodology that is not acceptable to GSK or requires rapid
                  turn-around time that Quest cannot provide, including
                  microbiology testing (a "New Capability"); provided, however,
                  that in order for the provisions of this Section III(2) to
                  apply, GSK shall have first (a) followed the provisions of
                  Section IV(3)(ii) and (b) followed the provisions set forth in
                  Section II(2). It is understood that Quest needs at least
                  three months advance notice to implement new testing
                  capabilities, and that GSK shall use reasonable efforts to
                  notify Quest at a sufficiently early stage (no less than three
                  months prior to Study initiation, to allow full validation and
                  set up of the desired test(s)). If it is impracticable for GSK
                  to give Quest at least 3 months advance notice of the need,
                  then GSK may use another lab to meet those testing needs for
                  that Study if Quest elects not to (or cannot) develop and
                  validate in a fashion satisfactory to GSK the New Capability
                  within GSK's required timeline and if such lab can meet such
                  testing needs. If GSK needs such testing capabilities for a
                  future Study, the process outlined above shall be followed
                  again if it has been more than six months since the last time
                  GSK has been through such process and provided further that if
                  Quest expands its capabilities to add a New Capability that
                  meets GSK requirements, or to meet the rapid turnaround time
                  required for such Study, GSK shall award work on subsequent
                  Studies involving such testing to Quest;

         (v)      any testing in connection with a Study that is usually
                  performed by the Investigators participating in a Study;

         (vi)     any Study funded by a Person, in whole or in part, other than
                  GSK or a GSK Affiliate, where use of a laboratory other than
                  Quest is required by that Person; provided, however, that GSK
                  shall use reasonable commercial efforts to have Quest engaged
                  to perform Services in connection with the conduct of any
                  Studies required in the course of such research and
                  development;

         (vii)    any Phase IV Study in the European Territory which is
                  performed by a local clinical lab and which is not centrally
                  funded by GSK;


                                       11

<PAGE>

         (viii)   any Study conducted in connection with GSK's (or any GSK
                  Affiliate's) research and development activities undertaken
                  pursuant to any co-development, co-promotion, collaborative
                  research, licensing or similar agreement with a third party
                  which is not an Affiliate Controlled by GSK (e.g., joint
                  ventures, partnerships, licensing or co-development contracts)
                  where use of a laboratory other than Quest is required by that
                  Person, except for Studies conducted by GSK for diaDexus LLC;
                  provided, however, that GSK shall use reasonable commercial
                  best efforts to have Quest engaged to perform Services in
                  connection with the conduct of any Studies required in the
                  course of such research and development;

         (ix)     any Study which requires in GSK's good faith judgment, the
                  involvement of a national or international "key opinion
                  leader" in a specified role in providing some or all of the
                  Services for a Study (for example, use of an internationally
                  prominent pathologist in reading certain types of specialized
                  or unusual pathology slides), and where Quest is unable or
                  elects not to use the key opinion leader in such designated
                  role;

         (x)      any Study for a consumer healthcare product, such as an
                  over-the-counter drug; and

         (xi)     any Other Study.

         Notwithstanding the foregoing exceptions to the exclusivity
requirements, if Quest Diagnostics Clinical Trials is engaged to perform
Services in connection with any such Studies, including without limitation
through the use of QDCT Referrals (as provided in Section II(2) above), such
Studies shall be conducted pursuant to the terms of this Agreement, and the
revenues paid to Quest Diagnostics Clinical Trials (including those for the QDCT
Referrals) for such Services shall count toward satisfaction of the Spend
Targets.

3.       Should Quest decline to perform Services in connection with any Study
         after GSK has followed the provisions of Section II(2) and complied
         with any applicable requirements of Section III(2)(iv), then GSK or the
         GSK Subsidiary shall be free to use a clinical laboratory other than
         Quest to perform the Services in connection with such Study. In the
         event that GSK requests Services of Quest Diagnostics Clinical Trials,
         whether or not subject to the exclusivity requirements, that are (a)
         part of Quest Diagnostics Clinical Trials standard menu of testing and
         services offered generally to pharmaceutical industry clients or (b) a
         New Capability Quest Diagnostics Clinical Trials has developed pursuant
         to Section III(2)(iv) and Quest elects not to perform such Services for
         GSK, then the applicable Spend Targets shall be reduced by 70% of the
         amount reasonably paid by GSK to another lab for the work at issue;
         provided that Quest shall not be penalized for Inadvertent or De
         Minimis Breaches of its obligation to perform Services and provided
         further that in order to provide for a transition period the parties
         agree that Quest shall not be penalized under this Section III(3) for


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<PAGE>

         breaches of any requirement to perform Services requested by GSK after
         the execution of this Agreement that occur on or prior to June 30,
         2003.

4.       In the event that GSK uses another lab to perform Services in violation
         of the exclusivity requirements set forth in this Section III, GSK
         shall pay to Quest an amount equal to 70% of the amount reasonably paid
         by GSK to the other lab for the Services at issue, provided that GSK
         shall not be penalized for Inadvertent or De Minimis Breaches of its
         exclusivity obligation and provided further that in order to provide
         for a transition period the parties agree that GSK shall not be
         penalized for breaches of its exclusivity obligation which occur on or
         prior to June 30, 2003. Any payments made pursuant to this Section
         III(4) shall not count toward the applicable Spend Targets.

SECTION IV. RELATIONSHIP MANAGEMENT

1.       Quest shall designate individuals employed by Quest who are approved by
         GSK to be located at GSK's facilities in Upper Providence,
         Pennsylvania, Collegeville, Pennsylvania, and Harlow, England, or at
         such other locations as may be mutually agreed by GSK and Quest, to act
         as liaison and relationship managers between Quest Diagnostics Clinical
         Trials and GSK's Clinical Research and Development department.

2.       Within thirty days of the date of this Agreement, GSK and Quest shall
         form a joint operating committee (the "JOC") that shall have oversight
         responsibility for the parties' performance of their respective
         obligations under this Agreement and the relationship between the
         parties. The JOC shall be composed of at least two representatives each
         appointed by Quest and GSK, respectively. GSK and Quest may
         mutually-agree to include within the JOC representatives from any CRO
         routinely used by GSK for the performance of Studies. The JOC will be
         co-chaired by Quest Diagnostics' VP, Pharmaceutical Services and GSK's
         Vice President, Global Clinical Operations. The JOC may create such
         subcommittees consisting of representatives of each party as it
         determines to be necessary or prudent.

3.       The JOC shall conduct quarterly performance and business review
         meetings, at a location to be mutually agreed by GSK and Quest,
         provided that the JOC shall meet more often if requested by either
         party. The JOC shall, among other things:

         (i)      review annual budget and quarterly forecasts for Services
                  under this Agreement and identify Studies that will be
                  starting within the following three to six months that GSK
                  identifies as Pivotal (for purposes of this Agreement,
                  "Pivotal" shall mean that the identified Study is either (a)
                  of significant strategic importance to GSK or (b) designated
                  as "pivotal" under the Food and Drug Administration's New Drug
                  Application process);


                                       13

<PAGE>

         (ii)     prospectively identify and plan GSK turn around time and
                  capability needs (including investment requirements) to permit
                  Quest a reasonable amount of time (A) to evaluate the needed
                  capability and (B) to develop and implement the capability (if
                  Quest decides to do so). To the extent practicable, such
                  review shall take place a minimum of six (6) months prior to
                  GSK's anticipated need, provided that if GSK has not defined
                  its anticipated needs at such time, GSK will use
                  commercially-reasonable efforts to notify Quest of its
                  anticipated needs promptly after those needs are identified
                  and defined and permit Quest a commercially-reasonable time to
                  determine whether it will develop the capability;

         (iii)    be responsible to resolve escalated, significant contract
                  issues, including, without limitation, exclusivity violations
                  and performance metric issues in accordance with Section IV(6)
                  below, and determining capability needs;

         (iv)     on an annual basis, review the performance metrics set forth
                  in Section VI, and if necessary, modify or redefine the
                  performance metrics;

         (v)      on an annual basis, review a list of all GSK collaborative and
                  co-development projects;

         (vi)     determine the application of exclusivity under Section
                  III(2)(iv), and (viii) and the timing of exclusivity under
                  Section III(1)(iii) and Section XXIV;

         (vii)    review pricing for "Custom Tests" upon request of either
                  party;

         (viii)   review Quest Diagnostics Clinical Trials' standard menu of
                  testing and services on an annual basis, including any
                  additions made since the previous review; and

         (ix)     discuss any other issues arising under this Agreement.

4.       At any time GSK believes that Quest is failing to provide Services
         pursuant to the terms of this Agreement, GSK may convene a meeting of
         the JOC to discuss such failures at a location to be mutually agreed by
         GSK and Quest as promptly as practical after GSK notifies Quest of the
         request to have such meeting. The attendees of such meetings shall be
         mutually agreed by GSK and Quest.

5.       Likewise, at any time Quest believes that GSK is failing to perform its
         obligations pursuant to the terms of this Agreement, Quest may convene
         a meeting of the JOC to discuss such failures at a location to be
         mutually agreed by GSK and Quest as promptly as practical after Quest
         notifies GSK of the request to have such meeting. The attendees of such
         meetings shall be mutually agreed by GSK and Quest.

6.       Either party may refer unresolved issues to the JOC in accordance with
         procedures developed therefor by the JOC or (until such procedures are
         developed) by notifying both the GSK and Quest leaders of the JOC in
         writing of


                                       14

<PAGE>

         the issue or convening a meeting under Sections IV(4) and IV(5) above.
         GSK and Quest shall ensure that their respective representatives on the
         JOC meet promptly thereafter to attempt to resolve the issue. If the
         JOC cannot resolve the issue within thirty (30) days after receiving
         notice thereof, it will promptly notify both Quest's Senior Vice
         President, Advanced Diagnostics and GSK's Senior Vice President,
         Clinical Development and Medical Affairs in writing of the dispute and
         the JOC's efforts to resolve it. The JOC may elect to notify such
         executives in less than 30 days if the JOC agrees that further attempts
         at resolution by the JOC will be futile. If such executives are unable
         to resolve the dispute within 60 days after receipt of notice by the
         JOC, the aggrieved party may, as applicable, proceed under Section XXI
         or XXII of this Agreement and enforce the Agreement under Section
         XXVIII.

SECTION V. REVIEW AND IMPROVEMENT OF SERVICES

1.       The parties hereto acknowledge and agree that (a) the pharmaceutical
         industry and clinical trials industry frequently undergo change,
         including technological advancements in connection with the conduct of
         Studies and abilities to communicate the results of the Studies, and
         (b) the parties hereto intend the performance by Quest of Services
         under this Agreement to reflect the improvements available as a result
         of such changes.

2.       The JOC shall meet at least one time annually to review the terms of
         this Agreement which govern the Services provided by Quest hereunder,
         including Sections III and VIII through Section XVI, and to negotiate
         in good faith amendments to this Agreement to be executed and delivered
         by the parties hereto providing for quality and cycle time improvements
         and other changes in such Services in response to technological,
         operational or other advancements or changes. It is acknowledged and
         agreed that, among other things, Quest may be required to invest in new
         equipment and staff as a result of such amendments, and that to fund
         such investments, Quest may be required to raise prices for affected
         Services consistent with this Agreement.

SECTION VI. CERTAIN PERFORMANCE METRICS AND MEASURES

1.       With respect to any Study, Quest shall provide any Services required
         pursuant to this Agreement for such Study within the relevant
         implementation time specified in Exhibit D, as Exhibit D may be amended
         from time to time pursuant to Sections V or XXIII; provided, however,
         that, with respect to any Study, to the extent an implementation time
         for any Service is expressly set forth in a Task Description, Quest
         shall provide such Service for such Study within the implementation
         time set forth in such Task Description. In the event Exhibit D is
         amended, such that the amendment causes an increase in the costs of
         Quest's performance of Services hereunder, Quest and GSK shall
         negotiate an


                                       15

<PAGE>

         appropriate price adjustment under this Agreement with respect to the
         amended item(s) only.

2.       With respect to each Study, Quest shall maintain a system to monitor
         and measure its compliance with the performance metrics and measures
         set forth in Exhibit D or in the Task Description for such Study and
         shall provide GSK a monthly written report regarding compliance with
         such metrics and measures. Quest shall provide GSK with reasonable
         access to the data underlying such monthly compliance reports for
         verification purposes.

SECTION VII. STUDY PREPARATION PHASE

1.       In preparing for any Study, GSK and Quest shall work in accordance with
         the guidelines defined in the GSK-Quest "Study Set-up Handbook" (the
         "Handbook") For each Study, GSK shall provide a final, approved
         protocol to Quest before CLW approval.

