<PAGE>



                                                           EXHIBIT 10.1





                                  LICENSE AGREEMENT

                                       BETWEEN

                             AVID CORPORATION (LICENSEE)

                                         AND

                                   THE DUPONT MERCK
                          PHARMACEUTICAL COMPANY (LICENSOR)











*** Certain confidential portions of this Exhibit were omitted by means
of blackout of the text (the "Mark"). This Exhibit has been filed separately
with the Secretary of the Commission without the Mark pursuant to the
Company's Application Requesting Confidential Treatment under Rule 24b-2
under the 1934 Act.


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                                  TABLE OF CONTENTS

                                                                          Page
                                                                          ----
I.    DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . .  1
      1.01       "Affiliate" . . . . . . . . . . . . . . . . . . . . . . .  2
      1.02       "Agency". . . . . . . . . . . . . . . . . . . . . . . . .  2
      1.03       "Calendar Quarter". . . . . . . . . . . . . . . . . . . .  2
      1.04       "Calendar Year" . . . . . . . . . . . . . . . . . . . . .  2
      1.06       "Field" . . . . . . . . . . . . . . . . . . . . . . . . .  2
      1.07       "First Commercial Sale" . . . . . . . . . . . . . . . . .  2
      1.08       "IND" . . . . . . . . . . . . . . . . . . . . . . . . . .  2
      1.09       "Know-How". . . . . . . . . . . . . . . . . . . . . . . .  3
      1.10       "Licensed Compound" . . . . . . . . . . . . . . . . . . .  3
      1.11       "Licensed Product". . . . . . . . . . . . . . . . . . . .  3
      1.12       "NDA" . . . . . . . . . . . . . . . . . . . . . . . . . .  3
      1.13       "Net Sales" . . . . . . . . . . . . . . . . . . . . . . .  3
      1.14       "Patent Rights" . . . . . . . . . . . . . . . . . . . . .  4
      1.15       "Confidential Information". . . . . . . . . . . . . . . .  4
      1.16       "Sublicensee" . . . . . . . . . . . . . . . . . . . . . .  4
      1.17       "Territory" . . . . . . . . . . . . . . . . . . . . . . .  4
      1.18       "Valid Patent Claim". . . . . . . . . . . . . . . . . . .  4

II.   GRANT OF LICENSE . . . . . . . . . . . . . . . . . . . . . . . . . .  5
      2.01       Grant By DuPont Merck . . . . . . . . . . . . . . . . . .  5
      2.02       Reservation . . . . . . . . . . . . . . . . . . . . . . .  5

III.  PAYMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  5
      3.01       Licensee's Up Front Payment . . . . . . . . . . . . . . .  5
      3.02       Licensee's Milestones . . . . . . . . . . . . . . . . . .  5
      3.03       Licensee's Royalties. . . . . . . . . . . . . . . . . . .  6
      3.04       Licensee's Annual License Preservation Fee to Licensor. .  6
      3.05       In The Event of Sublicense by Licensee. . . . . . . . . .  7
      3.06       Payment and Exchange Rate . . . . . . . . . . . . . . . .  8

IV.   RECORDS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  9
      4.01       Reports . . . . . . . . . . . . . . . . . . . . . . . . .  9
      4.02       Books and Records . . . . . . . . . . . . . . . . . . . .  9
      4.03       Sublicensees. . . . . . . . . . . . . . . . . . . . . . .  9

V.    DEVELOPMENT OF LICENSED PRODUCT. . . . . . . . . . . . . . . . . . . 10
      5.01       Product Development . . . . . . . . . . . . . . . . . . . 10
      5.02       Development Schedule. . . . . . . . . . . . . . . . . . . 10
      5.03       Data Transfer . . . . . . . . . . . . . . . . . . . . . . 10
      5.04       Periodic Updates. . . . . . . . . . . . . . . . . . . . . 11

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VI.   PATENT MAINTENANCE/PATENT INFRINGEMENT . . . . . . . . . . . . . . . 11
      6.01       Patent Maintenance. . . . . . . . . . . . . . . . . . . . 11
      6.02       Reimbursement By Licensee . . . . . . . . . . . . . . . . 11
      6.03       Notice of Infringement. . . . . . . . . . . . . . . . . . 11
      6.04       Licensor's Right to Bring Suit. . . . . . . . . . . . . . 12
      6.05       Licensee's Right to Bring Suit. . . . . . . . . . . . . . 12
      6.06       Litigation Expenses . . . . . . . . . . . . . . . . . . . 12

VII.  NOTICES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
      7.01       Notices . . . . . . . . . . . . . . . . . . . . . . . . . 13
      7.02       Payments. . . . . . . . . . . . . . . . . . . . . . . . . 13

VIII. INDEMNIFICATION. . . . . . . . . . . . . . . . . . . . . . . . . . . 14
      8.01       Indemnification by Licensee . . . . . . . . . . . . . . . 14
      8.02       Procedure . . . . . . . . . . . . . . . . . . . . . . . . 15
      8.03       Insurance . . . . . . . . . . . . . . . . . . . . . . . . 15
      8.04       Warranty. . . . . . . . . . . . . . . . . . . . . . . . . 15

IX.   TERM; TERMINATION. . . . . . . . . . . . . . . . . . . . . . . . . . 16
      9.01       Term and Expiration . . . . . . . . . . . . . . . . . . . 16
      9.02       Termination for Breach. . . . . . . . . . . . . . . . . . 16
      9.03       Termination by Licensee . . . . . . . . . . . . . . . . . 16
      9.04       Termination by Licensor . . . . . . . . . . . . . . . . . 17
      9.05       On Termination or Expiration. . . . . . . . . . . . . . . 17
      9.06       Survival of Certain Obligations . . . . . . . . . . . . . 17
      9.07       Paid-up License . . . . . . . . . . . . . . . . . . . . . 18

X.    CONFIDENTIALITY. . . . . . . . . . . . . . . . . . . . . . . . . . . 18
      10.01      Nondisclosure Obligation. . . . . . . . . . . . . . . . . 18
      10.02      Use of Confidential Information . . . . . . . . . . . . . 19
      10.03      Publication . . . . . . . . . . . . . . . . . . . . . . . 19

