=========================================================================

                        AGREEMENT AND PLAN OF MERGER

                       DATED AS OF SEPTEMBER 21, 1999

                                   AMONG

                              MEDIMMUNE, INC.

                           MARLIN MERGER SUB INC.

                                    AND

                           U.S. BIOSCIENCE, INC.

  =========================================================================



                             Table of Contents

                                                                        Page

 ARTICLE I      THE MERGER . . . . . . . . . . . . . . . . . . . . . . .   2
      Section 1.1    The Merger  . . . . . . . . . . . . . . . . . . . .   2
      Section 1.2    Closing . . . . . . . . . . . . . . . . . . . . . .   2
      Section 1.3    Effective Time  . . . . . . . . . . . . . . . . . .   2
      Section 1.4    Certificate of Incorporation and Bylaws . . . . . .   2
      Section 1.5    Directors and Officers  . . . . . . . . . . . . . .   3
      Section 1.6    Effects of the Merger . . . . . . . . . . . . . . .   3

 ARTICLE II     EFFECT OF THE MERGER ON THE CAPITAL STOCK OF THE
                CONSTITUENT CORPORATIONS; EXCHANGE OF CERTIFICATES . . .   3
      Section 2.1    Effect on Capital Stock . . . . . . . . . . . . . .   3
      Section 2.2    Exchange of Certificates  . . . . . . . . . . . . .   5

 ARTICLE III    REPRESENTATIONS AND WARRANTIES . . . . . . . . . . . . .   9
      Section 3.1    Representations and Warranties of the Company . . .   9
      Section 3.2    Representations and Warranties of Parent and
                       Sub . . . . . . . . . . . . . . . . . . . . . . .  29

ARTICLE IV      COVENANTS RELATING TO CONDUCT OF BUSINESS  . . . . . . .  36
      Section 4.1    Conduct of Business . . . . . . . . . . . . . . . .  36
      Section 4.2    No Solicitation . . . . . . . . . . . . . . . . . .  41

 ARTICLE V      ADDITIONAL AGREEMENTS  . . . . . . . . . . . . . . . . .  44
      Section 5.1    Preparation of the Form S-4 and the Proxy
                       Statement; Stockholders Meeting . . . . . . . . .  44
      Section 5.2    Letters of the Company's Accountants  . . . . . . .  45
      Section 5.3    Letters of Parent's Accountants . . . . . . . . . .  46
      Section 5.4    Access to Information; Confidentiality  . . . . . .  46
      Section 5.5    Reasonable Best Efforts . . . . . . . . . . . . . .  47
      Section 5.6    Stock Options . . . . . . . . . . . . . . . . . . .  48
      Section 5.7    Indemnification, Exculpation and Insurance  . . . .  50
      Section 5.8    Fees and Expenses . . . . . . . . . . . . . . . . .  50
      Section 5.9    Public Announcements  . . . . . . . . . . . . . . .  51
      Section 5.10   Affiliates  . . . . . . . . . . . . . . . . . . . .  52
      Section 5.11   Stock Exchange Listing  . . . . . . . . . . . . . .  52
      Section 5.12   Pooling of Interests  . . . . . . . . . . . . . . .  53
      Section 5.13   Tax Treatment . . . . . . . . . . . . . . . . . . .  53
      Section 5.14   Stockholder Litigation  . . . . . . . . . . . . . .  53
      Section 5.15   Rights Agreement  . . . . . . . . . . . . . . . . .  53
      Section 5.16   Conveyance Taxes  . . . . . . . . . . . . . . . . .  53

 ARTICLE VI     CONDITIONS PRECEDENT . . . . . . . . . . . . . . . . . .  54
      Section 6.1    Conditions to Each Party's Obligation to
                       Effect the Merger . . . . . . . . . . . . . . . .  54
      Section 6.2    Conditions to Obligations of Parent and Sub . . . .  55
      Section 6.3    Conditions to Obligation of the Company . . . . . .  56
      Section 6.4    Frustration of Closing Conditions . . . . . . . . .  57

 ARTICLE VII    TERMINATION, AMENDMENT AND WAIVER  . . . . . . . . . . .  57
      Section 7.1    Termination . . . . . . . . . . . . . . . . . . . .  57
      Section 7.2    Effect of Termination . . . . . . . . . . . . . . .  58
      Section 7.3    Amendment . . . . . . . . . . . . . . . . . . . . .  59
      Section 7.4    Extension; Waiver.  . . . . . . . . . . . . . . . .  59

 ARTICLE VIII   GENERAL PROVISIONS . . . . . . . . . . . . . . . . . . .  59
      Section 8.1    Nonsurvival of Representations and Warranties . . .  59
      Section 8.2    Notices . . . . . . . . . . . . . . . . . . . . . .  59
      Section 8.3    Definitions . . . . . . . . . . . . . . . . . . . .  61
      Section 8.4    Interpretation  . . . . . . . . . . . . . . . . . .  62
      Section 8.5    Counterparts  . . . . . . . . . . . . . . . . . . .  63
      Section 8.6    Entire Agreement; Third-Party Beneficiaries . . . .  63
      Section 8.7    Governing Law . . . . . . . . . . . . . . . . . . .  63
      Section 8.8    Assignment  . . . . . . . . . . . . . . . . . . . .  63
      Section 8.9    Enforcement . . . . . . . . . . . . . . . . . . . .  63
      Section 8.10   Severability  . . . . . . . . . . . . . . . . . . .  64


 Exhibit A Form of Company Affiliate Letter
 Exhibit B Form of Parent Affiliate Letter



      AGREEMENT AND PLAN OF MERGER (this "Agreement"), dated as of September
 21, 1999, among MedImmune, Inc., a Delaware corporation ("Parent"), Marlin
 Merger Sub Inc., a Delaware corporation and a newly formed, direct, wholly
 owned subsidiary of Parent ("Sub"), and U.S. Bioscience, Inc., a Delaware
 corporation (the "Company").

      WHEREAS, the respective Boards of Directors of Parent, Sub and the
 Company have approved and declared advisable this Agreement and the merger
 of Sub with and into the Company (the "Merger"), upon the terms and subject
 to the conditions set forth in this Agreement, whereby each issued and
 outstanding share of common stock, par value $0.01 per share, of the
 Company ("Company Common Stock"), other than Company Common Stock owned by
 Parent, Sub or the Company, will be converted into the right to receive
 common stock, par value $0.01 per share, of Parent ("Parent Common Stock")
 as set forth herein;

      WHEREAS, in order to induce Parent to execute and deliver this
 Agreement, Parent and the Company are entering into a stock option
 agreement (the "Option Agreement"), pursuant to which the Company is
 granting Parent the option to purchase shares of Company Common Stock, upon
 the terms and subject to the conditions set forth therein;

      WHEREAS, for U.S. Federal income tax purposes, it is intended that the
 Merger shall qualify as a reorganization within the meaning of Section
 368(a) of the Internal Revenue Code of 1986, as amended (the "Code"), and
 that this Agreement shall be, and is hereby, adopted as a plan of
 reorganization for purposes of Section 368 of the Code; and

      WHEREAS, for financial accounting purposes, it is intended that the
 Merger will be accounted for as a pooling of interests transaction under
 generally accepted accounting principles ("GAAP").

            NOW, THEREFORE, in consideration of the representations,
 warranties, covenants and agreements contained in this Agreement and
 intending to be legally bound hereby, the parties hereto agree as follows:


                                  ARTICLE I
                                 THE MERGER

      Section 1.1    The Merger.  Upon the terms and subject to the
 conditions set forth in this Agreement, and in accordance with the Delaware
 General Corporation Law (the "DGCL"), Sub shall be merged with and into the
 Company at the Effective Time.  Following the Effective Time, the separate
 corporate existence of Sub shall cease and the Company shall continue as
 the surviving corporation (the "Surviving Corporation") and shall succeed
 to and assume all the rights and obligations of Sub in accordance with the
 DGCL.

      Section 1.2    Closing.  The closing of the Merger (the "Closing")
 will take place at 10:00 a.m. on a date to be specified by the parties (the
 "Closing Date"), which shall be no later than the second Business Day after
 satisfaction or waiver of the conditions set forth in ARTICLE VI (other
 than those conditions that by their nature are to be satisfied at the
 Closing, but subject to the satisfaction or waiver of those conditions), at
 the offices of Dewey Ballantine LLP, 1301 Avenue of the Americas, New York,
 New York 10019, unless another date or place is agreed to by the parties
 hereto.

      Section 1.3    Effective Time.  Subject to the provisions of this
 Agreement, as soon as practicable on the Closing Date, the parties shall
 file a certificate of merger (the "Certificate of Merger") executed in
 accordance with the relevant provisions of the DGCL and shall make all
 other filings or recordings required under the DGCL.  The Merger shall
 become effective at such time as the Certificate of Merger is duly filed
 with the Secretary of State of the State of Delaware, or at such other time
 as Parent and the Company shall agree and specify in the Certificate of
 Merger (the time the Merger becomes effective being the "Effective Time").

      Section 1.4    Certificate of Incorporation and Bylaws.

            (a)     The Certificate of Incorporation of Sub, as in effect
 immediately prior to the Effective Time, shall be the Certificate of
 Incorporation of the Surviving Corporation until thereafter amended as
 provided therein or by applicable law, provided that the name of the
 Surviving Corporation shall be changed to the name of the Company.

            (b)     The Bylaws of Sub, as in effect immediately prior to
 the Effective Time, shall be the Bylaws of the Surviving Corporation until
 thereafter amended as provided therein or by applicable law.

      Section 1.5    Directors and Officers.

            (a)     The directors of Sub immediately prior to the Effective
 Time shall be the directors of the Surviving Corporation, until the earlier
 of their resignation or removal or until their respective successors are
 duly elected and qualified, as the case may be.

            (b)     The officers of the Company immediately prior to the
 Effective Time shall be the officers of the Surviving Corporation, until
 the earlier of their resignation or removal or until their respective
 successors are duly elected and qualified, as the case may be.

      Section 1.6    Effects of the Merger.  The Merger shall have the
 effects set forth in Section 259 of the DGCL.


                                 ARTICLE II
              EFFECT OF THE MERGER ON THE CAPITAL STOCK OF THE
             CONSTITUENT CORPORATIONS; EXCHANGE OF CERTIFICATES

      Section 2.1    Effect on Capital Stock.  As of the Effective Time, by
 virtue of the Merger and without any action on the part of the holder of
 any shares of Company Common Stock or any shares of capital stock of Sub:

            (a)     Capital Stock of Sub.  Each issued and outstanding
 share of capital stock of Sub shall be converted into and become one
 validly issued, fully paid and nonassessable share of common stock, par
 value $.01 per share, of the Surviving Corporation.

            (b)     Cancellation of Treasury Stock and Parent-Owned Stock.
 Each share of Company Common Stock that is owned by the Company, Parent or
 Sub shall automatically be canceled and retired and shall cease to exist,
 and no Parent Common Stock or other consideration shall be delivered in
 exchange therefor.

            (c)     Conversion of Company Common Stock.  Subject to Section
 2.2(e), each issued and outstanding share of Company Common Stock (other
 than shares to be canceled in accordance with Section 2.1(b)) shall be
 converted into the right to receive a number of validly issued, fully paid
 and nonassessable shares of Parent Common Stock equal to the Exchange Ratio
 (the "Merger Consideration").  As of the Effective Time, all such shares of
 Company Common Stock shall no longer be outstanding and shall automatically
 be canceled and retired and shall cease to exist, and each holder of a
 certificate which immediately prior to the Effective Time represented any
 such shares of Company Common Stock shall cease to have any rights with
 respect thereto, except the right to receive the Merger Consideration and
 any cash in lieu of fractional shares of Parent Common Stock to be issued
 or paid in consideration therefor upon surrender of such certificate in
 accordance with Section 2.2, without interest.  Notwithstanding the
 foregoing, if between the date of this Agreement and the Effective Time the
 outstanding shares of Parent Common Stock shall have been changed into a
 different number of shares or a different class, by reason of the
 occurrence or record date of any stock dividend, subdivision,
 reclassification, recapitalization, split, combination, exchange of shares
 or similar transaction, the Merger Consideration shall be appropriately
 adjusted to reflect such stock dividend, subdivision, reclassification,
 recapitalization, split, combination, exchange or similar transaction.

            (d)     The "Exchange Ratio" shall be 0.1500, provided that, if
 the Parent Share Price shall be (i) greater than $140, the Exchange Ratio
 shall be $19.10 divided by the Parent Share Price, (ii) $140 or lower but
 more than $132, the Exchange Ratio shall be 0.1364, (iii) $132 or lower but
 more than $120, the Exchange Ratio shall be $18 divided by the Parent Share
 Price, (iv) $100 or lower but more than $88, the Exchange Ratio shall be
 $15 divided by the Parent Share Price, (v) $88 or lower, the Exchange Ratio
 shall be 0.1705 (except as provided in paragraph (e) below).  The Exchange
 Ratio shall be rounded to the nearest 1/10,000th of a share.  "Parent Share
 Price" shall be the average of the closing prices of the shares of Parent
 Common Stock on the Nasdaq National Market for the 20 consecutive trading
 days ending on the third trading day prior to the date of the Stockholders
 Meeting, as reported by The Wall Street Journal (or, if not reported
 thereby, any other authoritative source), provided, that the last five
 trading days of 1999 and the first two trading days of 2000 shall not be
 considered trading days for purposes of this sentence.

            (e)     If the Parent Share Price shall be less than $80, the
 Company may, no later than 12:00 noon New York City time, on the second
 trading day prior to the date of the Stockholders Meeting, deliver a notice
 to Parent to the effect that the Company is terminating this Agreement
 pursuant to Section 2.1(e).  Such termination shall be effective at 10:00
 a.m. New York City time on the trading day following Parent's receipt of
 such notice, unless Parent shall, prior to such time, deliver a notice (the
 "Top-Up Notice") to the effect that the Exchange Ratio shall be $13.64
 divided by the Parent Share Price.

      Section 2.2    Exchange of Certificates.

            (a)     Exchange Agent.  As of the Effective Time, Parent shall
 deposit with American Stock Transfer and Trust Company of New York or such
 other bank or trust company as may be designated by Parent (the "Exchange
 Agent") and which shall be reasonably acceptable to the Company, for the
 benefit of the holders of shares of Company Common Stock, for exchange in
 accordance with this ARTICLE II, through the Exchange Agent, certificates
 representing the shares of Parent Common Stock (such shares of Parent
 Common Stock, together with any dividends or distributions with respect
 thereto with a record date after the Effective Time and any cash payments
 in lieu of any fractional shares of Parent Common Stock, being hereinafter
 referred to as the "Exchange Fund") issuable pursuant to Section 2.1 in
 exchange for outstanding shares of Company Common Stock.

            (b)     Exchange Procedures.  As soon as reasonably practicable
 after the Effective Time, Parent shall cause the Exchange Agent to mail to
 each holder of record of a certificate or certificates which immediately
 prior to the Effective Time represented outstanding shares of Company
 Common Stock (the "Certificates") whose shares were converted into the
 right to receive the Merger Consideration pursuant to Section 2.1(c), (i) a
 letter of transmittal (which shall specify that delivery shall be effected,
 and risk of loss and title to the Certificates shall pass, only upon
 delivery of the Certificates to the Exchange Agent and shall be in such
 form and have such other provisions as Parent may reasonably specify) and
 (ii) instructions for use in surrendering the Certificates in exchange for
 certificates representing the Merger Consideration.  Upon surrender of a
 Certificate for cancellation to the Exchange Agent, together with such
 letter of transmittal, duly executed, and such other documents as may
 reasonably be required by the Exchange Agent, the holder of such
 Certificate shall be entitled to receive in exchange therefor (x) a
 certificate representing that number of whole shares of Parent Common Stock
 which such holder has the right to receive pursuant to the provisions of
 this ARTICLE II after taking into account all the shares of Company Common
 Stock then held by such holder under all such Certificates so surrendered,
 (y) cash in lieu of fractional shares of Parent Common Stock to which such
 holder is entitled pursuant to Section 2.2(e), and (z) any dividends or
 other distributions to which such holder is entitled pursuant to Section
 2.2(c) (in each case, after giving effect to any required withholding
 taxes), and the Certificate so surrendered shall forthwith be canceled.  In
 the event of a transfer of ownership of Company Common Stock which is not
 registered in the transfer records of the Company, a certificate
 representing the proper number of shares of Parent Common Stock may be
 issued to a Person other than the Person in whose name the Certificate so
 surrendered is registered, if, upon presentation to the Exchange Agent,
 such Certificate shall be properly endorsed or otherwise be in proper form
 for transfer and the Person requesting such issuance shall pay any transfer
 or other taxes required by reason of the issuance of shares of Parent
 Common Stock to a Person other than the registered holder of such
 Certificate or establish to the reasonable satisfaction of Parent that such
 tax has been paid or is not applicable.  Notwithstanding anything to the
 contrary contained herein, no certificate representing Parent Common Stock
 or cash in lieu of a fractional share interest shall be delivered to a
 person who is a "affiliate" (as contemplated by Section 5.10(a) hereof) of
 the Company unless such affiliate has theretofore executed and delivered to
 Parent the agreement referred to in Section 5.10(a).  Until surrendered as
 contemplated by this Section 2.2(b), each Certificate shall be deemed at
 any time after the Effective Time to represent only the right to receive
 upon such surrender the Merger Consideration, cash in lieu of any
 fractional shares of Parent Common Stock as contemplated by Section 2.2(e)
 and any dividends or other distributions to which such holder is entitled
 pursuant to Section 2.2(c).  No interest will be paid or will accrue on any
 cash payable to holders of Certificates pursuant to Section 2.1(c) or
 Section 2.2(e).