2.       In order to obtain an early indication of the central laboratory
         costings, a GSK Study Leader may submit a completed laboratory
         assumptions document to Quest; within five (5) days after receipt
         thereof, Quest will provide a preliminary budget to the GSK Study
         Leader. After approval of the CLW and within ten (10) days after
         receipt of a Request for Proposal from GSK, Quest shall provide to GSK
         a good faith estimate based on current information of all costs
         associated with a Study. Four weeks before any Study is scheduled to
         begin, Quest will provide a cost proposal, based on the final approved
         protocol for the Study, to the designated GSK Clinical Study Leader
         (with a copy to the GSK Global Resourcing, Grants and Contracts Group)
         in the form of a Task Description. All anticipated costs must be
         estimated, including dry ice, translations, reporting costs and storage
         and transportation costs. Each of GSK and Quest shall use its
         reasonable best efforts to agree on the costs for the Study and to sign
         the Task Description prior to the Study start date. If GSK makes any
         subsequent changes to the final approved protocol that impact the costs
         of the Study significantly, GSK shall bear such additional costs;
         provided, however, that the additional costs are reasonable and are
         itemized for GSK in reasonable detail. In such a situation, Quest shall
         incur no additional costs without the prior approval of GSK; provided,
         however, that Quest may incur reasonable, additional costs if it is
         unable promptly to obtain GSK's approval to such additional costs and
         the nature of the Study and requirements for timely performance of
         Services require Quest immediately to incur such reasonable, additional
         costs.

3.       Prior to the initiation of each Study, GSK shall provide Quest with a
         copy of all appropriate, approved protocols, amendments and
         modifications and other necessary information, provided that in no
         event shall Quest have access to patient identifiable information where
         disclosure would be contrary to privacy laws or regulations or GSK
         privacy policy. Quest will not modify or change such information
         without the prior written consent of GSK.


                                       16

<PAGE>

4.       If the laboratory requirements for a Study involve the extraction of
         DNA from a patient's specimen, it is the responsibility of the GSK
         Clinical Study Leader, as the Study is being set up, to provide the
         Quest Project Leader with the master patient informed consent covering
         DNA analysis (if not specified in the protocol for such Study). Quest
         shall not extract DNA from any specimen unless the patient informed
         consent has been signed, as confirmed to Quest by that patient's
         investigator. Quest shall follow GSK's instructions with regard to
         adherence to GSK's patient informed consent policy, including
         destroying specimens if requested by GSK. Quest will include all
         necessary collection supplies in the laboratory test kits.

5.       No later than four weeks before the beginning of a Study, a CLW will be
         completed by representatives from GSK and Quest and approved by GSK.
         Provided that GSK has specified translation/language requirements in
         the CLW, no later than two weeks before the beginning of a Study, Quest
         will demonstrate to GSK its ability to communicate fluently with
         Investigators for such Study and, if necessary, will specify to GSK the
         languages used to communicate with the Investigators in the relevant
         CLW. Quest shall ship supplies for the Investigators in order to arrive
         at the Investigator sites not later than the date requested by GSK.

6.       If any significant changes are made to a Study's protocol or central
         laboratory worksheet (CLW) following GSK approval of the CLW that
         require additional work or resources not included in the original cost
         proposal for the Study, such changes shall be charged to GSK in
         accordance with Exhibit F (Minimum Charges), attached hereto and
         incorporated herein, provided, however, that (a) upon request of GSK,
         Quest shall provide reasonable supporting documentation for the fees in
         Exhibit F and (b) that the favorable pricing provisions of Sections
         XV(1) and XV(2) shall apply to the charges in Exhibit F. Further, GSK
         shall provide a formal request to Quest to prepare and submit a Change
         in Scope form to address such changes. Quest shall be responsible for
         the preparation of an accurate, properly executed Change In Scope form,
         in the form of Exhibit G, attached hereto and incorporated herein, for
         any such change(s) in the Study's protocol or CLW. Significant changes
         made to a Study's protocol or CLW by GSK after a schedule has been
         determined which necessitate additional programming time or changing of
         kit contents by Quest, shall be made at GSK's expense; provided,
         however, that the additional charges are reasonable and are itemized
         for GSK in reasonable detail if not already specified in Exhibit F.
         Quest shall incur no additional costs without the prior approval of
         GSK; provided, however, that Quest may incur reasonable, additional
         costs if it is unable promptly to obtain GSK's approval to such
         additional costs and the nature of the Study and requirements for
         timely performance of Services require Quest immediately to incur such
         reasonable, additional costs. For the avoidance of doubt, all minimum
         charges or administrative charges paid by GSK under this Agreement to
         Quest or its subcontractors shall count as revenues earned by Quest
         under this Agreement.


                                       17

<PAGE>

         In the event GSK makes any significant changes after CLW approval as
         described above for any Study, Quest shall use its reasonable best
         efforts to ship supplies for the Investigators in order to arrive at
         the Investigator sites not later than the date requested by GSK;
         however, GSK understands that significant changes to a Study may delay
         supply delivery beyond the original date requested. Any additional
         shipping charges incurred by Quest to comply with this obligation shall
         be the responsibility of GSK.

7.       Investigator meetings are intended to assist in the orientation of
         Investigators and their staff assigned to a Study with respect to the
         laboratory procedures contained in the Investigator Manual, and the
         performance of other Services as may be required by the relevant CLW.

         Quest shall provide a representative at the GSK-sponsored Investigator
         meeting to review specimen preparation, packaging and transportation
         requirements. In the European Territory, Quest shall participate in
         Investigator meetings at locations and at times specified by GSK upon
         two weeks' prior notice. In the North American Territory, Quest shall
         participate in Investigator meetings at locations and at times
         specified in the relevant CLW.

         Provided that GSK has approved the CLW for any applicable Study, Quest
         will provide customized presentation materials for the applicable
         Investigator meeting upon two weeks' prior notice from GSK.

         Upon request by GSK, Quest will provide to GSK for review and comment
         in advance of the Investigator meeting copies of the materials to be
         presented at such meeting and will make any factual corrections
         requested by GSK at no charge to GSK.

         If Quest is not given two weeks' prior notice, additional reasonable
         charges will apply for (a) Quest's preparation of customized meeting
         materials and (b) revisions to customized meeting materials resulting
         from changes in GSK's protocol or other changes specified by GSK to
         Quest; provided, however, that the expenses underlying such additional
         changes are itemized for GSK in reasonable detail if not already
         specified in Exhibit F.

8.       For Services provided in the North American Territory, Quest will
         prepare and distribute to each Investigator a protocol-specific
         Investigator Manual. In addition, laminated pictograms are available
         for an additional charge. The purpose of the Investigator Manual and
         Investigator (Lab Requirement) Summary is to provide the Investigator
         and the Investigator's staff with precise instructions concerning
         specimen collection, transport and reporting. In the North American
         Territory, the Investigator Manual shall be provided in English,
         Spanish and French; the last two languages will be available two weeks
         after approval of the English Investigator Manual.


                                       18

<PAGE>

         In the European Territory, Quest will prepare and distribute to each
         Investigator a customized Investigator Manual. In addition, laminated
         pictograms are available for an additional charge. The Investigator
         Manual shall be prepared for approval in English, and available in
         French, Spanish, Italian, German and Dutch, and in such additional
         languages requested by GSK two weeks after approval of the English
         Investigator Manual. Upon written request from GSK, Quest will
         translate the Investigator Manual and/or Investigator (Lab Requirement)
         Summary into other languages for an additional charge per language.

         For any additional countries that may be added to this Agreement, Quest
         will provide the Investigator Manual and/or the Investigator (Lab
         Requirement) Summary and/or pictogram in languages as specified in the
         Task Description for the particular Study. Quest shall provide such
         materials in English, French, Spanish, Italian, German, and Dutch at no
         additional charge, and GSK and Quest shall negotiate in good faith the
         costs of any translations into other languages required by GSK.

         Quest shall use its reasonable best efforts to provide such additional
         translations within two weeks of request.

9.       Upon request from GSK, Quest will provide telephone in-service training
         to staff at clinical study sites at no additional charge to GSK. Upon
         request and with two weeks' prior notification from GSK, Quest will
         provide on-site field service training for protocol initiation and/or
         ongoing support. Costs associated with this Service (an additional
         charge per day plus travel and accommodation expenses) shall be the
         responsibility of GSK.

         Quest will make available, upon GSK's request, professional laboratory
         consulting services at GSK and/or Investigator sites beyond those
         consulting services generally provided by Quest in connection with a
         Study. Any costs associated with these services shall be agreed to in
         advance by Quest and GSK.

10.      Quest will provide GSK with technical support Services, including
         provision of data transmission and test codes and remark codes, when
         appropriate. Quest, with input from GSK, will develop a standard format
         for data transmission and will create datasets prior to the initiation
         of a Study to transmit records. Quest shall monitor data to ensure
         trouble-free transmission to BDS. Quest must confirm to GSK that all
         data management systems required for any Study are in place or shall be
         in place, prior to the commencement of such Study. The costs for any
         data programming requested by GSK over and above Quest's usual
         programming and technical Services provided to GSK shall be reimbursed
         by GSK; provided, however, that Quest shall provide GSK with an
         itemization of such costs prior to implementing any programming
         changes.

11.      Quest will make available from time to time, for GSK's convenience as a
         supplemental means of accessing certain information, Quest's
         ResultView(TM) web site and associated software (cumulatively, the
         "Site"). Quest does not promise


                                       19

<PAGE>

         that the Site will be available at all times or at any particular time
         and may elect to discontinue the Site or GSK's access to it at any
         time, with or without notice. To the extent that GSK requests
         additional services beyond Quest's standard support services, such
         services (if available) will incur additional charges as set forth in
         Exhibit E.

         (i)      GSK shall provide Quest with a list of authorized employees,
                  agents, and subcontractors, if any, having a legitimate
                  business need for access to the Site for whom GSK requests
                  such access (each a "GSK Authorized User"). GSK shall notify
                  Quest promptly to remove access for any GSK Authorized User
                  who ceases to be an employee, agent, or subcontractor of GSK,
                  who is reassigned by GSK so as not to have a legitimate
                  business need for such access, or for whom such access
                  otherwise should be removed.

         (ii)     All persons who access the Site (including each GSK Authorized
                  User) will be required to accept certain conditions governing
                  such person's use of the Site before access to the Site is
                  permitted by Quest (the "User Agreement"). GSK shall be fully
                  responsible for each GSK Authorized User's compliance with the
                  User Agreement and for all other acts and omissions of each
                  GSK Authorized User relating to the Site. Without limiting the
                  foregoing, GSK and each GSK Authorized User shall cooperate
                  with Quest in protecting the security of the Site as set forth
                  more fully in the User Agreement, and Quest shall have the
                  right to deny access to any GSK Authorized User as provided in
                  the User Agreement.

         (iii)    Subject to this Agreement and in conformity with the User
                  Agreement, a GSK Authorized User may, at the sole risk and
                  responsibility of GSK acting through such GSK Authorized User
                  and solely for the lawful, professional use of GSK acting
                  through such GSK Authorized User, display the Site on a web
                  browser and print portions of the Site that are of
                  professional interest to GSK acting through such GSK
                  Authorized User, for informational purposes only. Otherwise,
                  neither GSK nor any GSK Authorized User is licensed to display
                  or print the Site. In addition, neither GSK nor any GSK
                  Authorized User shall, in whole or in part, reproduce,
                  distribute, create derivative works from, reverse engineer,
                  decompile, disassemble, sell, or sublicense any material on
                  the Site.

         (iv)     Notwithstanding anything to the contrary in this Agreement,
                  and subject to the rights of third-party licensors and GSK's
                  rights to Study data contained in Section XVIII hereof, Quest
                  or its affiliates own all copyright, trademark, patent, trade
                  secret, and other intellectual property and proprietary rights
                  in the Site, in all media now known or later devised. GSK
                  shall not remove, conceal, or alter any copyright notice,
                  disclaimer, or other notice. In addition, the rights of Quest
                  or its affiliates shall include all right, title, and interest
                  in and to any aggregate data (other than Study data) derived
                  from the Site (such as usage patterns) and Quest and its
                  affiliates reserve


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<PAGE>

                  the right to use for any lawful purpose any such data
                  collected from or relating to any use of the Site by GSK or
                  any GSK Authorized User.