XI.   MISCELLANEOUS. . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
      11.01      Modifications . . . . . . . . . . . . . . . . . . . . . . 20
      11.02      Waiver. . . . . . . . . . . . . . . . . . . . . . . . . . 20
      11.03      Assignment. . . . . . . . . . . . . . . . . . . . . . . . 20
      11.04      Severability. . . . . . . . . . . . . . . . . . . . . . . 20
      11.05      Headings. . . . . . . . . . . . . . . . . . . . . . . . . 20
      11.06      Applicable Law/Jurisdiction . . . . . . . . . . . . . . . 20
      11.07      Force Majeure . . . . . . . . . . . . . . . . . . . . . . 21
      11.08      Entire Agreement. . . . . . . . . . . . . . . . . . . . . 21
      11.09      Counterparts. . . . . . . . . . . . . . . . . . . . . . . 21
      11.10      Use of Names. . . . . . . . . . . . . . . . . . . . . . . 21
      11.11      Independent Contractors . . . . . . . . . . . . . . . . . 21
      11.12      Representations and Warranties. . . . . . . . . . . . . . 22
      11.13      Publicity . . . . . . . . . . . . . . . . . . . . . . . . 22

                                      -ii-
<PAGE>

                                LICENSE AGREEMENT

    This License Agreement, effective as of the date of last signature, by a 
party hereto (the "Effective Date"), is entered into by and between Avid 
Corporation, a corporation organized and existing under the laws of the 
Commonwealth of Pennsylvania, and its Affiliates (collectively, "Licensee") 
and The DuPont Merck Pharmaceutical Company ("Licensor"), a general 
partnership organized and existing under the laws of the State, of Delaware.

    WHEREAS, Licensor and Licensee entered into that certain Exclusive Option 
Agreement ("Option Agreement") dated March 7, 1996, whereby Licensor granted 
Licensee an exclusive, worldwide option to enter into an exclusive, worldwide 
license Agreement covering the development and commercialization of Licensed 
Compound.

    WHEREAS, Licensee has now exercised the option granted in the Option 
Agreement and duly so notified DuPont Merck in a letter dated November 11, 
1996; and

    WHEREAS, Licensor desires to grant, and Licensee desires to receive, an 
exclusive, worldwide license to make, have made, import, use and sell 
Licensed Product, under the circumstances, set forth below;

    NOW THEREFORE, intending to be legally bound, Licensor and Licensee 
hereby covenant and agree as follows:

                                I.  DEFINITIONS

    The terms in this Agreement with initial letters capitalized, whether used 
    in the singular or plural, shall have the meaning designated below or, if 
    not designated below, the meaning as designated in places throughout this 
    Agreement.

                                      -1-
<PAGE>

1.01   "Affiliate" means any corporation or other entity which controls, is 
       controlled by, or is under common control with a party to this 
       Agreement. A corporation or other entity shall be regarded as in 
       control of another corporation or entity if it owns or directly or 
       indirectly controls fifty percent (50%) or more of the voting stock or 
       other ownership interest of the other corporation or entity, or if it 
       possesses, directly or indirectly, the power to direct or cause the 
       direction of the management and policies of the corporation or other 
       entity or the power to elect or appoint fifty percent (50%) or more of 
       the members of the governing body of the corporation or other entity.

1.02   "Agency" means any governmental regulatory authority responsible for 
       granting health or pricing approvals, registrations, import permits, 
       and other approvals required before Licensed Product may be tested or 
       marketed in any country.

1.03   "Calendar Quarter" means the respective periods of three (3) 
       consecutive calendar months ending on March 31, June 30, September 30 
       and December 31.

1.04   "Calendar Year" means each successive period of twelve (12) months 
       commencing on January 1 and ending on December 31.

1.06   "Field" means prophylactic and/or therapeutic treatment of patients 
       suffering from human immunodeficiency virus ("HIV"), acquired 
       immunodeficiency disease ("AIDS") and/or AIDS-related diseases.

1.07   "First Commercial Sale" means, with respect to a Licensed Product, the 
       first sale for use or consumption by the public of such Licensed 
       Product in a country after all required approvals, including marketing 
       and pricing approvals, have been granted by the governing health 
       authority of such country.

1.08   "IND" means Investigational New Drug application, or the like, as 
       defined in the applicable laws and regulations of the governmental 
       drug regulatory agencies in each country in the Territory.

                                      -2-
<PAGE>

1.09   "Know-How" means all information and materials, including but not 
       limited to, technology, experience, discoveries, improvements, 
       processes, formulae, data (including but not limited to all 
       preclinical, clinical, toxicological, and pharmacological data) and 
       inventions, know-how and trade secrets, patentable or otherwise, which 
       on the Effective Date of this Agreement are in Licensor's possession 
       or control, are not generally known and are necessary or useful for 
       Licensee in the research, development, manufacture, marketing, use or 
       sale of Licensed Product for the Field in the Territory.  Know-How 
       shall not include any such data or information which is available to 
       Licensor under a license pursuant to which Licensor does not have the 
       light to grant sublicenses.

1.10   "Licensed Compound" means Licensor's protease inhibitor for treatment 
       of human immunodeficiency virus ("HIV"), which is known as DMP450, and 
       which has the chemical name, [4R-(4a,5a,6b,7b)]-hexahydro-5,6-
       bis(hydroxy)-1,3-bis[(3-aminophenyl)methyl]-4,7 -bis(phenylmethyl)-
       2H-1,3-diazepin-2-one, bis-methanesulfonic acid salt.

1.11   "Licensed Product" means a formulation for human pharmaceutical use in 
       unit dosage form comprising Licensed Compound the manufacture, import, 
       use or sale of which would infringe a Valid Patent Claim but for the 
       license provided under Article 11 hereinbelow.

1.12   "NDA" means either the accelerated or regular new drug application 
       filed in the U.S. or the corresponding application for authorization 
       for marketing of Licensed Product in any other country, as defined in 
       the applicable laws and regulations and filed with the Agency of a 
       given country in the Territory.

1.13   "Net Sales" means the aggregate gross invoice price of Licensed 
       Product sold by LICENSEE, its Affiliates and Sublicensees to an 
       independent third party after deducting (to the extent not already 
       deducted in the amount invoiced):

                                      -3-
<PAGE>

       (i)    trade and quantity discounts;
       (ii)   returns and allowances; and
       (iii)  rebates, chargebacks and other amounts paid, credited or accrued.

