<PAGE>

                                                                    Exhibit 10.1

                                    AGREEMENT

              This Agreement (this "Agreement") is made as of December 12, 2001,
among Bioject Medical Technologies Inc., an Oregon corporation (the "Company"),
Elan Pharmaceutical Investments, Ltd. ("EPIL") and Elan International Services,
Ltd. ("EIS" and together with EPIL, "Elan").

              WHEREAS, the Company and Elan are parties to that certain
Securities Purchase Agreement dated as of October 15, 1997 (as amended by the
Amendment to Securities Purchase Agreement dated January 15, 1998 by the Company
and EIS, the Agreement to Amend Securities Purchase Agreement and Certain
Related Securities dated June 30, 1999 among the Company, EIS and Marathon
Medical Technologies, Inc. (the "1999 Amendment") and the Agreement by the
Company and EIS dated May, 2000, all of which are attached as Annex I and
referred to collectively in this Agreement as the "Purchase Agreement"),
relating to the issuance and sale to Elan of the Securities subject to the terms
of the relevant Transaction Documents (as modified, amended or supplemented to
the date hereof, the "Existing Transaction Documents"). Capitalized terms used
in this Agreement without definition shall have the meanings given such terms in
the Purchase Agreement.

              WHEREAS, EIS has previously assigned to EPIL all of its interests
in the Securities after the date of issuance thereof; and

              WHEREAS, the Company and Elan have agreed to amend certain of the
Existing Transaction Documents and make certain agreements with respect to the
Securities held by Elan from time to time.

              NOW, THEREFORE, in consideration of the premises set forth herein
and for other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, each of the undersigned hereby agrees as follows:

              1. Amendments to Transaction Documents.

                     (a) Article IV, Section 2.3(a)(1) of the Amended and
       Restated Articles of Incorporation of Bioject Medical Technologies Inc.,
       as in effect on the date hereof (the "Articles of Incorporation"
       (attached hereto as Annex II)) shall be deemed by the parties hereto to
       be deleted in its entirety as of the Effective Date (as defined in
       Section 4 below) and replaced with the following language:

              "Each outstanding share of Series A Preferred Stock shall accrue
              from the date of issuance through October 15, 2001 a dividend
              equal to 9%


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                                      -2-

              per annum of the Preferred Issuance Price of Series A Preferred
              Stock, compounded semiannually beginning on September 2, 1998;
              such dividend shall be paid by the issuance of additional shares
              of Series A Preferred Stock, based upon a value equal to the
              Preferred Issuance Price."

                     (b) Article IV, Sections 2.6(a)(1) and (3) of the Articles
       of Incorporation shall be deemed by the parties hereto to be deleted in
       their entirety and of no further force or effect whatsoever as of the
       Effective Date.

                     (c) Article IV, Section 2.6(a)(2) of the Articles of
       Incorporation shall be deemed by the parties hereto to be deleted in its
       entirety as of the Effective Date and renumbered as Section 2.6(a) and
       replaced with the following language:

              "Series A Preferred Stock. All holders of Series A Preferred Stock
              issued as of December 12, 2001, shall have the right to convert at
              any time each share of Series A Preferred Stock into two shares of
              Common Stock as of such date (which amount gives effect to the
              Reverse Stock Split described in Section 1.1), subject to Section
              2.6(e) below (the "Antidilution Adjustments")."

                     (d) Article IV, Section 2.6(c)(1) of the Articles of
       Incorporation shall be deemed by the parties hereto to be deleted in its
       entirety and of no further force or effect whatsoever as of the Effective
       Date.

                     (e) Article IV, Section 2.6(c)(2) of the Articles of
       Incorporation shall be deemed by the parties hereto to be deleted in its
       entirety as of the Effective Date and renumbered as Section 2.6(c) and
       replaced with the following language:

              "Series C Preferred Stock. All holders of Series C Preferred Stock
              issued as of December 12, 2001 shall have the right to convert at
              any time each share of Series C Preferred Stock into two shares of
              Common Stock as of such date (which amount gives effect to the
              Reverse Stock Split described in Section 1.1), subject to the
              Antidilution Adjustments."

