Document:

<PAGE>

                                                                   Exhibit 10.34

                        AMENDMENT TO EMPLOYMENT AGREEMENT

         This AMENDMENT TO EMPLOYMENT AGREEEMENT, the ("Amendment") as and
between David Riggs ("Executive") and eXegenics, Inc., including its current,
former and future parents, agents, officers, directors, employees, successors,
assigns, predecessors and affiliated companies (the "Company"), collectively
referred to as the "Parties," is entered into effective the 30th day of March
2004.

         WHEREAS, the Company and Executive seek to amend certain terms of the
Parties' Employment Agreement, dated March 10, 2003, annexed hereto as Exhibit
A., (the "Employment Agreement") as set forth below and reach other
understandings related to Executive's employment;

         NOW THEREFORE, in consideration of the promises set forth below and
Executive's continued employment with the Company, the value and sufficiency of
which are hereby acknowledged by the Parties, the Parties agree as follows:

      1.    a.    Paragraph 3 of the Employment Agreement is deleted and
                  replaced as follows. "Position and Duties of Executive.
                  Executive shall serve the Company faithfully, diligently and
                  to the best of his ability as its President, Chief Executive
                  Officer, and Chief Financial Officer and shall devote all of
                  his full business time, energies and skill to his duties
                  hereunder and to the business and affairs of the Company and
                  will not, directly or indirectly, engage or participate in any
                  other business or professional activities during the
                  Employment Period. In this position, Executive shall perform
                  such executive and managerial duties and responsibilities
                  reasonably necessary to the operation of the Company and as
                  may be assigned to him from time to time by the Company's
                  Board of Directors. Executive shall report solely to the Board
                  and, during his employment and subject to the authority and
                  discretion of the Board, shall have responsibility for the
                  general management, day-to-day operations, and long term
                  planning of the Company."

            b.    Paragraph 4(c) of the Employment Agreement is revised by
                  adding the following as Paragraph 4(c)(iii): As of this date,
                  Executive shall be awarded a Second Option ("Second Option")
                  to purchase an additional 75,000 shares of the Company's
                  Common Stock. This Second Option granted shall vest in three
                  equal installments: The first immediately upon the grant date
                  (which grant date shall be the date on which the Board
                  approves this Amendment, the second on the first anniversary
                  of that date and the final upon the second anniversary of that
                  date. The Second Option shall be granted and subject to all
                  the terms and conditions of the Option Plan and shall be
                  evidenced by an agreement, which agreement shall provide,
                  among other things, that Executive shall have ten years to
                  exercise such option for a per share exercise price equal to
                  the fair market value of the Common Stock as of the date of
                  such option grant as

<PAGE>

                  determined in good faith by the Board (subject to forfeiture,
                  earlier termination and adjustment under certain circumstances
                  described more fully in the Option Plan and applicable option
                  agreement) and that:

                        i.    in the event of a Change of Control (as defined
                              below) in consequence of which Executive is
                              terminated by the Company or his salary,
                              responsibilities or title are diminished,
                              Executive shall be treated as having reached the
                              third anniversary date on which the Second Option
                              has been granted and the entire Second Option (to
                              the extent then not vested) shall be immediately
                              exercisable. The term "Change of Control" shall
                              mean: (i) a sale of all or substantially all of
                              the assets of the Company; (ii) a sale (including
                              an exchange) of all or fifty-one percent (51%) or
                              more of the shares of capital stock of the
                              Company; or (iii) the merger, consolidation,
                              amalgamation or like transaction of the Company
                              with or into another corporation.

                        ii.   if Executive is terminated by the Company without
                              Cause or is terminated by the Company in the event
                              of a Change of Control, all options (including the
                              Second Option and the options granted under the
                              Employment Agreement) shall remain exercisable for
                              two years following such termination.

            c.    Paragraph 5(a) of the Employment Agreement shall be deleted
                  and replaced with the following: "Reimbursement of Business
                  Related Expenses. From this date forward, the Company shall
                  reimburse Executive for all reasonable expenses upon the
                  presentation of reasonably itemized statements of such
                  expenses in accordance with the Company's policies and
                  procedures as in effect from time to time. Beginning May 1,
                  2004, expenses (including but not limited to airfare, lodging,
                  rental cars, etc.) relating to Executive's travel to and from
                  his residence in Illinois and Dallas, Texas (or any other
                  location where the Company is based) shall not exceed
                  $2,083.33 per month or $25,000 in any twelve (12) months; such
                  expenses incurred in the tax year 2004 and thereafter,
                  however, shall be treated by the Company as fringe benefits
                  and shall be includable in Executive's IRS form W-2 on a
                  gross-up basis".

            d.    Paragraph 8(h) of the Employment Agreement shall be modified
                  as follows: delete "State of Texas" and replace with "State of
                  New York."

      2.    Executive acknowledges and agrees that the Company's Board of
            Directors, and/or its agents, have not negatively impacted or
            interfered in any way with Executive's ability to review and/or sign
            any Company filings or certifications. Executive acknowledges and
            agrees that all such filings or certifications signed by Executive
            are done so freely and voluntarily.