1.14   "Patent Rights" means the patents and patent applications listed on 
       Exhibit A and any and all patents and patent applications owned by or 
       licensed to Licensor as of the Effective Date, which contain one or 
       more claims directed to Licensed Product for the Field, and any and 
       all divisions, continuations, continuations-in-part, reissues, 
       renewals, extensions or the like of any such patents and patent 
       applications and all foreign equivalents thereof.  Patent Rights shall 
       not include any patents or patent rights available to Licensor under a 
       license pursuant to which Licensor does not have the light to grant 
       sublicenses.  It is understood that Licensor shall not assert against 
       Licensee any other patent rights it may now possess or it acquires in 
       the future as they relate to the manufacture, importation, use or and 
       sale of Licensed Compound and Licensed Product.

1.15   "Confidential Information" means and includes, without limitation, 
       information and data of one party supplied to the other, know-how, and 
       all other scientific, clinical, regulatory, marketing, financial and 
       commercial information or data, whether communicated in writing or 
       orally or by other means, which is provided by one party to the other 
       party in connection with this Agreement.

1.16   "Sublicensee" means a business entity which is sublicensed by Licensee 
       under this Agreement.

1.17   "Territory" means the entire world.

1.18   "Valid Patent Claim" means a claim of an issued and unexpired patent 
       included within Patent Rights which, but for the license provided 
       under Article II hereof, would be infringed by Licensee's manufacture, 
       use, sale or import of Licensed Product, and which has not been 
       revoked or held unenforceable or invalid by a decision of a court

                                      -4-
<PAGE>

       or other governmental agency of competent jurisdiction, unappealable 
       or unappealed within the time allowed for appeal, or which has not 
       been disclaimed, denied or admitted to be invalid or unenforceable 
       through reissue or disclaimer or otherwise.

                              II. GRANT OF LICENSE

2.01   GRANT BY DUPONT MERCK  Subject to the reservation of Section 2.02, 
       Licensor hereby grants Licensee an exclusive license, with right to 
       sublicense, for the Field under the Patent Rights and Know-How to 
       make, have made, import, use and sell Licensed Compound and Licensed 
       Product in the Territory.

2.02   RESERVATION  DuPont Merck expressly reserves the right to make and use 
       Licensed Compound in its internal research programs.

                                III.  PAYMENTS

3.01   LICENSEE'S UP FRONT PAYMENT - In consideration of the rights granted 
       Licensee in 2.01 hereinabove, Licensee shall pay Licensor an initial 
       license fee equal to one million seven hundred fifty thousand dollars 
       ($1,750,000.00)(the "Initial License Fee").  Said Initial License Fee 
       shall be due on the Effective Date, and shall not be returnable in any 
       event, nor shall it be creditable against earned royalties.

3.02   LICENSEE'S MILESTONES - Licensee shall make the following payments to 
       Licensor on achievement of the following milestones:

                             ***

                             ***

                             ***



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                             ***
                             ***
                             ***
                             ***
                             ***

                             ***
                             ***

                             ***
                             ***

       ***   of all milestone payments shall be             ***              
       but no single royalty payment shall be reduced by more than    ***   
       Licensee shall notify Licensor in writing within thirty (30) days upon 
       the achievement of each milestone event and such milestone payment 
       shall be paid no later than        ***    following achievement of the 
       milestone event.

3.03   LICENSEE'S ROYALTIES - As further consideration for the rights and 
       licenses granted herein, Licensee shall pay Licensor a royalty equal 
       to        ***   of Licensee's and/or Licensee's Affiliates annual Net 
       Sales following First Commercial Sale of License Product, the 
       manufacture, importation, use or sale of which would, but for the 
       licenses granted hereunder, infringe a Valid Patent Claim.

3.04   LICENSEE'S ANNUAL LICENSE PRESERVATION FEE TO LICENSOR - In the event 
       that Licensee's total payments to Licensor in any calendar year 
       commencing with 1998, whether in the form of royalties, milestones, or 
       Additional Payment (as this term defined below), do not at least equal 
       the Annual License Preservation Fees set forth below, Licensee, as a 
       condition of maintaining the exclusivity of the licenses granted 
       hereunder, shall by the end of the calendar year in question pay the 
       difference between the Annual License


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                                      -6-
<PAGE>

       Preservation Fee specified below and the total of royalties, 
       milestones and Additional Payments made to Licensor that year 
       (hereafter, the "Unpaid Difference");

       Annual License Preservation Fee              Calendar Year
       -------------------------------              -------------

                ***                                 ***


                ***                                 ***

                ***                                 ***

                ***                                 ***




       The Unpaid Difference in any given calendar year shall be Paid by 
       Licensee to Licensor in cash, provided however, that up to     ***   
       of the Unpaid Difference in each of             ***            
       may, at Licensee's election, be paid to Licensor in the form of 
       Licensee's stock valued at the then prevailing fair market price for 
       such stock and having those rights and preferences as mutually agreed 
       upon by the parties.  The fair market price will be determined as the 
       average price of Licensee's stock for the prior thirty (30) days if 
       Licensee stock is on a major exchange.  If Licensee's stock is not 
       traded on a major exchange, the fair market price will be the price of 
       Licensee's stock as determined in its most recent private placement.  
       If royalties, milestones or Additional Payments in any given year 
       exceed the Annual License Preservation Fee, the excess shall be 
       carried over and applied against the ensuing year(s)' Annual License 
       Preservation Fee.


