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                                                                     Exhibit 1.1


                                   DYAX CORP.

                            - Shares of Common Stock

                             Underwriting Agreement

                                                                         -, 2000

J.P. Morgan Securities Inc.
Lehman Brothers
Pacific Growth Equities, Inc.
As Representatives of the several underwriters
listed in Schedule I hereto
c/o J.P. Morgan Securities Inc.
60 Wall Street
New York, New York  10260

Ladies and Gentlemen:

         Dyax Corp., a Delaware corporation (the "Company"), proposes to issue
and sell to the several Underwriters listed in Schedule I hereto (the
"Underwriters"), for whom you are acting as representatives (the
"Representatives") an aggregate of ? shares of Common Stock, par value $.01 per
share, of the Company (the "Underwritten Shares") and, for the sole purpose of
covering over-allotments in connection with the sale of the Underwritten Shares,
at the option of the Underwriters, up to an additional ? shares of Common Stock
of the Company (the "Option Shares"). The Underwritten Shares and the Option
Shares are herein referred to as the "Shares". The shares of Common Stock of the
Company to be outstanding after giving effect to the sale of the Shares are
herein referred to as the "Stock".

         As part of the offering contemplated by this Agreement, the
Underwriters have agreed to reserve out of the Underwritten Shares purchased by
them under this Agreement, up to ? percent or ? shares, for sale to the
Company's directors, officers, employees and other parties associated with the
Company (collectively, "Participants"), as set forth in the Prospectus (as
defined herein) under the heading "Underwriting" (the "Directed Share Program").
The Underwritten Shares to be sold by the Underwriters pursuant to the Directed
Share Program (the "Directed Shares") will be sold by the Underwriters pursuant
to this agreement at the public offering price. Any Directed Shares not orally
confirmed for purchase by a Participant by the end of the business day on which
this Agreement is executed will be offered to the public by the Underwriters as
set forth in the Prospectus.

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         The Company has prepared and filed with the Securities and Exchange
Commission (the "Commission") in accordance with the provisions of the
Securities Act of 1933, as amended, and the rules and regulations of the
Commission thereunder (collectively, the "Securities Act"), a registration
statement, including a prospectus, relating to the Shares. The registration
statement as amended, at the time when it shall become effective, including
information (if any) deemed to be part of the registration statement at the time
of effectiveness pursuant to Rule 430A under the Securities Act, is referred to
in this Agreement as the "Registration Statement", and the prospectus in the
form first used to confirm sales of Shares is referred to in this Agreement as
the "Prospectus". If the Company has filed an abbreviated registration statement
pursuant to Rule 462(b) under the Securities Act (the "Rule 462 Registration
Statement"), then any reference herein to the term "Registration Statement"
shall be deemed to include such Rule 462 Registration Statement.

         The Company hereby agrees with the Underwriters as follows:

         1. The Company agrees to issue and sell the Underwritten Shares to the
several Underwriters as hereinafter provided, and each Underwriter, upon the
basis of the representations and warranties herein contained, but subject to the
conditions hereinafter stated, agrees to purchase, severally and not jointly,
from the Company the respective number of Underwritten Shares set forth opposite
such Underwriter's name in Schedule I hereto at a purchase price per share of $?
(the "Purchase Price").

         In addition, the Company agrees to issue and sell the Option Shares to
the several Underwriters as hereinafter provided, and the Underwriters, on the
basis of the representations and warranties herein contained, but subject to the
conditions hereinafter stated, shall have the option to purchase, severally and
not jointly, from the Company up to an aggregate of ? Option Shares at the
Purchase Price, for the sole purpose of covering over-allotments (if any) in the
sale of Underwritten Shares by the several Underwriters.

         If any Option Shares are to be purchased, the number of Option Shares
to be purchased by each Underwriter shall be the number of Option Shares which
bears the same ratio to the aggregate number of Option Shares being purchased as
the number of Underwritten Shares set forth opposite the name of such
Underwriter in Schedule I hereto (or such number increased as set forth in
Section 9 hereof) bears to the aggregate number of Underwritten Shares being
purchased from the Company by the several Underwriters, subject, however, to
such adjustments to eliminate any fractional Shares as the Representatives in
their sole discretion shall make.

         The Underwriters may exercise the option to purchase the Option Shares
at any time on or before the thirtieth day following the date of this Agreement,
by delivery of written notice from the Representatives to the Company. Such
notice shall set forth the aggregate number of Option Shares as to which the
option is being exercised and the date



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and time when the Option Shares are to be delivered and paid for which may be
the same date and time as the Closing Date (as hereinafter defined) but shall
not be earlier than the Closing Date nor later than the tenth full Business Day
(as hereinafter defined) after the date of such notice (unless such time and
date are postponed in accordance with the provisions of Section 9 hereof). Any
such notice shall be given at least two Business Days prior to the date and time
of delivery specified therein.

         2. The Company understands that the Underwriters intend (i) to make a
public offering of the Shares as soon after (A) the Registration Statement has
become effective and (B) the parties hereto have executed and delivered this
Agreement, as in the judgment of the Representatives is advisable and (ii)
initially to offer the Shares upon the terms set forth in the Prospectus.

         3. Payment for the Shares shall be made by wire transfer in immediately
available federal funds to the account specified by the Company to the
Representatives in the case of the Underwritten Shares, on ?, 2000 or at such
other time on the same or such other date, not later than the fifth Business Day
thereafter, as the Representatives and the Company may agree upon in writing or,
in the case of the Option Shares, on the date and time specified by the
Representatives in the written notice of the Underwriters' election to purchase
such Option Shares. The time and date of such payment for the Underwritten
Shares is referred to herein as the "Closing Date" and the time and date for
such payment for the Option Shares, if other than the Closing Date, are herein
referred to as the "Additional Closing Date". As used herein, the term "Business
Day" means any day other than a day on which banks are permitted or required to
be closed in New York City.

         Payment for the Shares to be purchased on the Closing Date or the
Additional Closing Date, as the case may be, shall be made against delivery to
the Representatives for the respective accounts of the several Underwriters of
the Shares to be purchased on such date registered in such names and in such
denominations as the Representatives shall request in writing not later than two
full Business Days prior to the Closing Date or the Additional Closing Date, as
the case may be, with any transfer taxes payable in connection with the transfer
to the Underwriters of the Shares duly paid by the Company. The certificates for
the Shares will be made available for inspection and packaging by the
Representatives at the office of J.P. Morgan Securities Inc. set forth above not
later than 1:00 p.m., New York City time, on the Business Day prior to the
Closing Date or the Additional Closing Date, as the case may be.

         4. The Company represents and warrants to each Underwriter that:

                  (a) no order preventing or suspending the use of any
preliminary prospectus has been issued by the Commission, and each preliminary
prospectus filed as part of the Registration Statement as originally filed or as
part of any amendment thereto, or filed pursuant to Rule 424 under the
Securities Act, complied when so filed in all



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material respects with the Securities Act, and did not contain an untrue
statement of a material fact or omit to state a material fact required to be
stated therein or necessary to make the statements therein, in the light of the
circumstances under which they were made, not misleading; PROVIDED that this
representation and warranty shall not apply to any statements or omissions made
in reliance upon and in conformity with information relating to any Underwriter
furnished to the Company in writing by such Underwriter through the
Representatives expressly for use therein;

                  (b) no stop order suspending the effectiveness of the
Registration Statement has been issued and no proceeding for that purpose has
been instituted or, to the knowledge of the Company, threatened by the
Commission; and the Registration Statement and Prospectus (as amended or
supplemented if the Company shall have furnished any amendments or supplements
thereto) comply, or will comply, as the case may be, in all material respects
with the Securities Act and do not and will not, as of the applicable effective
date as to the Registration Statement and any amendment thereto and as of the
date of the Prospectus and any amendment or supplement thereto, 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 not misleading,
and the Prospectus, as amended or supplemented, if applicable, at the Closing
Date or Additional Closing Date, as the case may be, will not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements therein, in light of the circumstances under which they were
made, not misleading; except that the foregoing representations and warranties
shall not apply to statements or omissions in the Registration Statement or the
Prospectus made in reliance upon and in conformity with information relating to
any Underwriter furnished to the Company in writing by such Underwriter through
the Representatives expressly for use therein;

                  (c) the financial statements, and the related notes thereto,
included in the Registration Statement and the Prospectus present fairly the
consolidated financial position of the Company and its consolidated subsidiaries
as of the dates indicated and the results of their operations and changes in
their consolidated cash flows for the periods specified; said financial
statements have been prepared in conformity with generally accepted accounting
principles applied on a consistent basis, and the supporting schedules included
in the Registration Statement present fairly the information required to be
stated therein. The selected consolidated financial data included in the
Prospectus present fairly the information shown therein and have been compiled
on a basis consistent with that of the audited consolidated financial statements
included in the Registration Statement; the pro forma as adjusted financial
information included in the Registration Statement and the Prospectus presents
fairly the information shown therein, and has been properly compiled on the
bases described therein, and the assumptions used in the preparation thereof are
reasonable and the adjustments used therein are appropriate to give effect to
the transactions and circumstances referred to therein.