            (c)     Distributions with Respect to Unexchanged Shares.  No
 dividends or other distributions with respect to Parent Common Stock with a
 record date after the Effective Time shall be paid to the holder of any
 unsurrendered Certificate with respect to the shares of Parent Common Stock
 represented thereby, and no cash payment in lieu of fractional shares shall
 be paid to any such holder pursuant to Section 2.2(e) until the holder of
 record of such Certificate shall surrender such Certificate in accordance
 with this ARTICLE II.  Subject to the effect of applicable escheat or
 similar laws, following surrender of any such Certificate, there shall be
 paid to the record holder of the certificate representing whole shares of
 Parent Common Stock issued in exchange therefor, without interest, (i) at
 the time of such surrender, the amount of any cash payable in lieu of a
 fractional share of Parent Common Stock to which such holder is entitled
 pursuant to Section 2.2(e) and the amount of dividends or other
 distributions with a record date after the Effective Time theretofore paid
 with respect to such whole shares of Parent Common Stock, less the amount
 of any withholding taxes which may be required thereon, and (ii) at the
 appropriate payment date, the amount of dividends or other distributions
 with a record date after the Effective Time but prior to such surrender and
 a payment date subsequent to such surrender payable with respect to such
 whole shares of Parent Common Stock, less the amount of any withholding
 taxes which may be required thereon.

            (d)     No Further Ownership Rights in Company Common Stock.
 All shares of Parent Common Stock issued upon the surrender for exchange of
 Certificates in accordance with the terms of this ARTICLE II (including any
 cash paid pursuant to Section 2.2(c) or Section 2.2(e)) shall be deemed to
 have been issued (and paid) in full satisfaction of all rights pertaining
 to the shares of Company Common Stock previously represented by such
 Certificates, subject, however, to the Surviving Corporation's obligation
 to pay any dividends or make any other distributions with a record date
 prior to the Effective Time which may have been declared or made by the
 Company on such shares of Company Common Stock in accordance with the terms
 of this Agreement or prior to the date of this Agreement and which remain
 unpaid at the Effective Time, and there shall be no further registration of
 transfers on the stock transfer books of the Surviving Corporation of the
 shares of Company Common Stock which were outstanding immediately prior to
 the Effective Time.  If, after the Effective Time, Certificates are
 presented to the Surviving Corporation or the Exchange Agent for any
 reason, they shall be canceled and exchanged as provided in this ARTICLE
 II.
            (e)     No Fractional Shares.

                (i)  No certificates or scrip representing fractional shares
      of Parent Common Stock shall be issued upon the surrender for exchange
      of Certificates, no dividend or distribution of Parent shall relate to
      such fractional share interests and such fractional share interests
      will not entitle the owner thereof to vote or to any rights of a
      stockholder of Parent.

                (ii)  Notwithstanding any other provision of this Agreement,
      each holder of shares of Company Common Stock exchanged pursuant to
      the Merger who would otherwise have been entitled to receive a
      fraction of a share of Parent Common Stock (after taking into account
      all Certificates delivered by such holder) shall receive, in lieu
      thereof, cash (without interest) in an amount, less the amount of any
      withholding taxes which may be required thereon, equal to such
      fractional part of a share of Parent Common Stock multiplied by the
      per share closing price of Parent Common Stock on the Nasdaq National
      Market on the Closing Date, as such price is reported by The Wall
      Street Journal (or, if not reported thereby, any other authoritative
      source).

            (f)     Termination of Exchange Fund.  Any portion of the
 Exchange Fund which remains undistributed to the holders of the
 Certificates for six months after the Effective Time shall be delivered to
 Parent, upon demand, and any holders of the Certificates who have not
 theretofore complied with this ARTICLE II shall thereafter look only to
 Parent for, and Parent shall remain liable for, payment of their claim for
 Merger Consideration, any cash in lieu of fractional shares of Parent
 Common Stock and any dividends or distributions with respect to Parent
 Common Stock.

            (g)     No Liability.  None of Parent, Sub, the Company or the
 Exchange Agent shall be liable to any Person in respect of any shares of
 Parent Common Stock (or dividends or distributions with respect thereto) or
 cash in lieu of fractional shares of Parent Common Stock or cash from the
 Exchange Fund, in each case delivered to a public official pursuant to any
 applicable abandoned property, escheat or similar law.

            (h)     Investment of Exchange Fund.  The Exchange Agent shall
 invest any cash included in the Exchange Fund, as directed by Parent, on a
 daily basis.  Any interest and other income resulting from such investments
 shall be paid to Parent.

            (i)     Lost Certificates.  If any Certificate shall have been
 lost, stolen or destroyed, upon the making of an affidavit of that fact by
 the Person claiming such Certificate to be lost, stolen or destroyed and,
 if required by the Surviving Corporation, the posting by such Person of a
 bond in such reasonable amount as the Surviving Corporation may direct as
 indemnity against any claim that may be made against it with respect to
 such Certificate, the Exchange Agent will issue in exchange for such lost,
 stolen or destroyed Certificate the Merger Consideration and any cash in
 lieu of fractional shares, and unpaid dividends and distributions on shares
 of Parent Common Stock deliverable in respect thereof, in each case
 pursuant to this Agreement.


                                 ARTICLE III
                       REPRESENTATIONS AND WARRANTIES

      Section 3.1    Representations and Warranties of the Company.  Except
 as set forth on the disclosure schedule delivered by the Company to Parent
 prior to the execution of this Agreement, which disclosure schedule
 specifies the section or subsection of this Agreement to which the
 exception relates (the "Company Disclosure Schedule"), the Company
 represents and warrants to Parent and Sub as follows:

            (a)     Organization, Standing and Corporate Power.  Each of
 the Company and its operating Subsidiaries listed in Section 3.1(a) of the
 Company Disclosure Schedule (the "Operating Subsidiaries") is a corporation
 duly organized, validly existing and, to the extent applicable, in good
 standing under the laws of the jurisdiction in which it is organized and
 has all requisite corporate power and authority to carry on its business as
 now being conducted.  Each of the Company and its Operating Subsidiaries is
 duly qualified or licensed to do business and, to the extent applicable, is
 in good standing in each jurisdiction in which the nature of its business
 or the ownership, leasing or operation of its properties makes such
 qualification or licensing necessary, other than in such jurisdictions
 where the failure to be so qualified or licensed individually or in the
 aggregate would not have a Material Adverse Effect on the Company.  The
 Company has made available to Parent prior to the execution of this
 Agreement complete and correct copies of its Restated Certificate of
 Incorporation, as amended (the "Company Certificate of Incorporation") and
 Bylaws (the "Bylaws"), and the comparable organizational documents of each
 of its Operating Subsidiaries, in each case as amended to the date hereof.

            (b)     Subsidiaries.  Exhibit 22 to the Company's Annual
 Report on Form 10-K for the fiscal year ended December 31, 1998 lists all
 the Subsidiaries of the Company.  All the outstanding shares of capital
 stock of, or other equity interests in, each such Subsidiary have been
 validly issued and are fully paid and nonassessable and are owned directly
 or indirectly by the Company free and clear of all Liens, and free of any
 restriction on the right to vote, sell or otherwise dispose of such capital
 stock or other ownership interests.  Other than such Subsidiaries of the
 Company, neither the Company nor any Subsidiary owns any equity interest in
 any person.

            (c)     Capital Structure.  The authorized capital stock of the
 Company consists of 50,000,000 shares of Company Common Stock and 5,000,000
 shares of preferred stock, par value $.005 per share ("Preferred Stock").
 At the close of business on September 17, 1999, (i) 27,516,867 shares of
 Company Common Stock were issued and outstanding, (ii) 23,906 shares of
 Company Common Stock were held by the Company in its treasury, (iii)
 8,174,977 shares of Company Common Stock were issuable pursuant to
 outstanding Company Stock Options, (iv) no shares of Preferred Stock were
 issued or outstanding, (v) 500,000 shares of Series A Preferred Stock were
 reserved for issuance in connection with the Rights issued pursuant to the
 Rights Agreement and (vi) 537,346 shares of Company Common Stock were
 issuable under the Warrants for the purchase of 472,293, 53,735 and 11,318
 shares, respectively, of the Company's common stock, granted to Domain
 Partners IV, L.P., Proquest Investments L.P. and DP IV Associates, L.P.,
 respectively, on February 2, 1999.  Except as set forth above in this
 Section 3.1(c) at the close of business on September 17, 1999, no shares of
 capital stock or other voting securities of the Company were issued,
 issuable, reserved for issuance or outstanding.  Except as set forth above
 in this Section 3.1(c) and pursuant to the Option Agreement, there are no
 outstanding stock appreciation rights or rights to receive shares of
 Company Common Stock on a deferred basis granted under the Company Stock
 Plans or otherwise.  All outstanding shares of capital stock of the Company
 are, and all shares which may be issued pursuant to the Company Stock Plans
 will be, when issued in accordance with the terms thereof, duly authorized,
 validly issued, fully paid and nonassessable and not subject to preemptive
 rights.  Except as set forth above in this Section 3.1(c), there are no
 bonds, debentures, notes or other indebtedness of the Company having the
 right to vote (or convertible into, or exchangeable for, securities having
 the right to vote) on any matters on which stockholders of the Company may
 vote.  Section 3.1(c) of the Company Disclosure Schedule lists each
 outstanding Stock Option and the holder thereof, the number of shares
 issuable thereunder and the grant date, exercise price and expiration date
 thereof.  Except as set forth above in this Section 3.1(c) or resulting
 from the issuance of shares of Company Common Stock pursuant to Stock
 Options outstanding as of the close of business on September 17, 1999 or
 the Option Agreement, (x) there are not issued, issuable, reserved for
 issuance or outstanding (A) any shares of capital stock or other voting
 securities of the Company, (B) any securities of the Company convertible
 into or exchangeable or exercisable for shares of capital stock or voting
 securities of the Company, (C) any warrants, calls, options or other rights
 to acquire from the Company or any Company Subsidiary, and no obligation of
 the Company or any Company Subsidiary to issue, any capital stock, voting
 securities or securities convertible into or exchangeable or exercisable
 for capital stock or voting securities of the Company and (y) there are not
 any outstanding obligations of the Company or any Company Subsidiary to
 repurchase, redeem or otherwise acquire any such securities or to issue,
 deliver or sell, or cause to be issued, delivered or sold, any such
 securities.  Neither the Company nor any Subsidiary is a party to any
 voting agreement with respect to the voting of any such securities.  Except
 as set forth in this Section 3.1(c), there are no issued, issuable,
 reserved for issuance or outstanding (A) securities of the Company or any
 Company Subsidiary convertible into or exchangeable or exercisable for
 shares of capital stock or other voting securities or ownership interests
 in any Company Subsidiary, (B) warrants, calls, options or other rights to
 acquire from the Company or any Company Subsidiary, and no obligation of
 the Company or any Company Subsidiary to issue, any capital stock, voting
 securities or other ownership interests in, or any securities convertible
 into or exchangeable or exercisable for any capital stock, voting
 securities or ownership interests in, any Company Subsidiary or (C)
 obligations of the Company or any Company Subsidiary to repurchase, redeem
 or otherwise acquire any such outstanding securities of Company
 Subsidiaries or to issue, deliver or sell, or cause to be issued, delivered
 or sold, any such securities.  Except as set forth above in this Section
 3.1(c), neither the Company nor any Subsidiary is a party to or bound by
 any agreement regarding any securities of the Company or any Subsidiary.

            (d)     Authority; Noncontravention.  The Company has the
 requisite corporate power and authority to enter into this Agreement and to
 consummate the transactions contemplated by this Agreement.  The Company
 has all requisite corporate power and authority to enter into the Option
 Agreement and to consummate the transactions contemplated thereby.  The
 execution and delivery of this Agreement and the Option Agreement by the
 Company and the consummation by the Company of the transactions
 contemplated by this Agreement and the Option Agreement have been duly
 authorized by all necessary corporate action on the part of the Company and
 no other corporate proceedings on the part of the Company are necessary to
 authorize this Agreement or the Option Agreement or to consummate the
 transactions contemplated hereby and thereby, subject, in the case of the
 Merger, to receipt of the Stockholder Approval and the filing of the
 Certificate of Merger.  The Board of Directors of the Company has
 unanimously approved this Agreement, determined that this Agreement and the
 transactions contemplated hereby are fair to and in the best interests of
 the Company and its stockholders and declared that the Merger is advisable.
 This Agreement and the Option Agreement have been duly executed and
 delivered by the Company and, assuming the due authorization, execution and
 delivery by each of the other parties thereto, constitute legal, valid and
 binding obligations of the Company, enforceable against the Company in
 accordance with their terms (except insofar as enforceability may be
 limited by applicable bankruptcy, insolvency, reorganization, moratorium or
 other similar laws affecting creditors' rights generally or by principles
 governing availability of equitable remedies).

            The execution and delivery of this Agreement and the Option
 Agreement do not, and the consummation of the Merger and the other
 transactions contemplated by this Agreement and the Option Agreement and
 compliance with the provisions of this Agreement and the Option Agreement
 will not, conflict with, or result in any violation of, or default (with or
 without notice or lapse of time, or both) under, or give rise to a right of
 termination, cancellation or acceleration of any obligation or to loss of a
 benefit under, or result in the creation of any pledge, claim, lien,
 charge, encumbrance or security interest of any kind or nature whatsoever
 (collectively, "Liens") in or upon any of the properties or assets of the
 Company or any Subsidiary under, (i) the Company Certificate of
 Incorporation or Bylaws or the comparable organizational documents of any
 of its Subsidiaries, (ii) any loan or credit agreement, bond, note,
 mortgage, indenture, lease or other contract, agreement, obligation,
 commitment, arrangement, understanding, instrument, permit or license
 applicable to the Company or any of its Subsidiaries or their respective
 properties or assets or (iii) subject to the governmental filings and other
 matters referred to in the following paragraph, any (A) statute, law,
 ordinance, rule or regulation or (B) judgment, order or decree, in each
 case applicable to the Company or any of its Subsidiaries or their
 respective properties or assets, other than, in the case of clauses (ii)
 and (iii), any such conflicts, violations, defaults, rights or Liens that
 individually or in the aggregate would not have a Material Adverse Effect
 on the Company.

            No consent, approval, order or authorization of, action by or
 in respect of, or registration, declaration or filing with, any Federal,
 state, local or foreign government, any court, administrative, regulatory
 or other governmental agency, commission or authority or any non-
 governmental self-regulatory agency, commission or authority (each, a
 "Governmental Entity") is required by or with respect to the Company or any
 of its Subsidiaries in connection with the execution and delivery of this
 Agreement or the Option Agreement by the Company or the consummation by the
 Company of the Merger or the other transactions contemplated by this
 Agreement or the Option Agreement, except for (1) the filing of a premerger
 notification and report form by the Company under the Hart-Scott-Rodino
 Antitrust Improvements Act of 1976, as amended (the "HSR Act"), and any
 applicable filings and approvals under similar foreign antitrust laws and
 regulations, (2) the filing with the Securities and Exchange Commission
 (the "SEC") of (A) a proxy statement relating to the adoption by the
 Company's stockholders of this Agreement (as amended or supplemented from
 time to time, the "Proxy Statement") and (B) such reports under Section
 13(a), 13(d), 15(d) or 16(a) of the Securities Exchange Act of 1934 (the
 "Exchange Act"), as may be required in connection with this Agreement, the
 Option Agreement and the transactions contemplated by this Agreement or the
 Option Agreement, (3) the filing of the Certificate of Merger with the
 Secretary of State of the State of Delaware, (4) such filings with and
 approvals of the American Stock Exchange ("AMEX") to permit the shares of
 Company Common Stock that are to be issued pursuant to the Option Agreement
 to be traded on AMEX and (5) such other consents, approvals, orders,
 authorizations, registrations, declarations and filings the failure of
 which to be obtained or made individually or in the aggregate would not
 have a Material Adverse Effect on the Company.

            (e)     SEC Documents.  The Company has timely filed all
 reports, schedules, forms, statements and other documents (including
 exhibits and other information incorporated therein) with the SEC required
 to be filed by the Company since January 1, 1998 (the "SEC Documents").  As
 of their respective dates, the SEC Documents complied in all material
 respects with the requirements of the Securities Act of 1933 (the
 "Securities Act"), or the Exchange Act, as the case may be, and the rules
 and regulations of the SEC promulgated thereunder applicable to such SEC
 Documents, and none of the SEC Documents contained any untrue statement of
 a material fact or omitted to state a material fact required to be stated
 therein or necessary in order to make the statements therein, in light of
 the circumstances under which they were made, not misleading.  Except to
 the extent that information contained in any SEC Document has been revised
 or superseded by a later-filed Filed SEC Document, none of the SEC
 Documents contains any untrue statement of a material fact or omits to
 state any material fact required to be stated therein or necessary in order
 to make the statements therein, in light of the circumstances under which
 they were made, not misleading.  The financial statements of the Company
 included in the SEC Documents comply in all material respects with
 applicable accounting requirements and the published rules and regulations
 of the SEC with respect thereto, have been prepared in accordance with
 GAAP, applied on a consistent basis during the periods involved (except as
 may be indicated in the notes thereto) and fairly present the financial
 position of the Company and its consolidated Subsidiaries as of the dates
 thereof and the consolidated results of their operations and cash flows for
 the periods then ended (subject, in the case of unaudited statements, to
 normal year-end audit adjustments not material in amount).  Except (i) as
 set forth in the Filed SEC Documents or (ii) for liabilities set forth in
 this Agreement or the Option Agreement, neither the Company nor any of its
 Subsidiaries has any liabilities or obligations of any nature (whether
 accrued, absolute, contingent or otherwise) which, individually or in the
 aggregate, would have a Material Adverse Effect on the Company.  For
 purposes of this Agreement, a "Filed SEC Document" shall mean an SEC
 Document filed by the Company and publicly available prior to the date of
 this Agreement.

            (f)     Information Supplied.  None of the information to be
 supplied by the Company specifically for inclusion or incorporation by
 reference in the registration statement on Form S-4 to be filed with the
 SEC by Parent in connection with the issuance of Parent Common Stock in the
 Merger (the "Form S-4") will, at the time the Form S-4 becomes effective
 under the Securities Act, contain any untrue statement of a material fact
 or omit to state any material fact required to be stated therein or
 necessary to make the statements therein, in light of the circumstances
 under which they are made, not misleading and the Proxy Statement will not,
 on the date it is first mailed to the Company's stockholders and at the
 time of the Stockholders Meeting, contain any untrue statement of a
 material fact or omit to state any material fact required to be stated
 therein or necessary in order to make the statements therein, in light of
 the circumstances under which they are made, not misleading.  The Proxy
 Statement will comply in all material respects with the requirements of the
 Exchange Act and the rules and regulations thereunder, except that no
 representation or warranty is made by the Company with respect to
 statements made or incorporated by reference therein based on information
 supplied by Parent or Sub specifically for inclusion or incorporation by
 reference in the Proxy Statement.