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                                      -7-
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3.05   IN THE EVENT OF SUBLICENSE BY LICENSEE - Licensee has the right to 
       sublicense the rights granted it hereunder to unrelated, unaffiliated 
       third parties, after obtaining the prior written consent of DuPont 
       Merck, such consent not to be unreasonably withheld.  In the event 
       Licensee enters into such a sublicense agreement, then Licensee shall 
       pay Licensor     ***    of the cash equivalent of any license fee and 
       technology premium equity payment that Licensee receives from its 
       Sublicensee ("Additional Payment"). As used herein, technology premium 
       equity payment means A(B-C), where A is the number of shares of 
       Licensee's stock purchased by the Sublicensee, B is the share price 
       paid by the Sublicensee, and C is the share price paid by the most 
       recent non-pharmaceutical investor to purchase at least        *** 
             ***   of the same type of Licensee stock, or, if Licensee is 
       publicly traded, then C is the average trading price of Licensee's 
       stock for the ten business days immediately prior to the transaction.  
       Moreover, Licensee shall pay Licensor     ***      of all milestones 
       that licensee receives from its Sublicensee.  This     ***      share 
       shall be applied against, but will not excuse Licensee from, the above 
       milestone obligations (i.e. Licensor shall receive the greater of its  
          ***    share of Licensee's milestones or the milestones specified 
       above).  Also, Licensee shall pay Licensor a royalty equal to the 
       greater of       ***      of the royalties that Licensee receives from 
       its Sublicensee(s) or     ***        of the Sublicensee(s)' Net Sales 
       following First Commercial Sale of Licensed Product, the manufacture, 
       importation, use or sale of which would, but for the licenses granted 
       hereunder, infringe a Valid Patent Claim.

3.06   PAYMENT AND EXCHANGE RATE - All payments to be made under this 
       Agreement shall be made in United States dollars and shall be paid by 
       bank wire transfer in immediately available funds as provided in 
       Section 7.02 hereinbelow or to such other bank account in the United 
       States designated in writing by DuPont Merck.  In the case of sales 
       outside the United States, the rate of exchange to be used in 
       computing the amount of currency equivalent in United States dollars 
       due shall be the month-end exchange rate applicable for the month in 
       which the sales are recorded.  Such month-end rate of


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                                      -8-
<PAGE>

       exchange shall be the rate prevailing at the close of the last 
       business day of the month as identified by THE WALL STREET JOURNAL. If 
       royalties are paid outside the U.S., Licensee shall use all reasonable 
       efforts to help Licensor obtain the lowest tax rate possible under the 
       applicable international treaty with the U.S.

                                 IV.  RECORDS

4.01   REPORTS - During the term of the Agreement following the First 
       Commercial Sale of a Licensed Product, Licensee shall furnish to 
       Licensor a quarterly written report for the Calendar Quarter stating 
       the gross sales price and the Net Sales (including a listing of 
       deductions) of all Licensed Product(s) sold by Licensee, its 
       Affiliates and its Sublicensees in the Territory during the reporting 
       period and the royalties payable under this Agreement.  Reports shall 
       be due on the      ***     following the close of each Calendar 
       Quarter.  Royalties shown to have accrued by each royalty report shall 
       be due and payable on the date such royalty report is due.

4.02   BOOKS AND RECORDS - Licensee agrees to keep full and accurate books of 
       account, records, data and memoranda regarding the sales of the 
       Product in sufficient detail to enable the payments due to Licensor 
       hereunder to be determined.  Licensee grants Licensor the right, at 
       its own expense, to examine said books and records insofar as they 
       concern the Product once in any calendar year for the purpose of 
       verifying the reports provided for in this Agreement.  Licensee shall 
       retain such records for  ***   ***.  If Licensor examines the records, 
       documents and materials in the possession or under the control of 
       Licensee, such examination shall be conducted during normal business 
       hours in such manner as to not unduly interfere with Licensee's 
       business.  Licensor and its representatives shall not disclose to any 
       other person, firm, or corporation any information acquired as a 
       result of any such examination, provided, however. that nothing 
       contained herein shall be construed to prevent Licensor and/or its 
       duly authorized representatives from testifying in any court or 
       tribunal of competent


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                                      -9-
<PAGE>

       jurisdiction with respect to the information obtained as a result of 
       such examination in any action instituted to enforce Licensor's rights 
       under the terms of this Agreement.  If any audit by Licensor discloses 
       a discrepancy of more than    ***    in the amount paid to Licensor 
       and the amount actually owed to Licensor, Licensee shall reimburse 
       Licensor for the reasonable actual costs of such audit and shall 
       promptly pay the discrepancy to Licensor, plus interest thereon at 
            ***       from the date such amount was originally due.

4.03   SUBLICENSEES. - Licensee shall include in each sublicense granted by 
       it pursuant to this Agreement a provision requiring the Sublicensee to 
       make reports to Licensee, to keep and maintain records of sales made 
       pursuant to such sublicense and to grant access to such records by 
       Licensor's independent accountant to the same extent required of 
       Licensee under this Agreement.

                     V.  DEVELOPMENT OF LICENSED PRODUCT

5.01   PRODUCT DEVELOPMENT - Licensee shall be responsible, at its own cost 
       and expense, for the development and commercialization of Licensed 
       Product. Licensee shall use its    ***  to develop the Licensed 
       Product.  As used herein the term          ***           
                             ***
                             ***
       ***  Licensee shall diligently perform or cause to be performed     
       all research and development necessary to obtain and maintain in full 
       force     and effect Agency approval in                ***
                             ***
                             ***

       ***  Licensee shall at the earliest possible time, consistent with 
       sound scientific and business principles, Cite applications for Agency 
       approval to sell Licensed Products in                  ***
                             ***
                             ***

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                                      -10-
<PAGE>

5.02   DEVELOPMENT SCHEDULE - Attached hereto as Exhibit B is an initial 
       Development Schedule outlining the Licensed Product development plan 
       for the United States market.  The Development Schedule may be 
       modified periodically as mutually agreed to, in writing, by the 
       parties.  Licensee's substantial compliance with the Development 
       Schedule, as it may be amended from time to time, shall be deemed to 
       satisfy the ***           ***          referred to in Section 5.01, 
       above.

5.03   DATA TRANSFER - To the extent not provided during the term of the 
       Option Agreement, Licensor shall provide Licensee with existing 
       pre-clinical and clinical data.  Such data will include the 
              ***               Licensor shall also provide reasonable 
       technical assistance to facilitate an orderly transfer of the project, 
       provided that such assistance shall not be at a level that is unduly 
       burdensome to Licensor.  At the request of Licensee, Licensor may, in 
       its sole discretion, provide additional assistance at Licensee's 
       expense.  Promptly after the Effective Date, Licensor shall notify the 
       FDA that Licensee has acquired exclusive rights to Licensed Product, 
       and so should have access to relevant data relating to Licensed 
       Product on file at the FDA.

5.04   PERIODIC UPDATES - Licensee will update Licensor in writing not less 
       frequently than   ***       on the development status of the Licensed 
       compound.