                     (f) Article IV, Sections 2.7(a) and (c) of the Articles of
       Incorporation shall be deemed by the parties hereto to be deleted in
       their entirety and of no further force or effect whatsoever as of the
       Effective Date.


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                                      -3-

                     (g) Section 5(c) of the Purchase Agreement is hereby
       deleted in its entirety and of no further force or effect whatsoever as
       of the Effective Date.

                     (h) Pursuant to Section 8(a) of the Series "K" Warrant to
       Purchase Shares of Common Stock originally issued by the Company to Elan
       International Services, Ltd. in connection with the Purchase Agreement
       (the "Series K Warrant"), a copy of which is attached as Annex III, the
       Series K Warrant is hereby terminated and is of no further force or
       effect whatsoever.

                     (i) Section 1 of the Series "P" Common Stock Purchase
       Warrant of the Company originally issued by the Company to EIS, pursuant
       to the 1999 Amendment (the "Series P Warrant"), a copy of which is
       attached as Annex IV, is hereby amended as of the Effective Date by
       adding the following language after the first sentence thereof:

              "Notwithstanding the foregoing, the holder hereof shall exercise
              this Warrant (by payment of the applicable Exercise Price (in cash
              or by cancellation of indebtedness of the Corporation to the
              holder hereof as provided in Section 2 of this Warrant)), (i) on
              the Effective Date (as defined in the Agreement among the Company
              and Elan Pharmaceutical Investments, Ltd. and Elan International
              Services, Ltd. dated December 12, 2001 (the "Agreement")) for
              252,666 shares of the Warrant Stock, (ii) within 30 days of the
              holder's receipt of written notice from the Corporation that on
              the first anniversary of the Effective Date the Market Price (as
              defined below) of common stock of the Corporation (the "Common
              Stock") was at least $12.50 per share (such notice to include
              evidence reasonably satisfactory to the holder hereof as to the
              basis for the calculation of such price and to be given no later
              than the fifth business day following such anniversary and in such
              manner as is specified in Section 9 of the Agreement), for 252,667
              shares of the Warrant Stock and (iii) within 30 days of the
              holder's receipt of written notice from the Corporation that on
              the second anniversary of the Effective Date the Market Price of
              the Common Stock was at least $15.00 per share (such notice to
              include evidence reasonably satisfactory to the holder hereof as
              to the basis for the calculation of such price and to be given no
              later than the fifth business day following such anniversary and
              in such manner as is specified in Section 9 of the Agreement), for
              the remaining Warrant Stock not previously purchased pursuant to
              an exercise of this Warrant; provided, however, the holder hereof
              is not obligated to make any such exercise unless at such time at
              least one or more registration statements is then effective
              pursuant to which all the


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                                      -4-

              Warrant Stock issued or issuable upon exercise hereof may be
              publicly sold by such holder under the Securities Act of 1933, as
              amended; provided, further, however, that notwithstanding the
              foregoing provisions of this sentence, the holder of this Warrant
              retains the right to exercise this Warrant at any time pursuant to
              the first sentence of this Section 1. In the event that the holder
              hereof has not exercised this Warrant for all Warrant Stock as of
              the close of business on the later of (x) the fifth business day
              after the second anniversary of the Effective Date if no notice
              pursuant to clause (iii) above has been delivered to the holder
              hereof on or before such date or (y) the 30th day following
              receipt by the holder hereof of any notice pursuant to clause
              (iii) above, as a result of the failure of the conditions set
              forth in the immediately preceding sentence, then thereafter the
              provisions of such sentence shall terminate and have no further
              force or effect. All share amounts and prices per share in this
              Section 1 shall be subject to appropriate adjustment from time to
              time pursuant to Section 11 of this Warrant.

