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                                                                   Exhibit 10.11

                        AMENDMENT TO EMPLOYMENT AGREEMENT

      This Amendment (the "Amendment"), effective as of August 25, 2003 (the
"Effective Date"), to the employment agreement executed on April 12, 2000 (the
"Employment Agreement") by and between Eyetech Pharmaceuticals, Inc., a Delaware
corporation (the "Company"), and David Guyer, an individual (the "Executive").

                                   WITNESSETH:

      WHEREAS, the Company and the Executive entered into the Employment
Agreement; and

      WHEREAS, the Company and the Executive desire to amend the Employment
Agreement to reflect changes which the parties hereby agree to in connection
with the Company's continued employment of the Executive;

      NOW, THEREFORE, in consideration of the mutual covenants and agreements
set forth herein and for good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the parties hereto agree as follows:

1.    Amendments - The Employment Agreement shall be amended to include the
      following provisions.

      1.1   Term. This Agreement will remain in force and effect throughout the
            term of the Executive's employment with the Company. Executive's
            employment with the Company may be terminated by either the Company
            or the Executive at any time subject only to the severance
            provisions contained in section 1.2 hereof.

      1.2   Termination and Severance. The Severance payments provided in this
            Amendment shall be the sole payments and benefits for which the
            Executive shall be eligible at the conclusion of his employment with
            the Company for any reason and shall supersede any and all prior
            agreements or arrangements for post-termination benefits.

            (a)   In the event Executive's employment terminates as a result of
                  a voluntary termination by Executive for Good Reason, or a
                  termination by the Company without Cause, upon execution of an
                  effective general release of all claims against the Company,
                  its employees, officers, directors and agents, in a form
                  reasonably acceptable to the Company: (i) Executive shall
                  receive eighteen (18) monthly payments each equal in amount to
                  one-twelfth (1/12th) of Executive's then base salary, less
                  applicable state and federal withholdings; and (ii) for a
                  period of eighteen (18) months (or until comparable benefits
                  coverage becomes available to Executive, if sooner), the
                  Company shall reimburse Executive (or pay him directly, at the
                  Company's option) the costs associated with the continuation
                  of Executive's and his dependents' medical and dental benefits
                  under the Consolidated Omnibus Budget Reconciliation Act of
                  1985, as amended ("COBRA") as in effect immediately prior to
                  Executive's termination of
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                  employment.

            (b)   For purposes of this Agreement, "Good Reason" means that any
                  of the following are undertaken without Executive's express
                  written consent: (i) the assignment to Executive of any duties
                  or responsibilities which result in any material diminution or
                  adverse change of Executive's position, status or
                  circumstances of employment; (ii) the taking of any action by
                  the Company which would adversely affect Executive's
                  participation in, or reduce Executive's benefits under, the
                  Company's benefit plans (including equity benefits) as of the
                  time this Amendment is executed; (iii) a relocation of
                  Executive's principal office to a location more than
                  thirty-five (35) miles from Manhattan, New York, except for
                  required travel by Executive on the Company's business; or
                  (iv) any failure by the Company to obtain the assumption of
                  the Employment Agreement by any successor or assign of the
                  Company. For purposes of this Amendment, "Cause" means: (V) an
                  intentional action or intentional failure to act by Executive
                  which was performed in bad faith and to the material detriment
                  of the Company; (W) Executive intentionally refuses or
                  intentionally fails to act in accordance with any lawful and
                  proper direction or order of the Board; (X) Executive
                  willfully and habitually neglects the duties of his
                  employment; or (Z) Executive is convicted of a felony crime
                  involving moral turpitude; provided, however, that in the
                  event that any of the foregoing events under clauses (V), (W),
                  (X) or (Y) above is capable of being cured, the Company shall
                  provide written notice to Executive describing the nature of
                  such event and Executive shall thereafter have ten (10)
                  business days to cure such event.

            (c)   In the event Executive's employment terminates as a result of
                  termination of Executive by the Company or its successor
                  without Cause, or by the Executive voluntarily for Good
                  Reason, within the three (3) months before or twelve (12)
                  months following a Change in Control Event, upon execution of
                  an effective general release of all claims against the
                  Company, its employees, officers, directors and agents, in a
                  form reasonably acceptable to the Company: (i) Executive shall
                  receive, within fifteen (15) days of such termination, one
                  lump sum payment equivalent to twenty-four (24) months of his
                  then Base Salary, less applicable state and federal
                  withholdings; (ii) Executive's unvested equity rights shall
                  become vested and exercisable as set forth in Section 1.3(b);
                  and (iii) for a period of eighteen (18) months (or until
                  comparable benefits coverage becomes available to Executive,
                  if sooner), the Company shall reimburse Executive (or pay him
                  directly at the Company's option) the costs associated with
                  the continuation of Executive's and his dependents' medical
                  and dental benefits under COBRA as in effect immediately prior
                  to Executive's termination of employment. For purposes of this
                  paragraph, Executive's "Base Salary" shall be the greater of
                  the amount in effect either immediately prior to the Change in
                  Control Event or the termination date of Executive's
                  employment. The benefits provided under this Section




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                  1.2(c) shall be in lieu of any benefits the Executive would
                  have otherwise been entitled to pursuant to Section 1.2(a) of
                  this Agreement.