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<PAGE>

                 VI.  PATENT MAINTENANCE/PATENT INFRINGEMENT

6.01   PATENT MAINTENANCE,  Licensor shall be responsible for prosecuting and 
       maintaining the Patent Rights.  In meeting such responsibility, 
       Licensor will rely on its staff attorneys to the same extent it 
       usually does in prosecuting similar patents and patent applications 
       owned by Licensor.

6.02   REIMBURSEMENT BY LICENSEE,  Licensee shall reimburse Licensor for all 
       costs incurred by Licensor in filing, prosecuting and maintaining the 
       Patent Rights during the term of this Agreement, except for those 
       costs relating to efforts of Licensor's staff attorneys.  In the event 
       that Licensee determines that it does not make commercial sense to 
       pursue filing, prosecuting and maintaining the Patent Rights in a 
       particular country and no longer desires to reimburse Licensor for 
       associated costs in such country, then Licensee shall so notify 
       Licensor, and Licensor may, in Licensor's discretion, maintain or 
       abandon the Patent Rights in that particular country.

6.03   NOTICE OF INFRINGEMENT,   Each party shall immediately give notice to 
       the other of any potential infringement or infringement by a third 
       party of any Patent Rights of which they become aware or of any 
       certification of which they become aware filed under the United States 
       "Drug Price Competition and Patent Term Restoration Act of 1984" 
       claiming that Patent Rights covering the Licensed Product are invalid 
       or unenforceable or that infringement will not arise from the 
       manufacture, use or sale of Licensed Product by a third party.

6.04   LICENSOR'S RIGHT TO BRING SUIT,  Licensor will have the right to 
       settle with the infringer or to bring suit or other proceeding at its 
       expense against the infringer in its own name

                                      -12-
<PAGE>

       or in the name of Licensee where necessary, after consultation with 
       Licensee.  Licensee shall be kept advised at all times of such suit or 
       proceedings brought by Licensor.  Licensee may, in its discretion, 
       join Licensor as party to the suit or other proceeding, provided that 
       Licensor shall retain control of the prosecution of such suit or 
       proceedings in such event.  Licensee agrees to cooperate with Licensor 
       in its efforts to protect Patent Rights, including joining as a party 
       where necessary. Licensor agrees to prosecute diligently any 
       litigation it initiates under this Section 6.04.

6.05   LICENSEE'S RIGHT TO BRING SUIT,  If within ninety (90) days after 
       receiving notice under Section 6.03 hereinabove, Licensor does not 
       settle with the infringer or bring suit or other proceeding against 
       the infringer, Licensee may in its discretion, bring suit or other 
       proceeding at its expense against the infringer, provided however, 
       that Licensee shall first consult with Licensor as to whether such 
       act(s) by a third party reasonably constitute infringement and whether 
       it is commercially advisable to bring such suit or proceeding, as 
       reasonably determined by Licensor.  Licensor shall be kept advised at 
       all times of such suit or proceedings brought by Licensee.  Licensor 
       may, in its discretion, join Licensor as party to the suit or other 
       proceeding, provided that Licensee shall retain control of the 
       prosecution of such suit or proceedings in such event.  Licensor 
       agrees to cooperate with Licensee in its efforts to protect Patent 
       Rights, including joining as a party where necessary.  Licensee agrees 
       to prosecute diligently any litigation it initiates under this Section 
       6.05.

6.06   LITIGATION EXPENSES,  Each party will bear its own expenses with 
       respect to any suit or other proceeding against an infringer.  Any 
       recovery in connection with such suit or proceeding will first be 
       applied to reimburse Licensee and Licensor for their out-of-pocket 
       expenses, including attorney's fees.  Any remaining recovery shall be 
       divided by the parties as follows: (i) if the damages awarded the 
       party controlling the suit include an amount based on          ***     
       then Licensor shall retain     ***     ***  and Licensee shall retain
                    ***             of said amount after first subtracting 
       from the award those amounts not based on         ***      
       (ii) if the damages awarded the party controlling the suit include an 
       amount based on  ***           ***     then, Licensee shall retain 
               ***      and Licensor       ***      of the award after first


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                                      -13-
<PAGE>

       subtracting from the award those amounts not based on       ***    
            ***    (iii) if the damages awarded the party controlling the suit 
       includes an amount based           ***                  ***            
       then the parties will each retain           ***        of such amount 
       and (iv) if the damages awarded the party controlling the suit 
       includes an amount not contemplated by (i)-(iii) above, then the 
       parties will each retain      ***      of such amount.

                           VII.  NOTICES; PAYMENTS

7.01   NOTICES,  Any notice required or permitted to be given hereunder 
       shall, except where specifically provided otherwise, be given in 
       writing to the person listed below by personal delivery, registered or 
       certified mail, return receipt requested, NEXT DAY AIR, telegram, 
       telex, or telecopier, and the date upon which such notice is so 
       personally delivered (or if notice is given by registered or certified 
       mail, the date that is three (3) business days from sending, or if by 
       NEXT DAY AIR, telegram, or telex or telecopier, the date of receipt at 
       the designated address) shall be deemed to be the date of such notice, 
       irrespective of the date appearing thereon:

       The DuPont Merck Pharmaceutical Company           Avid Corporation
       DuPont Merck Plaza, Walnut Run                    1667 Davis Street
       974 Centre Road                                   Camden, NJ 08029
       Wilmington, DE 19805                              Attn: Executive VP
       Attn:  Vice President, Business Development


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                                      -14-
<PAGE>

7.02   PAYMENTS,  Payments made to Licensor under Article II shall be wire to

             Licensor's account as follows:

             Mellon Bank, N.A.
             Independence Center
             701 Market Street
             Philadelphia, PA 19016
                  ***        
                  ***            

                VIII.  INDEMNIFICATION; INSURANCE; WARRANTIES

8.01   INDEMNIFICATION BY LICENSEE - Licensee shall at all times during the 
       term of this Agreement and thereafter, indemnify, defend and hold 
       Licensor, its officers, employees, parent companies and Affiliates, 
       from and against any and all claim, loss, damage, liability, injury, 
       cost or expense, including without limitation expenses of litigation 
       and reasonable attorneys' fees, in connection with any claims made or 
       suits brought by third parties against Licensor relating to this 
       Agreement including, without limitation, those arising out of the 
       death of or injury to any person or persons or out of any damage to 
       property and resulting from the production, manufacture, sale, use, 
       lease, consumption or advertisement of Licensed Product and those 
       arising from the negligence, willful misconduct, or material breach of 
       this Agreement by Licensee, its Affiliates, subcontractors or agents.