         (v)      GSK ACKNOWLEDGES AND AGREES THAT THE MATERIAL ON THE SITE IS
                  FOR INFORMATIONAL PURPOSES ONLY AND THAT NO TEST RESULTS OR
                  OTHER MATERIAL ON THE SITE SHOULD BE RELIED ON IN ANY
                  SUBMISSION TO THE UNITED STATES FOOD AND DRUG ADMINISTRATION
                  OR ANY OTHER REGULATORY BODY. GSK FURTHER ACKNOWLEDGES AND
                  AGREES THAT THE SITE IS PROVIDED "AS IS," WITH ALL FAULTS.
                  QUEST DISCLAIMS, TO THE MAXIMUM EXTENT PERMITTED BY LAW, ANY
                  AND ALL REPRESENTATIONS AND WARRANTIES, EXPRESS OR IMPLIED, IN
                  ANY WAY RELATING TO THE SITE, INCLUDING WARRANTIES OF
                  MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE,
                  WARRANTIES AGAINST INFRINGEMENT OR OF QUIET ENJOYMENT, AND
                  WARRANTIES OF ACCURACY OR COMPLETENESS. QUEST SHALL HAVE NO
                  LIABILITY, DIRECT OR INDIRECT, TO GSK OR ANY OTHER PERSON
                  BASED ON OR OTHERWISE IN ANY WAY RELATING TO THE SITE.

SECTION VIII. STUDY MANAGEMENT

1.       The Quest Project Leader for any Study will interact on a regular basis
         with the GSK Clinical Study Leader or other designated GSK contact who
         shall be specified in each Task Description. Quest shall use its
         reasonable best efforts to retain such administrator's services for the
         length of each Study to which they have been assigned, in order to
         maintain the quality and consistency of Services. In addition, Quest
         shall provide a qualified back-up to such Project Leader. If such
         administrator's responsibilities change during the course of a Task
         Description, Quest shall notify the designated GSK contact of such
         change. Quest shall ensure that the level, quality and continuity of
         Services are maintained at the levels required by this Agreement
         despite any changes in personnel at Quest. The regional Quest Medical
         and Regulatory Affairs representative (or his or her designee) will use
         reasonable best efforts to review all concept or draft protocols at
         least 12 weeks prior to start of the Study (where made available by
         GSK) and comment on clinical testing, methodologies, sample
         collection/handling and sample stability. Where requested by GSK, Quest
         Scientific Affairs will obtain the input of Quest Diagnostics Academic
         Associates, Nichols Institute Scientists/Medical Directors and Nichols
         Institute Diagnostics personnel and use reasonable best efforts to
         provide any appropriate recommendations for improvements to the GSK
         Clinical Study Leader within 10 working days.

2.       Quest will provide to GSK and Investigators a toll-free telephone
         number for answering questions related to the Services. Quest shall
         also provide to GSK


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<PAGE>

         and Investigators the names and telephone numbers of Quest contacts who
         can answer testing related questions and take orders for supplies.

3.       For Studies in the European Territory, Quest will provide sufficient
         personnel to communicate with Investigators and GSK personnel in
         English, French, Spanish, Italian, German and Dutch, as need be
         depending on the language requirements of the country in which the
         particular Study is performed. For Studies in both the North American
         and European Territories, Quest will provide GSK with access to a staff
         pathologist or an appropriately qualified Ph.D.- or M.D.-level staff
         member.

4.       Quest technical support will be provided to interact with GSK and any
         GSK designated GSK agent or subcontractor for problem resolution. Quest
         will use its reasonable best efforts to resolve any technical errors
         promptly upon identification of the problem.

SECTION IX. SPECIMEN TRANSPORT

1.       In the contiguous United States and as appropriate based on individual
         study requirements, Quest generally provides courier service to
         clinical trials clients through its proprietary courier network at no
         charge. Outside the contiguous United States, Quest generally provides
         courier service to clinical trials clients through contracted carriers
         (e.g., Federal Express, DHL) at actual charges plus 10%. Quest will
         provide for courier service for shipment of specimens from an
         Investigator to Quest, the costs, timing and service provider of which
         shall be as mutually agreed by Quest and GSK, based upon the
         requirements specified in the relevant CLW. In any event, Quest shall
         use its reasonable best efforts to provide courier service to
         Investigators on weekends or holidays in the event of an unanticipated
         patient visit. Quest shall indicate to the GSK Clinical Study Leader or
         other designated GSK contact any limitations on courier service which
         would impede proper and/or timely collection and delivery of supplies
         or specimens.

2.       Quest will provide a tracking system to ensure pick up at Study sites
         and delivery to Quest in line with the specifications required and
         agreed to by protocol and reflected in the Task Description for a
         particular Study. The tracking system shall be that which was in place
         at SmithKline Beecham Clinical Laboratories, with such modifications as
         Quest has made or may make to the system after the date of this
         Agreement to provide specimen pick up Services in both the North
         American and European Territories. Such tracking system will be
         available to GSK upon request. Any requests by GSK for tracking of
         specimens in excess of the usual tracking system provided by Quest in
         the North American and European Territories shall be discussed and
         agreed to by the parties. Additional costs, if any, associated with the
         excess tracking requirements, will be charged to GSK and agreed upon
         between GSK and Quest.


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<PAGE>

3.       From the point of pick up of specimens from the Investigator by a
         courier employed by Quest under any Task Description, Quest shall
         ensure that all shipping, handling, storage and disposal of specimens
         shall be in accordance with any and all applicable rules and
         regulations.

4.       Quest shall be compensated at actual cost plus 10% for emergency
         delivery and/or transportation Services authorized in writing by GSK
         which are not included in the agreed to price on the applicable Task
         Description.

5.       Quest may be required to provide for shipment of specimens from Quest
         to other laboratories or to GSK locations as described in the Task
         Description. Quest shall ensure that shipping methods and documentation
         for clinical sample shipments shall be in accordance with any and all
         applicable rules and regulations, and in compliance with guidelines set
         forth by the courier service. In addition, Quest shall be prepared to
         receive and analyze specimens that are referred by GSK to Quest from
         other laboratories.

6.       If requested by GSK, Quest may be required to send Referral Specimens
         to other laboratories for analysis. Quest shall be responsible for
         obtaining, handling, shipping and reporting Referral Specimens in
         accordance with any and all applicable rules and regulations. Quest
         will bill GSK for the cost of testing Referral Specimens (which is the
         amount Quest is billed by the referral laboratory) plus a referral
         service fee per specimen. This referral service fee includes specimen
         transport from the Investigator sites to Quest in the North American
         Territory, specimen referral (including specimen tracking and
         transport), and results reporting to GSK. In the European Territory,
         inbound transportation costs will be agreed with GSK. Any fee increase
         imposed by the referral laboratory will be passed on to GSK.

7.       Archival Specimens shall be stored and maintained by Quest for the
         length of time and under storage conditions as described in the CLW for
         the fees described in Section XV(15). Archival Specimens may be shipped
         to GSK or to others as specified in the relevant CLW or as otherwise
         requested by the designated GSK contact. Labeling requirements for
         Archival Specimens to be returned to GSK shall be specified in each
         CLW.

8.       If requested by GSK, Quest will be required to send any DMPK specimens
         received by Quest in extended storage to other laboratories for
         analysis ("DMPK Specimens"). Quest will be responsible for handling and
         shipping DMPK Specimens. Quest will bill GSK for the cost of storage as
         detailed in the applicable Task Description; unless Quest's proprietary
         courier network is used for transportation of the DMPK Specimens, all
         inbound and outbound transportation costs will be charged to GSK at
         actual cost plus 10%. DMPK specimens shipped to Quest designated for
         extended storage shall be stored and maintained by Quest for the length
         of time and under storage conditions as described in the relevant CLW.


                                       23

<PAGE>

SECTION X. RESULT REPORTS

1.       Quest shall complete test assays upon specimens received from
         Investigators and shall compile patient demographic data which
         accompanied such specimens. Results of test assays and patient
         demographic data will be reported to Investigators and GSK with the
         data specified, by the method and with the frequency of transmission
         and turnaround as set forth in the relevant CLW, or as otherwise
         requested by GSK. Examples of standard reports are available to GSK
         upon request. Additional reports requested by GSK, which require fields
         of data not specified in the original CLW, will be provided at an
         additional reasonable charge to GSK.

2.       Upon request and as directed by GSK, Quest will implement any or all of
         the following report format and flagging options: (i) delta flags; (ii)
         blinded results; (iii) clinical significance summary; (iv) quick trend
         summary; (v) toxicity grading; and (vi) report header and footer text,
         and any additional format and flagging options requested by GSK. If GSK
         requests a format or flagging which requires significant customization
         of Quest's standard report format and flagging options, GSK and Quest
         shall negotiate in good faith an additional reasonable charge to GSK
         for such request.

3.       The following Service options apply to report delivery to the
         Investigators and GSK:

         Within the North American Territory: One hard copy result report will
         be delivered via fax and one will be delivered via U.S. mail. GSK and
         Quest shall negotiate in good faith the costs of any alternate
         reporting fashion requested by GSK.

         From the North American Territory to a Destination Outside the North
         American Territory: One result report will be transmitted via facsimile
         plus one hard copy report will be sent via standard postal service per
         visit for countries other than the North American Territory.

         From the United Kingdom to a Destination within the European Territory:
         One result report will be transmitted via facsimile plus one hard copy
         report will be sent via standard postal service per visit.

         Other: GSK may request overnight express report delivery, or multiple
         modes of delivery, at an additional charge for any of the reports
         described above. The parties hereto acknowledge and agree that as
         improved technology becomes reasonably available, Quest will make
         available "real-time" communication or other electronic communication
         between and among Quest, GSK and the Investigators.

         Unless otherwise specifically agreed in writing between the parties,
         charges for hard-copy lab reporting (other than the original report, as
         to which there is no charge) shall be as set forth in Exhibit H.


                                       24

<PAGE>

SECTION XI. DATA MANAGEMENT REQUIREMENTS

1.       Quest shall perform edit checks on patient demographic data (consistent
         with privacy laws and regulations) on the day that the sample is
         received. If Quest detects errors or omissions, including an invalid
         Study number, an invalid Investigator number, an invalid Investigator
         site number, an invalid patient number, an improper visit sequencing,
         or patient demographics that changed from a previous visit, then Quest
         shall contact the Investigators by telephone (or other mutually
         acceptable method of communication) for resolution. A record of all
         such changes shall be maintained by Quest. If Quest is unable to
         contact the Investigators or has been unable to reach a resolution
         within five business days (or within two business days if after the
         last patient visit), then Quest shall notify the designated GSK
         contact.

2.       Quest shall telephone the Investigators to notify them of lab assay
         values which must be made known immediately to the Investigator (and
         any medical monitors designated in the Task Description) for proper
         patient care and which are defined in the relevant CLW (hereinafter
         "Alerts"). In addition, Quest shall immediately provide notification to
         the Investigator and medical monitor of lab assay values which would
         exclude the patient from the Study and which are defined in each
         clinical protocol if requested in the relevant CLW. Quest shall notify
         Investigator sites within one working day (limited to Monday through
         Friday) of the completion of testing, or as specified in the CLW. If
         Quest is unable to reach the Investigator after Quest has made a
         minimum of two attempts, Quest shall promptly notify the GSK Clinical
         Study Leader, medical monitor or other designated GSK contact. All
         Alerts shall be automatically flagged on the hard copy laboratory
         report.

3.       Quest shall provide to GSK a support service for queries or resolving
         errors related to Quest, with such queries or errors to be resolved
         within three days (or within 24 hours if after the last patient visit).
         Quest also shall provide guidance for any general lab questions and
         shall ensure the complete resolution of all data issues at the
         completion of the Study (ensuring satisfactory completion of the
         relevant Study). Quest shall track all queries raised in each Study,
         provided that GSK has entered such queries in the relevant database
         established by GSK.

4.       Quest will retain all patient records and test results from any Study
         for five years following the termination of each Study or for such
         longer period as specified in the Task Description for a Study or for
         such longer period as required by applicable laws or regulations. Quest
         shall maintain all specimens from a Study following the termination of
         the Study for the period specified in the Task Description for a Study
         or for such longer period of time as required by applicable law or
         regulations. Upon GSK's request, Quest shall return any specimens or
         data from a Study to GSK, at an additional charge to be agreed upon by
         GSK and Quest. GSK and Quest shall agree on long-term specimen
         retention and specimen destruction on a Study-by-Study basis. Quest
         shall comply with all data and specimen retention methods established
         by relevant regulatory authorities. GSK shall advise Quest in writing
         of data or specimen retention


                                       25

<PAGE>

         requirements in excess of these standards, and Quest will use its
         reasonable best efforts to accommodate GSK's requirements. Additional
         reasonable charges may apply to any deviations to data and specimen
         retention standards specified herein. Archived data may be maintained
         on microfiche or electronic record, provided that a back-up exists and
         a hard copy can be obtained from it if required.