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                  (d) since the respective dates as of which information is
given in the Registration Statement and the Prospectus, there has not been any
change in the capital stock or long-term debt of the Company or any of its
subsidiaries, or any material adverse change, or any development involving a
prospective material adverse change, in or affecting the general affairs,
business, prospects, management, financial position, stockholders' equity or
results of operations of the Company and its subsidiaries, taken as a whole (a
"Material Adverse Effect"), otherwise than as set forth or contemplated in the
Prospectus; and except as set forth or contemplated in the Prospectus neither
the Company nor any of its subsidiaries has entered into any transaction or
agreement (whether or not in the ordinary course of business) material to the
Company and its subsidiaries taken as a whole;

                  (e) the Company has been duly incorporated and is validly
existing as a corporation in good standing under the laws of the State of
Delaware, with power and authority (corporate and other) to own its properties
and conduct its business as described in the Prospectus, and has been duly
qualified as a foreign corporation for the transaction of business and is in
good standing under the laws of each other jurisdiction in which it owns or
leases properties, or conducts any business, so as to require such
qualification, other than where the failure to be so qualified or in good
standing would not reasonably be expected to have a Material Adverse Effect;

                  (f) each of the Company's subsidiaries has been duly
incorporated and is validly existing as a corporation under the laws of its
jurisdiction of incorporation, with power and authority (corporate and other) to
own its properties and conduct its business as described in the Prospectus, and
has been duly qualified as a foreign corporation for the transaction of business
and is in good standing under the laws of each jurisdiction in which it owns or
leases properties, or conducts any business, so as to require such
qualification, other than where the failure to be so qualified or in good
standing could not reasonably be expected to have a Material Adverse Effect; and
all the outstanding shares of capital stock of each subsidiary of the Company
have been duly authorized and validly issued, are fully-paid and non-assessable,
and (except, in the case of foreign subsidiaries, for directors' qualifying
shares) are owned by the Company, directly or indirectly, free and clear of all
liens, encumbrances, security interests and claims and except as disclosed in
the Prospectus, there are no encumbrances or restrictions on the ability of any
subsidiary to pay any dividends or make any distributions on such subsidiary's
capital stock, to make any loans or advances to, or investments in, the Company
or any other subsidiary or to transfer any of its property or assets to the
Company or any other subsidiary;

                  (g) this Agreement has been duly authorized, executed and
delivered by the Company;



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                  (h) the Company has an authorized capitalization as set forth
under the caption "Capitalization" in the Prospectus and such authorized capital
stock conforms as to legal matters to the description thereof set forth in the
Prospectus, and all of the outstanding shares of capital stock of the Company
have been duly authorized and validly issued, are fully-paid and non-assessable
and are not subject to any preemptive or similar rights that have not been
waived in writing; PROVIDED that a copy of any and all such written waivers have
been delivered to counsel for the underwriters prior to the date hereof; and,
except as described in or expressly contemplated by the Prospectus, there are no
outstanding rights (including, without limitation, pre-emptive rights), warrants
or options to acquire, or instruments convertible into or exchangeable for, or
any contracts or commitments to issue or sell, any shares of capital stock or
other equity interest in the Company or any of its subsidiaries, or any
contract, commitment, agreement, understanding or arrangement of any kind
relating to the issuance of any capital stock of the Company or any such
subsidiary, any such convertible or exchangeable securities or any such rights,
warrants or options. The description of the Company's stock option and purchase
plans and the options or other rights granted and exercised thereunder set forth
in the Prospectus accurately and fairly describe, in all material respects, the
information required to be shown with respect to such plans, arrangements,
options and rights;

                  (i) the Shares to be issued and sold by the Company hereunder
have been duly authorized, and, when issued and delivered to and paid for by the
Underwriters in accordance with the terms of this Agreement, will be duly issued
and will be fully paid and non-assessable and will conform to the descriptions
thereof in the Prospectus; and the issuance of the Shares is not subject to any
preemptive or similar rights that have not been waived in writing; PROVIDED that
a copy of any and all such written waivers have been delivered to counsel for
the underwriters prior to the date hereof;

                  (j) Intentionally omitted

                  (k) neither the Company nor any of its subsidiaries is, or
with the giving of notice or lapse of time or both would be, in violation of or
in default under, its certificate of incorporation, by-laws or other constituent
document or any indenture, mortgage, deed of trust, loan agreement or other
agreement or instrument to which the Company or any of its subsidiaries is a
party or by which it or any of them or any of their respective properties is
bound, except for violations and defaults which individually and in the
aggregate are not material to the Company and its subsidiaries taken as a whole;
the issue and sale of the Shares and the performance by the Company of its
obligations under this Agreement and the consummation of the transactions
contemplated herein will not conflict with or result in a breach of any of the
terms or provisions of, or constitute a default under, any indenture, mortgage,
deed of trust, loan agreement or other agreement or instrument to which the
Company or any of its subsidiaries is a party or by which the Company or any of
its subsidiaries is bound or to which any of the property or assets of the
Company or any of its subsidiaries is subject, nor will any such action result
in any



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violation of the provisions of the Certificate of Incorporation or the By-Laws
of the Company or any applicable law or statute or any order, rule or regulation
of any court or governmental agency or body having jurisdiction over the
Company, its subsidiaries or any of their respective properties; and no consent,
approval, authorization, order, license, registration or qualification of or
with any such court or governmental agency or body is required for the issue and
sale of the Shares or the consummation by the Company of the transactions
contemplated by this Agreement, except such consents, approvals, authorizations,
orders, licenses, registrations or qualifications as have been obtained under
the Securities Act and as may be required under state securities or Blue Sky
Laws in connection with the purchase and distribution of the Shares by the
Underwriters;

                  (l) other than as set forth or contemplated in the Prospectus,
there are no legal or governmental investigations, actions, suits or proceedings
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 or to
which the Company or any of its subsidiaries is or may be a party or to which
any property of the Company or any of its subsidiaries is or may be the subject
which, if determined adversely to the Company or any of its subsidiaries, could
reasonably be expected to individually or in the aggregate, result in a Material
Adverse Effect, and to the Company's knowledge, no such proceedings are
threatened or contemplated by governmental authorities or threatened by others;
and there are no statutes, regulations, contracts or other documents that are
required to be described in the Registration Statement or Prospectus or to be
filed as exhibits to the Registration Statement that are not described or filed
as required and all such descriptions are accurate and complete in all material
respects;

                  (m) except as disclosed in or specifically contemplated by the
Prospectus, to the knowledge of the Company, the Company and its subsidiaries
own, possess or have legally enforceable rights to use on reasonable terms, or
can acquire on reasonable terms, adequate patents, patent rights, licenses,
inventions, copyrights, know-how (including trade secrets and other unpatented
and/or unpatentable proprietary or confidential information, systems or
procedures), trademarks, service marks, trade names or other intellectual
property, including without limitation, all of the intellectual property
described in the Registration Statement and the Prospectus as being owned or
licensed by the Company and its subsidiaries (collectively, "Intellectual
Property") necessary to carry on the business now operated by them. Except as
otherwise specifically described in the Prospectus, neither the Company nor any
of its subsidiaries has received any notice or is otherwise aware of any
infringement of or conflict with asserted rights of others with respect to any
Intellectual Property or of any facts or circumstances which could reasonably be
expected to render any Intellectual Property invalid or inadequate to protect
the interest of the Company or any of its subsidiaries therein, which
infringement or conflict (if the subject of any unfavorable decision, ruling or
finding) or invalidity or inadequacy, singly or in the aggregate, could not
result in a material adverse effect;



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                  (n) the Company has provided to counsel for the
Representatives a complete and correct list, dated ?, 2000, of all patents owned
(the "Owned Patents") or licensed (the "Licensed Patents") by the Company and
its subsidiaries and all patent applications (the "Patent Applications") filed
by or on behalf of the Company and its subsidiaries, including without
limitation, all of the Owned Patents, Licensed Patents and Patent Applications
described in the Registration Statement and the Prospectus as being owned or,
licensed or applied for by the Company and its subsidiaries ( the "Scheduled
Patents"); all of the Owned Patents and Patent Applications have been duly
registered with, filed in or issued by, as the case may be, the United States
Patent and Trademark Office or other filing offices, domestic or foreign, to the
extent necessary or desirable to ensure full protection under any applicable law
or regulation, and such registrations, filings, issuances and other actions
remain in full force and effect; except as specifically described in the
Prospectus, there are no outstanding licenses or other agreements that relate to
or restrict the use by the Company and its subsidiaries of the Owned Patents; no
other entity or individual has any right or claim in any Owned Patent, Patent
Application or any Patent to be issued therefrom, except as specifically
described in the Prospectus with respect to European Patent No. 436,597, no
Owned Patent has been or is now involved in any interference, reissue,
reexamination or opposition proceeding in the United States Patent and Trademark
Office or other filing office domestic or foreign; to the knowledge of the
Company, there is no patent or patent application, or any prior art, of any
person that conflicts in any material respect with any Schedule Patent, Owned
Patent or Patent Application or invalidates any claim that the Company or any of
its Subsidiaries has in any Scheduled Patent, and each Owned Patent or Patent
Application; the Company has no knowledge of unpaid past due maintenance fees
relating to the Scheduled Patents, and no Owned Patent has lapsed nor has any
Patent Application been abandoned;

                  (o) the Company has provided to counsel for the
Representatives a complete and correct list, dated ?, 2000, of all trademarks
and service marks (the "Registered Marks") owned by the Company and its
subsidiaries and all trademark and service mark applications (the "Applied
Marks") filed by or on behalf of the Company and its subsidiaries. All of the
Registered Marks and Applied Marks have been duly registered with, filed in or
issued by, as the case may be, the United Stated Patent and Trademark Office or
other filing offices, domestic or foreign, to the extent necessary or desirable
to ensure full protection under any applicable law or regulation, and such
registrations, filings, issuances and other actions remain in full force and
effect; the Company or a subsidiary of the Company is the sole and exclusive
owner of all right, title and interest in the Registered Marks. Neither the
Company nor any of its subsidiaries has allowed any Applied Marks or Registered
Marks to be abandoned, to be canceled or to lapse, as the case may be; there are
no claims, actions or proceedings pending or, to the knowledge of the Company,
threatened challenging the validity of any of the Registered Marks or the
registration relating to any Applied Marks;