8.02   PROCEDURE. - Should Licensor or any of its officers, agents, parent 
       companies, affiliates, or employees (the "Indemnitee") intend to claim 
       indemnification under this Article VIII, such Indemnitee shall 
       promptly notify the Licensee (the "Indemnitor") in writing of any 
       loss, claim, damage, liability or action in respect of which the 
       Indemnitee intends to claim such indemnification, and the Indemnitor 
       shall be entitled to assume the defense thereof with counsel selected 
       by the Indemnitor and approved by the


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                                      -15-
<PAGE>

       Indemnitee, such approval not to be unreasonably withheld, PROVIDED, 
       HOWEVER, that if representation of Indemnitee by such counsel first 
       selected by the Indemnitor would be inappropriate due to a conflict of 
       interest between such Indemnitee and any other party represented by 
       such counsel, then Indemnitor shall select other counsel for the 
       defense of Indemnitee, with the fees and expenses to be paid by the 
       Indemnitor, such other counsel to be approved by Indemnitee and such 
       approval not to be unreasonably withheld.  The indemnity agreement in 
       this Article VIII shall not apply to amounts paid in settlement of any 
       loss, claim damage, liability or action if such settlement is effected 
       without the consent of the Indemnitor, which consent shall not be 
       withheld unreasonably.  The failure to deliver notice to the 
       Indemnitor within a reasonable time after the commencement of any such 
       action, if prejudicial to its ability to defend such action, shall 
       relieve such Indemnitor of any liability to the Indemnitee under this 
       Article VIII, but the omission so to deliver notice to the Indemnitor 
       will not relieve it of any liability that it may have to any 
       Indemnitee otherwise than under this Article VIII.  The Indemnities 
       under this Article VIII, its employees and agents, shall cooperate 
       fully with the Indemnitor and its legal representatives in the 
       investigation of any action, claim or liability covered by this 
       indemnification.

8.03   INSURANCE. - Licensee shall use best efforts to obtain liability 
       insurance promptly after the Effective Date and in no event later than 
       thirty (30) days after the Effective Date.  Such liability insurance 
       shall protect Licensee and Licensor in regard to events covered by 
       Section 8.01, and the nature and extent of the insurance coverage 
       shall be commensurate with usual and customary industry practices.  
       Thereafter, for the term of this Agreement, upon the commencement of 
       production, sale, or transfer, whichever occurs first, of any Licensed 
       Product, Licensee shall obtain and carry in full force and effect 
       liability insurance which shall protect Licensee and Licensor in 
       regard to events covered by Section 8.01, the nature and extent of 
       which insurance coverage shall be commensurate with usual and 
       customary industry practices.  Licensee shall name Licensor as an 
       additional insured and provide Licensor a certificate of insurance 
       evidencing coverage.

                                      -16-
<PAGE>

8.04   WARRANTY. - Except as otherwise expressly set forth in this Agreement, 
       LICENSOR MAKES NO REPRESENTATIONS AND EXTENDS NO WARRANTIES OF ANY 
       KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO 
       WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND 
       VALIDITY OF PATENT RIGHTS' CLAIMS, ISSUED OR PENDING.

                            IX.  TERM; TERMINATION

9.01   TERM AND EXPIRATION. - This Agreement shall be effective as of the 
       Effective Date and unless terminated earlier pursuant to Section 9.02, 
       9.03 or 9.04 below, the terms of this Agreement shall continue in 
       effect on a                    ***                       
                                  ***                           

9.02   TERMINATION FOR BREACH - In the event of a material breach by either 
       Licensor or Licensee of any of the obligations contained in this 
       Agreement, the other party shall be entitled to terminate this 
       Agreement by notice in writing under Section 7.01 provided that such 
       notice shall specify the complained of breach or breaches.  If the 
       said breach or breaches are capable of remedy, the party committing 
       such breach or breaches shall be entitled to a period of     ***      
       from the delivery of such notice in which to remedy or to undertake to 
       remedy the same.  In the case the defaulting party shall fail to 
       remedy the breach or to undertake to remedy the breach to the 
       satisfaction of the injured party, the injured party shall have the 
       right                ***                           ***            
       Failure of a party to exercise its rights under this Section 9.02 
       shall not be construed as a waiver as to future breaches whether or 
       not they are similar.


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                                      -17-
<PAGE>

9.03   TERMINATION BY LICENSEE - Licensee may terminate this Agreement, with 
       respect to:

              ***

              ***

       Licensee will disclose to Licensor its reasons for any such 
       termination.

9.04   TERMINATION BY LICENSOR - Licensor shall have the further right to 
       terminate this Agreement      ***      on written notice to License if:

                   ***
                   ***
                   ***
                   ***

9.05   ON TERMINATION - Licensee shall, upon termination of this Agreement:

       (a)  Immediately cease manufacture, use, importation and sale of 
            License Product;

       (b)  return to Licensor all copies of documents containing 
            Confidential Data and any materials received from Licensor under 
            confidentiality concerning compound, except that Licensee may 
            retain one (1) copy in its legal files to meet its obligations 
            hereunder that continue after termination under this Agreement;

       (c)  make no further use of any kind of any and all technology or 
            Confidential Data disclosed hereunder by Licensor with respect to
            Licensed Product, except to the 

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                                      -18-
<PAGE>

            extent such information has become public knowledge other than 
            through fault of Licensee;

       (d)  transfer to Licensor all approved and pending NDAs for all 
            countries within the Territory.

9.06   SURVIVAL OF CERTAIN OBLIGATIONS - The obligations set forth in 
       Sections 8.01 and 8.02, and Article X, and any obligations otherwise 
       accrued hereunder as of the date of termination shall survive 
       termination of this Agreement.

9.07   PAID-UP LICENSE - For each country, upon expiration of Licensee's 
       obligation to pay royalties pursuant to Section 3.03, License shall 
       have a fully paid-up, nonexclusive license under any Know-How, to 
       make, have made, use and sell Licensed Product in that country.