              "Market Price" means, with respect to each anniversary of the
              Effective Date requiring a calculation thereof as provided above,
              the average of the daily Closing Prices (as defined below) per
              share of the Common Stock for the 10 consecutive trading days
              ending on the trading day immediately preceding such anniversary;
              provided, however, that in the event that the Market Price is
              determined during a period following the announcement by the
              Corporation of (A) a dividend or distribution of Common Stock, or
              (B) any subdivision, combination or reclassification of Common
              Stock and prior to the expiration of 20 business days after the
              ex-dividend date for such dividend or distribution, or the record
              date for such subdivision, combination or reclassification, then,
              and in each such case, the Market Price shall be appropriately
              adjusted to reflect the current market price per share equivalent
              of the Common Stock. "Closing Price" means the reported last sales
              price regular way or, if no such reported sale occurs on such day,
              the average of the closing bid and asked prices regular way on
              such day, in each case as reported by NASDAQ or such other
              principal consolidated transaction reporting system with respect
              to securities listed on the principal national securities exchange
              on which the Common Stock is listed or admitted to trading, or any
              comparable system then in use or, if not so reported, as reported
              by any New York Stock Exchange member firm reasonably selected by
              the holder of this Warrant for purposes of estab-


<PAGE>

                                      -5-

              lishing whether this Warrant must be exercised pursuant to the
              second sentence of this Section 1."

                     (j) Section 6 of the Series P Warrant is hereby deleted in
       its entirety and of no further force or effect as of the Effective Date.

              2. Resale of Common Stock; Etc.

                     (a) Elan hereby agrees to sell, in one transaction or a
       series of related or unrelated transactions, the 545,455 shares of Common
       Stock originally acquired under the Purchase Agreement and the 252,666
       shares of Common Stock to be acquired by Elan on the Effective Date upon
       the exercise of the Series P Warrant pursuant to Section 1(i) of this
       Agreement (the "Original Shares") to one or more individuals,
       partnerships, corporations, limited liability companies or other entities
       not affiliates of Elan (any such entity, a "Non-Affiliate") on or before
       March 31, 2002; provided, (A)(i) on or before January 8, 2002, Elan may
       contract to sell such shares in any such transaction (for any or all of
       the Original Shares) in a manner and at such time as Elan may determine
       and (ii) on and after January 9, 2002 through and including March 31,
       2002, Elan shall contract to sell such shares in any such transaction
       with respect to such Original Shares not sold pursuant to the foregoing
       clause (i) exclusively through Leerink Swann & Company under the same
       terms and conditions as sales of Common Stock by the Company, on a pro
       rata basis (determined by reference to the number of Original Shares not
       sold (or contracted to be sold) pursuant to the foregoing clause (i) and
       the number of shares of Common Stock the Company identifies to Leerink
       Swann & Company for sale during such period) and (B) in any one such
       transaction the consideration Elan receives per Original Share (subject
       to adjustment to reflect any subdivision or combination of the Common
       Stock on or before the date of any such transaction, including the
       Reverse Stock Split (as defined in the Articles of Incorporation) shall
       be no less than $10.25 per share, net of any commissions, fees or
       discounts charged in connection with such transaction; provided, that,
       except with respect to any transaction contemplated by clause (A)(ii) of
       the first proviso of this Section 2(a), Elan shall not be obligated to
       make any such sale pursuant to this Section 2(a) unless at such time at
       least one or more registration statements is then effective pursuant to
       which the Original Shares may be publicly sold by Elan under the
       Securities Act of 1933, as amended (the "Securities Act"); provided,
       further, if on or before March 31, 2002 Elan has not disposed of all of
       its Original Shares pursuant to this Section 2(a) as a result of the
       failure of the conditions hereof to be satisfied, then the provisions of
       this Section 2(a) shall terminate as of the close of business on such
       date and Elan shall have no further obligations under this Section 2(a).