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                  (p) to the Company's knowledge, each current and former
employee, each consultant, each licensee, each collaborator and each customer
who has access to proprietary information of the Company and its subsidiaries
has executed a confidentiality agreement and all such agreements are presently
in effect and are enforceable;

                  (q) each of the Company and its subsidiaries has obtained and
possesses, and at the Closing Date will possess, such permits, licenses,
approvals, consents and other authorizations (including, licenses, pharmacy
licenses, accreditation and other similar documentation or approvals from any
foreign, federal, state or local health departments) (collectively,
"Governmental Permits") from, and has made all declarations and filings with,
the appropriate foreign, federal, state or local regulatory agencies or bodies,
including, without limitation, the United States Food and Drug Administration
("FDA"), necessary to conduct the business now operated by them; the Company and
its subsidiaries are in compliance with the terms and conditions of all such
Governmental Permits and all applicable FDA rules and regulations, guidelines
and policies, except where the failure so to comply could not reasonably be
expected to, singly or in the aggregate, result in a Material Adverse Effect;
all of the Governmental Licenses are valid and in full force and effect, except
where the invalidity of such Governmental Licenses could not reasonably be
expected to result in a Material Adverse Effect; and neither the Company nor any
of its subsidiaries has received any notice of proceedings relating to the
revocation or modification of any such Governmental Permits which, singly or in
the aggregate, if the subject of any unfavorable decision, ruling or finding,
could reasonably be expected to result in a material adverse effect; and each of
the Company and its subsidiaries is in compliance with all foreign, federal,
state and local laws, and regulations, including, without limitation, all
applicable FDA rules and regulations, guidelines and policies, relating to the
conduct of its business as conducted as of the date hereof, except where the
failure to be in compliance could not reasonably be expected to result in a
Material Adverse Effect;

                  (r) the pre-clinical and clinical trials conducted by or on
behalf of the Company or in which the Company has participated, that are
described in the Prospectus, or the results of which are referred to in the
Prospectus, are the only pre-clinical or clinical trials currently being
conducted by or on behalf of the Company and, to the Company's knowledge, such
trials were and, if still pending, are being, conducted in accordance with
experimental protocols, procedures and controls pursuant to accepted
professional scientific standards; the descriptions, if any, of the results of
such trials contained in the Prospectus are accurate and complete in all
material respects. The Company has no knowledge of any other trials, the results
of which call into question the results of the pre-clinical or clinical trials
described in the Prospectus. The Company has not received any notices or
correspondence from the FDA or any other foreign, federal, state or local
governmental agency, requiring the termination, suspension or modification of
any pre-clinical and clinical trials conducted by, or on behalf of, the Company
or in



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which the Company has participated or the results of which are referred to in
the Prospectus;

                  (s) the Company and its subsidiaries do not own any real
property and have good and marketable title to all personal property owned by
them which is necessary to operate their businesses as presently conducted, in
each case free and clear of all liens, encumbrances and defects except such as
are described or referred to in the Prospectus or such as do not materially and
adversely affect the value of such property and do not interfere with the use
made or proposed to be made of such property by the Company and its
subsidiaries; and any real property and buildings held under lease by the
Company and its subsidiaries are held by them under valid, existing and
enforceable leases with such exceptions as are not material and do not interfere
with the use made or proposed to be made of such property and buildings by the
Company or its subsidiaries;

                  (t) no relationship, direct or indirect, exists between or
among the Company or any or its subsidiaries on the one hand, and the directors,
officers, stockholders, customers or suppliers of the Company or any of its
subsidiaries on the other hand, which is required by the Securities Act to be
described in the Registration Statement and the Prospectus which is not so
described;

                  (u) except as specifically set forth in or specifically
contemplated by the Prospectus, no person has the right to require the Company
to register any securities for offering and sale under the Securities Act by
reason of the filing of the Registration Statement with the Commission or the
issue and sale of the Shares or otherwise;

                  (v) the Company is not and, after giving effect to the
offering and sale of the Shares, will not be an "investment company" or an
entity "controlled" by an "investment company", as such terms are defined in the
Investment Company Act of 1940, as amended (the "Investment Company Act");

                  (w) PricewaterhouseCoopers, LLP, who have certified certain
financial statements of the Company and its subsidiaries, are independent public
accountants as required by the Securities Act;

                  (x) the Company and its subsidiaries have filed all federal,
state, local and foreign tax returns which have been required to be filed and
have paid all taxes shown thereon and all assessments received by them or any of
them to the extent that such taxes have become due and are not being contested
in good faith; and, except as disclosed in the Registration Statement and the
Prospectus, there is no tax deficiency which has been or might reasonably be
expected to be asserted or threatened against the Company or any subsidiary;



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                  (y) the Company has not taken nor will it take, directly or
indirectly, any action designed to, or that could, cause or result in
stabilization or manipulation of the price of the Common Stock;

                  (z) there are no existing or, to the best knowledge of the
Company, threatened labor disputes with the employees of the Company or any of
its subsidiaries which could reasonably be expected to have a Material Adverse
Effect;

                  (aa) the Company and its subsidiaries (i) are in and have at
all times been in material compliance with any and all applicable foreign,
federal, state and local laws and regulations ("Environmental Laws") relating to
the protection of human health and safety, the environment or any substance,
chemical, compound, product, pollutant, contaminant or material that is
classified or regulated as a "hazardous substance," "hazardous material,"
"hazardous waste," "toxic substance" or words of similar import under any
environmental law, including, without limitation, asbestos, polychlorinated
biphenyls, urea-formaldehyde insulation, petroleum and petroleum products
(collectively, "Hazardous Substances"), (ii) have received all permits,
licenses, authorizations or other approvals required of them under applicable
Environmental Laws to conduct their respective businesses, (iii) are and have at
all times been in material compliance with all terms and conditions of any such
permit, license, authorization or other approval, and (iv) to the knowledge of
the Company, no material violation by the Company or any of its subsidiaries is
being alleged or threatened or has at any time been alleged or threatened of any
applicable Environmental Law relating to any of their respective properties and
assets (including the real property and the properties currently or formerly
owned or leased) or the use or ownership thereof, or to their respective
businesses and operations;

                  (bb) to the knowledge of the Company, there are no complaints,
notices, directives, orders, claims, litigation, investigations, judicial or
administrative proceedings, judgments, letters or other communication from any
governmental agency, office or other authority, or any third party, involving
violations of Environmental Laws or releases of Hazardous Substances from (i)
any assets, properties or businesses of the Company, its subsidiaries or any
predecessor in interest; (ii) from adjoining properties or businesses; or (iii)
from or onto any facilities which received Hazardous Substances generated by the
Company, its subsidiaries or any predecessor in interest ("Environmental
Claims") pending, or to the knowledge of the Company or any of its subsidiaries,
threatened, against the Company or any of its subsidiaries, and to the knowledge
of the Company or any of its subsidiaries, there are no circumstances that can
reasonably form the basis of any such Environmental Claim, including with
respect to any off-site disposal location used by the Company or any of its
subsidiaries, or with respect to any previously owned or operated facility;



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                  (cc) neither the Company nor any of its subsidiaries has
conducted any remedial action or performed any studies, investigations or care,
including all actions required (i) to clean up, remove, treat or in any other
way remediate any Hazardous Substance or (ii) to prevent the release of
Hazardous Substances so that they do not migrate or endanger or threaten to
endanger public health or welfare or the environment, related to any such
Hazardous Substances, relating to any release or threatened release of Hazardous
Substances at any real property currently or formerly owned, leased or used or
at any other off-site location in respect of the business, either voluntarily or
pursuant to the requirements of any Environmental Law;

                  (dd) the Company has provided to the Underwriters all
information, including, without limitation, all environmental site assessments,
compliance audits, studies, allegations of noncompliance or liability in its or
its representatives' possession, custody or control relating to the
environmental conditions on, under or about the properties or assets currently
or formerly owned, leased, operated or used by the Company or any of its
subsidiaries or any predecessor in interest thereto or relating to the release
of Hazardous Substances by the Company or its subsidiaries or any predecessors
in interest;

                  (ee) each employee benefit plan, within the meaning of Section
3(3) of the Employee Retirement Income Security Act of 1974, as amended,
("ERISA") that is maintained, administered or contributed to by the Company or
any of its affiliates for employees or former employees of the Company and its
affiliates has been maintained in compliance with its terms and the requirements
of any applicable statutes, orders, rules and regulations, including but not
limited to ERISA and the Internal Revenue Code of 1986, as amended, ("Code"). No
prohibited transaction, within the meaning of Section 406 of ERISA or Section
4975 of the Code has occurred with respect to any such plan excluding
transactions effected pursuant to a statutory or administrative exemption. For
each such plan which is subject to the funding rules of Section 412 of the Code
or Section 302 of ERISA no "accumulated funding deficiency" as defined in
Section 412 of the Code has been incurred, whether or not waived, and the fair
market value of the assets of each such plan (excluding for these purposes
accrued but unpaid contributions) exceeded the present value of all benefits
accrued under such plan determined using reasonable actuarial assumptions;

                  (ff) the Company and each to its subsidiaries are insured by
insurers of recognized financial responsibility against such losses and risks of
the type and in such amounts as are prudent and customary for companies of
similar sizes and stages of development as the Company in the industries in
which they operate; neither the Company nor any of its subsidiaries has been
refused any insurance coverage sought or applied for within the past two years;
and the Company does not have any reason to believe that it or any of its
subsidiaries will not be able to renew its existing insurance coverage as and
when such coverage expires or to obtain similar coverage from similar