                             X.  CONFIDENTIALITY

10.01  NONDISCLOSURE OBLIGATION. - The parties hereto entered into a 
       Confidential Disclosure Agreement ("CDA") on December 18, 1995.  The 
       parties hereby agree that this Article X shall supersede and take the 
       place of the CDA, and that all Confidential Information disclosed by 
       one party to another, whether in the past or in the future, shall be 
       governed by the terms and conditions of this Article X. Confidential 
       Information includes but is not limited to compounds, intermediates, 
       data, designs, methods and processes, know-how, marketing strategies, 
       product plans, plans for research, developmental or experimental work, 
       development tools, financial information, test and safety data, and 
       supplier lists and information relating to Licensed Product.  The 
       parties hereto agree that all Confidential Information shall be 
       maintained in confidence by the recipient and shall not be disclosed 
       by the recipient to any other natural person, or any corporation, 
       firm, partnership or other business entity, or any government or any 
       agency or political subdivision thereof, without the prior written 
       consent of the other party, except to the extent that such 
       Confidential Information:

                                      -19-
<PAGE>

       (a)  is known by recipient at the time of its receipt, and not through 
            a prior disclosure by the disclosing party, as documented by 
            business records;

       (b)  is properly in the public domain;

       (c)  is subsequently disclosed to the receiving party by a third party 
            who may lawfully do so and is not under an obligation of 
            confidentiality to the disclosing party;

       (d)  is developed by the receiving party independently of Proprietary 
            Information or other information received from the other party;

       (e)  is disclosed to governmental or other regulatory agencies in 
            order to obtain patents or to gain approval to conduct clinical 
            trials or to market Licensed Product, but such disclosure may be 
            only to the extent reasonably necessary to obtain patents or 
            authorizations;

       (f)  is necessary or useful to be disclosed to prospective investors, 
            Sublicensees, agents, consultants, Affiliates and/or other third 
            parties for the research and development, manufacturing, 
            marketing and or sale of Licensed Product (or for such parties to 
            determine their interest in performing such activities) in 
            accordance with this Agreement on the condition that such third 
            parties agree to be bound by the confidentiality obligations 
            contained in this Agreement, provided that the term of 
            confidentiality for such third parties shall be no less than ten 
            (10) years; or

       (g)  is required to be disclosed by law or court order, provided that 
            notice is promptly delivered to the other party in order to 
            provide an opportunity to challenge or limit the disclosure, 
            obligations.

                                      -20-
<PAGE>

10.02  USE OF CONFIDENTIAL INFORMATION.  Both parties agree that the 
       Confidential Information shall only be used in connection with the 
       parties' respective rights and obligations under this Agreement.

10.03  PUBLICATION.  During the term of this Agreement, Licensee and Licensor 
       each acknowledge the other party's interest in publishing its results 
       to obtain recognition within the scientific community and to advance 
       the state of scientific knowledge.  Each party also recognizes the 
       mutual interest in obtaining valid patent protection and in protecting 
       business interests and trade secret information, Consequently, each 
       party agrees not to disclose Confidential Information of the other 
       party in publications without the express written consent of the other 
       party.  In addition, the contributions of the parties to the research 
       shall be expressly noted in such publications or other public 
       disclosures by acknowledgment or co-authorship, whichever is 
       appropriate.

                              XI.  MISCELLANEOUS

11.01  MODIFICATIONS - The terms and conditions of this Agreement may not be 
       amended or modified, except in a writing signed by both parties.

11.02  WAIVER - No failure or delay of either party to exercise any rights or 
       remedies under this Agreement shall operate as a waiver thereof nor 
       shall any single, or partial exercise or any rights or remedies 
       preclude any further or other exercise of the same or any other rights 
       or remedies with respect to any circumstances to be construed as a 
       waiver thereof with respect to any other circumstances.

11.03  ASSIGNMENT - Licensee may not assign any of its rights or delegate any 
       of its duties pursuant to this Agreement without the prior written 
       consent of Licensor and any attempted assignment without such consent 
       shall be void.

                                      -21-
<PAGE>

11.04  SEVERABILITY - In the event that any provision of this Agreement is 
       held invalid or unenforceable in any circumstance by a court of 
       competent jurisdiction, the remainder of this Agreement, and 
       application of such provision in any other circumstances, shall not be 
       affected thereby.

11.05  HEADINGS - The headings of articles and sections of this Agreement are 
       for convenience of reference only and shall not affect the meaning or 
       interpretation of this Agreement in any way.

11.06  APPLICABLE LAW/JURISDICTION - This Agreement shall be governed by and 
       construed in accordance with the laws of the        ***        without 
       regard to its conflicts of laws principles.  Any litigation regarding 
       this Agreement or performance of obligations in connection therewith 
       shall be in the courts of the                 ***
                     ***

11.07  FORCE MAJEURE - Neither party shall be responsible for any loss or 
       damage resulting from any delay in performing or failure to perform 
       any provisions of this Agreement, so long as any such failure or delay 
       arises from fires, floods, storms, earthquakes, civil commotion's, 
       strikes or other differences with workers or unions, or from any delay 
       or failure in delivery when the supplies of either party or the 
       facilities of production, manufacture, transportation or distribution 
       which otherwise would be available to either party are impaired by 
       mechanical breakdown or by causes beyond its control or by the order, 
       requisition, request, or recommendation of any governmental agency or 
       acting governmental authority, or either party's compliance therewith, 
       or by governmental regulation.

11.08  ENTIRE AGREEMENT - This Agreement constitutes the entire agreement 
       between Licensor and Licensee with respect to the subject matter 
       hereof, and supersedes all proposals,


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                                      -22-
<PAGE>

       oral or written, purchase orders, confidentiality agreements, and all 
       other communications between the parties with respect to such subject 
       matter, subject to any moneys due under the purchase orders between 
       the parties as of the date hereof.

11.09  COUNTERPARTS - This Agreement may be executed in counterparts, and 
       when each party has signed and delivered at least one counterpart, 
       each counterpart shall be deemed an original, and, when taken together 
       with other signed counterparts, shall constitute one Agreement, which 
       shall be binding upon and effective as to both parties.

11.10  USE OF NAMES - This Agreement does not confer any right to use the 
       name, tradename, trademark or other designation of either party.