            (d)   For purposes of this Amendment, a "Change in Control Event"
                  shall mean:

                  (i)   The acquisition by an individual, entity or group
                        (within the meaning of Section 13(d)(3) or 14(d)(2) of
                        the Exchange Act) (a "Person") of beneficial ownership
                        of any capital stock of the Company if, after such
                        acquisition, such Person beneficially owns (within the
                        meaning of Rule 13d-3 promulgated under the Exchange
                        Act) 50% or more of either (x) the then-outstanding
                        shares of common stock of the Company (the "Outstanding
                        Company Common Stock") or (y) the combined voting power
                        of the then-outstanding securities of the Company
                        entitled to vote generally in the election of directors
                        (the "Outstanding Company Voting Securities"); provided
                        however, that for purposes of this subsection (i), the
                        following acquisitions shall not constitute a Change in
                        Control Event: (A) any acquisition directly from the
                        Company (excluding an acquisition pursuant to the
                        exercise, conversion or exchange of any security
                        exercisable for, convertible into or exchangeable for
                        common stock or voting securities of the Company, unless
                        the Person exercising, converting or exchanging such
                        security acquired such security directly from the
                        Company or an underwriter or agent of the Company), (B)
                        any acquisition by any employee benefit plan (or related
                        trust) sponsored or maintained by the Company or any
                        corporation controlled by the Company, or (C) any
                        acquisition by an corporation pursuant to a Business
                        Combination (as defined below) which complies with
                        clauses (x) and (y) of subsection (iii) of this
                        definition; or

                  (ii)  Such time as the Continuing Directors (as defined below)
                        do not constitute a majority of the Board (or, if
                        applicable, the Board of Directors of a successor
                        corporation to the Company), where the term "Continuing
                        Director" means at any date a member of the Board (x)
                        who was a member of the Board on the date of the initial
                        adoption of this Amendment by the Board or (y) who was
                        nominated or elected subsequent to such date by at least
                        a majority of the directors who were Continuing
                        Directors at the time of such nomination or election or
                        whose election to the Board was recommended or endorsed
                        by at least a majority of the directors who were
                        Continuing Directors at the time of such nomination or
                        election; or

                  (iii) The consummation of a merger, consolidation,
                        reorganization, recapitalization or share exchange
                        involving the Company or a sale or other disposition of
                        all or substantially all of the assets of the Company
                        (a "Business Combination"), unless, immediately



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                        following such Business Combination, each of the
                        following two conditions is satisfied: (x) all or
                        substantially all of the individuals and entities who
                        were the beneficial owners of the Outstanding Company
                        Common Stock and Outstanding Company Voting Securities
                        immediately prior to such Business Combination
                        beneficially own, directly or indirectly, more than 50%
                        of the then-outstanding shares of common stock and the
                        combined voting power of the then-outstanding securities
                        entitled to vote generally in the election of directors,
                        respectively, of the resulting or acquiring corporation
                        or other form of entity in such Business Combination
                        (which shall include, without limitation, a corporation
                        which as a result of such transaction owns the Company
                        or substantially all of the Company's assets either
                        directly or through one or more subsidiaries) (such
                        resulting or acquiring corporation or entity is referred
                        to herein as the "Acquiring Corporation") in
                        substantially the same proportions as their ownership of
                        the Outstanding Company Common Stock and Outstanding
                        Company Voting Securities, respectively, immediately
                        prior to such Business Combination and (y) no Person
                        (excluding the Acquiring Corporation or any employee
                        benefit plan (or related trust) maintained or sponsored
                        by the Company or by the Acquiring Corporation)
                        beneficially owns, directly or indirectly, 30% or more
                        of the then-outstanding shares of common stock of the
                        Acquiring Corporation, or of the combined voting power
                        of the then-outstanding securities of such corporation
                        entitled to vote generally in the election of directors
                        (except of the extent that such ownership existed prior
                        to the Business Combination).

