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                                                                    EXHIBIT 10.3


                  FIRST AMENDMENT TO THE DISTRIBUTION AGREEMENT


This First Amendment (the "First Amendment") to the Distribution Agreement
between Digene Diagnostics, Inc. (now known as Digene Corporation) ("Digene")
and Murex Biotech Limited ("MBL") dated February 28, 1996 (the "Distribution
Agreement") serves to record certain changes mutually agreed between Digene and
MBL with respect to their respective performance under the Distribution
Agreement. Each of Digene and MBL may hereinafter be referred to as a "Party"
and collectively as the "Parties". This Agreement shall be effective as of
February 1, 1997.

1.       Definitions.

         1.1      "Affiliate" shall mean any Person that controls, is controlled
                  by or is under common control with MBL or Digene, as the
                  context may require. For purposes of this definition "control"
                  shall mean: (a) in the case of corporate entities, direct or
                  indirect ownership of at least fifty percent (50%) of the
                  stock or shares entitled to vote for the election of
                  directors; and (b) in the case of non-corporate entities,
                  direct or indirect ownership of at least fifty percent (50%)
                  of the equity interest with the power to direct the management
                  and policies of such non-corporate entities.

         1.2      "Agency and Sales Representation Agreement" shall mean the
                  Agency and Sales Representation Agreement dated of even date
                  herewith between Digene Corporation and Murex Diagnostics
                  Corporation.

         1.3      "Customer" shall mean any Person who purchases Exclusive
                  Products from MBL or any of its Affiliates in the Territory or
                  purchases Non-Exclusive Products from MBL or any of its
                  Affiliates in the Territory for HPV-testing purposes.

         1.4      "Digene/Murex Agreements" shall mean the following agreements:
                  (i) the Distribution Agreement dated May 19, 1992 between
                  Digene Diagnostics, Inc. and International Murex Technologies
                  Corporation ("IMTC"), as amended May 26, 1993 and April 4,
                  1996; (ii) the Development and License Agreement dated April
                  14, 1993 between Digene Diagnostics, Inc. and IMTC; and (iii)
                  the Development and License Agreement dated May 31, 1994
                  between Digene Diagnostics, Inc. and IMTC.

         1.5      "Effective Date" shall be the date first set forth herein.

         1.6      "Exclusive Products" shall mean the exclusive Products listed
                  on Schedule 1 attached hereto.

         1.7      "HPV" shall mean Human Papillomavirus.



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         1.8      "Non-Exclusive Products" shall mean the non-exclusive Products
                  listed on Schedule 1 attached hereto.

         1.9      "Person" shall mean an individual, a corporation, a
                  partnership, an association, a joint stock company, a trust,
                  any unincorporated organization or a government or political
                  subdivision thereof.

         1.10     "Products" shall mean the Exclusive Products and the
                  Non-Exclusive Products.

         1.11     "Territory" shall mean the countries listed on Schedule II
                  attached hereto.

2.       Cessation of Product Sales and Distribution.

         2.1      Except as set forth in the Agency and Sales Representation
                  Agreement and except as set forth in this Section 2, MBL and
                  its Affiliates will cease in the Territory, from the Effective
                  Date, the distribution and sale under the Distribution
                  Agreement of the Exclusive Products and the sale or other
                  distribution of the Non-Exclusive Products in connection with
                  the HPV Products or to Customers who intend to use such
                  Non-Exclusive Products for HPV-testing purposes. Nothing
                  contained herein, or in the Agency and Sales Representation
                  Agreement shall be deemed to terminate or otherwise reduce the
                  rights of MBL or any of its Affiliates to (i) sell or
                  otherwise distribute any of the Non-Exclusive Products in the
                  Territory in connection with non-HPV Digene products,
                  including to HPV Exclusive Product customers, or to non-HPV
                  Exclusive Products customers as such rights are set forth in
                  the Digene/Murex Agreements, or (ii) to sell or otherwise
                  distribute Products outside of the Territory pursuant to such
                  Digene/Murex Agreements.