11.11  INDEPENDENT CONTRACTORS - At all times during the term of this 
       Agreement, each party shall act as an independent contractor and 
       neither the making of this Agreement nor the performance of any of the 
       provisions hereof shall be construed to make one party an agent, 
       employee or legal representative of another party for any purpose, nor 
       shall this Agreement be deemed to establish a joint venture or 
       partnership.

11.12  REPRESENTATIONS AND WARRANTIES - Each party represents and warrants to 
       the other that it has the full right and authority to enter into this 
       Agreement, and that it is not aware of any impediment which would 
       inhibit its ability to perform the terms and conditions imposed on it 
       by such Agreement.

11.13  PUBLICITY - Each party will provide the other with a copy of any draft 
       press release covering the subject matter of this Agreement at least 
       one business day before issuance and in the case of a press release 
       covering the initial announcement of this Agreement, at least three 
       (3) business days before issuance - unless in the opinion of counsel 
       such delay in the issuance of the press release would result in a 
       violation of the securities law or other applicable law.  Each party 
       will give due regard to comments, if any, made by the other party in 
       response to a draft release.  Neither party may use the

                                      -23-
<PAGE>

       name of the other party or the other party's divisions affiliates, 
       subsidiaries, or products to imply an endorsement, without the written 
       consent of such other party.

IN WITNESS WHEREOF, the parties intending to be bound have duly executed this 
Agreement in duplicate by their appropriate authorized representative.

THE DUPONT MERCK                       AVID CORPORATION
PHARMACEUTICAL COMPANY


/s/ illegible                          /s/ illegible            
-----------------------------          -----------------------------
By                                     By

President and CEO                      Executive Vice Pres      
-----------------------------          -----------------------------
Title                                  Title

December 18, 1996                      December 18, 1996        
-----------------------------          -----------------------------
Date                                   Date


                                      -24-
<PAGE>

                                      SCHEDULE A

DOCKET NO.:   DM-6566-E
TITLE:   Substituted Cyclic Carbonyls and Derivatives Thereof Useful as
         Retroviral Protease Inhibitors

-------------------------------------------------------------------------------
COUNTRY  APPLN NO.   APPLN DATE   STATUS   PATENT NO.  ISSUE DATE   EXPIRY DATE
-------------------------------------------------------------------------------
US       08/197,630   2/16/94    Allowed             
-------------------------------------------------------------------------------

                                     1 of 6
<PAGE>

                                   SCHEDULE A

DOCKET NO.:   DM-6566-B
TITLE:   Substituted Cyclic Carbonyls and Derivatives Thereof Useful as
         Retroviral Protease Inhibitors

FOREIGN FAMILY FOR DM-6566-E

-------------------------------------------------------------------------------
COUNTRY  APPLN NO.   APPLN DATE   STATUS   PATENT NO.  ISSUE DATE   EXPIRY DATE
-------------------------------------------------------------------------------
ASTL     94/061808    10/13/92   Pending             
-------------------------------------------------------------------------------
ATRA     unknown      10/13/92   Pending             
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BELG     unknown      10/13/92   Pending             
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BRAZ     PI9206623-2  10/13/92   Pending             
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CANA     2120925      10/13/92   Pending             
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CZEC     PV00814-94   10/13/92   Pending             
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DENM     unknown      10/13/92   Pending             
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EPC      92922262.8   10/13/92   Pending             
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FINL     94/001649    10/13/92   Pending             
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FRAN     unknown      10/13/92   Pending             
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GBRI     unknown      10/13/92   Pending             
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GERM     unknown      10/13/92   Pending             
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GREC     unknown      10/13/92   Pending             
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HUNG     P94/01020    10/13/92   Pending             
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IREL     unknown      10/13/92   Pending             
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ITAL     unknown      10/13/92   Pending             
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JAPA     93/507244    04/11/94   Pending             
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KORS     94/701169    10/13/92   Pending             
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LUXE     unknown      10/13/92   Pending             
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NETH     unknown      10/13/92   Pending             
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NORW     94/001278    10/13/92   Pending             
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PCT      US92/08749   10/13/92   (Pending)           
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RUSS     94/031126    10/13/92   Pending             
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SLVK     PV00407-94   10/13/92   Pending             
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SPAI     unknown      10/13/92   Pending             
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SWED     unknown      10/13/92   Pending             
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SWIT     unknown      10/13/92   Pending             
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                                     2 of 6
<PAGE>

                                   SCHEDULE A

DOCKET NO.:   DM-6681
TITLE:   Method of Treating Human Immunodeficiency Virus Infection Using a
         Cyclic Protease Inhibitor in Combination with a Reverse Transcriptase
         Inhibitor

-------------------------------------------------------------------------------
COUNTRY  APPLN NO.   APPLN DATE   STATUS   PATENT NO.  ISSUE DATE   EXPIRY DATE
-------------------------------------------------------------------------------
US       08/110,603    8/26/93   Allowed             
-------------------------------------------------------------------------------


                                     3 of 6
<PAGE>

                                   SCHEDULE A

DOCKET NO.:   DM-6663
TITLE:   Improved Pharmaceutical Formulations of Cyclic Urea Type Compounds

-------------------------------------------------------------------------------
COUNTRY  APPLN NO.   APPLN DATE   STATUS   PATENT NO.  ISSUE DATE   EXPIRY DATE
-------------------------------------------------------------------------------
US       08/208,243    3/9/94    Granted   5,559,110     9/24/96     3/9/2014
-------------------------------------------------------------------------------


                                     4 of 6
<PAGE>

                                   SCHEDULE A


DOCKET NO.:   DM-6751
TITLE:   Method for Preparing N,N'-Disubstituted Cyclic Ureas

-------------------------------------------------------------------------------
COUNTRY  APPLN NO.   APPLN DATE   STATUS   PATENT NO.  ISSUE DATE   EXPIRY DATE
-------------------------------------------------------------------------------
US       08/469409     6/6/95    Granted   5,532,356     7/2/96      6/6/2015
-------------------------------------------------------------------------------


                                     5 of 6
<PAGE>
                                   SCHEDULE A

DOCKET NO.:   ***
TITLE:           ***

FOREIGN FAMILY FOR    ***   

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                                     6 of 6
<PAGE>

                                   SCHEDULE B


                        DMP 450 DEVELOPMENT TIME LINE (1)



                                      ***
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