SECTION XII. MANAGEMENT REPORTING

Quest will provide, upon request from GSK, any or all of the following
management reports generated from Studies under this Agreement: (i) new activity
report, (ii) study status report, (iii) patient visit history report, (iv)
patient trend analysis, (v) trend analysis, (vi) tracking report, (vii) toxicity
grade report, and/or (viii) selected abnormal report, and any other standard
reporting entries as they become available. Quest will make such reports
available as frequently as GSK specifies, and such reports shall be incorporated
into the Result/View(TM) format if requested by GSK. Distribution will be by
standard postal service or electronically, at GSK's option. An additional charge
may apply for customization or deviations to Quest's standard Study management
reports and methods of distribution. Result\View(TM) should be the primary
source for all management reports for all requestors who have access to
Result\View(TM).

SECTION XIII. LABORATORY METHODOLOGY

1.       Quest shall not subcontract tests to any third party or send out
         Referral Specimens without the prior written approval of GSK. Quest
         shall require any subcontractor so approved by GSK to enter into
         written agreements requiring such subcontractor to perform the Services
         for which it is the subcontractor pursuant to the terms of this
         Agreement, including the terms of the confidentiality provisions in
         Section XVIII. Quest shall be responsible for ensuring that (a) all
         subcontracted tests are correctly validated and (b) each
         subcontractor's sites have passed appropriate quality audits conducted
         by third parties hereto within the previous 12 months. If GSK approves
         Quest's use of a subcontractor, GSK shall pay the costs of any testing
         performed by such third party, as charged by the third party to Quest,
         plus Quest's then-current, standard referral fee (currently $25/test in
         the North American Territory and $33/test in the European Territory),
         except as otherwise described in Section XV(1). If GSK requires that
         Quest utilize a particular laboratory for testing and Quest is unable
         to perform its customary site visits and inspection and/or obtain a
         referral agreement with such laboratory (due to small volume of tests,
         short time before Study start, etc.), Quest and GSK shall agree to a
         reasonable solution that addresses the concerns of both Quest and GSK.

2.       On or prior to the date hereof and to the extent available, Quest has
         provided to GSK a current list of all laboratory tests Quest
         Diagnostics Clinical Trials is capable of conducting as updated from
         time to time, (the "Lab Test List") and a


                                       26

<PAGE>

         summary of Quest Diagnostics Clinical Trials laboratory methodology for
         such tests. Quest shall update the Quest Diagnostics Clinical Trials
         Lab Test List and methodology summaries semi-annually or more
         frequently as otherwise necessary if significant changes occur and
         deliver it to GSK. Quest shall also update the Nichols Institute Lab
         Test List and methodology summaries annually or more frequently as
         otherwise necessary if significant changes occur and deliver it to GSK.

3.       From time to time, Quest may determine it necessary to change existing
         methodology and/or reference ranges as a result of modifications in the
         type of reagents and/or methodologies or the discontinuance of
         materials and/or supplies to support existing equipment. To the extent
         practicable, Quest shall notify GSK of any such change not less than
         thirty days before such change is implemented, together with an
         assessment of the potential impact on either validation of assays or
         changes in normal ranges for tests. Quest shall not change any
         methodology and/or reference ranges during the course of a Study
         without the prior written consent of GSK. Upon request from GSK, Quest
         shall provide GSK with any and all method comparison data.

4.       Quest shall investigate any significant trends identified during
         quality control of its laboratory testing that might affect Services
         provided hereunder. Quest shall notify GSK of such trends and provide
         an explanation to GSK regarding these trends.

SECTION XIV. LABORATORY EQUIPMENT

1.       Quest will ensure at all times that its computer equipment is in good,
         working condition and that it has made reasonable provision for backup
         equipment to avoid delays in the analysis of GSK's specimens.

2.       Quest will ensure that any changes in equipment being used in Studies
         that will require revalidation of assays or that may have an impact on
         normal ranges of tests will be communicated to GSK in a timely fashion.
         Quest will make no change in laboratory equipment during the course of
         a Study that would require revalidation of assays, without the prior
         written approval of GSK. Quest shall notify GSK if a failure in its
         equipment causes changes in test results.

3.       Quest shall ensure that the reagents and equipment used in performing
         any Service hereunder, at all times, are in compliance with the reagent
         and equipment standards set forth by applicable regulatory authority's
         standards for such equipment and reagents.


                                       27

<PAGE>

SECTION XV. COMPENSATION

1.       Quest Diagnostics Clinical Trials shall price Services under this
         Agreement (as specified in each Task Description), to GSK, a GSK
         Subsidiary, or GSK's co-promotion, co-development, collaborative or
         similar partners (together with GSK and the GSK Subsidiaries, the "GSK
         Group") at the lower of Most Favored Nations Pricing (as defined in
         subsection (i) below) or the applicable GSK Discount (as defined in
         subsection (ii) below). For the avoidance of doubt, the favorable
         pricing afforded GSK under this Section XV(1) and (2) shall (a) apply
         for any Services requested by the GSK Group in accordance with this
         Agreement and provided by Quest Diagnostics Clinical Trials (including
         without limitation the QDCT Referrals) to the GSK Group under this
         Agreement, whether or not such Services are subject to the exclusivity
         obligations of Section III and (b) not apply to Services performed
         under Alternative Laboratory Agreements. Notwithstanding the foregoing
         and for the avoidance of doubt in interpreting this Section XV with
         respect to the QDCT Referrals, it is understood that Quest Diagnostics
         Clinical Trials prices the QDCT Referrals for its clients as follows:
         testing performed by the Dorevitch and DSP laboratories (and any other
         laboratory with which Quest Diagnostics Clinical Trials establishes a
         similar relationship) is priced at set fees per test, and GSK does not
         receive the GSK Discount on such testing; testing performed by Quest
         laboratories other than Quest Diagnostics Clinical Trials is priced at
         set fees per test, and GSK does receive the GSK Discount on such tests;
         testing performed by all other referral laboratories is priced at
         actual cost plus a referral fee, and GSK does not receive the GSK
         Discount on such tests. In all cases, however, GSK will receive a price
         equal to or lower than that charged to all other Quest Diagnostics
         Clinical Trials clients.

         (i)      "Most Favored Nations Pricing" shall mean the then lowest
                  price for any Service or group of Services being charged by
                  Quest Diagnostics Clinical Trials (including without
                  limitation the QDCT Referrals) to any other client in the
                  North American Territory (with respect to Services to be
                  provided in the North American Territory) or in the European
                  Territory (with respect to Services to be provided in the
                  European Territory). To the extent such other client's(s')
                  prices are in currencies other than US Dollars (for the North
                  American Territory) or Pounds Sterling (for the European
                  Territory), such prices shall be calculated in US Dollars or
                  Pounds Sterling, as applicable, using exchange rates on the
                  date on which Quest Diagnostics Clinical Trials prepared the
                  bid that was submitted to such other client in such other
                  currency.

         (ii)     The "GSK Discount" shall mean the price for any laboratory
                  testing Service calculated using a 32% discount off the then
                  applicable fee schedule for such Service or group of Services
                  being charged by Quest Diagnostics Clinical Trials to any
                  other client in the North American Territory (with respect to
                  Services to be provided in the North American Territory) or
                  20% discount off the then applicable fee schedule for such


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<PAGE>

                  Service or group of Services being charged by Quest
                  Diagnostics Clinical Trials for clients in the European
                  Territory (with respect to Services to be provided in the
                  European Territory).

         (iii)    Any Service or group of Services other than a laboratory
                  testing Service (including without limitation such Service or
                  group of Services performed as a QDCT Referral) shall be
                  provided to the GSK Group at a price equal to or less than the
                  price for such Service or group of Services charged to any
                  other client of Quest Diagnostics Clinical Trials in the North
                  American Territory or in the European Territory, as the case
                  may be.

2.       (i)      For purposes of calculating, pursuant to Section XV(1), prices
                  subject to a GSK Discount, (a) the fee schedule for the most
                  frequently ordered laboratory testing Services performed in
                  2003 shall be as set forth in Exhibit C attached hereto along
                  with the discounted price to be charged to GSK and (b) the
                  prices for laboratory testing Services performed after 2003
                  shall be as agreed to between GSK and Quest pursuant to
                  Section XV(3). All laboratory testing Services requested by
                  the GSK Group at any time for which fees are not specified in
                  the Task Description shall be billed in accordance with Quest
                  Diagnostics Clinical Trials' then current fee schedule,
                  including the applicable discount, unless otherwise agreed to
                  by the parties.

         (ii)     For purposes of calculating the Most Favored Nations Pricing
                  pursuant to Section XV(1) during the Term of this Agreement,
                  Quest shall include all discounts and reductions in price
                  provided by Quest Diagnostics Clinical Trials to its clients
                  in the North American and European Territories excluding any
                  discounts and reductions in price provided by Quest or
                  SmithKline Beecham Clinical Laboratories for Services in
                  connection with Studies that were bid prior to August 16,
                  1999, and have not terminated. Most Favored Nations Pricing
                  shall apply on a test by test basis to invoices for Applicable
                  Studies (as defined in the next sentence) that are submitted
                  to GSK during the time period beginning on the date of the
                  first invoice to another Quest Diagnostics Clinical Trials
                  client containing a discount greater than 32% (in the North
                  American Territory) and 20% (in the European Territory) and
                  ending on the date of the last invoice to such other client
                  containing such greater discount (the "MFN Period"). The term
                  "Applicable Studies" shall mean any GSK Study for which Quest
                  Diagnostics Clinical Trials has prepared a final budget
                  proposal and overview of services during the MFN Period. For
                  example, if Quest Diagnostics Clinical Trials provides a 40%
                  discount to a client for a particular laboratory test in a
                  Study, Quest Diagnostics Clinical Trials must, during the MFN
                  Period, invoice GSK for that test at a 40% discount for all
                  Applicable Studies.

         (iii)    On a quarterly basis, Quest Diagnostics Clinical Trials shall
                  notify GSK if any of the pricing offered to other clients in
                  either the North America or the European Territory is lower
                  than pricing provided to GSK in such


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<PAGE>

                  Territories in accordance with this Section XV. If Quest
                  Diagnostics Clinical Trials has provided more favorable
                  pricing to a client other than GSK in contravention of this
                  Section XV (the "Other Client"), Quest Diagnostics Clinical
                  Trials shall promptly make any necessary credits to GSK's
                  account(s) and ensure that GSK receives the applicable Most
                  Favored Nations Pricing during the MFN Period as provided in
                  this Section XV. GSK shall have the right to audit Quest's
                  records related to pricing provided to other clients of Quest
                  Diagnostics Clinical Trials in accordance with Section XVI for
                  purposes of ensuring Quest's compliance with this Section XV.
                  For Services developed exclusively for the GSK Group or as to
                  which the GSK Group is the sole or predominant customer of
                  Quest Diagnostics Clinical Trials ("Custom Tests"), Most
                  Favored Nations Pricing shall not be greater than Quest
                  Diagnostics Clinical Trials' fully burdened cost to perform
                  such Service plus 20%, subject to the review of the JOC, and
                  in such event the parties shall, prior to commencing any
                  substantive work on creating any Custom Tests, engage in good
                  faith discussions regarding the intellectual property rights
                  to such Custom Tests.

3.       On December 1 of each year, Quest Diagnostics Clinical Trials shall
         submit to GSK's World Wide Medical Director a list of the new clinical
         trials testing prices for the twelve-month period beginning January 1
         of the subsequent year. The total increase in the new clinical trials
         testing prices from the prior year shall not exceed the annual
         inflation rate during the previous twelve month period ending on the
         preceding August 30th, as measured (a) in the North American Territory
         by the change in the overall Consumer Price Index for the United States
         and (b) in the European Territory, by the change in the overall Retail
         Price Index for the United Kingdom. The limitation on price changes set
         forth in this Section XV(3) shall not apply to non-testing charges, or
         to changes in test prices resulting from changes in methodology or
         equipment; provided GSK is notified in writing of such changes and
         approves of them in writing in advance of implementation.

4.       If any Study is revised after such Study's CLW has been approved in
         writing, GSK agrees to pay Quest for Services rendered and actual
         documented costs incurred in the revision of such Study.

5.       If the initiation or conduct of the applicable Study is delayed by
         GSK's direct actions for more than two months such that specimen
         collection/ transport supplies and/or specialized testing reagents
         expire, GSK agrees to pay Quest for Services rendered and actual and
         documented costs incurred to replace expired supplies and/or
         specialized testing reagents. Quest will provide documentation
         reasonably evidencing the replacement of such expired supplies or
         specialized testing reagents.