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                                      -6-

                     (b) The parties hereto hereby agree that, after the earlier
       of March 31, 2002 or the sale of all of the Original Shares as
       contemplated by Section 2(a) of this Agreement, Elan may sell any shares
       of Common Stock, including shares of Common Stock acquired upon
       conversion of the Series A Preferred Stock or the Series C Preferred
       Stock or upon exercise of the Series P Warrant after the Effective Date,
       and any shares of the Series A Preferred Stock or Series C Preferred
       Stock, and any Series P Warrants, in each case in a manner and at such
       time as Elan may determine, subject to any holdback agreements
       contemplated by the Registration Rights Agreement and any applicable
       securities law restrictions.

                     (c) The parties hereto agree that notwithstanding the
       provisions of any Existing Transaction Document, Elan is not subject to
       any provisions of any Existing Transaction Document limiting or
       restricting its ability to sell any of the Securities (other than any
       holdback agreements contemplated by the Registration Rights Agreement),
       including the Original Shares and any Common Stock acquired upon exercise
       of the Series P Warrant or conversion of the Series A Preferred Stock or
       Series C Preferred Stock, at any time or in any manner, other than any
       applicable restrictions under the Securities Act.

              3. Waivers.

                     (a) The Company hereby waives as of the Effective Date any
       rights it had prior to the date hereof solely with respect to those
       provisions of the Articles of Incorporation deemed to be amended or
       deleted pursuant to Sections 1(a) through (f) hereof (the "Amendments to
       the Articles"), including any right to redeem the Series A Preferred
       Stock and hereby rescinds any action heretofore undertaken in any manner
       or to any extent to exercise any such right, and waives any right it
       would have hereafter under such provisions whether or not the Amendments
       to the Articles are approved by the Company's shareholders.

                     (b) Elan hereby waives any rights as a holder of the Series
       A Preferred Stock or Series C Preferred Stock it had prior to the date
       hereof solely with respect to those provisions deemed to be amended or
       deleted by the Amendments to the Articles and waives any right it would
       have hereafter under such provisions whether or not the Amendments to the
       Articles are approved by the Company's shareholders.

              4. Conditions. This Agreement shall become effective upon the date
       (the "Effective Date") that


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                                      -7-

                     (a) all of the following, duly executed, have been
       delivered to Elan:

                            (i) this Agreement;

                            (ii) Certificates for 260,044 shares of Series A
              Preferred Stock, which the parties agree represents all dividends
              accrued on the Series A Preferred Stock from the date of first
              issuance thereof through and including October 15, 2001;

                            (iii) Certificates for the shares of Common Stock
              being acquired by Elan pursuant to the exercise of the Series P
              Warrant as contemplated by Section 1(i) of this Agreement; and

                            (iv) An opinion of counsel of the Company, in the
              form attached to this Agreement as Annex V, as to the matters set
              forth in Section 6(a) hereof;

                            (v) Supplements to the currently effective
              prospectuses to cover the sale by EPIL of the Original Shares.

                     (b) all of the following, duly executed, have been
       delivered to Bioject:

                            (i) this Agreement;

                            (ii) the cash amount of $1,894,995, representing the
              exercise price for the shares to be purchased by Elan pursuant to
              the exercise of the Series P Warrant as contemplated by Section
              1(i) of this Agreement;

                            (iii) the original Series K Warrant for
              cancellation; and

                            (iv) the cash amount of $100,000 in consideration
              for the option granted pursuant to Section 8 of this Agreement.

The parties agree to take all actions required as conditions so that the
Effective Date shall occur no later than December 14, 2001.