         2.2      Digene is also hereby granted the right to request that MBL
                  cease the distribution and sale of the Products listed in
                  Schedule I attached hereto in any of the remaining territories
                  as listed in Exhibit B of the Distribution Agreement, provided
                  that Digene provides six (6) months advance notice to MBL of
                  the exercise of such right and further provided that such
                  request shall not conflict with the terms and provisions in
                  effect as of the Effective Date in any existing agency or
                  distribution agreement MBL or its Affiliates utilize to sell
                  or distribute the Products. In the event MBL or its Affiliates
                  elect to enter into any new agency or distribution agreement
                  with respect to the Products, MBL shall first notify Digene in
                  writing in advance. After such notification, Digene shall have
                  the right to accept or reject MBL's (or such MBL's
                  Affiliates') execution of such agreement. Digene shall have
                  the right to review the agreement or other arrangement between
                  MBL and such distributor or agent in order to confirm that
                  Digene's interests will be protected, and if necessary, in
                  Digene's sole discretion, provide for Digene to enter into an


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                  agreement directly with such agent or distributor. In such
                  event, MBL and MBL's Affiliates will have no obligation to
                  provide agency or other services under any agreements with
                  Digene or its Affiliates for servicing such distributor or
                  agent, except for services provided, at Digene's cost, to
                  reasonably support Digene during a transition period.

3.       Digene is relieved of any obligation under Sections 1.3 and 1.4 of the
         Distribution Agreement.

4.       Miscellaneous

         4.1      Arbitration. Subject to the provisions of the Federal
                  Arbitration Act, 9 U.S.C. Section 1 et. seq., any claim,
                  controversy or dispute arising out of or relating to this
                  Agreement or any interpretation or breach thereof or
                  performance thereunder, including without limitation any
                  dispute concerning the scope of this arbitration provision,
                  shall be settled by submission to final and binding
                  arbitration ("Arbitration") for determination, without any
                  right by any Party to a trial de novo in a court of competent
                  jurisdiction. The Arbitration and all pre-hearing, hearing,
                  post-hearing arbitration procedures shall be conducted in
                  accordance with the Commercial Arbitration Rules (the
                  "Commercial Rules") of the American Arbitration Association
                  (herein referred to as the "Association") as supplemented
                  hereby. The Arbitration hearing shall take place in
                  Washington, D.C. All pre-hearing and post-hearing matters and
                  procedures shall take place at such place and manner,
                  including telephonically, as shall be agreed by the Parties.
                  In the event the parties fail to reach agreement regarding the
                  foregoing, the chair of the Arbitration panel shall determine
                  the manner and location of such matters. In addition to the
                  Commercial Rules, the Parties shall also follow the procedures
                  described below:

                  4.1.1    The Party seeking Arbitration shall give notice of a
                           demand to arbitrate (herein referred to as the
                           "Demand") to the other Party and to the Association.
                           The Demand shall include (i) the nature of the claim
                           that is being asserted and the remedy or relief that
                           is requested, or the issues to be determined if no
                           claim is being asserted, (ii) a copy of this
                           arbitration provision, and (iii) unless the Parties
                           shall have otherwise agreed upon the mutual selection
                           of a single arbitrator, the designation of one
                           arbitrator, who shall have no prior or existing
                           personal or financial relationship with the
                           designating Party.

                  4.1.2    Within thirty (30) days after receipt of the Demand,
                           the other Party shall give notice (herein referred to
                           as the "Response") to the Party that demanded
                           arbitration, and to the Association, of (i) any
                           additional issues to be arbitrated, (ii) its answer
                           to the claims or issues raised by


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                           the Party that sent the Demand, and (iii) its
                           designation of a second arbitrator, who shall have no
                           prior or existing personal or financial relationship
                           with the designating Party.

                  4.1.3    If a Response designating a second arbitrator is not
                           received within the above-mentioned thirty (30) day
                           period, the Association shall immediately designate
                           the second arbitrator.

