Exhibit 1.1



March 13, 2003

Henry E. Blair
Chairman and CEO
Dyax Corp.
300 Technology Square
Cambridge, MA 02139

Dear Henry:

     This is to confirm the agreement (the "Agreement") between Pacific Growth
Equities, Inc. ("PGE") and DYAX Corp. ("the Company") as follows:

1.  SERVICES TO BE RENDERED. The Company hereby retains PGE as the Company's
    exclusive placement agent in connection with the placement (the
    "Placement") by the Company of up to 5,000,000 shares of common stock (the
    "Shares"). PGE agrees that it will exercise its commercially reasonable
    efforts to find suitable purchasers of the Shares. Prior to soliciting any
    investors, PGE shall notify the Company and receive the Company's oral
    permission to approach such investors (the "Designated Investors"). It is
    understood that the decision to proceed with, and the final terms of, the
    Placement will depend on satisfactory results of PGE's due diligence
    investigation (including reviews of legal, accounting and operational
    issues) of the Company's continuing business prospects and the prevailing
    securities market conditions at the time of the Placement. It is anticipated
    that the Placement process will commence promptly. PGE disclaims any
    agreement, expressed or implied, in this Agreement or otherwise, that it
    will be successful in placing the Shares.

2.  OFFERING MATERIALS.  The Company will provide to PGE copies of the
    prospectus dated May 3, 2002 contained in the registration statement on
    Form S-3 dated April 24, 2002 (Registration No. 333-86904) (the Registration
    Statement") and, when available, copies of the prospectus supplement issued
    in connection with the Placement (and any amendments or supplements thereto)
    which will be provided to potential purchasers of the Shares (the "Offering
    Materials"). The Company represents that the Offering Materials will not
    (when read together), as of the final closing date of the Placement (the
    "Closing Date"), contain any untrue statement of material fact or omit to
    state any material fact required to be stated therein, or necessary to make
    the statements contained therein, in light of the circumstances under which
    they were made, not misleading. The Company agrees to cooperate with PGE in
    connection with the offering of the Shares, including making appropriate
    officers or principals of the Company available to PGE for meetings with
    prospective purchasers of the Shares. The Company and PGE will prepare
    definitive transaction documents for use in the Placement, including a
    Common Stock Purchase Agreement, which shall be in form and substance
    reasonably satisfactory to PGE.



HENRY E. BLAIR
Page 2


    PGE recognizes and acknowledges that it is not authorized to make any
    representations and statements to any potential purchaser other than and to
    the extent that such representations and statements are contained in the
    Offering Materials or otherwise have been made by the Company to PGE with
    the intent and expectation that they be made to potential purchasers.

3.  REPRESENTATIONS AND WARRANTIES OF THE COMPANY. The Company represents,
    warrants and agrees that:

    a. Except for the issuance of stock options and common stock issuable upon
       exercise of outstanding options and warrants, the Company will not, from
       the date of this letter until the final closing of the Placement or the
       termination of this Agreement before such a closing, offer to sell,
       solicit offers to purchase, or sell any securities of the Company without
       PGE's written consent;

    b. The issuance of all of the Shares has been registered on the Registration
       Statement and, as of the Closing Date, the Shares will be listed on the
       Nasdaq National Market. In connection with the transactions contemplated
       by this Agreement, the Company will make any and all required filings
       under any and all applicable federal and state securities laws;

    c. The Company has all requisite corporate power and authority to execute
       and perform this Agreement. All corporate action necessary for the
       authorization, execution, delivery and performance of this Agreement has
       been taken. This Agreement constitutes a valid and binding obligation of
       the Company; and

    d. The execution and performance of this Agreement by the Company and the
       offer and sale of the Shares in the Placement will not violate any
       provision of the articles of incorporation or bylaws of the Company or
       any agreement or other instrument to which the Company is a party or by
       which it is bound. Any necessary approvals, governmental and private,
       will be obtained by the Company prior to the closing.

4.  EXPIRATION OF ENGAGEMENT. The engagement of PGE as placement agent under
    Section 1 shall expire on the Closing Date. The expiration of such
    engagement shall not affect the other provisions of this Agreement, all of
    which shall remain in effect.

5.  PLACEMENT AGENT FEES. In consideration for the services rendered by PGE
    hereunder, the Company agrees to pay PGE on the Closing Date, a COMMISSION
    of 6.62% of the gross proceeds to the Company on all sales of Shares made in
    the Placement, other than sales of Shares to Loeb Partners. The Company and
    PGE agree that no commission will be paid on sales of Shares to Loeb
    Partners. In addition, the Company agrees to reimburse PGE for all
    reasonable out-of-pocket expenses incurred by PGE in connection with the
    Placement including the reasonable fees and expenses of PGE's counsel, up to
    a maximum of $10,000.




HENRY E. BLAIR
Page 3

6.  TRANSACTION EXPENSES. Except as provided in Section 5 hereto, the Company
    agrees to bear all of the expenses associated with the transactions
    contemplated by this Agreement, including, without limitation, all printing
    and mailing costs, all blue sky fees and costs (if any) and the fees and
    costs of Company's counsel.

7.  OBLIGATIONS LIMITED. PGE shall be under no obligation hereunder to make an
    independent appraisal of assets or investigation or inquiry as to any
    information regarding, or any representations of, the Company and shall have
    no liability hereunder in regard thereto.