            (g)     Absence of Certain Changes or Events.  Except as set
 forth in the Filed SEC Documents filed after December 31, 1998 and for
 liabilities set forth in this Agreement, since December 31, 1998, (i) the
 Company and its Subsidiaries have conducted their businesses in the
 ordinary course consistent with past practice and (ii) there has not been
 any Material Adverse Change.  Except as set forth in the Filed SEC
 Documents and for actions in the ordinary course of business, consistent
 with past practice, since June 30, 1999, neither the Company nor any
 Subsidiary has taken any action, or failed to take any action, which if
 such action or failure occurred during the period from the date of this
 Agreement to the Effective Time would constitute a material violation of
 Sections 4.1(a) (i), (iii), (iv), (v) (other than with respect to
 licensing), (vi), (vii) or (viii), and neither the Company nor any
 Subsidiary has authorized, or committed or agreed, to take any of such
 actions.

            (h)     Litigation.  There is no suit, action or proceeding
 pending or, to the Knowledge of the Company, threatened against or
 affecting the Company or any of its Subsidiaries or any of their respective
 properties that individually or in the aggregate would have a Material
 Adverse Effect, nor is there any judgment, decree, injunction, rule, order,
 action, demand, or requirement of any Governmental Entity or arbitrator
 outstanding against, or, to the Knowledge of the Company, any  or
 investigation by any Governmental Entity involving, the Company or any of
 its Subsidiaries that individually or in the aggregate would have a
 Material Adverse Effect.

            (i)     Contracts.  As of the date of this Agreement, neither
 the Company nor any Subsidiary is a party to, and none of their respective
 properties or assets are bound by, any material contracts, including
 contracts relating to distribution, sale, licensing, marketing,
 manufacturing, third party suppliers of active ingredients, bulk product
 and finished product to the Company, other than contracts filed as exhibits
 to the SEC Documents.  The Company has not received any notice from any
 other party to any such material contract, and otherwise has no Knowledge
 that such third party intends to terminate, or not renew, any such material
 contract.  As of the date hereof, the Company has made available to Parent
 true and correct copies of all such contracts.  Neither the Company nor any
 of its Subsidiaries, and, to the Knowledge of the Company, no other party
 thereto, is in violation of or in default under (nor does there exist any
 condition which upon the passage of time or the giving of notice or both
 would cause such a violation of or default under) any loan or credit
 agreement, bond, note, mortgage, indenture, lease or other contract,
 agreement, obligation, commitment, arrangement, understanding, instrument,
 permit or license to which it is a party or by which it or any of its
 properties or assets is bound, except for violations or defaults that
 individually or in the aggregate are not reasonably likely to have a
 Material Adverse Effect.  Neither the Company nor any of its Subsidiaries
 is a party to or otherwise bound by any agreement or covenant not to
 compete or by any agreement or covenant restricting in any material respect
 the development, marketing or distribution of the Company's or its
 Subsidiaries' products or services or the conduct of their businesses.

            (j)     Compliance with Laws.

                (i)  Each of the Company and its Subsidiaries is in
      compliance with all statutes, laws, ordinances, rules, regulations,
      judgments, orders and decrees of any Governmental Entity (other than
      Environmental Laws) (collectively, "Legal Provisions") applicable to
      its business or operations, except for instances of possible
      noncompliance that individually or in the aggregate would not have a
      Material Adverse Effect on the Company.  Each of the Company and its
      Subsidiaries has in effect all approvals, authorizations,
      certificates, filings, franchises, licenses, notices, permits and
      rights of or with all Governmental Entities, including all
      authorizations under Environmental Laws ("Permits"), necessary for it
      to own, lease or operate its properties and assets and to carry on its
      business and operations as now conducted, except for the failure to
      have such Permits that individually or in the aggregate would not have
      a Material Adverse Effect on the Company.  There has occurred no
      default under, or violation of, any such Permit, except for defaults
      under, or violations of, Permits that individually or in the aggregate
      would not have a Material Adverse Effect on the Company.  The Merger,
      in and of itself, would not cause the revocation or cancellation of
      any such Permit that individually or in the aggregate is reasonably
      likely to have a Material Adverse Effect on the Company.

                (ii)  Except for those matters that individually or in the
      aggregate are not reasonably likely to have a Material Adverse Effect
      on the Company: (A) each of the Company and its Subsidiaries is, and
      has been, in compliance with all applicable Environmental Laws; (B)
      during the period of ownership or operation by the Company or its
      Subsidiaries of any of its currently or previously owned, leased or
      operated properties, no Hazardous Material has been treated or
      disposed of, and there have been no Releases or threatened Releases of
      Hazardous Material at, in, on, under or affecting such properties or
      any contiguous site; (C) prior to the period of ownership or operation
      by the Company or its Subsidiaries of any of its currently or
      previously owned, leased or operated properties, to the Knowledge of
      the Company, no Hazardous Material was treated, stored, or disposed
      of, and there were no Releases of Hazardous Material at, in, on, under
      or affecting any such property or any contiguous site; and (D) neither
      the Company nor its Subsidiaries have received any written notice of,
      or entered into or assumed by contract, judicial or administrative
      settlement, or operation of law any indemnification obligation, order,
      settlement or decree relating to: (1) any violation of any
      Environmental Laws or the institution or pendency of any suit, action,
      claim, proceeding or investigation by any Governmental Entity or any
      third party in connection with any alleged violation of Environmental
      Laws or any Release of Hazardous Materials, (2) the response to or
      remediation of Hazardous Material at or arising from any of the
      Company's or its Subsidiaries' activities or properties or any other
      properties or (3) payment for any response action relating to or
      remediation of Hazardous Material at or arising from any of the
      Company's or its Subsidiaries' properties, activities, or any other
      properties.  The term "Environmental Laws" means all applicable U.S.,
      U.K., and Dutch laws, statutes, treaties, rules, codes, ordinances,
      regulations, certificates, orders, directives, interpretations,
      licenses, permits, and other authorizations of any Governmental Entity
      and judgments, decrees, injunctions, writs, orders or like action of
      any court, arbitrator or other administrative, judicial or quasi-
      judicial tribunal or agency of competent jurisdiction, including any
      thereof of the European Community or the European Union having the
      force of law in The Netherlands and being applicable to the Company,
      dealing with the protection of health, welfare or the environment,
      including, without limitation, flood, pollution or disaster laws and
      health and environmental protection laws and regulations, and all
      other rules and regulations promulgated thereunder and any provincial,
      municipal, waterboard or other local statute, law, rule, regulation or
      ordinance relating to public or employee health, safety or
      environment; including all laws relating to Releases to air, water,
      land or groundwater, relating to the withdrawal or use of groundwater,
      and relating to the use, handling, transportation, manufacturing,
      introduction into the stream of commerce, or disposal of Hazardous
      Materials.

            The term "Hazardous Materials" means any chemical, material,
 liquid, gas, substance, or waste, whether naturally occurring or man-made,
 that is prohibited, limited, or regulated by or pursuant to an
 Environmental Law.

            The term "Release" means spilling, leaking, discharging,
 injecting, emitting, and or disposing and placement of a Hazardous Material
 in any location that poses a threat thereof.

            (k)     Absence of Changes in Benefit Plans.  There has not
 been any adoption or amendment in any material respect by the Company or
 any of its Subsidiaries of any collective bargaining agreement or any
 Benefit Plan (defined below), or any material change in any actuarial or
 other assumption used to calculate funding obligations with respect to any
 Pension Plans (defined below), or any change in the manner in which
 contributions to any Pension Plans  are made or the basis on which such
 contributions are determined.  As of the date of this Agreement, there
 exist no currently binding employment, consulting, severance, termination
 or indemnification agreements, arrangements or understandings between the
 Company or its Subsidiaries and any current or former officer, director or
 employee of the Company or its Subsidiaries which provide for payments in
 excess of $50,000 and which are not terminable on 60 days or less notice
 without penalty.  There are no collective bargaining or other labor union
 agreements to which the Company or its Subsidiaries is a party or by which
 it is bound.

            (l)     ERISA Compliance.

                (i)  Section 3.1(l)(i) of the Company Disclosure Schedule
      contains a list, and in the case of Subsidiaries, a description of
      each pension, retirement, savings, profit sharing, medical, dental,
      health, disability, life, death benefit, group insurance, deferred
      compensation, stock option, stock purchase, restricted stock, bonus or
      incentive, severance pay, employment or termination, and other
      employee benefit or compensation plan, trust arrangement, contract,
      agreement (including pursuant to any collective bargaining agreement),
      policy, practice or commitment, whether formal or informal, written or
      oral, in each case that are binding commitments of the Company and its
      Subsidiaries, under which (1) current or former employees, directors
      or independent contractors of the Company or any of its Subsidiaries
      participate or are entitled to participate by reason of their
      relationship with the Company or any of its Subsidiaries, (2) to which
      the Company or any of its Subsidiaries is a party or a sponsor or a
      fiduciary thereof or by which the Company or any of its Subsidiaries
      (or any of their rights, properties or assets) is currently bound or
      (3) with respect to which the Company or any of its Subsidiaries has
      any obligation to make payments or contributions, including, without
      limitation,  any employee benefit plan that is subject to or governed
      by the laws of any jurisdiction other than the laws of the United
      States (a "Foreign Plan"), all "employee pension benefit plans" (as
      defined in Section 3(2) of the Employee Retirement Income Security Act
      of 1974, as amended ("ERISA")) (sometimes referred to herein as
      "Pension Plans"), "employee welfare benefit plans" (as defined in
      Section 3(1) of ERISA) (sometimes referred to herein as "Welfare
      Plans") (all of the foregoing referred to collectively herein as
      "Benefit Plans"), and all other Benefit Plans maintained, or
      contributed to, by the Company, its Subsidiaries or any Person or
      entity that, together with the Company, is treated as a single
      employer under Section 414(b), (c), (m) or (o) of the Code (a
      "Commonly Controlled Entity") for the benefit of any current or former
      officers, directors or employees of the Company and its Subsidiaries
      (including any such plans maintained for current or former foreign
      employees).  The Company has made available to Parent true, complete
      and correct copies of (1) each Benefit Plan (or, in the case of any
      unwritten Benefit Plans, descriptions thereof), (2) the most recent
      annual report on Form 5500 required to be filed with the Internal
      Revenue Service (the "IRS") with respect to each Benefit Plan, (3) the
      most recent summary plan description for each Benefit Plan for which
      such summary plan description is required and (4) each trust agreement
      and group annuity contract relating to any Benefit Plan.  Each Benefit
      Plan maintained or contributed to by the Company or any of its
      Subsidiaries has been administered in all material respects in
      accordance with its terms.  The Company, its Subsidiaries and all the
      Benefit Plans maintained or contributed to by the Company or any of
      its Subsidiaries are all in compliance in all material respects with
      the applicable provisions of ERISA, the Code and all other applicable
      laws, including laws of foreign jurisdictions.

                (ii)  All Pension Plans maintained or contributed to by the
      Company or any of its Subsidiaries intended to be tax-qualified have
      been the subject of determination letters from the IRS to the effect
      that such Pension Plans are qualified and exempt from United States
      Federal income taxes under Sections 401(a) and 501(a), respectively,
      of the Code, and no such determination letter has been revoked nor has
      any event occurred since the date of its most recent determination
      letter or application therefor that would adversely affect its
      qualification or materially increase its costs.  All Pension Plans
      maintained or contributed to by the Company or any of its Subsidiaries
      required to have been approved by any foreign Governmental Entity have
      been so approved and no such approval has been revoked nor has any
      event occurred since the date of its most recent approval or
      application therefor that would adversely affect its approval or
      materially increase its costs.

                (iii)  Neither the Company nor any Commonly Controlled
      Entity has (1) at any time in the six years prior to the Closing Date
      maintained or contributed to any Benefit Plan that is subject to Title
      IV of ERISA or Section 412 of the Code or (2) has any unsatisfied
      liability under Title IV of ERISA or Section 412 of the Code.  None of
      the Company, its Subsidiaries, or any Commonly Controlled Entity
      contributes to a "multiemployer plan" as defined in Section 3(37) of
      ERISA.

                (iv)  With respect to any Welfare Plan maintained or
      contributed to by the Company or any of its Subsidiaries, there are no
      understandings, agreements or undertakings, written or oral, that
      would prevent any such plan (including any such plan covering retirees
      or other former employees) from being amended or terminated without
      material liability to the Company on or at any time after the
      Effective Time.

                (v)  No pending or, to the knowledge of the Company,
      threatened disputes, lawsuits, claims (other than routine claims for
      benefits), investigations, audits or complaints to, or by, any person
      or governmental authority have been filed or are pending with respect
      to any Benefit Plans or the Company or any of its Subsidiaries in
      connection with any Benefit Plan or the fiduciaries or administrators
      thereof.  With respect to each Benefit Plan, there has not occurred,
      and no person or entity is contractually bound to enter into, any
      nonexempt "prohibited transaction" within the meaning of Section 4975
      of the Code or Section 406 of ERISA, nor any transaction that would
      result in a civil penalty being imposed under Section 409 or 502(i) of
      ERISA.

                (vi)  There are no unfunded liabilities with respect to any
      Foreign Plan other than would not individually or in the aggregate
      have a Material Adverse Effect on the Company.

                (vii)  All contributions to and payments with respect to or
      under the Benefit Plans that are required to be made with respect to
      periods ending on or before the Effective Time have been made or
      accrued before the Effective Time by the Company in accordance with
      the appropriate plan documents, financial statements, actuarial
      report, collective bargaining agreements or insurance contracts or
      arrangements.

                (viii)  No Welfare Plan providing medical or death benefits
      (whether or not insured) with respect to current or former employees
      of the Company or any Subsidiary continues such coverage or provides
      such benefits beyond their date of retirement or other termination of
      service (other than coverage the cost of which is fully paid by the
      former employee or his or her dependents).

                (ix)  Except as set forth in Section 3.1(l)(ix) of the
      Company Disclosure Schedule, the execution of, and performance of the
      transactions contemplated in, this Agreement will not (either alone or
      upon the occurrence of any additional or subsequent events) constitute
      an event under any plan, policy, arrangement or agreement (including
      under any collective bargaining agreement) or any trust or loan that
      will or would reasonably be expected to result in any payment (whether
      of severance pay or otherwise), acceleration of, forgiveness of
      indebtedness owing from, vesting of, distribution of, or increase in
      or obligation to fund, any benefits with respect to any current or
      former employee, director or consultant of the Company.

            (m)     Labor Relations.  (a)  As of the date hereof, there is
 no pending or, to the Knowledge of the Company, threatened union
 organizational campaign effort, collective bargaining negotiations,
 bargaining impasse, implementation of final offer, labor dispute, grievance
 or arbitration matter, economic or unfair labor practice strike, boycott,
 work stoppage, slowdown, work-to-rule or intermittent strike against the
 Company or any of its Subsidiaries, (b) no lockout is in effect and (c) no
 permanent or temporary strike replacements are currently employed at any
 Company facility.  Neither the Company nor any of its Subsidiaries, nor
 their respective representatives or employees, has committed any unfair
 labor practices in connection with the operation of the respective
 businesses of the Company or any of its Subsidiaries, and there is no
 pending or, to the Knowledge of the Company, threatened charge, complaint,
 decision, order, notice-posting requirement, settlement agreement or
 injunctive action or order against the Company or any of its Subsidiaries
 by the National Labor Relations Board or any similar governmental or
 adjudicatory agency or court, except in each case as would not have a
 Material Adverse Effect on the Company.  The Company and its Subsidiaries
 have in the past been and are in compliance in all respects with all
 applicable collective bargaining agreements and laws respecting employment,
 employment practices, employee classification, labor relations, safety and
 health, wages, hours and terms and conditions of employment, except where
 the failure to be in compliance would not have a Material Adverse Effect on
 the Company.  Neither the Company nor any of its Subsidiaries has
 experienced within the past 12 months a "plant closing" or "mass layoff"
 within the meaning of the Worker Adjustment and Retraining Notification
 Act, 29 U.S.C. sections 2101 et seq.  Section 3.1(m) of the Company
 Disclosure Schedule also sets forth the aggregate number of employees who
 work for the Company and its Subsidiaries, specifying the number of such
 employees who belong to a union or are otherwise covered by an employment
 agreement or a collective bargaining agreement.

            (n)     Taxes.  Each of the Company and its Subsidiaries has
 timely filed all Tax Returns required to be filed by it, or requests for
 extensions to file such Tax Returns have been timely filed and granted and
 have not expired, and all such filed Tax Returns are complete and accurate
 in all respects, except to the extent that failures to (i) file, (ii) have
 extensions granted that remain in effect or (iii) be complete and accurate
 in all respects, as applicable, individually or in the aggregate, would not
 have a Material Adverse Effect.  The Company and each of its Subsidiaries
 has paid (or the Company has paid on its behalf) all Taxes shown as due on
 such Tax Returns, except to the extent that a failure to pay all Taxes
 shown as due on such Tax Returns, individually or in the aggregate, would
 not have a Material Adverse Effect.  The most recent financial statements
 contained in the Filed SEC Documents reflect an adequate reserve for all
 Taxes payable by the Company and its Subsidiaries for all taxable periods
 and portions thereof accrued through the date of such financial statements,
 except to the extent that any failures to reflect such reserves,
 individually or in the aggregate, would not have a Material Adverse Effect.
 No deficiencies for any Taxes have been proposed, asserted or assessed
 against the Company or any of its Subsidiaries that are not adequately
 reserved for on the Company's financial statements in accordance with GAAP
 except to the extent that such Taxes, individually or in the aggregate,
 would not have a Material Adverse Effect.  No requests for waivers of the
 time to assess any Taxes against the Company or any of its Subsidiaries
 have been granted or are pending, except for requests with respect to such
 Taxes that have been adequately reserved for in the most recent financial
 statements contained in the Filed SEC Documents, or, to the extent not
 adequately reserved, the assessment of which would, individually or in the
 aggregate, not have a Material Adverse Effect.  Neither the Company nor any
 of its Affiliates has taken or agreed to take any action or knows of any
 fact or circumstance that is reasonably likely to prevent the Merger from
 qualifying as a reorganization within the meaning of Section 368(a) of the
 Code.  Neither the Company nor any of its Subsidiaries has distributed the
 stock of any corporation in a transaction satisfying the requirements of
 Section 355 of the Code since April 16, 1997.  Neither the stock of the
 Company nor the stock of any of its Subsidiaries has been distributed in a
 transaction satisfying the requirements of Section 355 of the Code since
 April 16, 1997.  As used in this Agreement, "Taxes" shall include all U.S.
 Federal, state and local, domestic and foreign, income, franchise,
 property, sales, use, excise and other taxes, tariffs or governmental
 charges of any nature whatsoever, including any obligations for withholding
 taxes from payments due or made to any other person and any interest,
 penalties or additions to tax and "Tax Returns" shall include any return,
 report or similar statement (including attached schedules) required to be
 filed with respect to any Tax, including, without limitation, any
 information return, claim for refund, amended return or declaration of
 estimated Tax.