                  4.1.4    The two arbitrators as designated pursuant to the
                           foregoing provision shall then designate a third
                           arbitrator within ten (10) days after the designation
                           of the second arbitrator. If the two arbitrators
                           cannot agree on the designation of the third
                           arbitrator within the ten (10) day period allotted,
                           the Association shall designate the third arbitrator.
                           Such third arbitrator designated pursuant to this
                           Section 4.1.4 shall be the chair of the Arbitration
                           panel.

                  4.1.5    The Arbitration panel as designated above shall
                           proceed with the Arbitration by giving notice to all
                           Parties of its proceedings and hearings in accordance
                           with the Association's applicable procedures. Within
                           15 days after all three arbitrators have been
                           appointed or at such other time as shall be agreed by
                           the Parties, an initial meeting among the chair of
                           the Arbitration panel and counsel for the Parties
                           shall be held for the purpose of establishing a plan
                           for administration of the Arbitration, including: (i)
                           definition of issues; (ii) scope, timing and type of
                           discovery, which may at the discretion of the
                           arbitrators include production of documents in the
                           possession of the Parties, but may not, without the
                           consent of the Parties, include depositions; (iii)
                           exchange of documents and filing of detailed
                           statements of claims and pre-hearing memoranda; (iii)
                           schedule and place of hearings; and (iv) any other
                           matters that may promote the efficient, expeditious
                           and cost-effective conduct of the proceeding. The
                           substantive law of the State of Maryland shall be
                           applied by the arbitrators to the resolution of the
                           dispute, provided that the arbitrators shall base
                           their decision on the express terms, covenants and
                           conditions of this Agreement. The arbitrators shall
                           be bound to make specific findings of fact and reach
                           conclusions of law, based upon the submissions and
                           evidence of the Parties, and shall issue a written
                           decision explaining the basis for the decision and
                           award.

                  4.1.6    The Parties agree that the arbitrators shall have no
                           power to alter or modify any express provision of
                           this Agreement or to render any award which, by its
                           terms, effects any such alteration or modification.



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                  4.1.7    Upon written demand to any Party to the Arbitration
                           for the production of documents and things (including
                           computer discs and data) reasonably related to the
                           issues being arbitrated, the Party upon which such
                           demand is made shall promptly produce, or make
                           available for inspection and copying, such documents
                           or things without the necessity of any action by the
                           arbitrators, provided, however, that no such demand
                           shall be effective if made within the twenty (20) day
                           period prior to the first day of the Arbitration
                           hearing.

                  4.1.8    Subject to the limitations imposed by Section 4.1.5,
                           the arbitrators shall have the power to grant any and
                           all relief and remedies, whether at law or in equity,
                           including provisional relief, that the courts in the
                           State of Maryland may grant and such other relief as
                           may be available under the Commercial Rules, other
                           than punitive damages. Any award of the arbitrators
                           shall include pre-award and post-award interest at
                           the applicable rate or rates under Maryland law. The
                           decision of the arbitrators shall be final and as an
                           "award" within the meaning of the Commercial Rules
                           and the Federal Arbitration Act and judgment upon the
                           arbitration award may be entered in the United States
                           District Courts of Maryland ("Maryland District
                           Courts") or any other court having jurisdiction, as
                           if it were a judgment of that court. The Parties to
                           this Agreement expressly consent to the jurisdiction
                           of the Association, including, without limitation,
                           reasonable attorney's fees and the Parties waive any
                           objection they may have as to jurisdiction and venue
                           regarding the Maryland District Courts.

                  4.1.9    The Arbitration panel is specifically authorized to
                           award attorney's fees and expenses to the prevailing
                           Party, as determined by the Arbitration panel.

         4.2      Entire Agreement.

                  This First Amendment, along with the Distribution Agreement,
                  as amended by this First Amendment thereto, set forth the
                  entire agreement and understanding between the Parties
                  relative to the subject matter contained herein and therein
                  and supersede all other agreements, oral and written,
                  heretofore made between the Parties, with respect to the
                  subject matter contained herein and therein. Any amendment
                  hereto must be in writing and signed by an authorized
                  representative of each of Digene and MBL.