6.       Quest shall be compensated for supplies properly sent to the
         Investigators which were not used due to patient drop-out or
         cancellation or termination of any Task Description. Quest will provide
         documentation reasonably evidencing the delivery of such supplies.


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<PAGE>

7.       Upon written request from GSK, Quest, for an additional charge per
         language translation, will translate the Investigator Manual into
         languages other than English and Spanish for the U.S. and English,
         Spanish, French, Italian, German and Dutch for the European Territory.

8.       Upon request and with two weeks' prior notification from GSK, Quest
         will provide on-site field service training for protocol initiation
         and/or ongoing support. Costs associated with this service (additional
         reasonable charge per day plus travel and accommodation expenses) shall
         be borne by GSK.

9.       GSK is responsible for the cost of travel and accommodation for Quest's
         representatives at Investigator meetings to the extent GSK has approved
         their attendance, provided that expenses are incurred in accordance
         with GSK's travel policy, a copy of which has been provided to Quest.

10.      Quest will make available, upon GSK's request, professional laboratory
         consulting services at GSK and/or Investigator sites. Any costs
         associated with these services shall be agreed to in advance by Quest
         and GSK.

11.      Inbound transportation will be charged from the Investigator site to
         Quest laboratories for actual commercial carrier costs (exclusive of
         any periodic or volume rebates but inclusive of discounts) plus a 10%
         administrative fee. Outbound transportation of starter kits,
         resupplies, dry ice and reports from Quest laboratories to the
         Investigator sites will be charged at actual commercial carrier costs
         plus a 10% administrative fee. Actual charges for transportation costs
         will be reviewed annually, beginning at March 30, 2003.

12.      In the event that the actual costs to Quest of courier services for (i)
         specimen transport, (ii) supply shipment, or (iii) result reporting,
         changes at any time during the term of a Study, whether because of a
         change in the fees charged by Quest's proprietary or commercial
         courier, a change in the cost of packaging materials used to ship
         specimens, or a mandatory change in applicable regulations, Quest shall
         have the right to change the courier fees quoted herein to the same
         extent as the actual change in the invoiced cost of courier services.

13.      Quest shall be compensated at actual cost plus 10% for emergency
         delivery and/or transportation Services authorized by GSK which are not
         included in fees noted in the relevant Task Description.

14.      If, at any time, GSK chooses to change the level of service provided by
         the courier and that change is accompanied by an increase in the fee to
         Quest, Quest reserves the right to pass that increase on to GSK;
         provided, however, that Quest shall make no change that decreases the
         level of courier service provided without the consent of GSK.

15.      Quest will charge GSK an annual fee for each Archival Specimen stored
         on behalf of GSK. The fees for North American Territory and European
         storage are as stated in the Applicable Task Description. Quest
         Diagnostics Clinical Trials


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<PAGE>

         will inform GSK in writing by December 1 of each year of the fees for
         such storage the proposed fees to be in effect for the subsequent year
         beginning January 1, if different than the then-existing prices, and
         Quest and GSK will negotiate in good faith to agree on such fees as
         promptly as practicable after such notification.

16.      Quest shall promptly invoice GSK for all testing Services provided
         hereunder on a monthly basis. All invoices submitted by Quest to GSK
         shall identify the Services rendered by Study, Investigator's name,
         patient designation, tests and testing date. All payments due Quest for
         Services provided shall be made to Quest within 30 days of GSK's
         receipt of an invoice including the above information for Services
         provided in the North American Territory and within 45 days of GSK's
         receipt of an invoice including the above information for Services
         provided in the European Territory. GSK shall not be required to make
         payment to Quest on any invoice unless the invoice contains all
         information specified herein.

SECTION XVI. AUDITS, INSURANCE AND PERSONNEL CHANGES

1.       Financial Audits. During the Term of this Agreement, and until two
         years after its expiration or termination, GSK may direct the audit of
         any financial records of Quest relating to Services provided under this
         Agreement, or any Addenda hereunder. Such records may include invoice
         records, invoices from third parties, contracts with third parties and
         payments relating to any Studies hereunder. To the extent that such
         records are not separable from other customer records or GSK is
         auditing compliance with the compensation terms of Section XV, Quest
         shall give reasonable access to Quest's records to such independent
         auditor selected by GSK and reasonably agreeable to Quest, who shall
         audit the records pertaining to the Addenda, and may disclose the
         results of the audit only to the extent that it relates to any Study
         hereunder, or to this Agreement. In no event shall other customer
         information be disclosed to GSK except on a blind basis with respect to
         pricing.

2.       Quality Audits. GSK, at reasonable times and upon reasonable advance
         notice, may, at its sole cost and expense, visit Quest Diagnostics
         Clinical Trials' and any QDCT Referral Laboratory's testing facilities
         to conduct quality assurance audits of Quest Diagnostics Clinical
         Trials' and the QDCT Referral Laboratory's facilities and the
         procedures implemented for any Study. At its option, GSK may elect to
         use a third party to conduct such audit. GSK or its agent must sign
         Quest Diagnostics Clinical Trials' or the QDCT Referral's (as
         applicable) standard Confidentiality Agreement at the time of its visit
         to Quest Diagnostics Clinical Trials' or the QDCT Referral Laboratory's
         testing facilities. Quest Diagnostics Clinical Trials and the QDCT
         Referral Laboratories will maintain adequate records so as to allow GSK
         or its agent to conduct and audit testing Services relative to Studies
         as well as Quest Diagnostics Clinical Trials' tracking and measurement
         of performance metrics for each Study. Quest Diagnostics Clinical


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<PAGE>

         Trials and the QDCT Referral Laboratory also shall maintain records
         demonstrating the training and qualifications of their respective
         employees. GSK shall advise Quest Diagnostics Clinical Trials and the
         QDCT Referral Laboratory in writing of any special or unusual record
         keeping needs for any Study, and Quest Diagnostics Clinical Trials and
         the QDCT Referral Laboratory will use their reasonable best efforts to
         accommodate GSK's requirements. Additional charges will apply for any
         requirements in excess of Quest Diagnostics Clinical Trials' and the
         QDCT Referral Laboratory's usual record keeping process; provided,
         however, that Quest Diagnostics Clinical Trials must itemize such
         charges for GSK in reasonable detail. Quest Diagnostics Clinical Trials
         agrees to maintain such records in confidence in accordance with
         applicable laws, rules and regulations. GSK shall notify Quest
         Diagnostics Clinical Trials of any serious quality deficiencies
         identified in any GSK audit or GSK sponsored audit, and Quest
         Diagnostics Clinical Trials or the QDCT Referral Laboratory, as the
         case may be, shall have three months from the date of such notification
         to remedy such deficiencies. With respect to deficiencies identified at
         a QDCT Referral Laboratory, if the QDCT Referral Laboratory has not
         remedied such deficiencies within such three-month period, GSK may
         require that the affected Services being performed by the QDCT Referral
         Laboratory be performed by another QDCT Referral Laboratory or that GSK
         and Quest Diagnostics Clinical Trials work together expeditiously to
         identify an alternative referral laboratory satisfactory to GSK at
         which such Services shall be performed. With respect to deficiencies
         identified at Quest Diagnostics Clinical Trials, if Quest Diagnostics
         Clinical Trials does not remedy such deficiencies within such
         three-month period, GSK shall (a) refer the matter to the JOC for
         resolution under Sections IV(3) and IV(6) or (b) engage a reputable and
         experienced third party to audit Quest Diagnostics Clinical Trials with
         respect to such deficiencies. If the matter remains unresolved after
         consideration by the JOC and the parties' executives under Section
         IV(6) or if the second audit confirms the results of GSK's or its
         agent's initial audit, Quest Diagnostics Clinical Trials' failure to
         remedy such deficiencies shall be deemed to constitute a Material
         Breach under this Agreement for purposes of Section XXI. Quest
         Diagnostics Clinical Trials and the QDCT Referral Laboratories shall
         afford GSK at least equal priority with their other preferred customers
         in maintaining the continuity and quality of performance of Services,
         and shall make diligent and timely efforts to comply with each of their
         respective obligations in this Section XVI.

3.       Exclusivity Audits. Quest, at reasonable times and upon reasonable
         advance notice, may, at its sole cost and expense, direct the audit of
         relevant GSK records to determine if testing is being performed by
         parties other than Quest in violation of Section III of this Agreement.
         Such records may include invoice records, invoices from third parties,
         contracts with third parties and payments relating to any Studies
         conducted by GSK. To the extent that such records are not separable
         from other records of GSK, GSK shall give reasonable access to GSK's
         records to such independent auditor selected by Quest and reasonably
         agreeable to GSK, who shall audit the records pertaining to the
         exclusivity requirement under Section III, and may disclose the results
         of the audit only to


                                       33

<PAGE>

         the extent that it relates to compliance with Section III of this
         Agreement. In no event shall other information regarding Studies be
         disclosed to Quest except on a blind basis with respect to the
         exclusivity requirement under Section III. At its option, Quest may
         elect to use a third party to conduct such audit. Quest or its agent
         must sign GSK's standard Confidentiality Agreement prior to the time
         GSK makes its records available. Quest shall notify GSK of any breaches
         of Section III of this Agreement identified in any Quest audit or Quest
         sponsored audit.

4.       Other. Quest shall provide GSK with copies of (a) any audits (other
         than financial or tax audits) conducted by any regulatory authority,
         which audit uncovers deficiencies in the quality of Services provided
         by Quest Diagnostics Clinical Trials to GSK or a GSK Subsidiary, and
         (b) any written communication by any regulatory authority alleging a
         failure to comply with any applicable law or regulation, including any
         483 notices received by Quest Diagnostics Clinical Trials or a QDCT
         Referral from the United States Food and Drug Administration.

5.       Insurance. Quest agrees to keep and maintain in full force and effect
         professional liability and/or comprehensive liability insurance or self
         insurance that covers liability arising in connection with the Services
         performed under this Agreement with minimum coverage of $2,000,000 for
         each occurrence or claim and $30,000,000 in the aggregate annually.
         Upon the signing of this Agreement and annually thereafter, Quest
         agrees to furnish GSK with a current and valid certificate of insurance
         or self-insurance evidencing the extent of professional and/or
         comprehensive liability coverage.

6.       Personnel. To ensure the continuing quality of its Services, Quest
         shall notify GSK of any changes in key personnel of Quest Diagnostics
         Clinical Trials, including any change in the Quest Director or the
         liaisons to GSK facilities. In addition, Quest shall immediately notify
         GSK of any change in the Project Leader for a Study.

SECTION XVII. SERVICE MINIMUMS AND INCENTIVES

1.       Annual Minimum Spend.

         (i)      In the event the revenues earned by Quest for Services
                  rendered under this Agreement by Quest from January 1, 2002
                  through December 31, 2002 ("2002 Revenues") are less than
                  $31,800,000, GSK will pay Quest on or before February 28,
                  2003, the amount of $31,800,000 minus 2002 Revenues.

         (ii)     In the event the revenues earned by Quest for Services
                  rendered under this Agreement by Quest from January 1, 2003
                  through December 31, 2003 ("2003 Revenues") are less than
                  $31,800,000, GSK will pay Quest on or before February 28,
                  2004, an amount equal to $31,800,000 minus the 2003 Revenues.


                                       34

<PAGE>

         (iii)    The parties understand and agree that due to the nature of
                  invoicing and payment cycles, it is possible that the 2003
                  Revenues may be over- or under-stated by a small amount. If
                  after formal closing of the annual financial records of the
                  parties it is agreed by the parties that GSK overpaid or
                  underpaid under Section XVII(1)(ii) above, the parties will
                  make any required reconciliation of the financial accounts
                  promptly, and any difference will be either paid to Quest by
                  GSK or credited to GSK by Quest no later than March 31, 2004.