            (o)     No Excess Parachute Payments; No Section 162(m)
 Payments.  There will be no payments or benefits to any "disqualified
 individual" (within the meaning of Section 280G of the Code) that would
 constitute or result in an "excess parachute payment" under Section 280G of
 the Code as a direct or indirect consequence of the transactions
 contemplated by this Agreement, including, without limitation, as a result
 of the acceleration of vesting or exercisability of any options to purchase
 Company Common Stock held by "disqualified individuals" as a direct or
 indirect consequence of the transactions contemplated by this Agreement.
 No such Person is entitled to receive any additional payment from the
 Company, the Surviving Corporation or any other Person (a "Parachute Gross
 Up Payment") in the event that the excise tax of Section 4999(a) of the
 Code is imposed on such Person.  The Benefit Plans and other Company
 employee compensation arrangements in effect as of the date of this
 Agreement have been designed so that the disallowance of a deduction under
 Section 162(m) of the Code for employee remuneration will not apply to any
 material amounts paid or payable by the Company or any of its Subsidiaries
 under any such plan or arrangement and, to the Knowledge of the Company, no
 fact or circumstance exists that is reasonably likely to cause such
 disallowance to apply to any such amounts.

            (p)     Title to Properties.

                (i)  Each of the Company and its Subsidiaries has good and
      marketable title to, or valid leasehold interests in, all its material
      properties and assets except for such as are no longer used or useful
      in the conduct of its businesses or as have been disposed of in the
      ordinary course of business and except for defects in title,
      easements, restrictive covenants and similar encumbrances that
      individually or in the aggregate would not materially interfere with
      its ability to conduct its business as currently conducted.  All such
      material assets and properties, other than assets and properties in
      which the Company or any of its Subsidiaries has a leasehold interest,
      are free and clear of all Liens, except for Liens that individually or
      in the aggregate would not materially interfere with the ability of
      the Company and its Subsidiaries to conduct their respective
      businesses as currently conducted.

                (ii)  Each of the Company and its Subsidiaries has complied
      in all material respects with the terms of all material leases to
      which it is a party and under which it is in occupancy, and all such
      leases are in full force and effect, except for such noncompliance or
      failure to be in full force and effect that individually or in the
      aggregate is not reasonably likely to have a Material Adverse Effect.
      Each of the Company and its Subsidiaries enjoys peaceful and
      undisturbed possession under all such material leases, except for
      failures to do so that individually or in the aggregate are not
      reasonably likely to have a Material Adverse Effect.

            (q)     Intellectual Property.  Each of the Company and its
 Subsidiaries owns, or is validly licensed or otherwise has the right to use
 all patents, patent applications, trademarks, trademark rights, trade
 names, trade name rights, service marks, service mark rights, copyrights
 and other proprietary intellectual property rights and computer programs
 (collectively, "Intellectual Property Rights") which if the Company or its
 Subsidiaries did not own or validly license or otherwise have the right to
 use would have a Material Adverse Effect on the Company.  Section 3.1(q) of
 the Company Disclosure Schedule sets forth, as of the date hereof, a list
 of all granted patents, pending patent applications, trademarks and
 applications therefor owned by or licensed to the Company or any of its
 Subsidiaries.  No claims are pending or, to the Knowledge of the Company,
 threatened that the Company or any of its Subsidiaries is infringing the
 rights of any Person with regard to any Intellectual Property Right which
 have or would have a Material Adverse Effect on the Company.  To the
 Knowledge of the Company, no Person is infringing the rights of the Company
 or any of its Subsidiaries with respect to any Intellectual Property Right
 which would have a Material Adverse Effect on the Company.  As of the date
 hereof, the Company has no Knowledge that the business of the Company and
 its Subsidiaries as presently conducted or as presently contemplated does
 or will infringe (i) any granted patent or existing trademark or (ii) any
 patent granted from a pending patent application.  No claims are pending
 or, to the Knowledge of the Company, are threatened challenging the
 ownership of or license to the Intellectual Property Rights owned by or
 licensed to the Company and its Subsidiaries which have or would have a
 Material Adverse Effect on the Company.

            (r)     Voting Requirements.  The affirmative vote of a
 majority of the outstanding shares of Company Common Stock to adopt this
 Agreement (the "Stockholder Approval") is the only vote of the holders of
 any class or series of the Company's capital stock necessary to adopt this
 Agreement and approve the transactions contemplated hereby.

            (s)     State Takeover Statutes.  The Board of Directors of the
 Company has approved the terms of this Agreement and the Option Agreement
 and the consummation of the Merger and the other transactions contemplated
 by this Agreement and the Option Agreement, and such approval represents
 all the action necessary to render inapplicable to this Agreement, the
 Option Agreement, the Merger and the other transactions contemplated by
 this Agreement and the Option Agreement, the provisions of Section 203 of
 the DGCL.  No other state takeover statute or similar statute or regulation
 applies to or purports to apply to this Agreement, the Option Agreement,
 the Merger or the other transactions contemplated by this Agreement or the
 Option Agreement.

            (t)     Brokers.  No broker, investment banker, financial
 advisor or other Person, other than Morgan Stanley & Co. Incorporated, the
 fees and expenses of which will be paid by the Company, is entitled to any
 broker's, finder's, financial advisor's or other similar fee or commission
 in connection with the transactions contemplated by this Agreement and the
 Option Agreement based upon arrangements made by or on behalf of the
 Company.  The Company has delivered to Parent true and complete copies of
 all agreements under which any such fees or expenses are payable and all
 indemnification and other agreements related to the engagement of the
 Persons to whom such fees are payable.

            (u)     Opinion of Financial Advisor.  The Company has received
 the opinion of Morgan Stanley & Co. Incorporated, dated the date hereof, to
 the effect that, as of such date, the Merger Consideration is fair from a
 financial point of view to the holders of shares of Company Common Stock, a
 signed copy of which opinion has been delivered to Parent.

            (v)     Accounting Matters.  Neither the Company nor any of its
 Affiliates has taken or agreed to take any action or knows of any fact or
 circumstance that is reasonably likely to prevent Parent from accounting
 for the business combination to be effected by the Merger as a pooling of
 interests.  The Company's management has consulted with and has made
 representations to its advisors regarding the Company's management's
 conclusion that the Merger will qualify as a pooling of interests business
 combination.  Based upon the Company's management's consultations with its
 advisors, nothing has come to the Company's management's attention that
 would preclude the Merger from qualifying as a pooling of interests
 business combination, subject to the occurrence of any events between (i)
 the initiation and the consummation of the Merger and (ii) for a period of
 two years subsequent to the consummation of the Merger that would preclude
 the Parent from accounting for the Merger as a pooling of interests
 business combination.

            (w)     Supply Relationships.  The Company and its Subsidiaries
 have in place supply agreements or arrangements sufficient to meet the
 needs of the business of the Company as it is currently being conducted,
 and to the knowledge of the Company, no material adverse change in those
 agreements or arrangements is reasonably anticipated.

            (x)     Rights Agreement.  The Company has taken all actions
 necessary to cause the Rights Agreement, dated as of May 19, 1995, between
 the Company and American Stock Transfer and Trust Company of New York, as
 rights agent (the "Rights Agreement") to be amended to (i) render the
 Rights Agreement inapplicable to this Agreement, the Option Agreement, the
 Merger and the other transactions contemplated by this Agreement and the
 Option Agreement, (ii) ensure that (y) none of Parent, Sub or any other
 Subsidiary of Parent is an Acquiring Person (as defined in the Rights
 Agreement) pursuant to the Rights Agreement by virtue of the execution of
 this Agreement and the Option Agreement or the consummation of the Merger
 or the other transactions contemplated by this Agreement and the Option
 Agreement and (z) a Distribution Date or a Stock Acquisition Date (as such
 terms are defined in the Rights Agreement) does not occur by reason of the
 execution of this Agreement and the Option Agreement, the consummation of
 the Merger or the consummation of the other transactions contemplated by
 this Agreement and the Option Agreement and (iii) provide that the
 Expiration Date (as defined in the Rights Agreement) shall occur
 immediately prior to the Effective Time.  A correct and complete copy of
 the Rights Agreement, as amended to date, has been furnished to Parent.

            (y)     Regulatory Compliance.

                (i)  As to each product subject to the jurisdiction of the
      U.S. Food and Drug Administration ("FDA") under the Federal Food, Drug
      and Cosmetic Act and the regulations thereunder ("FDCA") (each such
      product, a "Pharmaceutical Product") that is manufactured, tested,
      distributed and/or marketed by the Company or any of its Subsidiaries,
      such Pharmaceutical Product is being manufactured, tested, distributed
      and/or marketed in substantial compliance with all applicable
      requirements under FDCA and similar Legal Provisions, including those
      relating to investigational use, premarket approval, good
      manufacturing practices, labeling, advertising, record keeping, filing
      of reports and security, except where the failure to be in compliance
      is not reasonably likely to have a Material Adverse Effect on the
      Company.  Neither the Company nor its Subsidiaries has received any
      notice or other communication from the FDA or any other Governmental
      Entity (A) contesting the premarket approval of, the uses of or the
      labeling and promotion of any of the Company's or its Subsidiaries'
      products or (B) otherwise alleging any violation of any Legal
      Provision by the Company or its Subsidiaries which, in either case,
      would have a Material Adverse Effect.

                (ii)  No Pharmaceutical Products have been recalled,
      withdrawn, suspended or discontinued by the Company or any of its
      Subsidiaries in the United States or outside the United States
      (whether voluntarily or otherwise) since January 1, 1998.  No
      proceedings in the United States and outside of the United States of
      which the Company has Knowledge (whether completed or pending) seeking
      the recall, withdrawal, suspension or seizure of any Pharmaceutical
      Product are pending against the Company or any of its Subsidiaries,
      nor have any such proceedings been pending at any time since January
      1, 1998 which would reasonably be expected to have a Material Adverse
      Effect.

                (iii)  As to each biological or drug of the Company or its
      Subsidiaries for which a biological license application, new drug
      application, investigational new drug application or similar state or
      foreign regulatory application has been approved, the Company and its
      Subsidiaries are in substantial compliance with 21 U.S.C. sec. 355 or
      21 C.F.R. Parts 312 or 314 et seq., respectively, and similar Legal
      Provisions and all terms and conditions of such applications, except
      where the failure to be in compliance is not reasonably likely to have
      a Material Adverse Effect on the Company.  As to each such drug, the
      Company and any relevant Subsidiary of the Company, and the officers,
      employees or agents of the Company or such Subsidiary have included in
      the application for such drug, where required, the certification
      described in 21 U.S.C. sec. 335a(k)(1) or any similar Legal Provision
      and the list described in 21 U.S.C. sec. 335a(k)(2) or any similar
      Legal Provision, and such certification and such list was in each case
      true and accurate when made and remained true and accurate thereafter,
      except in the case where the failure of such application to be true
      and accurate would not reasonably be expected to have a Material
      Adverse Effect.  In addition, the Company and its Subsidiaries are in
      substantial compliance with all applicable registration and listing
      requirements set forth in 21 U.S.C. sec. 360 and 21 C.F.R. Part 207
      and all similar Legal Provisions.

                (iv)  Each article of any drug manufactured and/or
      distributed by the Company or any of its Subsidiaries is not
      adulterated within the meaning of 21 U.S.C. sec. 351 (or similar Legal
      Provisions) or misbranded within the meaning of 21 U.S.C. sec. 352 (or
      similar Legal Provisions), and is not a product that is in violation
      of 21 U.S.C. sec. 355 (or similar Legal Provisions), except where such
      failure in compliance with the foregoing would not reasonably be
      expected to have a Material Adverse Effect on the Company.

                (v)  Neither the Company, nor any Subsidiary of the Company,
      nor any officer, employee or agent of either the Company or any
      Subsidiary of the Company has made an untrue statement of a material
      fact or fraudulent statement to the FDA or other Governmental Entity,
      failed to disclose a material fact required to be disclosed to the FDA
      or any other Governmental Entity, or committed an act, made a
      statement, or failed to make a statement that, at the time such
      disclosure was made, could reasonably be expected to provide a basis
      for the FDA or any other Governmental Entity to invoke its policy
      respecting "Fraud, Untrue Statements of Material Facts, Bribery, and
      Illegal Gratuities", set forth in 56 Fed. Reg. 46191 (September 10,
      1991) or any similar policy.  Neither the Company nor any Subsidiary
      of the Company, nor any officer, employee or agent of either the
      Company or any Subsidiary of the Company, has been convicted of any
      crime or engaged in any conduct for which debarment is mandated by 21
      U.S.C. sec. 335a(a) or any similar Legal Provision or authorized by 21
      U.S.C. sec. 335a(b) or any similar Legal Provision.

                (vi)  Except as disclosed in the Filed SEC Documents,
      neither the Company nor any Subsidiary of the Company has received any
      written notice that the FDA or any other Governmental Entity has
      commenced, or threatened to initiate, any action to withdraw its
      approval or request the recall of any product of the Company or any
      Subsidiary, or commenced, or overtly threatened to initiate, any
      action to enjoin production at any facility of the Company or any
      Subsidiary which would reasonably be expected to have a Material
      Adverse Effect.

            (z)     Year 2000 Compliance.  The Company has adopted and
 implemented a commercially reasonable plan to provide (x) that the change
 of the year from 1999 to the year 2000 will not materially and adversely
 affect the information and business systems of the Company or its
 Subsidiaries and (y) that the impacts of such change on the vendors and
 customers of the Company and its Subsidiaries will not have a Material
 Adverse Effect on the Company.  In the Company's reasonable best estimate,
 no expenditures materially in excess of currently budgeted items previously
 disclosed in the Company's Quarterly Report on Form 10-Q for the quarter
 ended June 30, 1999 will be required in order to cause the information and
 business systems of the Company and its Subsidiaries to operate properly
 following the change of the year 1999 to the year 2000.  Between the date
 of this Agreement and the Effective Time, the Company shall continue to use
 reasonable best efforts to implement the plan previously disclosed in the
 Company's Quarterly Report on Form 10-Q for the quarter ended June 30,
 1999.

      Section 3.2    Representations and Warranties of Parent and Sub.
 Except as set forth on the disclosure schedule delivered by Parent to the
 Company prior to the execution of this Agreement, which disclosure schedule
 specifies the section or subsection of this Agreement to which the
 exception relates (the "Parent Disclosure Schedule"), Parent and Sub
 represent and warrant to the Company as follows:

            (a)     Organization, Standing and Corporate Power.  Each of
 Parent and Sub is a corporation duly organized, validly existing and in
 good standing under the laws of the jurisdiction in which it is
 incorporated and has all requisite corporate power and authority to carry
 on its business as now being conducted.  Each of Parent and Sub is duly
 qualified or licensed to do business and is in good standing in each
 jurisdiction in which the nature of its business or the ownership, leasing
 or operation of its properties makes such qualification or licensing
 necessary, other than in such jurisdictions where the failure to be so
 qualified or licensed individually or in the aggregate would not have a
 Material Adverse Effect on Parent.  Parent has made available to the
 Company complete and correct copies of its Restated Certificate of
 Incorporation and Bylaws and the Certificate of Incorporation and Bylaws of
 Sub, in each case as amended to the date hereof.

            Sub was formed solely for the purpose of effecting the Merger
 and, since the date of its incorporation, Sub has not engaged in any
 activities and has not incurred any liabilities or obligations other than
 in connection with its formation and in connection with or as contemplated
 by this Agreement.

            (b)     Subsidiaries.  As of the date hereof, Parent has no
 Subsidiaries other than Sub.  All the outstanding shares of capital stock
 of, or other equity interests, in Sub have been validly issued and are
 fully paid and nonassessable and are owned directly or indirectly by Parent
 free and clear of all Liens, and free of any restriction on the right to
 vote, sell or otherwise dispose of such capital stock or other ownership
 interests.

            (c)     Capital Structure.  The authorized capital stock of
 Parent consists of 120,000,000 shares of Parent Common Stock and 5,524,525
 shares of Preferred Stock, par value $.01 per share ("Preferred Stock").
 At the close of business on September 20, 1999, (i) 63,271,596  shares of
 Parent Common Stock were issued and outstanding, (ii) no shares of Parent
 Common Stock were held by Parent in its treasury, (iii) 7,016,237 shares of
 Parent Common Stock were issuable pursuant to outstanding Parent Stock
 Options, (iv) no shares of Preferred Stock were issued or outstanding, and
 (v) 1,200,000 shares of Series B Junior Preferred Stock were reserved for
 issuance in connection with the rights issued pursuant to the Amended and
 Restated Rights Agreement, dated as of October 31, 1998, by and between the
 Company and American Stock Transfer & Trust Company, as Rights Agent.
 Except as set forth above in this Section 3.2(c) at the close of business
 on September 20, 1999, no shares of capital stock or other voting
 securities of Parent were issued, issuable, reserved for issuance or
 outstanding.  Except as set forth above in this Section 3.2(c), as of the
 date hereof there are no outstanding stock appreciation rights or rights to
 receive shares of Parent Common Stock on a deferred basis granted under any
 employee or director benefit plans or arrangements of Parent or otherwise
 (the "Parent Stock Plans").  All outstanding shares of capital stock of
 Parent are, and all shares which may be issued pursuant to Parent Stock
 Plans will be, when issued in accordance with the terms thereof, duly
 authorized, validly issued, fully paid and nonassessable and not subject to
 preemptive rights.  Except as set forth above in this Section 3.2(c), as of
 the date hereof there are no bonds, debentures, notes or other indebtedness
 of Parent having the right to vote (or convertible into, or exchangeable
 for, securities having the right to vote) on any matters on which
 stockholders of Parent may vote.  Except as set forth above in this Section
 3.2(c) or resulting from the issuance of shares of Parent Common Stock
 pursuant to options or other benefits issued or granted pursuant to the
 Parent Stock Plans outstanding as of the close of business on September 20,
 1999, as of the date hereof (x) there are not issued, issuable, reserved
 for issuance or outstanding (A) any shares of capital stock or other voting
 securities of Parent, (B) any securities of Parent convertible into or
 exchangeable or exercisable for shares of capital stock or voting
 securities of Parent, (C) any warrants, calls, options or other rights to
 acquire from Parent or any Subsidiary of Parent, and no obligation of the
 Parent or any Subsidiary of Parent to issue, any capital stock, voting
 securities or securities convertible into or exchangeable or exercisable
 for capital stock or voting securities of the Parent, and (y) there are not
 any outstanding obligations of the Parent or any Subsidiary of Parent to
 repurchase, redeem or otherwise acquire any such securities or to issue,
 deliver or sell, or cause to be issued, delivered or sold, any such
 securities.