                                       12
<PAGE>

insurers as may be necessary to continue its operations except where the failure
to renew or maintain such coverage could not reasonably be expected to result in
a Material Adverse Effect. The officers and directors of the Company are insured
by insurers of recognized financial responsibility against such losses and risks
and in such amounts as the Company believes are prudent and customary for
officers' and directors' liability insurance of a public company and as the
Company believes could cover claims which could reasonably be expected to be
made in connection with the issuance of the Shares; and the Company has no
reason to believe that it will not be able to renew its existing directors' and
officers' liability insurance coverage as and when such coverage expires or to
obtain similar coverage from similar insurers as may be necessary to cover its
officers and directors;

                  (gg) except as disclosed in the Prospectus, there are no
outstanding loans, advances, or guarantees of indebtedness by the Company or any
of its subsidiaries to or for the benefit of, or any transactions, agreements or
other relationships with, any of the executive officers or directors of the
Company or any of the members of the families of any of them that would be
required to be so disclosed under the Securities Act on Form S-1;

                  (hh) the statistical and market-related data included in the
Prospectus were accurately derived from sources which the Company reasonably and
in good faith believes to be accurate, reasonable and reliable;

                  (ii) the Company has established and will maintain a system of
internal accounting controls sufficient to provide reasonable assurances that
transactions were and are executed in accordance with management's general or
specific authorization; transactions were and are recorded as necessary to
permit preparation of financial statements in conformity with generally accepted
accounting principles and to maintain accountability for assets; access to
assets was and is permitted only in accordance with a management's general or
specific authorizations; and the recorded accountability for assets was and is
compared with existing assets at reasonable intervals and appropriate action was
and is taken with respect to any differences; and

                  (jj) the registration statement, the Prospectus and any
preliminary prospectus comply, and any further amendments or supplements thereto
will comply, with any applicable laws or regulations of foreign jurisdictions in
which the Prospectus or any preliminary prospectus, as amended or supplemented,
if applicable, are distributed in connection with the Directed Share Program;
and no authorization, approval, consent, license, order, registration or
qualification of or with any government, governmental instrumentality or court,
other than such as have been obtained, is necessary under the securities laws
and regulations of foreign jurisdictions in which the Directed Shares are
offered outside the United States.



                                       13
<PAGE>

         5. The Company covenants and agrees with each of the several
Underwriters as follows:

                  (a) to use its best efforts to cause the Registration
Statement to become effective at the earliest possible time and, if required, to
file the final Prospectus with the Commission within the time periods specified
by Rule 424(b) and Rule 430A under the Securities Act and to furnish copies of
the Prospectus to the Underwriters in New York City prior to 10:00 a.m., New
York City time, on the Business Day next succeeding the date of this Agreement
in such quantities as the Representatives may reasonably request;

                  (b) to deliver, at the expense of the Company, to the
Representatives signed copies of the Registration Statement (as originally
filed) and each amendment thereto, in each case including exhibits, and to each
other Underwriter a conformed copy of the Registration Statement (as originally
filed) and each amendment thereto, in each case without exhibits and, during the
period set forth in paragraph (e) below, to each of the Underwriters as many
copies of the Prospectus (including all amendments and supplements thereto) as
the Representatives may reasonably request;

                  (c) before filing any amendment or supplement to the
Registration Statement or the Prospectus, whether before or after the time the
Registration Statement becomes effective, to furnish to the Representatives a
copy of the proposed amendment or supplement for review and not to file any such
proposed amendment or supplement to which the Representatives reasonably object;

                  (d) to advise the Representatives promptly, and to confirm
such advice in writing (i) when the Registration Statement has become effective,
(ii) when any amendment to the Registration Statement has been filed or becomes
effective, (iii) when any supplement to the Prospectus or any amended Prospectus
has been filed and to furnish the Representatives with copies thereof, (iv) of
any request by the Commission for any amendment to the Registration Statement or
any amendment or supplement to the Prospectus or for any additional information,
(v) of the issuance by the Commission of any stop order suspending the
effectiveness of the Registration Statement or of any order preventing or
suspending the use of any preliminary prospectus or the Prospectus or the
initiation or threatening of any proceeding for that purpose, (vi) of the
occurrence of any event, within the period set forth in paragraph (e) below, as
a result of which the Prospectus as then amended or supplemented would include
an untrue statement of a material fact or omit to state any material fact
necessary in order to make the statements therein, in the light of the
circumstances when the Prospectus is delivered to a purchaser, not misleading,
and (vii) of the receipt by the Company of any notification with respect to any
suspension of the qualification of the Shares for offer and sale in any
jurisdiction or the initiation or threatening of any proceeding for such
purpose; and to use its best efforts to prevent the issuance of any such stop
order, or of any order preventing or suspending



                                       14
<PAGE>

the use of any preliminary prospectus or the Prospectus, or of any order
suspending any such qualification of the shares, or notification of any such
order thereof and, if issued, to obtain as soon as possible the withdrawal
thereof;

                  (e) if, during such period of time after the first date of the
public offering of the Shares as in the reasonable opinion of counsel for the
Underwriters a prospectus relating to the Shares is required by law to be
delivered in connection with sales by the Underwriters or any dealer, any event
shall occur as a result of which it is necessary to amend or supplement the
Prospectus in order to make the statements therein, in the light of the
circumstances when the Prospectus is delivered to a purchaser, not misleading,
or if it is necessary to amend or supplement the Prospectus to comply with law,
forthwith to prepare and furnish, at the expense of the Company, to the
Underwriters and to the dealers (whose names and addresses the Representatives
will furnish to the Company) to which Shares may have been sold by the
Representatives on behalf of the Underwriters and to any other dealers upon
request, such amendments or supplements to the Prospectus as may be necessary so
that the statements in the Prospectus as so amended or supplemented will not, in
the light of the circumstances when the Prospectus is delivered to a purchaser,
be misleading or so that the Prospectus will comply with law;

                  (f) to endeavor to qualify the Shares for offer and sale under
the securities or Blue Sky laws of such jurisdictions as the Representatives
shall reasonably request and to continue such qualification in effect so long as
reasonably required for distribution of the Shares; PROVIDED that the Company
shall not be required to file a general consent to service of process in any
jurisdiction;

                  (g) to make generally available to its security holders and to
the Representatives as soon as practicable an earnings statement covering a
period of at least twelve months beginning with the first fiscal quarter of the
Company occurring after the effective date of the Registration Statement, which
shall satisfy the provisions of Section 11(a) of the Securities Act and Rule 158
of the Commission promulgated thereunder;

                  (h) for five years from the date hereof, to furnish to the
Representatives copies of all reports or other communications (financial or
other) furnished to holders of the Shares, and copies of any reports and
financial statements furnished to or filed with the Commission or any national
securities exchange;

                  (i) for a period of 180 days after the date of the initial
public offering of the Shares not to (i) offer, pledge, announce the intention
to sell, sell, contract to sell, sell any option or contract to purchase,
purchase any option or contract to sell, grant any option, right or warrant to
purchase or otherwise transfer or dispose of, directly or indirectly, any shares
of Stock or any securities convertible into or exercisable or exchangeable for
Stock or (ii) enter into any swap or other agreement that transfers, in whole or
in part, any of the economic consequences of ownership of the Stock, whether



                                       15
<PAGE>

any such transaction described in clause (i) or (ii) above is to be settled by
delivery of Stock or such other securities, in cash or otherwise without the
prior written consent of the Representatives, other than the Shares to be sold
hereunder and any shares of Stock of the Company issued upon the exercise of
options granted under existing employee stock option plans;

                  (j) to use the net proceeds received by the Company from the
sale of the Shares pursuant to this Agreement in the manner specified in the
Prospectus under the caption "Use of Proceeds";

                  (k) to use its best efforts to list for quotation the Shares
on the National Association of Securities Dealers Automated Quotations National
Market (the "Nasdaq National Market");

                  (l) in connection with the Directed Share Program, to ensure
that the Directed Shares will be restricted to the extent required by the
National Association of Securities Dealers, Inc. (the "NASD") or the NASD rules
from sale, transfer, assignment, pledge or hypothecation for a period of three
months following the date of the effectiveness of the Registration Statement.
The Designated Underwriters will notify the Company as to which Participants
will need to be so restricted. The Company will direct the transfer agent to
place stop transfer restrictions upon such securities for such period of time;

                  (m) to comply with the requirements of Rule 463 under the
Securities Act; and

                  (n) whether or not the transactions contemplated in this
Agreement are consummated or this Agreement is terminated, to pay or cause to be
paid all costs and expenses incident to the performance of its obligations
hereunder, including without limiting the generality of the foregoing, all costs
and expenses (i) incident to the preparation, issuance, execution and delivery
of the Shares, (ii) incident to the preparation, printing and filing under the
Securities Act of the Registration Statement, the Prospectus and any preliminary
prospectus (including in each case all exhibits, amendments and supplements
thereto), (iii) incurred in connection with the registration or qualification of
the Shares under the laws of such jurisdictions as the Representatives may
designate (including fees of counsel for the Underwriters and its
disbursements), (iv) in connection with the listing of the Shares on the Nasdaq
National Market, (v) related to the filing with, and clearance of the offering
by, the National Association of Securities Dealers, Inc., (vi) in connection
with the printing (including word processing and duplication costs) and delivery
of this Agreement, the Preliminary and Supplemental Blue Sky Memoranda and the
furnishing to the Underwriters and dealers of copies of the Registration
Statement and the Prospectus, including mailing and shipping, as herein
provided, (vii) any expenses incurred by the Company in connection with a "road
show"



                                       16
<PAGE>

presentation to potential investors, (viii) all costs and expenses of the
Underwriters, including the fees and disbursements of Counsel for the
Underwriters, in connection with matters related to the Directed Share Program,
(ix) the cost of preparing stock certificates and (x) the cost and charges of
any transfer agent and any registrar; PROVIDED, HOWEVER, that the Company's
obligation for any expenses described in clause (viii) shall be limited to such
costs and expenses incurred after April 6, 2000.