                  (iv)  Notwithstanding the foregoing, a Change in Control Event
                        will not be deemed to have occurred in the case of a
                        Management Buy Out. A "Management Buy Out" is any event
                        which would otherwise be deemed a "Change in Control
                        Event", in which the Executive, directly or indirectly
                        (as a beneficial owner) acquires equity securities,
                        including any securities convertible into or
                        exchangeable for equity securities, of the Company or
                        the Acquiring Corporation in connection with any Change
                        in Control Event.

1.3   Treatment of Equity Upon Change in Control Event. Upon a Change in Control
      Event, as defined in Section 1.2(d):

      (a)   50% of all of the Executive's unvested equity rights shall become
            vested and immediately exercisable; and

      (b)   If Executive's employment terminates as result of the circumstances
            outlined in Section 1.2(c), and provided that Executive executes an


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            effective general release as required by Section 1.2(c), 100% of the
            Executive's unvested equity rights shall then become vested and
            immediately exercisable.

1.4   Golden Parachute Taxes. Notwithstanding anything contained in this
      Amendment to the contrary, to the extent that payments and benefits
      provided under this Amendment to Executive and benefits provided to, or
      for the benefit of, Executive under any other Company plan or agreement
      (such payments or benefits are collectively referred to as the "Payments")
      would be subject to the excise tax (the "Excise Tax") imposed under
      Section 4999 of the Internal Revenue Code of 1986, as amended (the
      "Code"), the Payments shall be reduced (but not below zero) to the extent
      necessary so that no Payment to be made or benefit to be provided to the
      Executive shall be subject to the Excise Tax, but only if, by reason of
      such reduction, the net after-tax benefit received by Executive shall
      exceed the net after-tax benefit received by him if no such reduction was
      made. For purposes of this Section 1.4, "net after-tax benefit" shall mean
      (a) the Payments which Executive receives or is then entitled to receive
      from the Company that would constitute "parachute payments" within the
      meaning of Section 280G of the Code, less (b) the amount of all federal,
      state and local income taxes payable with respect to the foregoing
      calculated at the maximum marginal income tax rate for each year in which
      the foregoing shall be paid Executive (based on the rate in effect for
      such year as set forth in the Code as in effect at the time of the first
      payment of the foregoing), less (c) the amount of excise taxes imposed
      with respect to the payments and benefits described in (a) above by
      Section 4999 of the Code. The foregoing determination will be made by a
      nationally recognized accounting firm (the "Accounting Firm") selected by
      the Company (which may be, but will not be required to be, the Company's
      independent auditors). The Company will direct the Accounting Firm to
      submit its determination and detailed supporting calculations to both the
      Executive and the Company within fifteen (15) days after the date of
      termination of his employment. If the Accounting Firm determines that such
      reduction is required by this Section 1.4, the Executive, in his sole and
      absolute discretion, may determine which Payments shall be reduced to the
      extent necessary so that no portion thereof shall be subject to the excise
      tax imposed by Section 4999 of the Code, and the Company shall pay such
      reduced amount to him. The fees and expenses of the Accounting Firm for
      its services in connection with the determinations and calculations
      contemplated by this Section 1.4 will be borne by the Company.

1.5   No Duty to Seek Employment. Executive and the Company acknowledge and
      agree that nothing contained in this Amendment shall be construed as
      requiring Executive to seek or accept alternative or replacement
      employment in the event of his termination of employment by the Company
      for any reason, and no payment or benefit payable hereunder shall be
      conditioned on Executive's seeking or accepting such alternative or
      replacement employment.

2.    Reference to and Effect on the Employment Agreement



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      2.1   On and after the date hereof, each reference to "this Agreement,"
            "hereunder," "hereof," "herein," or words of like import shall mean
            and be a reference to the Employment Agreement as amended hereby. No
            reference to this Amendment need be made in any instrument or
            document at any time referring to the Employment Agreement. A
            reference to the Employment Agreement in any such instrument or
            document shall be deemed to be a reference to the Employment
            Agreement as amended hereby.

      2.2   Except as amended and/or superseded by this Amendment, the
            provisions of the Employment Agreement shall remain in full force
            and effect.

3.    Governing Law

      The Employment Agreement shall be governed by and construed in accordance
      with the laws of the State of New York without giving effect to principles
      of conflicts of laws.

4.    Counterparts

      This Amendment may be executed in two counterparts, each of which shall be
      deemed to be an original, but all of which together shall constitute one
      and the same instrument.


      IN WITNESS WHEREOF, the undersigned have executed this Amendment as of the
date first above written.

                                  EYETECH PHARMACEUTICALS, INC.


                                  By: /s/ DOUGLAS ALTSCHULER
                                      ----------------------------
                                  Name:  Douglas Altschuler
                                  Title:  Senior Vice-President/General Counsel


                                  EXECUTIVE


                                  /s/ DAVID R. GUYER
                                  -----------------------------
                                  Name:


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