            (d)     Authority; Noncontravention.  Each of Parent and Sub
 has all requisite corporate power and authority to enter into this
 Agreement (and, in the case of Parent, the Option Agreement), and to
 consummate the transactions contemplated by this Agreement (and, in the
 case of Parent, those contemplated by the Option Agreement).  The execution
 and delivery of this Agreement (and, in the case of Parent, the Option
 Agreement) and the consummation of the transactions contemplated by this
 Agreement (and, in the case of Parent, those contemplated by the Option
 Agreement) have been duly authorized by all necessary corporate action on
 the part of Parent and Sub and no other corporate proceedings on the part
 of Parent or Sub are necessary to authorize this Agreement (and, in the
 case of Parent, the Option Agreement) or to consummate the transactions
 contemplated hereby (or, in the case of Parent, those contemplated by the
 Option Agreement).  This Agreement (and, in the case of Parent, the Option
 Agreement) has been duly executed and delivered by Parent and Sub, as
 applicable, and, assuming the due authorization, execution and delivery by
 each of the other parties thereto, constitute legal, valid and binding
 obligations of Parent and Sub, as applicable, enforceable against Parent
 and Sub, as applicable, in accordance with its terms (except insofar as
 enforceability may be limited by applicable bankruptcy, insolvency,
 reorganization, moratorium or other similar laws affecting creditors'
 rights generally or by principles governing availability of equitable
 remedies).

            The execution and delivery of this Agreement and the Option
 Agreement do not, and the consummation of the Merger and the other
 transactions contemplated by this Agreement and the Option Agreement and
 compliance with the provisions of this Agreement and the Option Agreement
 will not, conflict with, or result in any violation of, or default (with or
 without notice or lapse of time, or both) under, or give rise to a right of
 termination, cancellation or acceleration of any obligation or to loss of a
 benefit under, or result in the creation of any Lien upon any of the
 properties or assets of Parent or any of its Subsidiaries under (i) the
 Restated Certificate of Incorporation or Bylaws of Parent or the comparable
 organizational documents of any of its Subsidiaries, (ii) any loan or
 credit agreement, bond, note, mortgage, indenture, lease or other contract,
 agreement, obligation, commitment, arrangement, understanding, instrument,
 permit or license applicable to Parent or any of its Subsidiaries or their
 respective properties or assets or (iii) subject to the governmental
 filings and other matters referred to in the following paragraph, any (A)
 statute, law, ordinance, rule or regulation or (B) judgment, order or
 decree, in each case applicable to Parent or Sub or their respective
 properties or assets, other than, in the case of clauses (ii) and (iii),
 any such conflicts, violations, defaults, rights or Liens that individually
 or in the aggregate would not have a Material Adverse Effect on Parent.

            No consent, approval, order or authorization of, action by or
 in respect of, or registration, declaration or filings with, any
 Governmental Entity is required by or with respect to Parent or any of its
 Subsidiaries in connection with the execution and delivery of this
 Agreement by Parent and Sub (and, in the case of Parent, the Option
 Agreement) or the consummation by Parent and Sub of the Merger or the other
 transactions contemplated by this Agreement (and, in the case of Parent,
 those contemplated by the Option Agreement), except for (1) the filing of a
 premerger notification and report form under the HSR Act and any applicable
 filings and approvals under similar foreign antitrust laws and regulations,
 (2) the filing with the SEC of (A) the Form S-4 and (B) such reports under
 Section 13(a), 13(d), 15(d) or 16(a) of the Exchange Act as may be required
 in connection with this Agreement or the Option Agreement and the
 transactions contemplated by this Agreement or the Option Agreement, (3)
 the filing of the Certificate of Merger with the Secretary of State of the
 State of Delaware and appropriate documents with the relevant authorities
 of other states in which the Company is qualified to do business and such
 filings with Governmental Entities to satisfy the applicable requirements
 of state securities or "blue sky" laws, (4) filings with the Nasdaq and (5)
 such other consents, approvals, orders, authorizations, registrations,
 declarations and filings the failure of which to be obtained or made
 individually or in the aggregate, would not have a material adverse effect
 on Parent.

            (e)     Parent SEC Documents.  Parent has timely filed all
 reports, schedules, forms, statements and other documents (including
 exhibits and other information incorporated therein) with the SEC required
 to be filed by the Company since January 1, 1998 (the "Parent SEC
 Documents").  As of their respective dates, the Parent SEC Documents
 complied in all material respects with the requirements of the Securities
 Act or the Exchange Act, as the case may be, and the rules and regulations
 of the SEC promulgated thereunder applicable to such Parent SEC Documents,
 and none of the Parent SEC Documents contained any untrue statement of a
 material fact or omitted to state a material fact required to be stated
 therein or necessary in order to make the statements therein, in light of
 the circumstances under which they were made, not misleading.  Except to
 the extent that information contained in any Parent SEC Document has been
 revised or superseded by a later-filed SEC Document filed by Parent and
 publicly available prior to the date of this Agreement, none of the Parent
 SEC Documents contains any untrue statement of a material fact or omits to
 state any material fact required to be stated therein or necessary in order
 to make the statements therein, in light of the circumstances under which
 they were made, not misleading.  The financial statements of Parent
 included in the Parent SEC Documents comply in all material respects with
 applicable accounting requirements and the published rules and regulations
 of the SEC with respect thereto, have been prepared in accordance with GAAP
 applied on a consistent basis during the periods involved (except as may be
 indicated in the notes thereto) and fairly present the financial position
 of Parent and its consolidated Subsidiaries as of the dates thereof and the
 consolidated results of their operations and cash flows for the periods
 then ended (subject, in the case of unaudited statements, to normal year-
 end audit adjustments not material in amount).  Except (i) as set forth in
 the Parent SEC Documents or (ii) for liabilities set forth in this
 Agreement or the Option Agreement, neither Parent nor any of its
 Subsidiaries has any liabilities or obligations of any nature (whether
 accrued, absolute, contingent or otherwise) which, individually or in the
 aggregate, would have a Material Adverse Effect on Parent.

            (f)     Information Supplied.  None of the information supplied
 or to be supplied by Parent or Sub specifically for inclusion or
 incorporation by reference in the Form S-4 will, at the time the Form S-4
 becomes effective under the Securities Act, contain any untrue statement of
 a material fact or omit to state any material fact required to be stated
 therein or necessary to make the statements therein, in light of the
 circumstances under which they are made, not misleading, and the Proxy
 Statement will not at the date it is first mailed to the Company's
 stockholders and at the time of the Stockholders Meeting, contain any
 untrue statement of a material fact or omit to state any material fact
 required to be stated therein or necessary in order to make the statements
 therein, in light of the circumstances under which they are made, not
 misleading.  The Form S-4 will comply in all material respects with the
 requirements of the Securities Act and the rules and regulations
 thereunder, except that no representation or warranty is made by Parent or
 Sub with respect to statements made or incorporated by reference therein
 based on information supplied by the Company specifically for inclusion or
 incorporation by reference in the Form S-4.

            (g)     Absence of Certain Changes or Events.  Except for
 liabilities set forth in this Agreement, since December 31, 1998, there has
 not been any Parent Material Adverse Change.

            (h)     Litigation.  There is no suit, action or proceeding
 pending or, to the Knowledge of Parent, threatened against or affecting
 Parent or any of its Subsidiaries or any of their respective properties
 that individually or in the aggregate would have a Material Adverse Effect,
 nor is there any judgment, decree, injunction, rule or order of any
 Governmental Entity or arbitrator outstanding against, or, to the Knowledge
 of Parent, any action, demand, requirement or investigation by any
 Governmental Entity involving, Parent or any of its Subsidiaries that
 individually or in the aggregate would have a Material Adverse Effect.

            (i)     Compliance with Laws.  Each of Parent and its
 Subsidiaries is in compliance with all Legal Provisions applicable to its
 business or operations, except for instances of possible noncompliance that
 individually or in the aggregate would not have a Material Adverse Effect
 on Parent.  Each of Parent and its Subsidiaries has in effect all Permits
 necessary for it to own, lease or operate its properties and assets and to
 carry on its business and operations as now conducted, except for the
 failure to have such Permits that individually or in the aggregate would
 not have a Material Adverse Effect on Parent.  There has occurred no
 default under, or violation of, any such Permit, except for defaults under,
 or violations of, Permits that individually or in the aggregate would not
 have a Material Adverse Effect on Parent.  The Merger, in and of itself,
 would not cause the revocation or cancellation of any such Permit that
 individually or in the aggregate is reasonably likely to have a Material
 Adverse Effect on Parent.

            (j)     Accounting Matters.  Neither Parent nor any of its
 Affiliates has taken or agreed to take any action that would prevent Parent
 from accounting for the business combination to be effected by the Merger
 as a pooling of interests.  Parent's management has consulted with and has
 made representations to its advisors regarding Parent's management's
 conclusion that the Merger will qualify as a pooling of interests business
 combination.  Based upon Parent's management's consultations with its
 advisors, nothing has come to Parent's management's attention that would
 preclude the Merger from qualifying as a pooling of interests business
 combination, subject to the occurrence of any events between (i) the
 initiation and the consummation of the Merger and (ii) for a period of two
 years subsequent to the consummation of the Merger that would preclude the
 Parent from accounting for the Merger as a pooling of interests business
 combination.

            (k)     Tax Matters.  Neither Parent nor any of its Affiliates
 have taken or agreed to take any action or knows of any fact or
 circumstance that is reasonably likely to prevent the Merger from
 qualifying as a reorganization within the meaning of Section 368(a) of the
 Code.  Neither Parent nor any of its Subsidiaries has distributed the stock
 of any corporation in a transaction satisfying the requirements of Section
 355 of the Code since April 16, 1997.  Neither the stock of Parent nor the
 stock of any of its Subsidiaries has been distributed in a transaction
 satisfying the requirements of Section 355 of the Code since April 16,
 1997.

            (l)     Interim Operations of Sub.  Sub was formed solely for
 the purpose of engaging in the transactions contemplated hereby, has
 engaged in no other business activities and has conducted its operations
 only as contemplated hereby.

            (m)     Parent Stockholder Approval.  This Agreement and the
 transactions contemplated hereby, including the issuance of shares of
 Parent Common Stock pursuant to ARTICLE II hereof, does not require the
 approval of the holders of Parent Common Stock.

            (n)     Parent Common Stock.  All outstanding shares of Parent
 Common Stock are, and all shares of Parent Common Stock which may be issued
 pursuant to this Agreement shall be when issued duly authorized, validly
 issued, fully paid and nonassessable and not subject to preemptive rights.

            (o)     Brokers.  No broker, investment banker, financial
 advisor or other Person, other than Merrill Lynch & Co., the fees and
 expenses of which will be paid by Parent, is entitled to any broker's,
 finder's, financial advisors or other similar fee or commission in
 connection with the transactions contemplated by this Agreement based upon
 arrangements made by or on behalf of Parent.

            (p)     Year 2000 Compliance.  Parent has adopted and
 implemented a commercially reasonable plan to provide (x) that the change
 of the year from 1999 to the year 2000 will not materially and adversely
 affect the information and business systems of the Parent or its
 Subsidiaries and (y) that the impacts of such change on the vendors and
 customers of Parent and its Subsidiaries will not have a Material Adverse
 Effect on Parent.  In Parent's reasonable best estimate, no expenditures
 materially in excess of currently budgeted items previously disclosed in
 Parent's Quarterly Report on Form 10-Q for the quarter ended June 30, 1999
 will be required in order to cause the information and business systems of
 Parent and its Subsidiaries to operate properly following the change of the
 year 1999 to the year 2000.  Between the date of this Agreement and the
 Effective Time, Parent shall continue to use reasonable best efforts to
 implement the plan previously disclosed in Parent's Quarterly Report on
 Form 10-Q for the quarter ended June 30, 1999.


                                 ARTICLE IV
                  COVENANTS RELATING TO CONDUCT OF BUSINESS

      Section 4.1    Conduct of Business.

            (a)     Conduct of Business by the Company.  During the period
 from the date of this Agreement to the Effective Time, or the date, if any,
 on which this Agreement is earlier terminated pursuant to Section 7.1, and
 except as may be agreed in writing by Parent, as may be expressly permitted
 pursuant to this Agreement or as set forth in Section 4.1 of the Company
 Disclosure Schedule, the Company shall, and shall cause its Subsidiaries
 to, carry on their respective businesses in the ordinary course consistent
 with past practice and in compliance in all material respects with all
 applicable laws and regulations and, to the extent consistent therewith,
 use all reasonable best efforts to preserve intact its current business
 organizations, keep available the services of its current officers and key
 employees and preserve its relationships with customers, suppliers,
 licensors, licensees, distributors and others having business dealings with
 them with the intention that its goodwill and ongoing business shall be
 preserved.  Without limiting the generality of the foregoing, during the
 period from the date of this Agreement to the Effective Time, or the date,
 if any, on which this Agreement is earlier terminated pursuant to Section
 7.1, and except as may be agreed in writing by Parent, as may be expressly
 permitted pursuant to this Agreement or as set forth in Section 4.1 of the
 Company Disclosure Schedule, the Company shall not, and shall not permit
 any of its Subsidiaries to:

                (i)  (x) declare, set aside or pay any dividends on, or make
      any other distributions (whether in cash, stock or property), in
      respect of, any of its capital stock, other than dividends or
      distributions by a direct or indirect wholly owned Subsidiary of the
      Company to its parent, (y) split, combine or reclassify any of its
      capital stock or amend the terms of any outstanding securities
      (including Stock Options) or (z) purchase, redeem or otherwise acquire
      any shares of its capital stock or any other securities;

                (ii)  issue, deliver, sell, grant, pledge or otherwise
      encumber or subject to any Lien any shares of its capital stock, any
      other securities or any rights, warrants or options to acquire, any
      such shares, or securities (other than (x) the issuance of shares of
      Company Common Stock upon the exercise of Stock Options outstanding on
      the date hereof and in accordance with their terms on the date hereof,
      (y) the issuance of shares of Company Common Stock pursuant to the
      Option Agreement or (z) the issuance of Company Common Stock pursuant
      to Warrants outstanding as of the date of this Agreement in accordance
      with their terms on the date hereof), or any "phantom" stock,
      "phantom" stock rights, stock appreciation rights or stock based
      performance units;

                (iii)  amend its Certificate of Incorporation or Bylaws or
      other comparable charter or organizational documents;

                (iv)  acquire or agree to acquire by merging or
      consolidating with, or by purchasing assets of, or by any other
      manner, any Person or division, business or equity interest of any
      Person other than assets which in the aggregate do not exceed $500,000
      or purchases of raw materials or supplies in the ordinary course of
      business consistent with past practice;

                (v)  sell, lease, license, mortgage or otherwise encumber or
      subject to any Lien or otherwise dispose of any of its properties or
      assets (including securitizations), except sales of inventory in the
      ordinary course of business consistent with past practice and sales of
      goods and services not in excess of $500,000 in the aggregate;

                (vi)  (x) incur any indebtedness for borrowed money or
      guarantee any such indebtedness of another Person, issue or sell any
      debt securities or warrants or other rights to acquire any debt
      securities of the Company or any of its Subsidiaries, guarantee any
      debt securities of another Person, enter into any "keep well" or other
      agreement to maintain any financial statement condition of another
      Person or enter into any arrangement having the economic effect of any
      of the foregoing, except for short-term borrowings incurred in the
      ordinary course of business consistent with past practice or (y) make
      any loans, advances or capital contributions to, or investments in,
      any other Person, other than in the ordinary course of business or to
      or in any direct or indirect wholly owned Subsidiary of the Company;

                (vii)  make or agree to make any new capital expenditure
      (including leases and in-licenses), or enter into any agreement or
      agreements providing for payments which are in excess of $100,000
      individually or $500,000 in the aggregate;

                (viii)  (w) pay, discharge, settle or satisfy any claims,
      liabilities, obligations or litigation (absolute, accrued, asserted or
      unasserted, contingent or otherwise), other than the payment,
      discharge, settlement or satisfaction in the ordinary course of
      business consistent with past practice or in accordance with their
      terms, of liabilities disclosed, reflected or reserved against in the
      most recent consolidated financial statements (or the notes thereto)
      of the Company included in the Filed SEC Documents or incurred since
      the date of such financial statements in the ordinary course of
      business consistent with past practice, (x) cancel any indebtedness,
      (y) waive or assign any claims or rights of substantial value or (z)
      waive any benefits of, or agree to modify in any respect (A) any
      standstill or similar agreements to which the Company or any of its
      Subsidiaries is a party or (B) other than in the ordinary course of
      business, any confidentiality or similar agreements to which the
      Company or any of its Subsidiaries is a party;

                (ix)  except in the ordinary course of business consistent
      with past practice, modify, amend or terminate any material contract
      or agreement to which the Company or any of its Subsidiaries is a
      party, including, without limitation, the agreements referred to in
      Section 4.1(a)(ix) of the Company Disclosure Schedule;

                (x)  enter into any contracts, agreements, binding
      arrangements or understandings relating to the distribution, sale,
      license, marketing or manufacturing by third parties of the Company's
      or its Subsidiaries' products or products licensed by the Company or
      its Subsidiaries, other than pursuant to any such contracts,
      agreements, arrangements or understandings currently in place (that
      have been disclosed in writing to Parent prior to the date hereof) in
      accordance with their terms as of the date hereof;