         6. The several obligations of the Underwriters hereunder to purchase
the Shares on the Closing Date or the Additional Closing Date, as the case may
be, are subject to the performance by the Company of its obligations hereunder
and to the following additional conditions:

                  (a) the Registration Statement shall have become effective (or
if a post-effective amendment is required to be filed under the Securities Act,
such post-effective amendment shall have become effective) not later than 5:00
p.m., New York City time, on the date hereof; and no stop order suspending the
effectiveness of the Registration Statement or any post-effective amendment
shall be in effect, and no proceedings for such purpose shall be pending before
or threatened by the Commission; the Prospectus shall have been filed with the
Commission pursuant to Rule 424(b) within the applicable time period prescribed
for such filing by the rules and regulations under the Securities Act and in
accordance with Section 5(a) hereof; and all requests for additional information
shall have been complied with to the satisfaction of the Representatives;

                  (b) the representations and warranties of the Company
contained herein are true and correct on and as of the Closing Date or the
Additional Closing Date, as the case may be, as if made on and as of the Closing
Date or the Additional Closing Date, as the case may be, and the Company shall
have complied with all agreements and all conditions on its part to be performed
or satisfied hereunder at or prior to the Closing Date or the Additional Closing
Date, as the case may be;

                  (c) subsequent to the execution and delivery of this Agreement
and prior to the Closing Date or the Additional Closing Date, as the case may
be, there shall not have occurred any downgrading, nor shall any notice have
been given of (i) any downgrading, (ii) any intended or potential downgrading or
(iii) any review or possible change that does not indicate an improvement, in
the rating accorded any securities of or guaranteed by the Company by any
"nationally recognized statistical rating organization", as such term is defined
for purposes of Rule 436(g)(2) under the Securities Act;

                  (d) since the respective dates as of which information is
given in the Prospectus there shall not have been any change in the capital
stock or long-term debt of the Company or any of its subsidiaries or any
material adverse change, or any



                                       17
<PAGE>

development involving a prospective material adverse change, in or affecting the
general affairs, business, prospects, management, financial position,
stockholders' equity or results of operations of the Company and its
subsidiaries, taken as a whole, otherwise than as set forth or contemplated in
the Prospectus, the effect of which in the judgment of the Representatives makes
it impracticable or inadvisable to proceed with the public offering or the
delivery of the Shares on the Closing Date or the Additional Closing Date, as
the case may be, on the terms and in the manner contemplated in the Prospectus;
and neither the Company nor any of its subsidiaries has sustained since the date
of the latest audited financial statements included in the Prospectus any
material loss or interference with its business from fire, explosion, flood or
other calamity, whether or not covered by insurance, or from any labor dispute
or court or governmental action, order or decree, otherwise than as set forth or
contemplated in the Prospectus;

                  (e) the Representatives shall have received on and as of the
Closing Date or the Additional Closing Date, as the case may be, a certificate
of an executive officer of the Company, with specific knowledge about the
Company's financial matters, satisfactory to the Representatives to the effect
set forth in subsections (a) through (d) (with respect to the respective
representations, warranties, agreements and conditions of the Company) of this
Section and to the further effect that there has not occurred any material
adverse change, or any development involving a prospective material adverse
change, in or affecting the general affairs, business, prospects, management,
financial position, stockholders' equity or results of operations of the Company
and its subsidiaries taken as a whole from that set forth or contemplated in the
Registration Statement;

                  (f) Palmer & Dodge LLP, counsel for the Company, shall have
furnished to the Representatives their written opinion, dated the Closing Date
or the Additional Closing Date, as the case may be, in form and substance
satisfactory to the Representatives, to the effect that:

                           (i) the Company is validly existing as a corporation
in good standing under the laws of its jurisdiction of incorporation, with power
and authority (corporate and other) to own its properties and conduct its
business as described in the Prospectus;

                           (ii) the Company has been duly qualified as a foreign
corporation for the transaction of business and is in good standing under the
laws of each other jurisdiction listed on Schedule ? in which it owns or leases
properties, or conducts any business, so as to require such qualification, other
than where the failure to be so qualified or in good standing would not have a
Material Adverse Effect;

                           (iii) each of the Company's subsidiaries has been
duly incorporated and is validly existing as a corporation under the laws of its
jurisdiction of incorporation with power and authority (corporate and other) to
own its properties and



                                       18
<PAGE>

conduct its business as described in the Prospectus and has been duly qualified
as a foreign corporation for the transaction of business and is in good standing
under the laws of each other jurisdiction listed on Schedule ?;

                           (iv) other than as set forth or contemplated in the
Prospectus, to the best of such counsel's knowledge, there are no legal or
governmental investigations, actions, suits or proceedings pending or threatened
against or affecting the Company or any of its subsidiaries or any of their
respective properties or to which the Company or any of its subsidiaries is or
may be a party or to which any property of the Company or its subsidiaries is or
may be the subject which, if determined adversely to the Company or any of its
subsidiaries, could individually or in the aggregate have, or reasonably be
expected to have, a Material Adverse Effect; to the best of such counsel's
knowledge, no such proceedings are threatened or contemplated by governmental
authorities or threatened by others; and such counsel does not know of any
statutes, regulations, contracts or other documents that are required to be
described in the Registration Statement or Prospectus or to be filed as exhibits
to the Registration Statement that are not described or filed as required;

                           (v) this Agreement has been duly authorized, executed
and delivered by the Company;

                           (vi) the authorized capital stock of the Company
conforms as to legal matters to the description thereof contained in the
Prospectus;

                           (vii) the shares of capital stock of the Company
outstanding prior to the issuance of the Shares to be sold by the Company have
been duly authorized and are validly issued, fully paid and non-assessable;

                           (viii) the Shares to be issued and sold by the
Company hereunder have been duly authorized, and when delivered to and paid for
by the Underwriters in accordance with the terms of this Agreement, will be
validly issued, fully paid and non-assessable and the issuance of the Shares is
not subject to any preemptive or similar rights;

                           (ix) to the knowledge of such counsel, except as
specifically set forth in the Prospectus, there are no persons with registration
rights or other similar rights to have any securities registered pursuant to the
Registration Statement or otherwise registered by the Company or any of its
subsidiaries under the Securities Act;

                           (x) the statements in the Prospectus under "Risk
Factors -- Our biopharmaceutical or diagnostic product candidates must undergo
vigorous clinical trials and regulatory approvals, which could substantially
delay or prevent their development or marketing," "Risk Factors -- We use and
generate hazardous materials in our business



                                       19
<PAGE>

and any claims relating to the improper handling, storage, release or disposal
of these materials could be time consuming and expensive," "Risk Factors -- We
may have significant product liability exposure," "Risk Factors --Anti-takeover
provisions in our charter documents and provisions of Delaware Law may make an
acquisition more difficult," "Risk Factors -- Our officers and directors may be
able to block proposals for change in control," "Business -- Government
Regulation," "Business - Collaborations and Licenses," except that we express no
opinion with respect to any patent described therein, "Management -- Board of
Directors," "Management -- Employment Agreements," "Management -- Stock Plans,"
"Certain Relationships and Related Transactions," "Description of Capital
Stock," "Shares Eligible for Future Sale," and in the Registration Statement in
Items 14 and 15, insofar as such statements constitute a summary of the terms of
the Stock, legal matters, documents or proceedings referred to therein, fairly
present the information called for with respect to such terms, legal matters,
documents or proceedings;

                           (xi) such counsel is of the opinion that the
Registration Statement and the Prospectus and any amendments and supplements
thereto (other than the financial statements and related schedules therein, as
to which such counsel need express no opinion) comply as to form in all material
respects with the applicable requirements of the Securities Act and believes
that (other than the financial statements and related schedules therein, as to
which such counsel need express no belief) the Registration Statement and the
prospectus included therein at the time the Registration Statement became
effective did not contain any untrue statement of a material fact or omit to
state a material fact required to be stated therein or necessary to make the
statements therein not misleading, and that the Prospectus, as amended or
supplemented, if applicable, at the time the Prospectus was issued or at the
Closing Date, did not and does not contain any untrue statement of a material
fact or omit to state a material fact necessary in order to make the statements
therein, in the light of the circumstances under which they were made, not
misleading;

                           (xii) neither the Company nor any of its subsidiaries
is, or with the giving of notice or lapse of time or both would be, in violation
of or in default under, its Certificate of Incorporation or By-Laws or similar
constituent documents or its due performance or observation of any material
obligation, agreement, covenant or condition contained in any contract,
indenture, mortgage, deed of trust, loan agreement or other agreement or
instrument that is described or referred to in the Registration Statement or the
Prospectuses or filed or incorporated by reference as an exhibit to the
Registration Statement, the issue and sale of the Shares being delivered on the
Closing Date or the Additional Closing Date, as the case may be, and the
performance by the Company of its obligations under this Agreement and the
consummation of the transactions contemplated herein will not conflict with or
result in a breach of any of the terms or provisions of, or constitute a default
in the due performance or observation of any material obligation, agreement,
covenant or condition contained in any contract, indenture, mortgage, deed of



                                       20
<PAGE>


trust, loan agreement or other agreement or instrument that is described or
referred to in the Registration Statement or the Prospectuses or filed or
incorporated by reference as an exhibit to the Registration Statement, nor will
any such action result in any violation of the provisions of the Certificate of
Incorporation or the By-Laws or similar constituent documents of the Company or
any applicable law or statute or any order, rule or regulation of any court or
governmental agency or body having jurisdiction over the Company, its
subsidiaries or any of their respective properties;

                           (xiii) no consent, approval, authorization, order,
license, registration or qualification of or with any court or governmental
agency or body is required for the issue and sale of the Shares or the
consummation of the other transactions contemplated by this Agreement, except
such consents, approvals, authorizations, orders, licenses, registrations or
qualifications as have been obtained under the Securities Act and as may be
required under state securities or Blue Sky laws in connection with the purchase
and distribution of the Shares by the Underwriters as to which such counsel need
express no opinion;

                           (xiv) the Company is not and, after giving effect to
the offering and sale of the Shares, will not be an "investment company" or
entity "controlled" by an "investment company", as such terms are defined in the
Investment Company Act;

                           (xv) Intentionally omitted.