              5. Covenants.


<PAGE>

                                      -8-

                     (a) The Company hereby covenants that at its next regularly
       scheduled annual meeting of its shareholders it shall request and use its
       best efforts to obtain shareholder approval of the Amendments to the
       Articles; provided, Elan shall have the right to review and comment on
       the proxy material to be distributed in connection with any such annual
       meeting; provided, further, in the event that the shareholders do not
       approve the Amendments to the Articles as contemplated by this Section
       5(a) on or before the first anniversary of the Effective Date, the
       Company covenants that it will issue to Elan a warrant exercisable at a
       nominal exercise price for a number of shares of Common Stock equal in
       value (based on the Market Price thereof on such anniversary as defined
       in the Series P Warrant) on such first anniversary to the sum of (x) the
       valuation of all of the shares of Series A Preferred Stock held by Elan
       on such date (including the valuation of the conversion feature of such
       shares based on the Black-Scholes method of valuation of securities with
       option features, giving effect to the adoption of the Amendments to the
       Articles) minus the valuation of all of such shares (including the
       valuation of the conversion feature of such shares based on the
       Black-Scholes method of valuation of securities with option features,
       without giving effect to the adoption of the Amendments to the Articles)
       plus (y) 10% of the difference in valuations specified in clause (x);
       provided, the parties hereto agree that the valuation and methods
       contemplated hereby will be pursuant to such further agreements as to the
       procedures for such valuation as the parties shall mutually agree to.

                     (b) In addition to the rights and obligations of the
       parties hereto under the Registration Rights Agreement, including the
       provisions of Section 6 thereof, the Company hereby covenants that the
       Company shall use its best efforts to keep the currently effective
       registration statements of the Company effective until all shares of
       Common Stock held by Elan as of the Effective Date and all shares of
       Common Stock issuable upon conversion of the Series A Preferred Stock or
       the Series C Preferred Stock and the exercise of the Series P Warrant are
       (A) sold pursuant to an effective registration statement under the
       Securities Act, (B) eligible to be sold into the public market without
       regard to volume limitations under Rule 144(k) promulgated under the
       Securities Act (or any successor rule), or (C) sold pursuant to Rule 144.

                     (c) The Company covenants not to sue EIS, EPIL or Elan
       Corporation, plc including, as applicable, all of the direct or indirect
       stockholders, members and affiliates thereof (including, but not limited
       to, parent, subsidiary and affiliated corporations or other entities) and
       each of their respective past and present officers, directors, members,
       agents, employees, representatives, lawyers, administrators, spouses, and
       all persons acting by, through, under, or in concert


<PAGE>

                                      -9-

       with them (collectively, the "Elan Entities") with respect to any and all
       claims for damages or other sums, including attorneys' fees and costs, or
       for any other relief or remedy, which the Company may have against them,
       or any of them, which could have arisen out of any act or omission with
       respect to the Company's redemption rights that were the basis for the
       Complaint (as defined in Section 7 hereof) (each a "Complaint Related
       Claim") and covenants to indemnify and hold harmless each Elan Entity
       from and against any losses, claims, damages or liabilities (including
       actions or proceedings in respect thereof) arising out of any Complaint
       Related Claim that may be alleged by any other party.

                     (d) Elan hereby covenants to (i) use its best efforts to
       cooperate with the Company in causing the Amendments to the Articles to
       be approved, including, without limitation, voting all of its shares of
       the Company's stock in favor of the proposals relating to the Amendments
       to the Articles and (ii) notify the Company promptly after the
       consummation of each transaction contemplated by Section 2(a) of this
       Agreement.

              6. Representations and Warranties.

                     (a) The Company represents and warrants to Elan that (i)
       attached hereto as Annex II is a true and complete copy of the Articles
       of Incorporation; (ii) the Company is a corporation duly organized and
       validly existing under the laws of Oregon, with all corporate power and
       authority necessary to execute, deliver and perform its obligations under
       this Agreement; (iii) the execution, delivery and performance by the
       Company of this Agreement has been duly authorized by all necessary
       action and this Agreement constitutes the legal, valid and binding
       obligation of the Company, enforceable against the Company in accordance
       with its terms; and (iv) as of the Effective Date the registration
       statements covering the sale of the shares of Common Stock held by Elan
       have been declared effective under the Securities Act by the Securities
       and Exchange Commission and have not been withdrawn by the Company and to
       the Company's knowledge no stop order proceedings with respect thereto
       are pending or threatened under the Securities Act.