                (xi)  except as otherwise set forth in this Agreement or as
      required to comply with applicable law, (A) adopt, enter into,
      terminate or amend in any material respect (I) any collective
      bargaining agreement or Benefit Plan or (II) any other agreement, plan
      or policy involving the Company or its Subsidiaries, and one or more
      of its current or former directors, officers, consultants, or
      employees, (B) except as disclosed in writing prior to the date
      hereof, increase in any manner the compensation, bonus or fringe or
      other benefits of, or pay any bonus to, any current or former officer,
      director or employee, other than in the case of employees who are
      neither current nor former officers or directors, increases made in
      connection with normal periodic reviews and related compensation and
      benefit increases which are consistent with past practice, (C) pay any
      benefit or amount not required under any Benefit Plan or any other
      benefit plan or arrangement of the Company or its Subsidiaries as in
      effect on the date of this Agreement, (D) increase in any manner the
      severance or termination pay of any current or former director,
      officer or employee, (E) enter into or amend any employment, deferred
      compensation, consulting, severance, termination or indemnification
      agreement, arrangement or understanding with any current or former
      employee, officer or director, (F) grant any awards under any bonus,
      incentive, performance or other compensation plan or arrangement or
      Benefit Plan (including the grant of stock options, stock appreciation
      rights, performance units, restricted stock, "phantom" stock or other
      stock related awards), or remove any existing restrictions in any
      Benefit Plans or agreements or awards made thereunder, (G) amend or
      modify any Stock Option, (H) take any action to fund or in any other
      way secure the payment of compensation or benefits under any employee
      plan, agreement, contract or arrangement or Benefit Plan, (I) take any
      action to accelerate the vesting of payment of any compensation or
      benefit under any Benefit Plan;

                (xii)  except as otherwise set forth in this Agreement,
      enter into any material agreement, other than contracts for the sale
      of the Company's or its Subsidiaries' products in the ordinary course
      of business, other than pursuant to any contracts, agreements,
      arrangements or understandings currently in place (that have been
      disclosed in writing to Parent prior to the date of this Agreement);

                (xiii)  except as required by GAAP, make any change in
      accounting methods, principles or practices;

                (xiv)  take any action that would, or that could reasonably
      be expected to, result in (i) any of the representations and
      warranties of the Company set forth in this Agreement or the Option
      Agreement that are qualified by materiality becoming untrue, (ii) any
      of such representations and warranties that are not so qualified
      becoming untrue in any material respect or (iii) any of the conditions
      to the Merger set forth in ARTICLE VI not being satisfied;

                (xv)  transfer or license to any Person or otherwise extend,
      amend or modify any rights to the Intellectual Property Rights of the
      Company and its Subsidiaries other than pursuant to any contracts,
      agreements, arrangements or understandings currently in place (that
      have been disclosed in writing to Parent prior to the date of this
      Agreement); or

                (xvi)  authorize, or commit or agree to take, any of the
      foregoing actions.

            (b)     Conduct of Business by Parent.  During the period from
 the date of this Agreement to the Effective Time or the date, if any, on
 which this Agreement is earlier terminated pursuant to Section 7.1, and
 except as may be agreed in writing by the Company, or as may be
 contemplated by this Agreement or Section 4.1(b) of the Parent Disclosure
 Schedule, (i) Parent shall and shall cause its Subsidiaries to carry on
 their respective businesses in all material respects in the ordinary course
 and (ii) Parent shall not, and shall not permit any of its Subsidiaries to:

                (i)  (x) declare, set aside or pay any dividends on, or make
      any other distributions (whether in cash, stock or property), in
      respect of, any of its capital stock, other than dividends or
      distributions by a direct or indirect wholly owned Subsidiary of
      Parent to its parent, or (y) split, combine or reclassify any of its
      capital stock;

                (ii)  amend its Certificate of Incorporation or other
      comparable charter or organizational documents;

                (iii)  take any action that would reasonably be expected to
      prevent, impair or materially delay the ability of the Company or
      Parent to consummate the transactions contemplated by this Agreement;

                (iv)  take any action that would, or that could reasonably
      be expected to, result in (x) any of the representations and
      warranties of Parent set forth in this Agreement that are qualified by
      materiality becoming untrue, (y) any of such representations and
      warranties that are not so qualified becoming untrue in any material
      respect or (z) any of the conditions to the Merger set forth in
      ARTICLE VI not being satisfied; or

                (v)  authorize, or commit or agree to take, any of the
      foregoing actions.

            (c)     Advice of Changes.  The Company and Parent shall
 promptly advise the other party orally and in writing of (i) any
 representation or warranty made by it (and, in the case of Parent, made by
 Sub) contained in this Agreement or the Option Agreement that is qualified
 as to materiality becoming untrue or inaccurate in any respect or any such
 representation of warranty that is not so qualified becoming untrue or
 inaccurate in any material respect, (ii) the failure of it (and, in the
 case of Parent, by Sub) to comply with or satisfy in any material respect
 any covenant, condition or agreement to be complied with or satisfied by it
 under this Agreement or the Option Agreement; provided, however, that no
 such notification shall affect the representations, warranties, covenants
 or agreements of the parties (or remedies with respect thereto) or the
 conditions to the obligations of the parties under this Agreement or the
 Option Agreement, (iii) any fact or development which would result in the
 failure of any condition hereto not to be satisfied, (iv) any notice or
 claim by any third party that its consent is or may be required in
 connection with the transactions contemplated hereby and (v) any
 communication from any governmental entity in connection with the
 transactions contemplated hereby.

            (d)     Certain Tax Matters.  From the date hereof until the
 Effective Time, (i) the Company will promptly notify Parent of any action,
 suit, proceeding, claim or audit (collectively, "Actions") pending against
 or with respect to the Company or its Subsidiaries in respect of any Tax
 where there is a reasonable possibility of a determination or decision with
 respect to the Company's Tax liabilities or Tax attributes that is
 reasonably likely to have a Material Adverse Effect on the Company and the
 Company will not settle or compromise any such Action without Parent's
 prior written consent, which consent shall not be unreasonably withheld,
 and (ii) the Company and its Subsidiaries will not make any material Tax
 election, or change any material Tax accounting method, principle or
 practice, without the prior written consent of Parent, which consent will
 not be unreasonably withheld.

      Section 4.2    No Solicitation.

            (a)     The Company shall not, nor shall it authorize or permit
 any of its Subsidiaries, any of their respective officers, directors or
 employees or any investment banker, financial advisor, attorney, accountant
 or other advisor or representative retained by the Company or its
 Subsidiaries, directly or indirectly through another Person, (i) to
 solicit, initiate or encourage (including by way of furnishing
 information), or take any action designed or reasonably likely to
 facilitate, the making of a proposal which constitutes, or may reasonably
 be expected to lead to, any Takeover Proposal or (ii) participate in any
 discussions or negotiations regarding any Takeover Proposal; provided,
 however, that if, at any time prior to the Stockholder Approval, the Board
 of Directors of the Company determines in good faith, based on advice of
 outside counsel, that failure to do so would be reasonably likely to result
 in a breach of its fiduciary duties under applicable law, the Company may,
 in response to a Superior Proposal that was unsolicited and that did not
 otherwise result from a breach of this Section 4.2, and subject to
 providing prior written notice of its decision to take such action to
 Parent (the "Company Notice") and compliance with Section 4.2(c), (x)
 furnish information with respect to the Company to the Person making the
 Superior Proposal pursuant to a customary and reasonable confidentiality
 agreement no less favorable to the Company than the Confidentiality
 Agreement (as defined below) and (y) participate in discussions or
 negotiations regarding such Superior Proposal.  The Company and its
 Subsidiaries, their respective officers, directors and employees and any
 investment banker, financial advisor, attorney, accountant and other
 advisor or representative retained by the Company or its Subsidiaries shall
 immediately cease any existing discussions regarding any Takeover Proposal.

            (b)     Neither the Company, nor the Board of Directors of the
 Company nor any committee thereof shall withdraw or modify, or propose
 publicly to withdraw or modify, in a manner adverse to Parent or Sub, the
 approval or recommendation by such Board of Directors or any such committee
 of this Agreement or the Merger.  Neither the Company, nor the Board of
 Directors of the Company nor any committee thereof shall (i) cause the
 Company to enter into any letter of intent, agreement in principle,
 acquisition agreement or other similar agreement (each, an "Acquisition
 Agreement") related to any Takeover Proposal, (ii) approve or recommend, or
 propose publicly to approve or recommend, any Takeover Proposal, (iii) (x)
 redeem the Rights, (y) waive or amend any provisions of the Rights
 Agreement or (z) take any action with respect to, or make any determination
 under, the Rights Agreement, or (iv) waive or fail to enforce the terms of
 any confidentiality or standstill agreement, in any such case to permit or
 facilitate a Takeover Proposal.  Notwithstanding the foregoing, at any time
 before the Stockholder Approval, in response to a Superior Proposal which
 was unsolicited and which did not otherwise result from a breach of this
 Section 4.2, the Board of Directors of the Company may (subject to this
 sentence and the definition of the term "Superior Proposal") terminate this
 Agreement and concurrently with such termination cause the Company to enter
 into a definitive Acquisition Agreement with respect to such Superior
 Proposal (the determination of whether a proposal is a Superior Proposal to
 be made after consideration of any modification proposed by Parent), but
 only (x) at a time that is after the fifth day following Parent's receipt
 of written notice advising Parent that the Board of Directors of the
 Company is prepared to accept such Superior Proposal, specifying the
 material terms and conditions of such Superior Proposal (including a copy
 of any proposed agreement) and identifying the person making such Superior
 Proposal and (y) after Parent shall have received the Termination Fee and
 the Expenses.

            (c)     In addition to the obligations of the Company set forth
 in Section 4.2(a) and Section 4.2(b) hereof, the Company promptly shall
 advise Parent orally and in writing of any request for information or of
 any Takeover Proposal, or any inquiry with respect to or which could lead
 to any Takeover Proposal, the material terms and conditions of such
 request, Takeover Proposal or inquiry, and the identity of the Person
 making any such request, Takeover Proposal or inquiry.  The Company will
 keep Parent informed on a prompt basis of the status and details (including
 amendments or proposed amendments) of any such request, Takeover Proposal
 or inquiry.  The Company will promptly provide Parent with a copy of any
 written materials received from any third party with respect to or which
 could lead to any Takeover Proposal and of any materials provided to such
 third party.  The Company shall immediately provide Parent with any such
 information or materials if so requested by Parent.

            (d)     Nothing contained in this Section 4.2 shall prohibit
 the Company from (x) taking and disclosing to its stockholders a position
 contemplated by Rule 14e-2(a) promulgated under the Exchange Act or (y)
 making any disclosure to the Company's stockholders if, in the good faith
 judgment of the majority of the members of the Board of Directors of the
 Company, based on advice of outside counsel, failure to so disclose would
 be inconsistent with its duties under applicable law; provided, subject to
 Section 4.2(b) that neither the Company nor its Board of Directors nor any
 committee thereof shall withdraw or modify, or propose publicly to withdraw
 or modify, its position with respect to this Agreement or the Merger or
 approve or recommend, or propose publicly to approve or recommend, a
 Takeover Proposal.


                                  ARTICLE V
                            ADDITIONAL AGREEMENTS

      Section 5.1    Preparation of the Form S-4 and the Proxy Statement;
 Stockholders Meeting.

            (a)     As soon as practicable following the date of this
 Agreement, the Company and Parent shall prepare and the Company shall file
 with the SEC the Proxy Statement and Parent shall prepare and file with the
 SEC the Form S-4, in which the Proxy Statement will be included as a
 prospectus.  Each of the Company and Parent shall use its reasonable best
 efforts to have the Form S-4 declared effective under the Securities Act as
 promptly as practicable after such filing.  The Company will use its
 reasonable best efforts to cause the Proxy Statement to be mailed to the
 Company's stockholders as promptly as practicable after the Form S-4 is
 declared effective under the Securities Act.  Parent shall also take any
 action (other than qualifying to do business in any jurisdiction in which
 it is not now so qualified or to file a general consent to service of
 process) required to be taken under any applicable state securities laws in
 connection with the issuance of Parent Common Stock in the Merger and the
 Company shall furnish all information concerning the Company and the
 holders of Company Common Stock as may be reasonably requested in
 connection with any such action and the preparation, filing and
 distribution of the Proxy Statement.  No filing of, or amendment or
 supplement to, the Form S-4 will be made by Parent, or to the Proxy
 Statement will be made by the Company, without providing the other party
 the opportunity to review and comment thereon.  Parent will advise the
 Company, promptly after it receives notice thereof, of the time when the
 Form S-4 has become effective, the issuance of any stop order, the
 suspension of the qualification of Parent Common Stock issuable in
 connection with the Merger for offering or sale in any jurisdiction, or any
 request by the SEC for amendment of the Form S-4 or comments thereon and
 responses thereto or requests by the SEC for additional information.  The
 Company will advise Parent, promptly after it receives notice thereof, of
 any request by the SEC for amendment of the Proxy Statement or comments
 thereon and responses thereto or requests by the SEC for additional
 information.  If at any time prior to the Effective Time any information
 relating to the Company or Parent, or any of their respective Affiliates,
 officers or directors, should be discovered by the Company or Parent which
 should be set forth in an amendment or supplement to any of the Form S-4 or
 the Proxy Statement, so that any of such documents would not include any
 misstatement of a material fact or omit to state any material fact
 necessary to make the statements therein, in light of the circumstances
 under which they were made, not misleading, the party which discovers such
 information shall promptly notify the other parties hereto and an
 appropriate amendment or supplement describing such information shall be
 promptly filed with the SEC and, to the extent required by law,
 disseminated to the stockholders of the Company.

            (b)     The Company will, as soon as reasonably practicable,
 establish a record date for, duly call, give notice of, convene and hold a
 meeting of its stockholders (the "Stockholders Meeting") for the purpose of
 obtaining the Stockholder Approval.  Unless the Company has terminated this
 Agreement pursuant to Section 4.2(b) hereof, the Company will, through its
 Board of Directors, recommend to its stockholders adoption of this
 Agreement.  Without limiting the generality of the foregoing, the Company
 agrees that its obligations pursuant to this Section 5.1(b) shall not be
 affected by the commencement, public proposal, public disclosure or
 communication to the Company of any Takeover Proposal.

      Section 5.2    Letters of the Company's Accountants.

            (a)     The Company shall use its reasonable best efforts to
 cause to be delivered to Parent two letters from Ernst & Young LLP, the
 Company's independent public accountants, one dated a date within two
 Business Days before the date on which the Form S-4 shall become effective
 and one dated a date within two Business Days before the Closing Date, each
 addressed to Parent and the Company, in form and substance reasonably
 satisfactory to Parent and customary in scope and substance for comfort
 letters delivered by independent public accountants in connection with
 registration statements similar to the Form S-4.

            (b)     The Company shall use its reasonable best efforts to
 cause to be delivered to Parent a letter from Ernst & Young LLP, addressed
 to Parent and the Company, dated as of the Closing Date, stating that (i)
 Ernst & Young LLP concurs with the Company management's conclusion that,
 subject to customary qualifications, the Company meets the requirements to
 be a party to a pooling of interests transaction for financial reporting
 purposes under Opinion 16 of the Accounting Principles Board and applicable
 SEC rules and regulations and (ii) the basis for such a concurrence is
 Ernst & Young LLP's belief that the criteria for such accounting treatment
 have been met.

      Section 5.3    Letters of Parent's Accountants.

            (a)     Parent shall use its reasonable best efforts to cause
 to be delivered to the Company two letters from PricewaterhouseCoopers LLP,
 Parent's independent public accountants, one dated a date within two
 Business Days before the date on which the Form S-4 shall become effective
 and one dated a date within two Business Days before the Closing Date, each
 addressed to the Company and Parent, in form and substance reasonably
 satisfactory to the Company and customary in scope and substance for
 comfort letters delivered by independent public accountants in connection
 with registration statements similar to the Form S-4.

            (b)     Parent shall use its reasonable best efforts to cause
 to be delivered to the Company a letter from PricewaterhouseCoopers LLP,
 addressed to the Company and Parent, dated as of the Closing Date, stating
 that (i) PricewaterhouseCoopers LLP concurs with Parent's management's
 conclusion that, subject to customary qualifications, the Merger qualifies
 for pooling of interests treatment for financial reporting purposes under
 Opinion 16 of the Accounting Principles Board and applicable SEC rules and
 regulations and (ii) the basis for such a concurrence is
 PricewaterhouseCoopers LLP's belief that the criteria for such accounting
 treatment have been met.

      Section 5.4    Access to Information; Confidentiality.

            (a)     Subject to the Confidentiality Agreement dated as of
 September 7, 1999, between Parent and the Company (as it may be amended
 from time to time, the "Confidentiality Agreement"), the Company shall
 afford to Parent, and to Parent's officers, employees, accountants,
 counsel, financial advisors and other representatives, reasonable access
 during normal business hours during the period prior to the Effective Time
 or the termination of this Agreement to all its properties, books,
 contracts, commitments, personnel and records and, during such period, the
 Company shall furnish promptly to Parent (a) a copy of each report,
 schedule, registration statement and other document filed by it during such
 period pursuant to the requirements of United States Federal or state
 securities laws and (b) all other information concerning its business,
 properties and personnel as Parent may reasonably request.  Except as
 required by law, Parent will hold, and will cause its officers, employees,
 accountants, counsel, financial advisors and other representatives and
 Affiliates to hold, any nonpublic information received from the Company,
 directly or indirectly, in accordance with the Confidentiality Agreement.
 Parent will make all reasonable best efforts to minimize disruption to the
 business of the Company and its Subsidiaries which may result from the
 requests for data and information hereunder.  All requests for access and
 information shall be coordinated through senior executives of the parties
 to be designated.

            (b)     Subject to the Confidentiality Agreement, Parent agrees
 to provide to the Company, from time to time prior to the date on which
 Stockholder Approval is obtained, such information as the Company shall
 reasonably request to evaluate Parent and its business, financial
 condition, operations and prospects and shall furnish promptly to the
 Company a copy of each report, schedule, registration statement and other
 document filed by it during such period pursuant to the requirements of
 United States Federal or state securities laws.  Except as provided by law,
 the Company will hold, and will cause its officers and employees to hold,
 any nonpublic information received from Parent, directly or indirectly, in
 accordance with the Confidentiality Agreement.  The Company will make all
 reasonable best efforts to minimize disruption to the business of the
 Parent and its Subsidiaries which may result from the requests for data and
 information hereunder.  All requests for access and information shall be
 coordinated through senior executives of the parties to be designated.