                           (xvi) each of the Company and its subsidiaries owns,
possesses or has obtained all licenses, permits, certificates, consents, orders,
approvals and other authorizations (including licenses, pharmacy licenses,
accreditation and other similar documentation or approvals of any foreign,
federal, state or local health departments) (collectively "Governmental
Licenses") from, and has made all declarations and filings with, all federal,
state, local and other governmental authorities (including foreign regulatory
agencies), all self-regulatory organizations and all courts and other tribunals,
domestic or foreign, necessary to own or lease, as the case may be, and to
operate its properties and to carry on its business as conducted as of the date
hereof, including without limitation, licenses as are required by the FDA or
under the Federal Food, Drug and Cosmetic Act, except where the failure to
obtain such Government Licenses would not reasonably be expected to have a
Material Adverse Effect; the Company and its subsidiaries are in compliance with
the terms and conditions of all such Governmental Licenses and all applicable
FDA rules and regulations, guidelines and policies, except where the failure to
comply would not reasonably be expected to have a Material Adverse Effect and
neither the Company nor any such subsidiary has received any actual notice of
any proceeding relating to revocation or modification of any such Governmental
License, except as described in the Registration Statement and the Prospectus;
and each of the Company and its subsidiaries is in compliance with all laws and
regulations relating to



                                       21
<PAGE>

the conduct of its business as conducted as of the date of the Prospectus,
except where the failure to comply would not reasonably be expected to have a
Material Adverse Effect;

                           (xvii) the Company and its subsidiaries have good and
marketable title to all personal property, (other than Intellectual Property
with respect to which we understand you are receiving the opinion of Fish &
Neave or Yankwich Associates), owned by them which is necessary to operate their
businesses as currently conducted, in each case free and clear of all liens,
encumbrances and defects except such as are described or referred to in the
Prospectus or such as do not materially affect the value of such property and do
not interfere with the use made and proposed to be made of such property by the
Company and its subsidiaries; and any real property and buildings held under
lease by the Company and its subsidiaries are held by them under valid, existing
and enforceable leases with such exceptions as are not material and do not
interfere with the use made or proposed to be made of such property and
buildings by the Company or its subsidiaries; and

                           (xviii) to the knowledge of such counsel, each of the
Company and its subsidiaries is in compliance with all Environmental Laws,
except, in each case, where noncompliance, individually or in the aggregate,
would not have a material adverse effect on the Company and its subsidiaries
taken as a whole; to the knowledge of such counsel, there are no legal or
governmental proceedings pending or threatened against or affecting the Company
or any of its subsidiaries under any Environmental Law which, individually or in
the aggregate, could reasonably be expected to have a material adverse effect on
the Company and its subsidiaries taken as a whole.

         In rendering such opinions, such counsel may rely (A) as to matters
involving the application of laws other than the laws of the United States and
the General Corporation Law of the State of Delaware and the laws of the
Commonwealth of Massachusetts, to the extent such counsel deems proper and to
the extent specified in such opinion, if at all, upon an opinion or opinions (in
form and substance reasonably satisfactory to Underwriters' counsel) of other
counsel reasonably acceptable to the Underwriters' counsel, familiar with the
applicable laws; (B) as to matters of fact, to the extent such counsel deems
proper, on certificates of responsible officers of the Company and certificates
or other written statements of officials of jurisdictions having custody of
documents respecting the corporate existence or good standing of the Company.
The opinion of such counsel for the Company shall state that the opinion of any
such other counsel upon which they relied is in form satisfactory to such
counsel and, in such counsel's opinion, the Underwriters and they are justified
in relying thereon. With respect to the matters to be covered in subparagraph
(x) above counsel may state their opinion and belief is based upon their
participation in the preparation of the Registration Statement and the
Prospectus and any amendment or supplement thereto and review and discussion of
the contents thereof but is without independent check or verification except as
specified.



                                       22
<PAGE>

         The opinion of Palmer & Dodge LLP described above shall be rendered to
the Underwriters at the request of the Company and shall so state therein.

                  (g) Fish & Neave and Yankwich Associates, special intellectual
property and patent counsels for the Company, shall have furnished to the
Representatives their written opinion, dated the Closing Date or the Additional
Closing Date, as the case may be, in form and substance satisfactory to the
Representatives, a form of which is attached hereto as Exhibit A;

                  (h) on the effective date of the Registration Statement and
the effective date of the most recently filed post-effective amendment to the
Registration Statement and also on the Closing Date or Additional Closing Date,
as the case may be, PricewaterhouseCoopers, LLP shall have furnished to you
letters, dated the respective dates of delivery thereof, in form and substance
satisfactory to you, containing statements and information of the type
customarily included in accountants' "comfort letters" to underwriters with
respect to the financial statements and certain financial information contained
in the Registration Statement and the Prospectus;

                  (i) the Representatives shall have received on and as of the
Closing Date or Additional Closing Date, as the case may be, an opinion of
Debevoise & Plimpton, counsel to the Underwriters, with respect to the due
authorization and valid issuance of the Shares, the Registration Statement, the
Prospectus and other related matters as the Representatives may reasonably
request, and such counsel shall have received such papers and information as
they may reasonably request to enable them to pass upon such matters;

                  (j) the Shares to be delivered on the Closing Date or
Additional Closing Date, as the case may be, shall have been approved for
listing on the Nasdaq National Market, subject to official notice of issuance;

                  (k) on or prior to the Closing Date or Additional Closing
Date, as the case may be, the Company shall have furnished to the
Representatives such further certificates and documents as the Representatives
shall reasonably request;

                  (l) the "lock-up" agreements, each substantially in the form
of Exhibit A hereto, between you and each of (i) the existing shareholders, (ii)
officers and (iii) directors of the Company relating to sales and certain other
dispositions of shares of Stock or certain other securities, delivered to you on
or before the date hereof, shall be in full force and effect on the Closing Date
or Additional Closing Date, as the case may be;

                  (m) on or prior to the Closing Date, the Company's
shareholders shall have approved an amendment to the Company's Registration
Rights Agreement, the terms of which are reasonably satisfactory to the
underwriters, permitting the Company



                                       23
<PAGE>

to place a stop order on each share subject to the terms of the Registration
Rights Agreement for a period of 180 days, and the Company shall have made the
appropriate arrangements to execute such stop order on the Closing Date;

                  (n) Intentionally omitted

7. The Company agrees to indemnify and hold harmless each Underwriter and each
person, if any, who controls any Underwriter within the meaning of either
Section 15 of the Securities Act or Section 20 of the Exchange Act, from and
against any and all losses, claims, damages and liabilities (including, without
limitation, the legal fees and other expenses incurred in connection with any
suit, action or proceeding or any claim asserted) caused by any untrue statement
or alleged untrue statement of a material fact contained in the Registration
Statement or the Prospectus (as amended or supplemented if the Company shall
have furnished any amendments or supplements thereto) or any preliminary
prospectus, or caused by any omission or alleged omission to state therein a
material fact required to be stated therein or necessary to make the statements
therein not misleading, except (i) insofar as such losses, claims, damages or
liabilities are caused by any untrue statement or omission or alleged untrue
statement or omission made in reliance upon and in conformity with information
relating to any Underwriter furnished to the Company in writing by such
Underwriter through the Representatives expressly for use therein and (ii) the
indemnity contained in this first paragraph of Section 7 with respect to any
preliminary Prospectus shall not inure to the benefit of any Underwriter from
whom the person asserting any such losses, claims, damages, liabilities or
expenses purchased the Stock which is the subject thereof (or to the benefit of
any person controlling such Underwriter) if, at or prior to the written
confirmation of the sale of such Stock, a copy of the Prospectus (or the
Prospectus as amended or supplemented) was not sent or delivered to such person
and the untrue statement or omission of material fact contained in such
preliminary Prospectus was corrected in such Prospectus (or the Prospectus as
amended or supplemented) unless the failure is the result of the non-compliance
by the Company with the provisions of Section 5(e) hereof. The Company shall
bear the burden of proving that it is not required to indemnify any underwriter
under the provisions of Section 7(ii).