8.  INDEMNIFICATION. The Company agrees to indemnify and hold harmless PGE, its
    members, affiliates, agents, servants and employees and each person, if any,
    who controls PGE within the meaning of section 20(a) of the SECURITIES
    Exchange Act of 1934 (the "Exchange Act"), against any and all loss,
    liability, claim, damage and expenses reasonably incurred by each
    or any of them in investigations, preparing to defend or defending against
    any such action, proceeding or claim (whether commenced or threatened) or in
    connection with any investigation or inquiry (i) arising out of, related to
    or based upon any untrue or alleged untrue statement of a material fact or
    the omission or alleged omission of a material fact required to be stated or
    necessary to make not misleading any statements contained in the Offering
    Materials or the Common Stock Purchase Agreement and/or (ii) otherwise
    arising out of, related to or based upon any acts or omissions of the
    Company, its directors, officers, employees, affiliates and/or agents (other
    than PGE) in connection with the transactions contemplated by this
    Agreement; PROVIDED, HOWEVER, that the Company will not be liable under this
    Section 8(a) to the extent that any such loss, claim, damage or liability
    arises out of or is based upon an untrue statement or alleged untrue
    statement or omission or alleged omission made in the Offering Materials in
    reliance upon and in conformity with written information furnished to the
    Company by PGE specifically for use therein. This indemnity shall be in
    addition to any liability the Company may have to PGE otherwise. The Company
    agrees promptly to notify PGE of the commencement of any litigation or
    proceedings against the Company or any of its officers, director, employees,
    affiliates and/or agents in connection with the Placement of the Shares or
    in connection with the Offering Materials.

    If any action, claim or investigation (collectively, a "Claim") is brought
    against an indemnified party, then such party promptly shall notify the
    indemnifying party in writing of such action. Failure by such person to so
    notify the indemnifying party shall not relieve the indemnifying party from
    its obligation to indemnify, except to the extent that such failure to
    notify results in the forfeiture by the indemnifying party of substantive
    rights or defenses. If an indemnified party seeks indemnification hereunder
    with respect to any Claim brought by a third party, the indemnifying party
    shall be entitled to assume the defense of such Claim, such indemnified
    party shall have the right to participate in the defense of such Claim and
    to retain its own counsel but the indemnifying party shall not be liable for
    any legal fees or expenses subsequently incurred by such indemnified party
    in connection with the defense thereof, unless (i) the indemnifying party
    has agreed to pay such fees and expenses, (ii) the indemnifying party shall
    have failed to employ counsel reasonably satisfactory to such indemnified
    party in a timely manner or (iii) such indemnified party shall have
    reasonably determined that representation of such indemnified party by
    counsel provided by the indemnifying party pursuant to the foregoing would
    be inappropriate due to actual or potential conflicting interests between




HENRY E. BLAIR
Page 4


    the indemnifying party and such indemnified party, including without
    limitation in the event the indemnified party shall have reasonably
    determined that there are legal defenses available to the indemnified party
    which are different from or additional to those available to the
    indemnifying party. The indemnifying party shall not be liable for any
    settlement or any Claim effected without its written consent (which consent
    shall not be unreasonably withheld or delayed).

9.  ENTIRE AGREEMENT AND GOVERNING LAW. This Agreement sets forth the entire
    understanding of the parties and supersedes any prior communications,
    understanding and agreements BETWEEN the parties. This Agreement cannot be
    changed, nor can any of its provisions be waived, except by writing signed
    by all parties. This Agreement shall be governed by the laws of the State of
    California without regard to its conflict of laws provisions.

10. TERMINATION. This Agreement may be terminated by either party at any time
    prior to the Closing Date of the Placement upon written notice to the other
    party.

11. SURVIVAL. The provisions of Sections 5 (including the Company's obligation
    to reimburse PGE for its out-of-pocket expenses) and 8 hereof shall survive
    any termination of this Agreement; provided that the Company's obligation to
    pay fees to PGE pursuant to Section 5 shall not survive any termination of
    this Agreement prior to the Closing Date of the Placement by PGE other than
    due to the Company's breach of any term of this Agreement or the Company's
    failure to satisfy a condition to closing.

12. NOTICES. Any notice, consent or other communication given pursuant to this
    Agreement shall be in writing and shall be effective when (i) delivered
    personally, (ii) sent by telex or telecopier (with RECEIPT confirmed),
    provided that a copy is mailed registered mail, return receipt requested, or
    (iii) when received by the addressee, if sent by Express Mail, Federal
    Express or other express delivery service (receipt requested), in each case
    to the appropriate addressee set forth below:


            If to PGE:  Pacific Growth Equities, Inc.
                        Four Maritime Plaza
                        San Francisco, CA 94111
                        Attn: George J. Milstein

    If to the Company:  Henry E. Blair
                        Chairman & CEO
                        300 Technology Square
                        Cambridge, MA 02139




HENRY E. BLAIR
Page 5


         If the foregoing correctly sets forth your understanding, please so
indicate by signing and returning to us the enclosed copy of this letter.

Sincerely,

PACIFIC GROWTH EQUITIES, INC.

  By: /s/ George J. Milstein                  Date: March 13, 2003
     ------------------------------------          -----------------------------
     George J. Milstein
     Senior Managing Director


Confirmed and Agreed to:




COMPANY


  By: /s/ Henry E. Blair                      Date: March 13, 2003
     ------------------------------------          -----------------------------
     Henry E. Blair
     Chairman & Chief Executive Officer