      Section 5.5    Reasonable Best Efforts.  Upon the terms and subject to
 the conditions set forth in this Agreement, each of the parties agrees to
 use its reasonable best efforts to take, or cause to be taken, all actions,
 and to do, or cause to be done, and to assist and cooperate with the other
 parties in doing, all things necessary, proper or advisable to consummate
 and make effective, in the most expeditious manner practicable, the Merger
 and the other transactions contemplated by this Agreement and the Option
 Agreement, including using reasonable best efforts to accomplish the
 following: (i) the taking of all reasonable acts necessary to cause the
 conditions to Closing to be satisfied, (ii) the obtaining of all necessary
 actions or nonactions, waivers, consents and approvals from Governmental
 Entities and the making of all necessary registrations and filings
 (including filings with Governmental Entities, if any) and the taking of
 all reasonable steps as may be necessary to obtain an approval or waiver
 from, or to avoid an action or proceeding by any Governmental Entity, (iii)
 the obtaining of all necessary consents, approvals or waivers from third
 parties (provided that if obtaining any such consent, approval or waiver
 would require any action other than the payment of a nominal amount, such
 action shall be subject to the consent of Parent, not to be unreasonably
 withheld), (iv) the defending of any lawsuits or other legal proceedings,
 whether judicial or administrative, challenging this Agreement or the
 Option Agreement or the consummation of the transactions contemplated
 hereby or thereby, including seeking to have any stay or temporary
 restraining order entered by any court or other Governmental Entity vacated
 or reversed and (v) the execution and delivery of any additional
 instruments necessary to consummate the transactions contemplated by, and
 to fully carry out the purposes of, this Agreement and the Option
 Agreement.  In connection with and without limiting the foregoing, the
 Company and its Board of Directors shall if any state takeover statute or
 similar statute becomes applicable to this Agreement, the Option Agreement,
 the Merger or any other transactions contemplated by this Agreement or the
 Option Agreement, take all action necessary to ensure that the Merger and
 the other transactions contemplated by this Agreement and the Option
 Agreement may be consummated as promptly as practicable on the terms
 contemplated by this Agreement and the Option Agreement and otherwise to
 minimize the effect of such statute or regulation on this Agreement, the
 Option Agreement, the Merger and the other transactions contemplated by
 this Agreement and the Option Agreement.  Nothing in this Agreement shall
 be deemed to require Parent to agree to, or proffer to, divest or hold
 separate any assets or any portion of any business of Parent, the Company
 or any of their respective Subsidiaries.

      Section 5.6    Stock Options.

            (a)     As of the Effective Time, each outstanding option to
 purchase shares of Company Common Stock (a "Stock Option") granted under
 any plan or arrangement providing for the grant of options to purchase
 shares of Company Common Stock to current or former officers, directors,
 employees or consultants of the Company or its Subsidiaries (the "Company
 Stock Plans"), whether vested or unvested,  shall be converted into an
 option to acquire, on the same terms and conditions as were applicable
 under the Stock Option, the number of shares of Parent Common Stock
 (rounded to the nearest whole share) determined by multiplying the number
 of shares of Company Common Stock subject to such Stock Option by the
 Exchange Ratio, at a price per share of Parent Common Stock equal to (A)
 the aggregate exercise price for the shares of Company Common Stock
 otherwise purchasable pursuant to such Stock Option divided by (B) the
 aggregate number of shares of Parent Common Stock deemed purchasable
 pursuant to such Stock Option (each, as so adjusted, an "Adjusted Option");
 provided that such exercise price shall be rounded up to the nearest whole
 cent.  The transactions contemplated by this Agreement constitute a 'change
 in control' for purposes of the Company Stock Plans.

            (b)     The adjustments provided herein with respect to any
 Stock Options that are "incentive stock options" as defined in Section 422
 of the Code shall be and are intended to be effected in a manner which is
 consistent with Section 424(a) of the Code.

            (c)     At the Effective Time, by virtue of the Merger and
 without the need of any further corporate action, Parent shall assume the
 Company Stock Plans, with the result that all obligations of the Company
 under the Company Stock Plans, including with respect to Stock Options
 outstanding at the Effective Time, shall be obligations of Parent following
 the Effective Time.

            (d)     At or prior to the Effective Time, Parent shall take
 all corporate action necessary to reserve for issue a sufficient number of
 shares of Parent Common Stock for delivery upon exercise of Stock Options.
 As soon as practicable after the Effective Time, Parent shall file a
 Registration Statement on Form S-3 or Form S-8 as the case may be (or any
 successor or other appropriate forms), with respect to the shares of Parent
 Common Stock subject to such Stock Options, and shall maintain the
 effectiveness of such registration statement and the current status of the
 prospectus or prospectuses contained therein, for so long as such Stock
 Options remain outstanding.

            (e)     Parent shall take, and shall cause the Surviving
 Corporation and its Subsidiaries and all other affiliates of Parent to
 take, the following actions:  (i) waive any limitations regarding pre-
 existing conditions and eligibility waiting periods under any welfare or
 other employee benefit plan maintained by any of them for the benefit of
 employees of the Company or any of its Subsidiaries immediately prior to
 the Effective Time (the "Employees") to the extent such pre-existing
 condition or waiting period did not apply to the Employee under a
 comparable plan of the Company immediately prior to the Effective Time,
 (ii) provide each Employee with credit for any co-payments and deductibles
 paid prior to the Effective Time for the calendar year in which the
 Effective Time occurs, in satisfying any applicable deductible or out-of-
 pocket requirements under such welfare plans or other employee benefit
 plans, and (iii) for all purposes (other than for purposes of benefit
 accruals under any defined benefit pension plan) under all compensation and
 benefit plans and policies applicable to the employees, treat all service
 by the Employees with the Company or any of its Subsidiaries or Affiliates
 before the Effective Time as service with Parent and its Subsidiaries and
 Affiliates.

      Section 5.7    Indemnification, Exculpation and Insurance.

            (a)     Parent agrees that all rights to indemnification and
 exculpation from liabilities for acts or omissions occurring at or prior to
 the Effective Time now existing in favor of the current or former directors
 or employees or officers of the Company as provided in the Company
 Certificate of Incorporation, the Bylaws or any indemnification agreement
 between such directors or officers and the Company (in each case, as in
 effect on the date hereof) shall be assumed by the Surviving Corporation in
 the Merger, without further action, as of the Effective Time and shall
 survive the Merger and shall continue in full force and effect in
 accordance with their terms.

            (b)     For six years after the Effective Time, Parent shall
 cause the Company to maintain in effect the Company's current officers',
 directors' and employees' liability insurance in respect of acts or
 omissions occurring at or prior to the Effective Time, covering each Person
 currently covered by the Company's officers' and directors' liability
 insurance policy (a copy of which has been heretofore delivered to Parent),
 on terms with respect to such coverage and amount no less favorable than
 those of such policy in effect on the date hereof; provided that Parent may
 substitute therefor policies of Parent containing terms with respect to
 coverage and amount no less favorable to such directors and officers;
 provided, however, that in satisfying its obligation under this Section
 5.7(b) Parent shall not be obligated to pay premiums in excess of 200% of
 the amount per annum paid by the Company in its last full fiscal year; and
 provided further that if Parent is not able to obtain such coverage for
 such 200% amount, Parent shall nevertheless be obligated to provide such
 coverage as may be obtained for such 200% amount.

            (c)     The provisions of this Section 5.7 are (i) intended to
 be for the benefit of, and will be enforceable by, each indemnified party,
 his or her heirs and his or her representatives and (ii) in addition to,
 and not in substitution for, any other rights to indemnification or
 contribution that any such Person may have by contract or otherwise.

      Section 5.8    Fees and Expenses.

            (a)     Except as provided below, all fees and expenses
 incurred in connection with this Agreement, the Option Agreement, the
 Merger and the other transactions contemplated by this Agreement and the
 Option Agreement shall be paid by the party incurring such fees or
 expenses, whether or not the Merger is consummated, except that each of
 Parent and the Company shall bear and pay one-half of (i) the costs and
 expenses incurred in connection with filing, printing and mailing the Proxy
 Statement and the Form S-4 and (ii) the filing fees for the premerger
 notification and report forms under the HSR Act and any similar foreign
 antitrust laws.

            (b)     In the event that (1) a bona fide Takeover Proposal
 shall have been publicly disclosed or has been made directly to the
 Company's stockholders or any Person has announced an intention (whether or
 not conditional) to make a bona fide Takeover Proposal and thereafter this
 Agreement is terminated by either (x) Parent or the Company pursuant to
 Section 7.1(b)(iii) or (y) by Parent pursuant to Section 7.1(d) (provided
 that the breach or failure to perform giving rise to Parent's right to
 terminate under Section 7.1(d)  shall be willful and material) and, in
 either case, within 12 months of termination the Company enters into an
 Acquisition Agreement with respect to a Takeover Proposal or a Takeover
 Proposal is consummated or (2) this Agreement is terminated (x) by the
 Company pursuant to Section 7.1(f) or (y) by Parent pursuant to Section
 7.1(e),  then the Company shall pay Parent a fee equal to $15 million (the
 "Termination Fee"), payable by wire transfer of immediately available
 funds, such payment to be made (A) in the case of the termination
 contemplated by clause (1), on the earlier of the date the Company enters
 into an Acquisition Agreement or a Takeover Proposal is consummated, (B) in
 the case of a termination contemplated by clause (2)(x), no later than
 immediately prior to such termination and (c) in the case of termination
 contemplated by clause 2(y), no later than the date of such termination.
 Simultaneously with the payment of the Termination Fee, the Company shall
 reimburse Parent for all of its documented out-of-pocket expenses incurred
 in connection with this Agreement and the transactions contemplated hereby
 (including documented fees and expenses of accountants, attorneys and
 financial advisors) up to an aggregate of $2,000,000 (the "Expenses").  The
 Company acknowledges that the agreements contained in this Section 5.8(b)
 are an integral part of the transactions contemplated by this Agreement,
 and that, without these agreements, Parent would not enter into this
 Agreement.  If Parent shall successfully bring an action to enforce its
 rights under this Section 5.8(b), the Company shall reimburse Parent for
 its reasonable fees and expenses in connection therewith and shall pay
 Parent interest on the Termination Fee and Expenses from the date the
 Termination Fee becomes payable to the date of payment at the publicly
 announced prime rate of Citibank, N.A. in effect on the date the
 Termination Fee became payable.

      Section 5.9    Public Announcements.  Parent and the Company will
 consult with each other before issuing, and give each other the opportunity
 to review and comment upon, any press release or other public statements
 with respect to the transactions contemplated by this Agreement, including
 the Merger and the Option Agreement, and shall not issue any such press
 release or make any such public statement prior to such consultation,
 except as may be required by applicable law, court process or by
 obligations pursuant to any listing agreement with any national securities
 exchange or national securities quotation system.  The parties agree that
 the initial press release to be issued with respect to the transactions
 contemplated by this Agreement and the Option Agreement shall be in the
 form heretofore agreed to by the parties.

      Section 5.10   Affiliates.

            (a)     As soon as practicable after the date hereof, and in no
 event more than 45 days prior to the date of the Stockholders Meeting, the
 Company shall deliver to Parent a letter identifying all Persons who are at
 the time this Agreement is submitted for adoption by the stockholders of
 the Company, "affiliates" of the Company for purposes of Rule 145 under the
 Securities Act or for purposes of qualifying the Merger for pooling of
 interests accounting treatment under Opinion 16 of the Accounting
 Principles Board and its related interpretations and applicable SEC rules
 and regulations.  The Company shall use its reasonable best efforts to
 cause each such Person to deliver to Parent at least 30 days prior to the
 Closing Date a written agreement substantially in the form attached as
 Exhibit A hereto.

            (b)     As soon as practicable after the date hereof, and in no
 event more than 45 days prior to the date of the Company Stockholder
 Meeting, Parent shall deliver to the Company a letter identifying all
 Persons who are at the time this Agreement is submitted for adoption by the
 stockholders of the Company, "affiliates" of the Parent for purposes of
 qualifying the Merger for pooling of interests accounting treatment under
 Opinion 16 of the Accounting Principles Board and its related
 interpretations and applicable SEC rules and regulations.  Parent shall use
 its reasonable best efforts to cause each such Person to deliver to Parent
 at least 30 days prior to the Closing Date a written agreement
 substantially in the form attached as Exhibit B hereto.

      Section 5.11   Stock Exchange Listing.  To the extent Parent does not
 issue treasury shares in the Merger which are already listed, Parent shall
 use its reasonable best efforts to cause the shares of Parent Common Stock
 to be issued in the Merger to be approved for listing on the Nasdaq,
 subject to official notice of issuance, prior to the Closing Date.  The
 Company shall use its reasonable best efforts to cause the shares of
 Company Common Stock to be issued pursuant to the Option Agreement to be
 approved for quotation on Nasdaq, as promptly as practicable after the date
 hereof, and in any event prior to the earlier of (x) the Closing Date or
 (y) termination of this Agreement under circumstances where the Option
 issued pursuant to the Option Agreement is or may become exercisable by
 Parent.

      Section 5.12   Pooling of Interests.  Each of the Company and Parent
 will use reasonable best efforts to cause the Merger to be accounted for as
 a pooling of interests under Opinion 16 of the Accounting Principles Board
 and its related interpretations and applicable SEC rules and regulations,
 and such accounting treatment to be accepted by each of the Company's and
 Parent's independent public accountants, and by the SEC, respectively, and
 each of the Company and Parent agrees that it will voluntarily take no
 action that would cause such accounting treatment not to be obtained.

      Section 5.13   Tax Treatment.  Parent and the Company intend that the
 Merger will qualify as a reorganization within the meaning of Section
 368(a) of the Code.  Parent and the Company shall each use all reasonable
 efforts to cause the Merger to so qualify.

      Section 5.14   Stockholder Litigation.  The Company shall give Parent
 the opportunity to participate, on an advisory basis, in the defense of any
 stockholder litigation against the Company and/or its directors relating to
 the transactions contemplated by this Agreement or the Option Agreement.

      Section 5.15   Rights Agreement.  The Board of Directors of the
 Company shall take all further action (in addition to that referred to in
 Section 3.1(x) hereof) requested in writing by Parent in order to render
 the rights (the "Rights") issued pursuant to the Rights Agreement
 inapplicable to the Merger and the other transactions contemplated by this
 Agreement and the Option Agreement.

      Section 5.16   Conveyance Taxes.  The Company and the Parent shall
 cooperate in the preparation, execution and filing of all returns,
 questionnaires, applications or other documents regarding any real property
 transfer or gains, sales, use, transfer, value added, stock transfer and
 stamp taxes, any transfer, recording, registration and other fees, and any
 similar taxes which become payable in connection with the transaction
 contemplated by this Agreement that are required or permitted to be filed
 on or before the Effective Time.


                                 ARTICLE VI
                            CONDITIONS PRECEDENT

      Section 6.1    Conditions to Each Party's Obligation to Effect the
 Merger.  The respective obligation of each party to effect the Merger is
 subject to the satisfaction or waiver on or prior to the Closing Date of
 the following conditions:

            (a)     Stockholder Approval.  The Stockholder Approval shall
 have been obtained.

            (b)     Nasdaq Listing.  The shares of Parent Company Stock
 issuable to the Company's stockholders as contemplated by this Agreement
 shall have been approved for listing on Nasdaq, subject to official notice
 of issuance.

            (c)     HSR Act.  The waiting period (and any extension
 thereof) applicable to the Merger under the HSR Act shall have been
 terminated or shall have expired.

            (d)     No Injunctions or Restraints.  No temporary restraining
 order, preliminary or permanent injunction or other judgment or order
 issued by any court of competent jurisdiction or other statute, law, rule,
 legal restraint or prohibition (collectively, "Restraints") shall be in
 effect preventing the consummation of the Merger; provided, however, that
 each of the parties that have used its reasonable best efforts to prevent
 the entry of any such Restraints and to appeal as promptly as possible any
 such Restraints that may be entered.

            (e)     Form S-4.  The Form S-4 shall have become effective
 under the Securities Act and shall not be the subject of any stop order or
 proceedings seeking a stop order.

            (f)     Pooling Letters.  Parent and the Company shall have
 received letters from Ernst & Young LLP and PricewaterhouseCoopers LLP,
 dated as of the Closing Date, in each case, addressed to Parent and the
 Company, stating in substance the matters to be stated by Ernst & Young LLP
 and PricewaterhouseCoopers LLP, pursuant to Section 5.2(b) and Section
 5.3(b), respectively.

            (g)     No Governmental Litigation.  There shall not be pending
 any suit, action or proceeding by any Governmental Entity, (i) challenging
 the acquisition by Parent or Sub of any shares of Company Common Stock,
 seeking to restrain or prohibit the consummation of the Merger, or seeking
 to place limitations on the ownership of shares of Company Common Stock (or
 shares of common stock of the Surviving Corporation) by Parent or Sub or
 seeking to obtain from the Company, Parent or Sub any damages that are
 material in relation to the Company, (ii) seeking to prohibit or materially
 limit the ownership or operation by the Company or its Subsidiaries, Parent
 or any of Parent's Subsidiaries of any material portion of any business or
 of any assets of the Company, Parent or any of Parent's Subsidiaries, or to
 compel the Company, Parent or any of Parent's Subsidiaries to divest or
 hold separate any material portion of any business or of any assets of the
 Company, Parent or any of their respective Subsidiaries, as a result of the
 Merger or (iii) seeking to prohibit Parent or any of its Subsidiaries from
 effectively controlling in any material respect the business or operations
 of the Company or its Subsidiaries.

      Section 6.2    Conditions to Obligations of Parent and Sub.  The
 obligations of Parent and Sub to effect the Merger are further subject to
 the satisfaction or waiver on or prior to the Closing Date of the following
 conditions:

            (a)     Representations and Warranties.  Each representation
 and warranty of the Company contained in this Agreement that is qualified
 as to materiality shall be true and correct, and each representation and
 warranty of the Company contained in this Agreement that is not so
 qualified shall be true and correct in all material respects, in each case
 as of the date of this Agreement and as of the Closing Date as though made
 on the Closing Date, except to the extent such representations and
 warranties expressly relate to an earlier date, in which case as of such
 earlier date.  Parent shall have received a certificate signed on behalf of
 the Company by the chief executive officer and the chief financial officer
 of the Company to such effect.