                     (b) Elan represents and warrants to the Company that (i)
       Elan now has good and marketable title to all of the shares of Preferred
       Stock and Common Stock of the Company issued to Elan pursuant to the
       Purchase Agreement, the Series K Warrant and the Series P Warrant, free
       and clear of any liens, encumbrances and claims, and full right, power
       and authority to effect the sale and delivery of such securities; (ii)
       each of the Elan entities is a corporation duly organized and validly
       existing under the laws of its incorporation, with all corpo-


<PAGE>

                                      -10-

       rate power and authority necessary to execute, deliver and perform its
       obligations under this Agreement; (iii) the execution, delivery and
       performance by Elan of this Agreement has been duly authorized by all
       necessary action and this Agreement constitutes the legal, valid and
       binding obligation of Elan, enforceable against Elan in accordance with
       its terms.

              7. Dismissal of the Complaint. Within 2 business days after the
Effective Date, the Company and all those under its control shall, in the form
attached hereto as Annex VI, arrange for the dismissal of the lawsuit entitled
Bioject Medical Technologies Inc. v. Elan Corporation, plc, et. al, Case
No.01-CV-1438-AS, filed in the United States District Court for the Federal
District of Oregon (the "Complaint"). The Company shall promptly provide
evidence of such dismissal to Elan. By entering into this Agreement no party is
making any admission of liability, nor admitting the sufficiency of any other
party's allegations in the Complaint. Instead, the parties hereto have entered
into this Agreement to compromise disputed claims and to avoid the further
expense and burden of litigation. No party admits liability, wrongdoing, or any
sort of malfeasance.

              8. License Agreement Option. In separate consideration of the
payment of the sum of $100,000 simultaneously with the execution of this
Agreement, the Company grants to EIS an option, but not the obligation,
exercisable on or prior to the six-month anniversary of the Effective Date to
obtain a license of the Company's Iject product for any one drug of Elan or of a
joint venture partner of Elan, the form and substance of which license agreement
shall be negotiated in good faith by the parties hereto.

              9. Notice. All notices, demands and requests of any kind to be
delivered to any party in connection with this Agreement shall be in writing and
shall be deemed to have been duly given if personally delivered or when sent if
sent by nationally-recognized overnight courier or by registered or certified
airmail, return receipt and postage prepaid, or by facsimile transmission,
addressed as follows:

              If to the Company:

              Bioject Medical Technologies, Inc.
              7620 S.W. Bridgeport Road
              Portland, Oregon 97224
              Fax: (503) 620-6431
              Attention: James C. O'Shea


<PAGE>

                                      -11-

              With a copy to:

              Stoel Rives LLP
              900 SW Fifth Avenue, Suite 2600
              Portland, Oregon  97204
              Fax: 503-220-2480
              Attention: Todd Bauman

              If to EPIL or EIS:

              c/o Elan Pharmaceutical Investments, Ltd.
              102 St. James Court
              Flatts Smiths FL04, Bermuda
              Fax: (441)292-2224
              Attention: Kevin Insley

              With a copy to:

              Cahill Gordon & Reindel
              80 Pine Street
              New York, NY 10005
              Fax: (212)269-5420
              Attention: William Hartnett

              10. Specific Performance, Etc. The parties hereto agree that
irreparable damage would occur in the event any provision of this Agreement were
not performed in accordance with the terms hereof and that the parties shall be
entitled to specific performance of the terms hereof, in addition to any other
remedy at law or in equity.

              11. Expenses. Each party hereto shall be responsible for payment
of its own attorneys' fees, costs, and other legal expenses incurred through the
date of this Agreement.