         (iv)     The AMS Targets shall be as follows:

                                   AMS TARGET

<TABLE>
<CAPTION>
Year           2003      2004      2005      2006      2007      2008      2009
----          ------   -------   -------   -------   -------   -------   -------
<S>           <C>      <C>       <C>       <C>       <C>       <C>       <C>
Millions      $34.98   $38.478   $42.326   $46.559   $51.215   $56.337   $61.950
</TABLE>

2.       Minimum Total Contract Value. The minimum total contract value for
         revenue earned by Quest for Services rendered under this Agreement
         ("TCV") from January 1, 2004 through December 31, 2009 shall be
         $276,700,000, net of any portion of the Credit actually used by GSK
         with respect to such period as provided in Section XVII(5). If the
         aggregate revenue earned by Quest for Services rendered under this
         Agreement from January 1, 2002 through December 31, 2003 exceeds
         $66,800,000 (net of any portion of the Credit actually used by GSK with
         respect to such period), the TCV shall be reduced by the difference
         between the actual revenue earned by Quest for Services rendered under
         this Agreement from January 1, 2002 through December 31, 2003 and
         $66,800,000. In the event the actual revenue earned by Quest for
         Services rendered under this Agreement for the period from January 1,
         2004 through December 31, 2009 ("Six Year Period Revenue") is less than
         the TCV, GSK shall pay an amount equal to the TCV (as adjusted) less
         the Six Year Period Revenue on or before February 28, 2010, unless
         otherwise mutually agreed in writing by the parties.

3.       AMS Target Incentives. If GSK exceeds the AMS Target for any individual
         calendar year (net of any portion of the Credit actually used with
         respect to such Period), GSK shall be entitled to a discount calculated
         by using the following formula:


                                       35

<PAGE>


YEARS 2003 - 2005

<TABLE>
<CAPTION>
                 Annual Revenue                                    Range of
                   Above AMS           Additional Discount   Additional Discount
                      US$               % Applied to Tier      $ Earned on Tier
             ----------------------    -------------------   -------------------
<S>          <C>                               <C>               <C>
Tier 1            1 -- 7,500,000                 5%               0 -- 375,000
Tier 2       7,500,001 -- 15,000,000            10%               0 -- 750,000
Tier 3        15,000,001 and above             15%
</TABLE>

YEARS 2006 - 2009

<TABLE>
<CAPTION>
                 Annual Revenue                                    Range of
                   Above AMS           Additional Discount   Additional Discount
                      US$               % Applied to Tier      $ Earned on Tier
             ----------------------    -------------------   -------------------
<S>          <C>                             <C>                 <C>
Tier 1            1 -- 5,000,000              2 1/2%              0 -- 125,000
Tier 2       5,000,001 -- 10,000,000              5%              0 -- 250,000
Tier 3        10,000,001 and above               10%
</TABLE>


         For example and for illustrative purposes only, if in year 2004 annual
         revenue were $17 million above the AMS Target, the discount would be
         $1,425,000 ($375,000 + $750,000 + $300,000). Any additional discounts
         earned by GSK in any individual calendar year, as described in the
         tables above, may, at GSK's discretion, be either applied to subsequent
         invoices for the remainder of that calendar year or paid by Quest to
         GSK on or before February 28 of the subsequent calendar year.

4.       It is expressly agreed by the parties that the AMS Targets are solely
         for the purpose of calculating entitlement to or use of credits and/or
         additional discounts, and in no way create an obligation to generate an
         annual minimum amount of revenue for Quest after 2003. In addition, for
         the avoidance of doubt, for purposes of calculating under this
         Agreement the amount of the revenues earned by Quest for Services
         rendered under this Agreement, all Services requested by GSK in
         accordance with this Agreement (including without limitation Section
         II(1)) and provided under this Agreement or under Alternative
         Laboratory Agreements to the GSK Group shall be included, whether or
         not such Services are subject to the exclusivity obligations of Section
         III.

5.       Subject to the further conditions of this Section XVII(5), in 2003 GSK
         shall receive a credit for $4,200,000 of Services at no charge from
         Quest (the "Credit"). The Credit shall be applied only after
         satisfaction of the AMS Target in any given year, beginning in 2003,
         and only to a maximum of $2,000,000 in any year. (By way of example, in
         2003 GSK will first be required to reach the 2003 AMS Target of
         $34,980,000 before the Credit will be applied. The Credit will then be
         applied dollar for dollar to the next $2,000,000 of revenue earned by
         Quest in


                                       36

<PAGE>

         excess of $34,980,000 during such year. The balance of the Credit shall
         carry forward from year to year under this Agreement until exhausted or
         until the Agreement expires or is terminated. The Credit shall not be
         counted toward achieving the TCV, any AMS Target Incentives set forth
         in Section XVII(3) above, or the incentive described in Section XVII(6)
         below. The Credit (or any balance thereof) shall not survive past the
         termination of this Agreement, and any unused portion of the Credit
         shall expire on December 31, 2009.

6.       Extension Agreement. As a mutual incentive to encourage the extension
         of this Agreement for three years after its termination on December 31,
         2009, GSK shall be entitled to utilize a "renewal" credit in each of
         2010, 2011, and 2012 equal to one-third of the amount of the aggregate
         discount GSK earns in the period from January 1, 2003 through December
         31, 2009 under the provisions of Section XVII(3) above. Such credit
         shall be available to GSK if and only if the following conditions are
         satisfied:

         (i)      GSK and Quest agree to extend this Agreement for an additional
                  three-year period; and

         (ii)     the aggregate revenue earned by Quest for Services rendered
                  under this Agreement from January 1, 2004 through December 31,
                  2009 under this Agreement (net of any portion of the Credit
                  actually used by GSK during such period) exceeds the TCV of
                  $276,700,000 (as adjusted).

         Utilization of the renewal credit in any year is subject to a maximum
         of 2% (two percent) of the aggregate revenue earned by Quest for
         Services rendered under this Agreement in that same calendar year. The
         unused credit balance at the end of the extension shall expire.

SECTION XVIII. CONFIDENTIALITY AND OWNERSHIP OF SPECIMENS AND DATA

1.       During the performance of this Agreement, GSK may provide to Quest or
         Quest may generate data, test results, Studies, and other information
         regarding the drug under Study, or regarding the protocols or other
         information relating to research programs being conducted by GSK or the
         business of GSK. Quest understands that GSK considers such information
         to be confidential. Quest will not use such confidential information
         except for the purpose of conducting the Study for GSK and will
         maintain the information in confidence to the extent that it is not
         already known to the public and for such time as it remains unknown to
         the public. Quest may disclose such information to only those
         employees, agents, contractors and consultants who are reasonably
         necessary to carry out the terms of this Agreement and shall take
         reasonable measures to ensure that such employees, agents, contractors
         and consultants maintain the confidentiality of this information. Quest
         may disclose such confidential information to any QDCT Referral
         Laboratory for purposes of providing Services to GSK. Quest shall


                                       37

<PAGE>

         ensure that any QDCT Referral Laboratory to whom Quest refers testing
         shall be obligated in writing to maintain the confidentiality of such
         confidential information (whether received from Quest or GSK or
         generated by such laboratory in connection with its testing for GSK) to
         the same extent as Quest hereunder. For the avoidance of doubt, this
         provision is not intended to supersede the confidentiality provisions
         of any Alternative Laboratory Agreements.

2.       During the performance of this Agreement, Quest may provide to GSK
         information regarding Quest's standard operating procedures, processes,
         testing procedures, pricing and other information relating to the
         clinical trials testing business conducted by Quest. GSK understands
         that Quest considers such information to be confidential. GSK will not
         use such confidential information except for the purpose of conducting
         its Study and will maintain the information in confidence to the extent
         it is not already known to the public and such information remains
         unknown to the public. GSK may disclose such confidential information
         to only those employees, agents, contractors and consultants who are
         reasonably necessary to carry out the terms of this Agreement and shall
         take reasonable measures to ensure that such employees, agents,
         contractors and consultants maintain the confidentiality of this
         information.

3.       To the extent confidential information is already known to the public
         or becomes known to the public from any source other than the party
         bound hereunder by this obligation of confidentiality, there shall be
         no obligation of confidentiality. The obligation of confidentiality as
         set forth in this paragraph shall survive for ten years following the
         termination of this Agreement. Upon termination of this Agreement, all
         documents containing confidential information shall be returned to the
         party who disclosed the confidential information within sixty days of a
         written request. If either party is required by law or valid court
         order to disclose confidential information of the other party, it shall
         promptly notify the other party of the disclosure requirement.

4.       All right, title, and interest in and to any specimens obtained by GSK
         during the course of any Study and any data generated from any Study,
         whether by GSK or its Affiliates, an Investigator, subcontractor or
         other Person or by Quest in the course of providing Services pursuant
         to this Agreement are the proprietary rights of GSK and its Affiliates,
         and all ownership rights in such specimens and data shall remain with
         GSK and its Affiliates. Nothing herein or in any Task Description shall
         grant or be deemed to grant to Quest any rights in such property of GSK
         or its Affiliates. Quest acknowledges and agrees that it shall have no
         claim to any specimens or data obtained by GSK or its Affiliates or
         generated on its behalf by Quest or any Investigator, subcontractor,
         agent or Person during the course of any Study. Upon request of GSK,
         Quest shall return all specimens and data to GSK; provided, however,
         that Quest may retain copies of any data necessary to satisfy
         applicable regulatory requirements.

5.       Data Privacy Laws. Each party shall be responsible for ensuring that
         the performance of its obligations under this Agreement complies with
         any applicable


                                       38

<PAGE>

         provisions of the Health Insurance Portability and Accountability Act
         and its implementing regulations, as amended from time to time
         ("HIPAA"). In the event that this Agreement or any practices which are
         employed in performance of this Agreement do not satisfy either party's
         obligations under HIPAA, the parties shall agree in good faith upon an
         appropriate amendment to this Agreement and to execute and deliver any
         documents required to comply with HIPAA.

SECTION XIX. CANCELLATION

In the event that a Study is canceled by GSK after Quest has been authorized to
render start-up Services, including (a) the purchase of specialized testing
reagents and/or supplies, (b) preparation and/or distribution of specimen
collection/transport supplies, or (c) protocol administration and/or data
management Services, Quest, at its sole option, may charge GSK, and GSK agrees
to reimburse Quest, for actual Services rendered and actual costs incurred in
the set-up of the Study in each case, upon receipt by GSK of reasonable
documentation evidencing such Services and such costs.

SECTION XX. TERM AND OBLIGATIONS SURVIVING TERMINATION

1.       The Term of this Agreement shall commence on the date hereof and shall
         end on the earlier to occur of (a) December 31, 2009 and (b) the date
         this Agreement is otherwise terminated pursuant to its terms; provided,
         however, that the parties by mutual written agreement may extend this
         Agreement through December 31, 2012 or any other mutually agreed
         period.

2.       If this Agreement is terminated, this Agreement shall become void and
         of no further force or effect, except that (a) the obligations set
         forth in this Agreement (including in the Addenda) with respect to any
         Study which has not been completed at the time of such termination and
         (b) the obligations set forth in Sections XV, XVI, XVIII, XX, XXII and
         XXV shall, in each case, survive such termination, unless otherwise
         separately terminated or canceled in writing by GSK and Quest;
         provided, however, that in the event that this Agreement is terminated
         by GSK as a result of a Material Breach, GSK may elect, in its sole
         discretion, also to terminate any Study which has not been completed at
         the time of such termination with no further obligation to Quest except
         for liabilities accrued but unpaid at the time of such termination.

SECTION XXI. BREACH

1.       A "MATERIAL BREACH" by Quest of this Agreement means any of the
         following:

         (i)      Any failure to provide Services with respect to any Study
                  pursuant to the terms of this Agreement which failure results
                  in (or, if after GSK becomes aware of such failure, without
                  the use of substantial resources of GSK not


                                       39

<PAGE>

                  initially planned or budgeted and not reimbursed by Quest
                  would have caused) a substantial delay, which delay is caused
                  solely by the failure of Quest to provide Services under this
                  Agreement, in any of

                  (a)      the initiation or completion of the conduct of a
                           Study that GSK or a GSK Subsidiary identifies as
                           Pivotal; provided, however, that GSK shall advise
                           Quest at the quarterly JOC meetings of which Studies
                           it deems to be Pivotal;

                  (b)      the completion of the reporting of the laboratory
                           results of such Study or of a clinical Study report
                           or other regulatory submission for such Study;

                  (c)      the acceptance by the relevant regulatory authority
                           of the results of such Study, clinical Study report
                           or regulatory submission for such Study; or

                  (d)      the completion of the regulatory review process
                           (e.g., such failure results in additional for-cause
                           audits or regulatory questions related to laboratory
                           issues);

         (ii)     Any failure to satisfy, in any material respect, the U.S.
                  Clinical Laboratory Improvements Amendments (CLIA 88), or good
                  clinical laboratory practices or generally accepted industry
                  standards for quality assurance and quality control, including
                  the standards set forth in the United States Federal Food,
                  Drug and Cosmetics Act or promulgated by the College of
                  American Pathologists, or any failure by Quest promptly to
                  remedy any deficiencies uncovered in any audit by the FDA or
                  equivalent European regulatory authority where any of the
                  foregoing failures in this sub-section XXI(1)(ii) jeopardizes
                  Quest's ability to perform Services under this Agreement;

         (iii)    Repeated and continued material failure to provide Services
                  pursuant to the terms of this Agreement which failures have
                  been raised pursuant to Section IV of this Agreement and
                  resolution thereof attempted under Section IV(6), and which
                  remain unresolved, including, without limitation:

                  (a)      repeated and continued failures to satisfy in any
                           material respect the requirements of this Agreement
                           with respect to data management and reporting of test
                           results;

                  (b)      repeated and continued failure to satisfy the
                           standards or requirements for Study preparation,
                           management or conduct in this Agreement (e.g., the
                           timely and accurate provision of supplies and
                           materials and maintaining the Study Blind);

                  (c)      the failure, with respect to 5% of Studies within any
                           12 month period, to provide 90% of the testing sites
                           for any such Studies with


                                       40

<PAGE>

                           the supplies required for such Study in the
                           implementation time specified in this Agreement for
                           such Studies;

                  (d)      any error in, or repeated and continued failure in
                           quality of, Services provided by Quest under this
                           Agreement which causes Investigators for any Study to
                           withdraw their participation in any Study;

         (iv)     Any Material Breach that occurs pursuant to Section XVI(2)
                  provided that the issue(s) causing the alleged Material Breach
                  have been raised pursuant to Section IV of this Agreement and
                  resolution thereof attempted under Section IV(6), and such
                  issues remain unresolved; and

         (v)      Any other material breach by Quest of the terms of this
                  Agreement which breach has been raised pursuant to Section IV
                  of this Agreement and resolution thereof attempted under
                  Section IV(6), and which remains unresolved.