         The Company agrees to indemnify and hold harmless each of the
Underwriters and each person, if any, who controls an Underwriter within the
meaning of either Section 15 of the Securities Act or Section 20 of the Exchange
Act (the "Entities"), from and against any and all losses, claims, damages and
liabilities (including, without limitation, any legal or other expenses
reasonably incurred in connection with defending or investigating any such
action or claim) (i) caused by any untrue statement or alleged untrue statement
of a material fact contained in any material prepared by or with the consent of
the Company for distribution to Participants in connection with the Directed
Share Program or caused by any omission or alleged omission to state therein a
material fact required to be stated therein or necessary to make the statements
therein not



                                       24
<PAGE>

misleading; (ii) caused by the failure of any Participant to pay for and accept
delivery of Directed Shares that the Participant agreed to purchase; or (iii)
related to, arising out of, or in connection with the Directed Share Program,
other than losses, claims, damages or liabilities (or expenses relating thereto)
that are finally judicially determined to have resulted from the bad faith or
gross negligence of the Entities.

         Each Underwriter agrees, severally and not jointly, to indemnify and
hold harmless the Company, its directors, its officers who sign the Registration
Statement and each person who controls the Company within the meaning of Section
15 of the Securities Act and Section 20 of the Exchange Act to the same extent
as the foregoing indemnity from the Company to each Underwriter, but only with
reference to information relating to such Underwriter furnished to the Company
in writing by such Underwriter through the Representatives expressly for use in
the Registration Statement, the Prospectus, any amendment or supplement thereto,
or any preliminary prospectus.

         If any suit, action, proceeding (including any governmental or
regulatory investigation), claim or demand shall be brought or asserted against
any person in respect of which indemnity may be sought pursuant to any of the
three preceding paragraphs, such person (the "Indemnified Person") shall
promptly notify the person against whom such indemnity may be sought (the
"Indemnifying Person") in writing, and the Indemnifying Person, upon request of
the Indemnified Person, shall retain counsel reasonably satisfactory to the
Indemnified Person to represent the Indemnified Person and any others the
Indemnifying Person may designate in such proceeding and shall pay the fees and
expenses of such counsel related to such proceeding. In any such proceeding, any
Indemnified Person shall have the right to retain its own counsel, but the fees
and expenses of such counsel shall be at the expense of such Indemnified Person
PROVIDED that the Indemnifying Person shall pay all fees and expenses of one
counsel if (i) the Indemnifying Person and the Indemnified Person shall have
mutually agreed, (ii) the Indemnifying Person has failed within a reasonable
time to retain counsel reasonably satisfactory to the Indemnified Person or
(iii) the named parties in any such proceeding (including any impleaded parties)
include both the Indemnifying Person and the Indemnified Person and based upon
the advice of counsel for the Indemnified Person (which may be in-house
counsel), whether or not the counsel referred to above, representation of both
parties by the same counsel would be inappropriate due to actual or potential
differing interests between them, in which case counsel for the Indemnified
Party shall be entitled to conduct the defense to the extent necessary to
protect the interests of the Indemnified Party. It is understood that the
Indemnifying Person shall not, in connection with any proceeding or related
proceeding in the same jurisdiction, be liable for the fees and expenses of more
than one separate firm (in addition to any local counsel) for all Indemnified
Persons, and that all such fees and expenses shall be reimbursed as they are
incurred. Any such separate firm for the Underwriters and such control persons
of Underwriters shall be designated in writing by J.P. Morgan Securities Inc.
and any such separate firm for the Company, its directors, its officers who sign
the



                                       25
<PAGE>

Registration Statement and such control persons of the Company shall be
designated in writing by the Company. Notwithstanding anything contained herein
to the contrary, if indemnity may be sought pursuant to the second paragraph of
this Section 7 in respect of such action or proceeding, then in addition to such
separate firm for the Indemnified Persons, the Indemnifying Person shall be
liable for the reasonable fees and expenses of not more than one separate firm
(in addition to any local counsel), such counsel to be designated by J.P.
Morgan, for the Underwriters for the defense of any losses, claims, damages and
liabilities arising out of the Directed Share Program, and all other damages and
liabilities arising out of the Directed Share Program, and all other persons, if
any, who control either of the Underwriters within the meaning of either Section
15 of the Securities Act or Section 20 of the Exchange Act. The Indemnifying
Person shall not be liable for any settlement of any proceeding effected without
its written consent, but if settled with such consent or if there be a final
judgment for the plaintiff, the Indemnifying Person agrees to indemnify any
Indemnified Person from and against any loss or liability by reason of such
settlement or judgment. Notwithstanding the foregoing sentence, if at any time
an Indemnified Person shall have requested an Indemnifying Person to reimburse
the Indemnified Person for fees and expenses of counsel as contemplated by the
second and third sentences of this paragraph, the Indemnifying Person agrees
that it shall be liable for any settlement of any proceeding effected without
its written consent if (i) such settlement is entered into more than 30 days
after receipt by such Indemnifying Person of the aforesaid request and (ii) such
Indemnifying Person shall not have reimbursed the Indemnified Person in
accordance with such request prior to the date of such settlement. No
Indemnifying Person shall, without the prior written consent of the Indemnified
Person, effect any settlement of any pending or threatened proceeding in respect
of which any Indemnified Person is or could have been a party and indemnity
could have been sought hereunder by such Indemnified Person, unless such
settlement includes an unconditional release of such Indemnified Person from all
liability on claims that are the subject matter of such proceeding.

         If the indemnification provided for in the first, second or third
paragraphs of this Section 7 is unavailable to an Indemnified Person or
insufficient in respect of any losses, claims, damages or liabilities referred
to therein, then each Indemnifying Person under such paragraph, in lieu of
indemnifying such Indemnified Person thereunder, shall contribute to the amount
paid or payable by such Indemnified Person as a result of such losses, claims,
damages or liabilities (i) in such proportion as is appropriate to reflect the
relative benefits received by the Company on the one hand and the Underwriters
on the other hand from the offering of the Shares or (ii) if the allocation
provided by clause (i) above is not permitted by applicable law, in such
proportion as is appropriate to reflect not only the relative benefits referred
to in clause (i) above but also the relative fault of the Company on the one
hand and the Underwriters on the other hand in connection with the statements or
omissions that resulted in such losses, claims, damages or liabilities, as well
as any other relevant equitable considerations. The relative benefits received
by the Company on the one hand and the Underwriters on the other hand shall be
deemed to be



                                       26
<PAGE>

in the same respective proportions as the net proceeds from the offering (before
deducting expenses) received by the Company and the total underwriting discounts
and the commissions received by the Underwriters, in each case as set forth in
the table on the cover of the Prospectus, bear to the aggregate public offering
price of the Shares. The relative fault of the Company on the one hand and the
Underwriters on the other hand shall be determined by reference to, among other
things, whether the untrue or alleged untrue statement of a material fact or the
omission or alleged omission to state a material fact relates to information
supplied by the Company or by the Underwriters and the parties' relative intent,
knowledge, access to information and opportunity to correct or prevent such
statement or omission.

         The Company and the Underwriters agree that it would not be just and
equitable if contribution pursuant to this Section 7 were determined by PRO RATA
allocation (even if the Underwriters were treated as one entity for such
purposes) or by any other method of allocation that does not take account of the
equitable considerations referred to in the immediately preceding paragraph. The
amount paid or payable by an Indemnified Person as a result of the losses,
claims, damages and liabilities referred to in the immediately preceding
paragraph shall be deemed to include, subject to the limitations set forth
above, any legal or other expenses incurred by such Indemnified Person in
connection with investigating or defending any such action or claim.
Notwithstanding the provisions of this Section 7, in no event shall the Company
be required to contribute or make any payment under this Section 7 which in the
aggregate exceed the payments which the Company would otherwise have been
obligated to make under the first and second paragraphs of this Section 7 had
the indemnification provided for in such first and second paragraphs been
available, and in no event shall an Underwriter be required to contribute any
amount in excess of the amount by which the total price at which the Shares
underwritten by it and distributed to the public were offered to the public
exceeds the amount of any damages that such Underwriter has otherwise been
required to pay by reason of such untrue or alleged untrue statement or omission
or alleged omission. No person guilty of fraudulent misrepresentation (within
the meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation. The Underwriters' obligations to contribute pursuant to this
Section 7 are several in proportion to the respective number of Shares set forth
opposite their names in Schedule I hereto, and not joint.

         The remedies provided for in this Section 7 are not exclusive and shall
not limit any rights or remedies which may otherwise be available to any
indemnified party at law or in equity.

         The indemnity and contribution agreements contained in this Section 7
and the representations and warranties of the Company set forth in this
Agreement shall remain operative and in full force and effect regardless of (i)
any termination of this Agreement, (ii) any investigation made by or on behalf
of any Underwriter or any person controlling



                                       27
<PAGE>

any Underwriter or by or on behalf of the Company, its officers or directors or
any other person controlling the Company and (iii) acceptance of and payment for
any of the Shares.

         8. Notwithstanding anything herein contained, this Agreement (or the
obligations of the several Underwriters with respect to the Option Shares) may
be terminated in the absolute discretion of the Representatives, by notice given
to the Company, if after the execution and delivery of this Agreement and prior
to the Closing Date (or, in the case of the Option Shares, prior to the
Additional Closing Date) (i) trading generally shall have been suspended or
materially limited on or by, as the case may be, any of the New York Stock
Exchange, the American Stock Exchange or the Nasdaq National Market, (ii)
trading of any securities of or guaranteed by the Company shall have been
suspended on any exchange or in any over-the-counter market, (iii) a general
moratorium on commercial banking activities in New York shall have been declared
by either Federal or New York State authorities, or (iv) there shall have
occurred any outbreak or escalation of hostilities or any change in financial
markets or any calamity or crisis that, in the reasonable judgment of the
Representatives, is material and adverse and which, in the reasonable judgment
of the Representatives, makes it impracticable to market the Shares being
delivered at the Closing Date or the Additional Closing Date, as the case may
be, on the terms and in the manner contemplated in the Prospectus.