         4.3      Captions. Section titles or captions contained herein are for
                  reference only and shall not be considered in construing this
                  Agreement.



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         4.4      Notices. All notices and requests required or authorized
                  hereunder, shall, except where specifically provided
                  otherwise, be given in writing, and delivered either by
                  personal delivery to the Party to whom notice is to be given,
                  or sent by registered mail or by an internationally recognized
                  express delivery service, addressed to the Party intended at
                  the address set forth below. The date of delivery in the case
                  of personal or mail delivery or the date upon which it is
                  deposited with the express delivery service in the case of
                  notice by express delivery service, shall be deemed to be the
                  date of such notice.

                  Digene:           Digene Corporation
                                    9000 Virginia Manor Road
                                    Beltsville, MD 20705
                                    Attn:  President or Executive Vice President

                  MBL:              Murex Biotech Limited
                                    Central Road
                                    Temple Hill, Dartford, Kent DA1 5LR
                                    Attn:  Vice President and General Manager

         4.5      Waivers. The waiver by either Party of any breach or alleged
                  breach of any provision hereunder shall not be construed to be
                  a waiver of any concurrent, prior or succeeding breach of said
                  provision or any other provision herein. Any waiver must be in
                  writing.

         4.6      Governing Law. This First Amendment, and all of the rights and
                  duties in connection therewith, shall be governed by and
                  construed under the law of the State of Maryland, U.S.A.,
                  without regard to conflicts of laws principles, applicable to
                  agreements made and to be performed in that State.

         4.7      Press Release and Other Permitted Disclosures Regarding the
                  First Amendment.

                  4.7.1    Press Releases. Each of Digene and MBL agree not to
                           announce this First Amendment by press release or
                           other form of communication without the written
                           approval of the other Party.

                  4.7.2    Permitted Disclosure. The Parties agree to keep the
                           terms of this First Amendment confidential with
                           exception of such information which in the opinion of
                           counsel to the disclosing party is required to be
                           disclosed by applicable law, rule, regulation or
                           generally accepted accounting practice, including any
                           rules of applicable stock exchanges and other
                           self-regulatory authorities or organizations on which
                           the Parties or their Affiliates are listed. Provided,
                           however, that in the event a Party or its


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                           Affiliates shall be required to disclose any of the
                           terms of this First Amendment, whether pursuant to
                           subpoena, deposition, interrogatory, or otherwise, or
                           a Party or its Affiliates shall otherwise propose to
                           disclose any of the terms of this First Amendment
                           (except in connection with such Party's or such
                           Affiliates' required disclosure under any applicable
                           securities laws, the rules of any applicable stock
                           exchange or other self regulatory authority or
                           organization or other reporting requirements) such
                           disclosing Party shall provide the other Party with
                           prompt written notice of such requirement so that the
                           other Party may seek a protective order or other
                           appropriate remedy and/or waive compliance with the
                           terms of this First Amendment. Notwithstanding the
                           foregoing, except as otherwise required by the
                           provisions of Section 4.7.1 hereof, (i) no prior
                           written notice shall be required in connection with
                           any Party's (or its Affiliates') required compliance
                           with applicable securities laws, the rules of any
                           applicable stock exchange or other self-regulatory
                           authority or organization or other reporting
                           requirements; and (ii) any Party shall be permitted
                           to submit this First Amendment as evidence in any
                           proceeding in connection with any dispute between the
                           Parties. The provisions of this Section 4.7.2 shall
                           not restrict a Party or its Affiliates from making
                           any disclosure of any terms of this First Amendment
                           to the extent such terms become generally available
                           to the public (other than as a result of a disclosure
                           by such Party in violation of this First Amendment),
                           or restrict the ability of the Parties and their
                           Affiliates from making disclosure to the extent such
                           disclosure is required for the effective undertaking
                           by the Parties of their respective rights and
                           obligations hereunder. By way of example and not in
                           limitation of the foregoing, MBL shall be entitled to
                           disclose to proposed customers the fact that it is
                           acting as an authorized distributor of the Products
                           or agent of Digene.