2.       A "MATERIAL BREACH" by GSK means any material breach by GSK of the
         terms of this Agreement which breach has been raised pursuant to
         Section IV of this Agreement and resolution thereof attempted under the
         provisions of Section IV(6), and which remains unresolved.

3.       Remedies for Breach.

         (i)      Remedies. In the event of an unresolved Material Breach under
                  Sections XXI(1)(ii) through XXI(v), and provided Quest has
                  failed to cure the breach (if curable) within the cure period
                  set forth below in Section XXI(4), or in the event of a
                  Material Breach by Quest pursuant to Section XXI(1)(i), GSK
                  may:

                  (a)      Terminate this Agreement immediately; or

         (ii)     In its sole discretion, terminate only its obligation in
                  Section III to exclusively use Quest without terminating the
                  entire Agreement. For the avoidance of doubt, in connection
                  with termination of exclusivity under this Section
                  XXI(3)(i)(b), GSK shall retain the right to favorable pricing
                  under Section XV and the obligation to meet all Spend Targets.

         (iii)    Additional Remedies for Material Breach. If there is any
                  uncured Material Breach by either party under this Agreement,
                  the non-breaching party shall be entitled to any and all
                  remedies available at law and equity or under this Agreement,
                  including, without limitation, injunctive relief against the
                  breaching party to require it to comply with its obligations
                  under this Agreement.

4.       Cure Periods Related to Breach. For any Material Breach by GSK and any
         Material Breach or Repeated and Continuous Failure (as defined in
         Section


                                       41

<PAGE>

         XXI(5) below) by Quest pursuant to Sections XXI(1)(ii) through (v) or
         XXI(5) hereof, the non-breaching party shall provide notice to the
         breaching party of the Material Breach or Repeated and Continuous
         Failure, with 30 days to cure such breach. If the Material Breach or
         Repeated and Continuous Failure is cured during the 30 day period (or
         if not curable within a 30 day period, the breaching party has
         commenced the cure and continues to diligently work, meeting mutually
         agreed to milestones, to cure the breach), the notice of breach will be
         deemed withdrawn. For the avoidance of doubt: (a) before the
         non-breaching party may provide the notice of breach under this Section
         XXI(4), the non-breaching party shall have attempted to resolve the
         issues underlying the alleged Material Breach or Repeated and
         Continuous Failure through the structure set out in Section IV(6); and
         (b) the cure periods provided in this Section XXI(4) shall be in
         addition to and separate from the time established for the parties to
         attempt to resolve the alleged Material Breach(es) or Repeated and
         Continuous Failure(s) pursuant to Section IV above or XXI(5) below. Any
         Material Breach by Quest pursuant to Section XXI(1)(i) shall not be
         subject to the cure period specified herein and, upon the occurrence of
         such Material Breach, GSK may immediately exercise its rights as
         provided in Section XXI(3) above.

5.       Repeated and Continuous Failure by Quest. If Quest has repeatedly and
         continually failed to provide Services hereunder in accordance with the
         generally-accepted quality standards in the clinical trials central
         laboratory testing industry, which failures do not rise to the level of
         a Material Breach under Section XXI(1) (a "Repeated and Continuous
         Failure"), GSK shall escalate its concerns to the JOC under Section
         IV(6) of this Agreement. After completion of the process described in
         Section IV(6), GSK may send Quest a notice under Section XXI(4) above;
         if GSK does not send such notice within 180 days after completion of
         such process, GSK shall be deemed to have waived that Repeated and
         Continuous Failure (provided that any such waiver shall not operate as
         a waiver of future, similar Repeated and Continuous Failures).

6.       Excluded Breaches. For the avoidance of doubt, breaches by parties
         performing Services for GSK under Alternative Laboratory Agreements
         shall not be grounds for Material Breaches or Repeated and Continuous
         Failures by Quest under this Agreement.

SECTION XXII. INDEMNIFICATION

1.       Indemnification by Quest. Quest agrees to defend, indemnify and hold
         harmless GSK, its Affiliates, and their respective officers, directors,
         employees, stockholders, agents and representatives from claims,
         demands, costs, expenses (including reasonable attorney's fees) and
         liabilities or losses (collectively, "Losses") which may be asserted
         against or incurred by GSK, its Affiliates, and their respective
         officers, directors, employees, stockholders, agents and
         representatives, caused or alleged to be caused by Quest, or its
         respective Affiliates, officers, directors, employees, agents or
         representatives in


                                       42

<PAGE>

         providing Services under the terms of the Agreement; provided, however,
         that Quest shall have no liability under this Section XXII(1) to the
         extent such Loss arises solely as a result of any negligent, improper
         or illegal act or failure to act on the part of GSK, its Affiliates or
         their respective officers, directors, employees, stockholders, agents,
         or representatives.

2.       Indemnification by GSK. GSK agrees to defend, indemnify and hold
         harmless Quest, its respective Affiliates, officers, directors,
         employees, stockholders, agents and representatives from any and all
         Losses which may be asserted against Quest, its respective Affiliates,
         officers, directors, employees, stockholders, agents and
         representatives which result from or arise out of (a) the manufacture,
         distribution, sale or use in any manner of the pharmaceutical compound
         being tested by Quest, or (b) the conduct of clinical trials by GSK,
         its Affiliates, or their respective officers, directors, employees,
         agents or representatives; provided, however, that GSK shall not have
         any liability under this Section XXII(2) to the extent such Loss arises
         solely as a result of any negligent, improper or illegal act or failure
         to act on the part of Quest, or its respective Affiliates, officers,
         directors, employees, stockholders, agents, or representatives.

3.       Limitations on Quest's Liability. Notwithstanding Section XXII(1), the
         liability of Quest under this Agreement shall be no greater than:

         (i)      in the case where Quest's breach has not rendered a Study
                  invalid, a reduction in the total contract price for the Study
                  in an amount equal to the difference between (a) the total
                  contract price for the Study and (b) the value of the work
                  properly performed; and

         (ii)     in the case where Quest's breach renders a Study invalid, a
                  refund of the total contract price paid by GSK or an GSK
                  Subsidiary to Quest, plus the difference in such contract
                  price and any additional, commercially reasonable amounts that
                  GSK or an GSK Subsidiary must incur to have the Study
                  performed over; provided, however, that any Study that GSK
                  shall have performed over shall be performed using similar
                  standards that were required by GSK or an GSK Subsidiary of
                  Quest initially for the Study. In such a situation where
                  Quest's breach renders a Study invalid, GSK or the GSK
                  Subsidiary shall have the option to have Quest re-perform the
                  Study at no additional expense to GSK or the GSK Subsidiary
                  or, alternatively, to have a clinical laboratory other than
                  Quest perform the Study. If GSK or the GSK Subsidiary elects
                  to have another laboratory perform the Study, GSK and the GSK
                  Subsidiary shall be released from the obligations under
                  Section III to use Quest on an exclusive basis, but only for
                  the particular Study that was invalidated by Quest's breach.

         UNDER NO CIRCUMSTANCES SHALL GSK BE ENTITLED TO, NOR SHALL QUEST BE
         RESPONSIBLE FOR, ANY INCIDENTAL, INDIRECT, CONSEQUENTIAL OR SPECIAL
         DAMAGES (INCLUDING, WITHOUT


                                       43

<PAGE>

         LIMITATION, LOST PROFITS) ARISING AS A RESULT OF OR IN CONNECTION WITH
         QUEST'S DEFAULT OR BREACH OF ITS OBLIGATIONS UNDER THIS AGREEMENT OR
         ANY GIVEN STUDY, OR ANY DOCUMENTS RELATED THERETO.

4.       Limitations on GSK's Liability.

         (i)      If GSK terminates this Agreement as a result of a Repeated and
                  Continuous Failure, the liability of GSK under this Agreement,
                  including, without limitation, liability for lost profits and
                  interest of Quest, shall not exceed the greater of:

                  (a)      Twenty percent of the number equal to [$340,300,000
                           minus the revenue earned by and paid to Quest for
                           Services rendered under this Agreement and the
                           Alternative Laboratory Agreements after January 1,
                           2002]; or

                  (b)      $30,000,000.

                  For the avoidance of doubt, the limitations on GSK's liability
                  to Quest as provided for in this Section XXII(4)(i) shall
                  apply if, and only if, Quest has committed a Repeated and
                  Continuous Failure and GSK subsequently terminates this
                  Agreement; otherwise, the limitations provided for in this
                  Section XXII(4)(i) shall not apply.

         (ii)     UNDER NO CIRCUMSTANCES SHALL QUEST BE ENTITLED TO, NOR SHALL
                  GSK BE RESPONSIBLE FOR, ANY INCIDENTAL, INDIRECT,
                  CONSEQUENTIAL OR SPECIAL DAMAGES, OTHER THAN LOST PROFITS AND
                  INTEREST THEREON, ARISING AS A RESULT OF OR IN CONNECTION WITH
                  GSK'S TERMINATION OF THIS AGREEMENT OR DEFAULT OR BREACH OF
                  ITS OBLIGATIONS UNDER THIS AGREEMENT OR ANY GIVEN STUDY, OR
                  ANY DOCUMENTS RELATED THERETO.

         (iii)    Notwithstanding anything in this Section XXII(4) to the
                  contrary, this Section XXII(4) shall have no effect on Section
                  XXII(2).

5.       Procedures Relating to Indemnification of Third Party Claims. In order
         for a party (the "indemnified party") to be entitled to any
         indemnification provided for under this Agreement in respect of,
         arising out of or involving a claim or demand made by any Person
         against the indemnified party (a "Third Party Claim"), such indemnified
         party must notify the indemnifying party in writing, and in reasonable
         detail, of the Third Party Claim within 15 business days after receipt
         by such indemnified party of written notice of the Third Party Claim;
         provided, however, that failure to give such notification shall not
         affect the indemnification provided hereunder except to the extent the
         indemnifying party shall have been actually prejudiced as a result of
         such failure (except that the indemnifying party shall not be liable
         for any expenses incurred during the period in which the indemnified


                                       44

<PAGE>

         party failed to give such notice). Thereafter, the indemnified party
         shall deliver to the indemnifying party, within five business days
         after the indemnified party's receipt thereof, copies of all notices
         and documents (including court papers) received by the indemnified
         party relating to the Third Party Claim.

         If a Third Party Claim is made against an indemnified party, the
         indemnifying party shall be entitled to participate in the defense
         thereof and, if it so chooses and acknowledges its obligation to
         indemnify the indemnified party therefor, to assume the defense thereof
         with counsel selected by the indemnifying party; provided that such
         counsel is not reasonably objected to by the indemnified party. Should
         the indemnifying party so elect to assume the defense of a Third Party
         Claim, the indemnifying party shall not be liable to the indemnified
         party for legal expenses subsequently incurred by the indemnified party
         in connection with the defense thereof. If the indemnifying party
         assumes such defense, the indemnified party shall have the right to
         participate in the defense thereof and to employ counsel, at its own
         expense, separate from the counsel employed by the indemnifying party,
         it being understood that the indemnifying party shall control such
         defense. The indemnifying party shall be liable for the fees and
         expenses of counsel employed by the indemnified party for any period
         during which the indemnifying party has failed to assume the defense
         thereof (other than during the period prior to the time the indemnified
         party shall have given notice of the Third Party Claim as provided
         above).