         9. This Agreement shall become effective upon the later of (x)
execution and delivery hereof by the parties hereto and (y) release of
notification of the effectiveness of the Registration Statement (or, if
applicable, any post-effective amendment) by the Commission.

         If on the Closing Date or the Additional Closing Date, as the case may
be, any one or more of the Underwriters shall fail or refuse to purchase Shares
which it or they have agreed to purchase hereunder on such date, and the
aggregate number of Shares which such defaulting Underwriter or Underwriters
agreed but failed or refused to purchase is not more than one-tenth of the
aggregate number of Shares to be purchased on such date, the other Underwriters
shall be obligated severally in the proportions that the number of Shares set
forth opposite their respective names in Schedule I bears to the aggregate
number of Underwritten Shares set forth opposite the names of all such
non-defaulting Underwriters, or in such other proportions as the Representatives
may specify, to purchase the Shares which such defaulting Underwriter or
Underwriters agreed but failed or refused to purchase on such date; PROVIDED
that in no event shall the number of Shares that any Underwriter has agreed to
purchase pursuant to Section 1 be increased pursuant to this Section 9 by an
amount in excess of one-tenth of such number of Shares without the written
consent of such Underwriter. If on the Closing Date or the Additional Closing
Date, as the case may be, any Underwriter or Underwriters shall fail or refuse
to purchase Shares which it or they have agreed to purchase hereunder on such
date, and the



                                       28
<PAGE>

aggregate number of Shares with respect to which such default occurs is more
than one-tenth of the aggregate number of Shares to be purchased on such date,
and arrangements satisfactory to the Representatives and the Company for the
purchase of such Shares are not made within 36 hours after such default, this
Agreement (or the obligations of the several Underwriters to purchase the Option
Shares, as the case may be) shall terminate without liability on the part of any
non-defaulting Underwriter or the Company. In any such case either you or the
Company shall have the right to postpone the Closing Date or, in the case of the
Option Shares, the Additional Closing Date, but in no event for longer than
seven days, in order that the required changes, if any, in the Registration
Statement and in the Prospectus or in any other documents or arrangements may be
effected. Any action taken under this paragraph shall not relieve any defaulting
Underwriter from liability in respect of any default of such Underwriter under
this Agreement.

         10. If this Agreement shall be terminated by the Underwriters, or any
of them, because of any failure or refusal on the part of the Company to comply
with the terms or to fulfill any of the conditions of this Agreement, or if for
any reason the Company shall be unable to perform its obligations under this
Agreement or any condition of the Underwriters' obligations cannot be fulfilled,
the Company agrees to reimburse the Underwriters or such Underwriters as have so
terminated this Agreement with respect to themselves, severally, for all
out-of-pocket expenses (including the fees and expenses of its counsel)
reasonably incurred by the Underwriter in connection with this Agreement or the
offering contemplated hereunder.

         11. This Agreement shall inure to the benefit of and be binding upon
the Company, the Underwriters, any controlling persons referred to herein and
their respective successors and assigns. Nothing expressed or mentioned in this
Agreement is intended or shall be construed to give any other person, firm or
corporation any legal or equitable right, remedy or claim under or in respect of
this Agreement or any provision herein contained. No purchaser of Shares from
any Underwriter shall be deemed to be a successor by reason merely of such
purchase.

         12. Any action by the Underwriters hereunder may be taken by the
Representatives jointly or by J.P. Morgan Securities Inc. alone on behalf of the
Underwriters, and any such action taken by the Representatives jointly or by
J.P. Morgan Securities Inc. alone shall be binding upon the Underwriters. All
notices and other communications hereunder shall be in writing and shall be
deemed to have been duly given if mailed or transmitted by any standard form of
telecommunication. Notices to the Underwriters shall be given to the
Representatives, c/o J.P. Morgan Securities Inc., 60 Wall Street, New York, New
York 10260 (telefax:______); Attention: Syndicate Department, with a copy to
Debevoise & Plimpton, 875 Third Avenue, New York, New York 10022 (telefax
(212)-909-6836); Attention of Michael W. Blair. Notices to the Company shall be
given to it at One Kendall Square, Cambridge, Massachusetts, 02139, Attention of
Henry E. Blair, President and Chief Executive Officer, with a copy to



                                       29
<PAGE>

Palmer & Dodge LLP, One Beacon Street, Boston, Massachusetts, 02108, (telefax:
617-227-4420); Attention: Nathaniel S. Gardiner.

         13. This Agreement may be signed in counterparts, each of which shall
be an original and all of which together shall constitute one and the same
instrument.

         14. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE
WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT GIVING EFFECT TO THE CONFLICTS
OF LAWS PROVISIONS THEREOF.



                                       30
<PAGE>

         If the foregoing is in accordance with your understanding, please sign
and return four counterparts hereof.

                                        Very truly yours,

                                        DYAX CORP.

                                        By: _____________________________
                                            Name:

                                            Title:

Accepted:_________, 2000

J.P. Morgan Securities Inc.
Lehman Brothers
Pacific Growth Equities, Inc.

Acting severally on behalf
  of themselves and the
  several Underwriters listed
  in Schedule I hereto.

By:  J.P. Morgan Securities Inc.
Acting on behalf of itself and the
several Underwriters listed in
Schedule I hereto.

By: ____________________________________
       Name:
       Title:



                                       31
<PAGE>



                                   SCHEDULE I

<TABLE>
<CAPTION>
UNDERWRITER                                                 NUMBER OF SHARES
                                                            TO BE PURCHASED
<S>                                                         <C>
J.P. Morgan Securities Inc.........................
Lehman Brothers....................................
Pacific Growth Equities, Inc.......................

                                   Total
                                                          ==================
</TABLE>


<PAGE>

                                    Exhibit A

                          FORM OF OPINION OF COMPANY'S
                      SPECIAL INTELLECTUAL PROPERTY COUNSEL
                            PURSUANT TO SECTION 5(g)

                  (a) To the best of our knowledge, the Company and each of its
Subsidiaries owns or possesses or can acquire on reasonable terms, all
Intellectual Property currently employed by them in connection with the business
now operated by them except where the failure to own or possess or otherwise be
able to acquire such Intellectual Property could not, singly or in the
aggregate, have a Material Adverse Effect.

                  (b) Based upon a review of the third-party rights made known
to us and our discussions with personnel of the Company, we are not aware of any
United States or foreign patent, that is or would be infringed by the activities
of the Company in the conduct of its business as described in the Prospectus.

                  (c) We have reviewed the Company patent applications which are
identified in the Patent Schedule included with this letter, and in our opinion
the Company's patent applications have been properly prepared and filed, and are
being diligently pursued by the Company, and the inventions described in the
Company patent applications are owned by, have been assigned to or are licensed
to the Company.

                  (d) To our knowledge, except as specifically disclosed in the
Prospectus, no party or individual has any right or claim in any of the
inventions, patents or patent applications listed in the Patent Schedule.

                  (e) To the best of our knowledge each of the Company's patent
applications discloses patentable subject matter and each of the Company's
patent applications would reasonably be expected to withstand the heightened
scrutiny given to business method patents by the United States Patent and
Trademark office.

                  (f) To the best of our knowledge, the Company is not
infringing or otherwise violating any Intellectual Property of others. To the
best of our knowledge, the Company has not received any notice of infringement
of or conflict with asserted rights of others with respect to any Intellectual
Property.

                  (g) We know of no legal or governmental proceedings that are
pending or, to the best of our knowledge, that are threatened, relating to any
Intellectual Property, other than litigation identified in the Litigation
Schedule included with this letter.

                                       2

<PAGE>

                  (h) The information in the Prospectus under "Risk Factors -
Our success depends significantly upon our ability to obtain and maintain
intellectual property protection for our products and technologies," "Risk
Factors - Proceedings to obtain, enforce or defend patents and to defend against
charges of infringement are time consuming and expensive activities. Unfavorable
outcomes in these proceedings could limit our patent rights and our activities,
which could materially affect our business," "Business - Collaborations and
Licenses," "Business - Patents and Proprietary Rights" and "Business - Legal
Proceedings" (collectively, the "Intellectual Property Disclosure"), to the
extent that it constitutes matters of law, summaries of legal matters or legal
proceedings, or legal conclusions, has been reviewed by us and is correct in all
material respects.

         Nothing has come to our attention that would lead us to believe that
the Intellectual Property Disclosure in the Registration Statement or any
amendment thereto, including the Rule 430A Information and Rule 434 Information
(if applicable), at the time such Registration Statement or any such amendment
became effective, contained an untrue statement of a material fact or omitted to
state a material fact required to be stated therein or necessary to make the
statements therein not misleading or that the Intellectual Property Disclosure
in the Prospectus or any amendment or supplement thereto, at the time the
Prospectus was issued, at the time any such amended or supplemented prospectus
was issued or at the Closing Time, included or includes an untrue statement of a
material fact or omitted or omits to state a material fact necessary in order to
make the statements therein, in the light of the circumstances under which they
were made, not misleading.

         In rendering such opinion, such counsel may rely as to matters of fact
(but not as to legal conclusions), to the extent they deem proper, on
certificates of responsible officers of the Company and public officials. Such
opinion shall not state that it is to be governed or qualified by, or that it is
otherwise subject to, any treatise, written policy or other document relating to
legal opinions, including, without limitation, the Legal Opinion Accord of the
ABA Section of Business Law (1991).


                                       3