         4.8      Counterparts. This First Amendment shall be executed in
                  counterparts, each of which shall be deemed an original but
                  both of which together shall constitute the same instrument.

         4.9      All references to "Digene Diagnostics, Inc." under the
                  Distribution Agreement shall hereafter be changed to
                  references to "Digene Corporation".

         4.10     Conflict; Effectiveness of Distribution Agreement. In the
                  event of conflict between the provisions of this First
                  Amendment and the Distribution Agreement with respect to the
                  subject matter herein, this First Amendment shall control. All
                  other terms and provisions of the Distribution Agreement
                  remain in full force and effect.




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                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]



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         In consideration of the mutual covenants and conditions herein set
forth, the Parties have executed this First Amendment as of the Effective Date.


Accepted and agreed for and on behalf of Digene Corporation


By /s/ EVAN JONES                                Date       3/3/97
  --------------------------------------             --------------------

Print Name Evan Jones
          ------------------------------ 


Accepted and agreed for and on behalf of Murex Biotech Limited


By /s/ R. PETER SILVESTON                       Date        2/1/97
  ---------------------------------------           ---------------------


Print Name R. Peter Silveston
          -------------------------------


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                              SCHEDULE I - PRODUCTS
                               EXCLUSIVE PRODUCTS

<TABLE>
<CAPTION>
                                                                               Digene Part
Exclusive Product Description                                                  Number*
-----------------------------                                                  -------
<S>                                                                            <C>
HUMAN PAPILLOMAVIRUS DETECTION KIT
Human Papillomavirus (HPV) DNA Assay (6/11/42/43/44 and                        4401-1030
16/18/31/35/45/51/52/56)
HPV DNA Test Panel                                                             4401-1024
Digene Specimen Collection Kit                                                 4203-0020
Digene Sample Transport Medium                                                 4203-1030
Human Papillomavirus (HPV) Target: LI Region (Consensus)                       4603-1100
Probe Groups (6/11/42/43/44 and
16/18/31/35/39/45/51/52/56/68)

INDIVIDUAL HPV PROBE PACKS:
HPV Type 6/11                                                                  4401-1611
HPV Type 16                                                                    4401-1016
HPV Type 18                                                                    4401-1018
HPV Type 31                                                                    4401-1031
HPV Type 33                                                                    4401-1033
HPV Type 35                                                                    4401-1035
HPV Type 42                                                                    4401-1042
HPV Type 43                                                                    4401-1043
HPV Type 44                                                                    4401-1044
HPV Type 45                                                                    4401-1045
HPV Type 51                                                                    4401-1051
HPV Type 52                                                                    4401-1052
HPV Type 56                                                                    4401-1056
</TABLE>



                             NON-EXCLUSIVE PRODUCTS

<TABLE>
<CAPTION>
                                                                               Digene Part
Non-Exclusive Product Description                                              Number*
---------------------------------                                              -------
<S>                                                                            <C>
HYBRID CAPTURE SYSTEM EQUIPMENT AND ACCESSORIES
DCR-1 Luminometer                                                              4300-1010
Rotary Shaker Assembly (22v)                                                   4300-1025
Printer Paper (DCR-1 Compatible)                                               4300-1012
Wash Apparatus                                                                 4301-1001
Decanting Racks                                                                4301-1002
Hybridization Rack                                                             4301-1003
Disposable Transfer Pipettes                                                   4301-1500
Luminometer Validation Reagents                                                4400-1000
Hybridization Tube Caps (red)                                                  4400-1040
Hybridization Tube Caps (green)                                                4400-1041
SHARP Signal System Assay                                                      4600-1192
</TABLE>


--------

*        Represents all current products within such part number category.


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                             SCHEDULE II - TERRITORY


         EUROPE

Germany
Switzerland
Austria
Belgium
Netherlands
Luxembourg
France
Italy
Spain
United Kingdom


EASTERN EUROPE

Poland
Czech and Slovak Republics
Hungary
Romania
Commonwealth of Independent States
Bulgaria
Estonia
Slovenia
Croatia
Macedonia
Lithuania