              12. Confidentiality; Non-Disclosure.

                     (a) Subject to clause (b) below, from and after the date
       hereof, neither the Company, EIS nor EPIL (nor their respective
       affiliates) shall disclose to any person or entity this Agreement or the
       other Transaction Documents or the contents thereof or the parties
       thereto, except that such parties may make such disclosure (x) to their
       directors, officers, employees and advisors, and potential bank creditors
       and investors, so long as they shall have advised such persons of the
       obligation of confidentiality herein and for whose breach or default the
       disclosing party shall be responsible or (y) as required by applicable
       law, rule, regu-


<PAGE>

                                      -12-

       lation or judicial or administrative process (it being expressly
       understood by the parties hereto that the Company will file this
       Agreement with the first report on Form 10-Q filed after the Effective
       Date), provided, that the disclosing party uses commercially reasonable
       efforts to obtain an order or ruling protecting the confidentiality of
       confidential information identified as such by the other party contained
       herein or therein and notifies the other party five business days prior
       to such disclosure so that such other party may, if it chooses, request
       that the Company seek such relief (any such relief, "Confidential
       Treatment"). The parties shall be entitled to seek injunctive or other
       equitable relief in respect of any breach or threatened breach of the
       foregoing covenant without the requirement of posting a bond or other
       collateral.

                     (b) Attached hereto as Annex VII is a press release to be
       issued by the Company in respect of this Agreement and the transactions
       contemplated hereby (the "Initial Press Release"). After the Effective
       Date, the Company will not issue any press release containing, or
       otherwise publicly disclose, any confidential information that is the
       subject of a request for Confidential Treatment (whether or not such
       request has been approved), without obtaining the consent of Elan to the
       contents thereof, which consent shall not be unreasonably withheld or
       delayed; it being understood that if Elan shall not have responded to
       such consent request within three business days, such consent shall be
       deemed given.

              13. Successors and Assigns. This Agreement shall be binding upon
each of the parties hereto and their respective successors and assigns. The
successors and assigns of such persons shall include, without limitation, their
respective receivers, trustees or debtors-in-possession and the successors and
assigns of Elan shall include any transferee of any shares of Series A Preferred
Stock.

              14. Further Assurances. Each of the parties hereto agrees to
execute and deliver or cause to be executed and delivered, all such documents,
instruments and agreements and to take or cause to be taken such further or
other action as may reasonably be deemed necessary or desirable in order to
carry out the intent and purposes of this Agreement.

              15. Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF NEW YORK WITHOUT
GIVING EFFECT TO THE CONFLICT OF LAW PROVISIONS THEREOF.

              16. Severability. Wherever possible, each provision of this
Agreement shall be interpreted in such manner as to be effective and valid under
applicable law, but if any provision of this Agreement shall be prohibited by or
invalid under such law, such provi-


<PAGE>

                                      -13-

sion shall be ineffective to the extent of such prohibition or invalidity
without invalidating the remainder of such provision or the remaining provisions
of this Agreement.

              17. Integration, Etc. This Agreement (together with the Annexes
hereto) is intended to be and constitutes the final, complete and exclusive
Agreement between the parties regarding the subject matter of this Agreement and
all prior or contemporaneous agreements, understandings, representations and
statements, oral or written, are merged into and superseded by this Agreement.
No parol or extrinsic evidence of any kind and no course of dealing or usage of
trade or course of performance shall be used to vary, contradict, supplement or
add to the terms of this Agreement. No amendment or waiver hereof shall be
effective unless in writing and signed by the parties hereto and then only in
the specific instance and for the specific purpose for which given; provided,
except as amended hereby, the Existing Transaction Documents remain unmodified
and in full force and effect.

              IN WITNESS WHEREOF, the parties hereto have caused this Agreement
to be executed and delivered by their respective representatives hereunto duly
authorized as of the date first above written.


BIOJECT MEDICAL TECHNOLOGIES, INC.      ELAN INTERNATIONAL SERVICES, LTD.


By:                                     By:
   -----------------------------------     -------------------------------------

ELAN PHARMACEUTICAL
INVESTMENTS, LTD.


By:
   -----------------------------------