            (b)     Performance of Obligations of the Company.  The Company
 shall have performed in all material respects all obligations required to
 be performed by it under this Agreement at or prior to the Closing Date,
 and Parent shall have received a certificate signed on behalf of the
 Company by the chief executive officer and the chief financial officer of
 the Company to such effect.

            (c)     Letters from Company Affiliates.  Parent shall have
 received from each Person named in the letter referred to in Section
 5.10(a) an executed copy of an agreement substantially in the form of
 Exhibit A hereto.

            (d)     No Material Adverse Effect.  No fact or development
 shall have occurred and be continuing which has had or would be reasonably
 likely to result in any change, effect, event, occurrence or state of facts
 (or any development that has had or is reasonably likely to have any change
 or effect) that is materially adverse to the business, financial condition
 or results of operations of the Company and its Subsidiaries, taken as a
 whole.

            (e)     Consents.  All consents, the absence of which, in the
 aggregate, would be reasonably likely to have a Material Adverse Effect,
 shall have been obtained.

            (f)     Environmental Laws.  Any consents and authorizations
 required under any Environmental Law for the operation of the Surviving
 Corporation after the Closing shall have been obtained.

      Section 6.3    Conditions to Obligation of the Company.  The
 obligation of the Company to effect the Merger is further subject to the
 satisfaction or waiver on or prior to the Closing Date of the following
 conditions:

            (a)     Representations and Warranties.  Each representation
 and warranty of Parent and Sub contained in this Agreement that is
 qualified as to materiality shall be true and correct, and each

 representation and warranty of Parent and Sub contained in this Agreement
 that is not so qualified shall be true and correct in all material
 respects, in each case as of the date of this Agreement and as of the
 Closing Date as though made on the Closing Date, except to the extent such
 representations and warranties expressly relate to an earlier date, in
 which case as of such earlier date.  The Company shall have received a
 certificate signed on behalf of Parent by an executive officer of Parent to
 such effect.

            (b)     Performance of Obligations of Parent and Sub.  Parent
 and Sub shall have performed in all material respects all obligations
 required to be performed by them under this Agreement at or prior to the
 Closing Date, and the Company shall have received a certificate signed on
 behalf of Parent by an executive officer of Parent to such effect.

            (c)     No Material Adverse Effect.  No fact or development
 shall have occurred and be continuing which has had or would be reasonably
 likely to result in any change, effect, event, occurrence or state of facts
 (or any development that has had or is reasonably likely to have any change
 or effect) that is materially adverse to the business, financial condition
 or results of operations of Parent and its Subsidiaries, taken as a whole.

            (d)     Tax Opinion.  The Company shall have received an
 opinion of Skadden, Arps, Slate, Meagher & Flom LLP, special tax counsel to
 the Company, dated as of the Effective Time, to the effect that the Merger
 will qualify as a reorganization within the meaning of Section 368(a) of
 the Code.  The issuance of such opinion shall be conditioned upon the
 receipt by such special tax counsel of customary representation letters
 from each of Parent, Sub, and the Company, in each case, in form and
 substance reasonably satisfactory to such special tax counsel.  Each such
 representation letter shall be dated on or before the date of such opinion
 and shall not have been withdrawn or modified in any material respect.  The
 Company may not waive or amend this condition without the express written
 consent of Parent.

      Section 6.4    Frustration of Closing Conditions.  None of the
 Company, Parent or Sub may rely on the failure of any condition set forth
 in Section 6.1, Section 6.2 or Section 6.3 as the case may be, to be
 satisfied if such failure was caused by such party's failure to use
 reasonable best efforts to consummate the Merger and the other transactions
 contemplated by this Agreement and the Option Agreement, as required by and
 subject to Section 5.5.


                                 ARTICLE VII
                      TERMINATION, AMENDMENT AND WAIVER

      Section 7.1    Termination.  This Agreement may be terminated at any
 time prior to the Effective Time, whether before or after the Stockholder
 Approval:

            (a)     by mutual written consent of Parent, Sub and the
 Company;

            (b)     by either Parent or the Company:

                (i)  if the Merger shall not have been consummated by March
      31, 2000 for any reason; provided, however, that the right to
      terminate this Agreement under this Section 7.1(b)(i) shall not be
      available to any party whose action or failure to act has been a
      principal cause of or resulted in the failure of the Merger to be
      consummated on or before such date;

                (ii)  if any Restraint having any of the effects set forth
      in Section 6.1(d) shall be in effect and shall have become final and
      nonappealable; provided that the party seeking to terminate this
      Agreement pursuant to this Section 7.1(b)(ii) shall have used
      reasonable best efforts to prevent the entry of and to remove such
      Restraint; or

                (iii)  if the Stockholder Approval shall not have been
      obtained at the Stockholders Meeting duly convened therefor or at any
      adjournment or postponement thereof;

            (c)     by the Company, if Parent shall have breached or failed
 to perform any of its representations, warranties, covenants or agreements
 set forth in this Agreement, which breach or failure to perform (A) would
 give rise to the failure of a condition set forth in Section 6.3(a) or
 Section 6.3(b), and (B) is not cured by Parent within 15 calendar days
 following receipt of written notice of such breach or failure to perform
 from the Company;

            (d)     by Parent, if the Company shall have breached or failed
 to perform any of its representations, warranties, covenants or agreements
 set forth in this Agreement, which breach or failure to perform (A) would
 give rise to the failure of a condition set forth in Section 6.3(a) or
 Section 6.3(b), and (B) is not cured by the Company within 15 calendar days
 following receipt of written notice of such breach or failure to perform
 from Parent;

            (e)     by Parent, if the directors of the Company shall have
 (i) withdrawn, modified or changed the approval or recommendation of the
 Board of Directors of the Company or any committee thereof of this
 Agreement or the Merger in a manner adverse to Parent or Sub, (ii) approved
 or recommended to the stockholders of the Company a Takeover Proposal,
 (iii) approved or recommended that the stockholders of the Company tender
 their shares of Company Common Stock into any tender offer or exchange
 offer that is a Takeover Proposal or is related thereto or (iv) indicated
 any intention to do any of the foregoing; or

            (f)     by the Company in accordance with Section 4.2(b).

            (g)     by the Company as set forth in Section 2.1(e) unless
 Parent shall have delivered a Top-Up Notice as contemplated by such
 Section.

      Section 7.2    Effect of Termination.  In the event of termination of
 this Agreement by either the Company or Parent as provided in Section 7.1,
 this Agreement shall forthwith become void and have no effect, without any
 liability or obligation on the part of Parent, Sub or the Company, other
 than the provisions of Section 3.1(t)[brokers], the penultimate sentence of
 Section 5.4(a) [Parent to keep confidential nonpublic information received
 from the Company], the last sentence of Section 5.4(b) [Company to keep
 confidential nonpublic information received from Parent] and Section 5.8
 [fees and expenses], this Section 7.2 and ARTICLE VIII, which provisions
 shall survive such termination, and except to the extent that such
 termination results from the willful or material breach by a party of any
 of its representations, warranties, covenants or agreements set forth in
 this Agreement.

      Section 7.3    Amendment.  This Agreement may be amended by the
 parties hereto at any time before or after the Stockholder Approval;
 provided, however, that after any such approval, there shall be made no
 amendment that by law requires further approval by the stockholders of the
 Company without such approval.  This Agreement may not be amended except by
 an instrument in writing signed on behalf of each of the parties hereto.

      Section 7.4    Extension; Waiver.  At any time prior to the Effective
 Time, the parties may (a) extend the time for the performance of any of the
 obligations or other acts of the other parties, (b) waive any inaccuracies
 in the representations and warranties contained herein or in any document
 delivered pursuant hereto or (c) subject to the proviso of Section 7.3,
 waive compliance with any of the agreements or conditions contained herein.
 Any agreement on the part of a party to any such extension or waiver shall
 be valid only if set forth in an instrument in writing signed on behalf of
 such party.  The failure of any party to this Agreement to assert any of
 its rights under this Agreement or otherwise shall not constitute a waiver
 of such rights.


                                ARTICLE VIII
                             GENERAL PROVISIONS

      Section 8.1    Nonsurvival of Representations and Warranties.  None of
 the representations and warranties in this Agreement or in any instrument
 delivered pursuant to this Agreement shall survive the Effective Time.
 This Section 8.01 shall not limit any covenant or agreement of the parties
 which by its terms contemplates performance after the Effective Time.

      Section 8.2    Notices.  All notices, requests, claims, demands and
 other communications hereunder shall be in writing and shall be deemed
 given, and shall be effective upon receipt, if delivered personally,
 telecopied (which is confirmed) or sent by overnight courier (providing
 proof of delivery) to the parties at the following addresses (or at such
 other address for a party as shall be specified by like notice):

            if to Parent or Sub, to:

            MedImmune, Inc.
            35 West Watkins Mill Road
            Gaithersburg, Maryland  20878
            Telephone: (301) 417-0770
            Telecopier: (301) 527-4200

            with a copy to:

            Dewey Ballantine LLP
            1301 Avenue of the Americas
            New York, New York 10019-6092
            Telephone: (212) 259-8000
            Telecopier: (212) 259-6333
            Attention: Frederick W. Kanner

            if to the Company, to:

            U.S. Bioscience, Inc.
            One Tower Bridge
            100 Front Street, Suite 400
            West Conshohocken, Pennsylvania  19428
            Telephone: (800) 898-4404
            Telecopier: (610) 832-4500

            with a copy to:

            Skadden, Arps, Slate Meagher & Flom LLP
            919 Third Avenue
            New York, New York 10022-3897
            Telephone: (212) 735-3000
            Telecopier: (212) 735-2000
            Attention:  Margaret L. Wolff

      Section 8.3    Definitions.  For purposes of this Agreement:

            (a)     an "Affiliate" of any Person means another Person that
 directly or indirectly, through one or more intermediaries, controls, is
 controlled by, or is under common control with, such first Person;

            (b)     "Business Day" means any day other than Saturday,
 Sunday or any other day on which banks are legally permitted to be closed
 in New York;

            (c)     "Knowledge" of any Person that is not an individual
 means, with respect to any matter in question, the actual knowledge of any
 of such person's executive officers or other employees having primary
 responsibility for such matter;

            (d)     "Material Adverse Change" or "Material Adverse Effect",
 as used with respect to the Company or Parent, as the case may be, means
 any change, effect, event, occurrence or state of facts (or any development
 that has had or is reasonably likely to have any change or effect) that is
 materially adverse to the business, financial condition or results of
 operations of such entity and its Subsidiaries, taken as a whole, or which
 would prevent or materially delay the consummation of the transactions
 contemplated hereby;

            (e)     "Person" means an individual, corporation, partnership,
 limited liability company, joint venture, association, trust,
 unincorporated organization or other entity;

            (f)     a "Subsidiary" of any Person means, with respect to
 such Person, any corporation, partnership, joint venture or other legal
 entity of which such person (either alone or through or together with any
 other subsidiary), owns, directly or indirectly, 50% or more of the stock
 or other equity interests the holders of which are generally entitled to
 vote for the election of the Board of Directors or other governing body of
 such corporation or other legal entity;

            (g)     "Superior Proposal" means any bona fide proposal made
 by a third party (i) to acquire, directly or indirectly, including pursuant
 to a tender offer, exchange offer, merger, consolidation, business
 combination, recapitalization, liquidation, dissolution or similar
 transaction, for consideration consisting of cash and/or securities, more
 than 50% of the combined voting power of the shares of Company Common Stock
 then outstanding or all or substantially all the assets of the Company and
 its Subsidiaries taken as a whole, (ii) that is otherwise on terms which
 the Board of Directors of the Company determines in its good faith judgment
 (based on advice from a financial advisor of nationally recognized
 reputation) to be more favorable to the Company and its stockholders than
 the Merger after taking into account the terms of this Agreement (as it may
 be proposed to be amended by Parent), (iii) which is reasonably capable of
 being consummated on a prompt basis, (iv) for which financing, to the
 extent required, is then committed or which, in the good faith judgment of
 the Board of Directors of the Company, is reasonably capable of being
 obtained by such third party and (v) for which no regulatory approvals,
 including antitrust approvals, are required that are not reasonably be
 expected to be obtained on prompt basis; and

            (h)     "Takeover Proposal" means any bona fide inquiry,
 proposal or offer from any Person relating to any direct or indirect
 acquisition or purchase of a business or assets that constitute 15% or more
 of the net revenues, net income or the assets of the Company or its
 Subsidiaries, taken as a whole, or 15% or more of any class of equity
 securities of the Company or its Subsidiaries or any tender offer or
 exchange offer that if consummated would result in any Person beneficially
 owning 15% or more of any class of equity securities of the Company or any
 of its Subsidiaries or any merger, consolidation, business combination,
 recapitalization, liquidation, dissolution or similar transaction involving
 the Company or any of its Subsidiaries, other than the transactions
 contemplated by this Agreement.

      Section 8.4    Interpretation.  When a reference is made in this
 Agreement to an Article, a Section, Exhibit or Schedule, such reference
 shall be to an Article of, a Section of, or an Exhibit or Schedule to, this
 Agreement unless otherwise indicated.  The table of contents and headings
 contained in this Agreement are for reference purposes only and shall not
 affect in any way the meaning or interpretation of this Agreement.
 Whenever the words "include", "includes" or "including" are used in this
 Agreement, they shall be deemed to be followed by the words "without
 limitation".  The words "hereof", "herein" and "hereunder" and words of
 similar import when used in this Agreement shall refer to this Agreement as
 a whole and not to any particular provision of this Agreement.  All terms
 defined in this Agreement shall have the defined meanings when used in any
 certificate or other document made or delivered pursuant hereto unless
 otherwise defined therein.  The definitions contained in this Agreement are
 applicable to the singular as well as the plural forms of such terms and to
 the masculine as well as to the feminine and neuter genders of such term.
 Any agreement, instrument or statute defined or referred to herein or in
 any agreement or instrument that is referred to herein means such
 agreement, instrument or statute as from time to time amended, modified or
 supplemented, including (in the case of agreements or instruments) by
 waiver or consent and (in the case of statutes) by succession of comparable
 successor statutes and references to all attachments thereto and
 instruments incorporated therein.  References to a Person are also to its
 permitted successors and assigns.

      Section 8.5    Counterparts.  This Agreement may be executed in one or
 more counterparts, all of which shall be considered one and the same
 agreement and shall become effective when two or more counterparts have
 been signed by each of the parties and delivered to the other parties.

      Section 8.6    Entire Agreement; Third-Party Beneficiaries.  This
 Agreement, the Option Agreement and the Confidentiality Agreement (a)
 constitute the entire agreement, and supersede all prior agreements and
 understandings, both written and oral, among the parties with respect to
 the subject matter of this Agreement, the Option Agreement and the
 Confidentiality Agreement and (b) except for the provisions of Section 5.7,
 are not intended to confer upon any Person other than the parties any
 rights or remedies.

      Section 8.7    Governing Law.  This Agreement shall be governed by,
 and construed in accordance with, the laws of the State of Delaware,
 regardless of the laws that might otherwise govern under applicable
 principles of conflicts of laws thereof.

      Section 8.8    Assignment.  Neither this Agreement nor any of the
 rights, interests or obligations hereunder shall be assigned, in whole or
 in part, by operation of law or otherwise by any of the parties without the
 prior written consent of the other parties, except that Sub may assign, in
 its sole discretion, any of or all its rights, interests and obligations
 under this Agreement to Parent or to any direct or indirect wholly owned
 Subsidiary of Parent, but no such assignment shall relieve Sub of any of
 its obligations hereunder.  Subject to the preceding sentence, this
 Agreement will be binding upon, inure to the benefit of, and be enforceable
 by, the parties and their respective successors and assigns.

      Section 8.9    Enforcement.  The parties agree that irreparable damage
 would occur and that the parties would not have any adequate remedy at law
 in the event that any of the provisions of this Agreement were not
 performed in accordance with their specific terms or were otherwise
 breached.  It is accordingly agreed that the parties shall be entitled to
 an injunction or injunctions to prevent breaches of this Agreement and to
 enforce specifically the terms and provisions of this Agreement in any
 Federal court located in the State of Delaware or in any state court in the
 State of Delaware, this being in addition to any other remedy to which they
 are entitled at law or in equity.  In addition, each of the parties hereto
 (a) consents to submit itself to the personal jurisdiction of any Federal
 court located in the State of Delaware or of any state court located in the
 State of Delaware in the event any dispute arises out of this Agreement or
 the transactions contemplated by this Agreement, (b) agrees that it will
 not attempt to deny or defeat such personal jurisdiction by motion or other
 request for leave from any such court and (c) agrees that it will not bring
 any action relating to this Agreement or the transactions contemplated by
 this Agreement in any court other than a Federal court located in the State
 of Delaware or a state court located in the State of Delaware.

      Section 8.10   Severability.  If any term or other provision of this
 Agreement is invalid, illegal or incapable of being enforced by any rule of
 law or public policy, all other conditions and provisions of this Agreement
 shall nevertheless remain in full force and effect.  Upon such
 determination that any term other provision is invalid, illegal or
 incapable of being enforced, the parties hereto shall negotiate in good
 faith to modify this Agreement so as to effect the original intent of the
 parties as closely as possible to the fullest extent permitted by
 applicable law in an acceptable manner to the end that the transactions
 contemplated hereby are fulfilled to the extent possible.

      IN WITNESS WHEREOF, Parent, Sub and the Company have caused this
 Agreement to be signed by their respective officers thereunto duly
 authorized, all as of the date first written above.


                               MEDIMMUNE, INC.


                               By: /s/ Wayne T. Hockmeyer
                                   -------------------------------------------
                                   Name: Wayne T. Hockmeyer
                                   Title: Chairman and Chief Executive Officer


                               MARLIN MERGER SUB INC.


                               By: /s/ Wayne T. Hockmeyer
                                   -------------------------------------------
                                   Name: Wayne T. Hockmeyer
                                   Title: Chairman and Chief Executive Officer


                               U.S. BIOSCIENCE, INC.


                               By: /s/ C. Boyd Clarke
                                   --------------------------------------------
                                   Name: C. Boyd Clarke
                                   Title: President and Chief Executive Officer