         If the indemnifying party so elects to assume the defense of any Third
         Party Claim, all of the indemnified parties shall cooperate with the
         indemnifying party in the defense or prosecution thereof. Such
         cooperation shall include the retention and (upon the indemnifying
         party's request) the provision to the indemnifying party of records and
         information which are reasonably relevant to such Third Party Claim,
         and making employees available on a mutually convenient basis to
         provide additional information and explanation of any material provided
         hereunder. Whether or not the indemnifying party shall have assumed the
         defense of a Third Party Claim, the indemnified party shall not admit
         any liability with respect to, or settle, compromise or discharge, such
         Third Party Claim without the indemnifying party's prior written
         consent (which consent shall not be unreasonably withheld). If the
         indemnifying party shall have assumed the defense of a Third Party
         Claim, the indemnified party shall agree to any settlement, compromise
         or discharge of a Third Party Claim which the indemnifying party may
         recommend and which by its terms obligates the indemnifying party to
         pay the full amount of the liability in connection with such Third
         Party Claim, which releases the indemnifying party completely in
         connection with such Third Party Claim.

         The indemnification required by this Section XXII shall be made by
         periodic payments of the amount thereof during the course of the
         investigation or defense, as and when bills are received or loss,
         liability, claim, damage or expense is incurred. All claims under this
         Section XXII other than Third Party Claims shall be governed by Section
         XXII(6).


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<PAGE>

6.       Procedures Relating to Other Claims. In the event any indemnified party
         should have a claim against any indemnifying party under this Section
         XXII that does not involve a Third Party Claim being asserted against
         or sought to be collected from such indemnified party, the indemnified
         party shall deliver notice of such claim with reasonable promptness to
         the indemnifying party. The failure by any indemnified party to so
         notify the indemnifying party shall not relieve the indemnifying party
         from any liability which it may have to such indemnified party under
         this Section XXII, except to the extent that the indemnifying party
         demonstrates that it has been materially prejudiced by such failure. If
         the indemnifying party does not notify the indemnified party within 30
         calendar days following its receipt of such notice that the
         indemnifying party disputes its liability to the indemnified party
         under this Section XXII, such claim specified by the indemnified party
         in such notice shall be conclusively deemed a liability of the
         indemnifying party under this Section XXII and the indemnifying party
         shall pay the amount of such liability to the indemnified party on
         demand or, in the case of any notice in which the amount of the claim
         (or any portion thereof) is estimated, on such later date when the
         amount of such claim (or such portion thereof) becomes finally
         determined. If the indemnifying party has timely disputed its liability
         with respect to such claim, as provided above, the indemnifying party
         and the indemnified party shall proceed in good faith to negotiate a
         resolution of such dispute and, if not resolved through negotiations,
         such dispute shall be resolved by litigation in an appropriate court of
         competent jurisdiction.

SECTION XXIII. ASSIGNABILITY AND AMENDMENTS

1.       This Agreement and the rights and obligations hereunder shall not be
         assignable in whole or in part by any party without the prior written
         consent of the other parties hereto (such consent not to be
         unreasonably withheld or delayed); provided, however, that (i) subject
         to clause (ii) below, any party may assign its rights and obligations,
         in whole or in part, to an Affiliate of such party which (a) is
         Controlled by such party and (b) agrees in writing to be bound by the
         terms of this Agreement (including clause (ii) below); provided,
         however, that if GSK assigns this Agreement to an Affiliate, the
         Agreement will continue to be applicable to GSK and the GSK
         Subsidiaries, and (ii) upon such assignee ceasing to be an Affiliate of
         such party or an Affiliate Controlled by such party, such rights and
         obligations must be assigned back to such party or to another permitted
         assignee of such party and, in any event, the parties hereto agree that
         the original assignment shall have no further force and effect. Any
         transaction or series of transactions by which Quest or any of its
         respective Affiliates transfers, directly or indirectly, responsibility
         for, control of, or ownership of, the operations of Quest's clinical
         trials business to a third party, including through a management
         contract, a sale of assets, a business combination, liquidation,
         dissolution, merger or other transaction, shall constitute an
         assignment requiring GSK's prior written consent (such consent not to
         be unreasonably withheld or delayed). Should GSK withhold its consent
         to any transfer by Quest described


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<PAGE>

         above, and Quest elects to continue with such transfer, GSK shall have
         the right to immediately terminate this Agreement. Any attempted
         assignment in violation of this Section XXIII shall be void.

2.       No amendment, modification or waiver of this Agreement shall be
         effective unless it shall be in writing and signed by all the parties
         hereto.

SECTION XXIV. CHANGE IN CONTROL OF GSK

In the event of a Change in Control of GSK Parent, the successor company to GSK
as a result of such Change in Control (the "Successor Company") shall be
required to obtain Services under Section III of this Agreement in connection
with the conduct of Studies under this Agreement for any pharmaceutical compound
which immediately prior to the date of such Change in Control (the "Change in
Control Date") (a) GSK or any GSK Subsidiary owns or has interests in, or (b) is
in development by GSK or any GSK Subsidiary (the "Existing GSK Compounds"), in
each case to the extent such Services are required by the terms of Section III.
In addition, unless otherwise agreed by the JOC, the Successor Company shall not
be required to obtain Services required in connection with Studies as provided
under Section III for any pharmaceutical compound that is not an Existing GSK
Compound until and unless the initiation date of such Study is on or after the
date which is 18 months after the Change of Control Date. Notwithstanding the
foregoing, the Successor Company and Quest shall work together in good faith and
to the extent practicable under the circumstances to utilize Quest to provide
Services in connection with Studies for compounds in addition to Existing GSK
Compounds prior to the end of the 18-month period after the Change of Control
Date.

SECTION XXV. GOVERNING LAW

This Agreement shall be construed, interpreted and enforced under the laws of
the State of Delaware, regardless of the laws that might otherwise govern under
applicable principles of conflicts of laws thereof.

SECTION XXVI. INTERPRETATION

1.       The headings contained in this Agreement, in any Exhibit hereto, in any
         Task Description executed pursuant to this Agreement and in the table
         of contents to this Agreement are for reference purposes only and shall
         not affect in any way the meaning or interpretation of this Agreement.
         All Exhibits annexed hereto or referred to herein and all Addenda
         executed pursuant to this Agreement are hereby incorporated in and made
         a part of this Agreement as if set forth in full herein (e.g., any
         requirement for Quest to perform Services for any Study "pursuant to
         the terms set forth in this Agreement," is a requirement to perform
         such Services as set forth in the terms included in all Sections of
         this Agreement,


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<PAGE>

         in the relevant Task Description (including the relevant CLW) and in
         any Exhibit or Schedule to this Agreement). Any capitalized terms used
         in any Exhibit or Task Description but not otherwise defined therein,
         shall have the meanings set forth in this Agreement.

2.       The definitions of the terms herein shall apply equally to the singular
         and plural forms of the terms defined. Whenever the context may
         require, any pronoun shall include the corresponding masculine,
         feminine and neuter forms. The words "include", "includes" and
         "including" shall be deemed to be followed by the phrase "without
         limitation". The word "will" shall be construed to have the same
         meaning and effect as the word "shall". Unless the context requires
         otherwise (A) any definition of or reference to any agreement,
         instrument or other document herein shall be construed as referring to
         such agreement, instrument or other document as from time to time
         amended, supplemented or otherwise modified (subject to any
         restrictions on such amendments, supplements or modifications set forth
         herein), (B) any reference herein to any Person shall be construed to
         include the Person's successors and permitted assigns, (C) the words
         "herein", "hereof" and "hereunder", and words of similar import, shall
         be construed to refer to this Agreement in its entirety and not to any
         particular provision hereof, and (D) all references herein to
         paragraphs, Sections, Exhibits, or Addenda shall be construed to refer
         to paragraphs, Sections, Exhibits, Schedules and Addenda of this
         Agreement.

3.       All references to Quest's laboratory in the United Kingdom are hereby
         deemed to be references to any replacement laboratory Quest may
         establish in the future.

SECTION XXVII. NOTICES

All notices permitted or required to be given under the terms of this Agreement
shall be deemed to have been given when sent by telex or facsimile followed by
letter to the respective addresses of each party as indicated as set forth below
(or any new addresses with which as either party may provide the other party in
writing from time to time):

If to Quest:      Quest Diagnostics Incorporated
                  1200 Wall Street West, 6th Floor
                  Lyndhurst, NJ 07071
                  Attn: Vice President, Clinical Trials

With a required copy to:

                  Quest Diagnostics Incorporated
                  One Malcolm Avenue
                  Teterboro, NJ 07608-1070
                  Attn: General Counsel


                                       48

<PAGE>

                  201-393-6427
                  201-462-4795 (fax)

If to GSK:        GlaxoSmithKline
                  2301 Renaissance Blvd.
                  Mailstop REN 0310
                  King of Prussia, PA 19406-2772
                  Attn: Linda Meyerson
                        Vice President
                        Global Clinical Operations
                        610-787-3505

                  and

                  GlaxoSmithKline
                  Third Avenue
                  Harlow, Essex
                  CM19 5AW United Kingdom
                  Attn: Patrick Phillips
                  44-127-9-644086

With a required copy to:

                  GlaxoSmithKline
                  Corporate Law Department
                  709 Swedeland Road
                  P.O. Box 1539
                  King of Prussia, PA 19406
                  Attn: Edward J. Buthusiem, Esquire
                        Research and Development General Counsel
                        610-270-5605
                        610-270-5713(fax)

SECTION XXVIII. ENFORCEMENT

1.       Each party irrevocably submits to the exclusive jurisdiction of (a) any
         Federal court located in the Commonwealth of Pennsylvania and (b) any
         court of the Commonwealth of Pennsylvania, for the purposes of any
         suit, action or other proceeding arising out of this Agreement or any
         transaction contemplated hereby. Each party agrees to commence any
         action, suit, or proceeding relating hereto either in a Federal Court
         located in the Commonwealth of Pennsylvania or in a court of the
         Commonwealth of Pennsylvania. Each party further agrees that service of
         any process, summons, notice or document by U.S. registered mail to
         such party's address as listed in Section XXIX shall constitute
         effective service of process for any action, suit or proceeding in
         Pennsylvania with respect to any matters to which it has submitted to
         jurisdiction in this Section XXVIII. Each party


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<PAGE>

         irrevocably and unconditionally waives any objection to the laying of
         venue of any action, suit or proceeding arising out of this Agreement
         or the transactions contemplated hereby in (i) any Federal court
         located in the Commonwealth of Pennsylvania or (ii) any court of the
         Commonwealth of Pennsylvania, and hereby further irrevocably and
         unconditionally waives and agrees not to plead or claim in any such
         court that any such action, suit or proceeding brought in any such
         court has been brought in an inconvenient forum.

2.       Each party hereby waives to the fullest extent permitted by applicable
         law, any right it may have to a trial by jury in respect to any
         litigation directly or indirectly arising out of, under or in
         connection with this Agreement or any transaction contemplated hereby.
         Each party (a) certifies that no representative, agent or attorney of
         any other party has represented, expressly or otherwise, that such
         other party would not, in the event of litigation, seeks to enforce
         that foregoing waiver and (b) acknowledges that it and the other
         parties hereto have been induced to enter into this Agreement by, among
         other things, the mutual waivers and certifications in this Section
         XXVIII.

SECTION XXIX. INTEGRATION

This Agreement shall constitute the entire agreement between Quest and GSK
regarding the subject matter hereof.

                       [Signatures continue on next page]




                                       50

<PAGE>

         IN WITNESS WHEREOF, GSK and Quest have duly executed this Global
Clinical Trials Agreement as of the first day above written.


                                      SMITHKLINE BEECHAM PLC
                                      D/B/A GLAXOSMITHKLINE



                                      By /s/ Donald F. Parman
                                         -------------------------------------
                                         Name: Donald F. Parman
                                         Title: Attorney-in-Fact



                                        By /s/
                                           -------------------------------------
                                           Name:
                                           Title:


                                        QUEST DIAGNOSTICS INCORPORATED


                                      By /s/ Lucia Luce Quinn
                                         -------------------------------------
                                         Name: Lucia Luce Quinn
                                         Title: Senior V.P. -  Advanced
                                                Diagnostics




                                        By /s/
                                           -------------------------------------
                                           Name:
                                           Title:










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