<PAGE>

      3.    Executive acknowledges and agrees that he is not aware of any facts
            or circumstances that would give rise to any claims by Executive
            against the Company, including but not limited to a claim for
            violation of the Employment Agreement or a claim that he has grounds
            to terminate his employment for "Good Reason," as that term is
            defined under the Employment Agreement.

      4.    To the extent permitted by law, Executive agrees that if any other
            person or entity should file or initiate any complaint, charge,
            claim, proceeding, or lawsuit against the Company relating to any
            aspect of that person's employment, Executive will not voluntarily
            assist, support or participate in the bringing of any allegation
            against the Company. Executive further agrees to assist and
            cooperate with the Company in connection with the defense or
            prosecution of any claim that may be brought against or by the
            Company or any future investigation or dispute of any kind regarding
            the Company, as well as with the Board's efforts on behalf of the
            Company.

      5.    This Amendment represents the entire agreement of the Parties and
            shall supersede any and all previous contracts, arrangements,
            representations and understandings between the Company and the
            Executive, with the exception of the Employment Agreement and the
            documents referenced therein, on the particular issues herein. In
            the event of any conflict between the terms of this Amendment and
            the Employment Agreement, this Amendment shall govern. This
            Amendment may be modified only by mutual written agreement of the
            Parties.

      6.    This Amendment shall be binding upon, inure to the benefit of and be
            enforceable by the Executive and the Company, their respective
            heirs, executors, administrators, successors and assigns. In the
            event the Company is merged, consolidated or liquidated, or
            otherwise combined into one or more corporations, the provisions of
            this Agreement shall be binding upon and inure to the benefit of the
            parent corporation or the corporation resulting from such merger or
            to which the assets shall be sold or transferred, which corporation
            from and after the date of such merger, consolidation, sale or
            transfer shall be deemed to be the Company for purposes of this
            Amendment. This Amendment shall not be assignable by the Employee.

      7.    Executive acknowledges and agrees (i) that he is entering into this
            Amendment knowingly and voluntarily after carefully reviewing it;
            (ii) that he has had ample time to review the Amendment and has had
            the

<PAGE>

            opportunity to review the Amendment with his own counsel of his own
            choosing (not the Company's counsel); (iii) that he understands its
            final and binding effect; and (iv) that the only promises made to
            him to obtain his agreement and signature are those stated in this
            Amendment. The Parties participated jointly in the negotiation and
            preparation of this Amendment and each party has had the opportunity
            to obtain the advice of legal counsel and to review, comment upon
            and redraft it. Accordingly, it is agreed that no rule of
            construction shall apply against any party in favor or any party.
            This Amendment shall be construed as if the parties jointly prepared
            it, and any uncertainty or ambiguity shall not be interpreted
            against any on party in the favor of the other.

      8.    This Amendment and the Employment Agreement shall be construed and
            enforced in accordance with the laws of the State of New York,
            without regard to rules relating to conflict of laws. Any claims
            regarding this Amendment or the Employment Agreement, or alleged
            breach thereof, shall be brought exclusively in the State or Federal
            courts within the State of New York, with the Parties consenting to
            personal jurisdiction within the State of New York.

     IN WITNESS WHEREOF, the Company and the Executive have caused this
Agreement to be duly executed.

eXegenics, Inc.                             David E. Riggs

By: John A. Paganelli                       Signature: /s/ David E. Riggs
     ------------------------------                    -------------------------

Signature: /s/John A. Paganelli               Date: March 30, 2004
           ------------------------                 ----------------------------

Date: March 30, 2004
      -----------------------------<PAGE>
                                                                   Exhibit 10.35

[EXEGENICS LOGO]

April 10, 2003

Dorit Arad, D.Sc.
16901 Park Hill Drive
Dallas, Texas 75225

Dear Dr. Arad:

     In accordance with Section 6(d) and 7(a) of that certain Employment
Agreement, dated as of July 1, 2002 (the "Employment Agreement"), by and between
you and eXegenics, Inc. (the "Company"), please be advised that your employment
with the Company is to be terminated as of April 15, 2003 (the "Termination
Date"). (Capitalized terms used in this letter and not otherwise defined herein
shall have the meanings ascribed to such terms in the Employment Agreement.)

     While your employment with the Company has been terminated, we wish to
remind you of your obligations to cooperate with the Company in all matters
relating to the winding-up of your work with the Company under Section 7(d) of
the Employment Agreement. In connection with such required cooperation, please:

     a. take all actions and do all things reasonably necessary (including the
        completion of the plan of action annexed to this letter as Exhibit A) to
        ensure that all hardware, software, chemicals (novel, hazardous, and
        non-hazardous), data and information, including, without limitation,
        laboratory notebooks, relating to any and all research, experiments or
        other projects with which you have been involved on the Company's behalf
        (each, a "Project," and collectively, the "Projects") are properly
        updated, organized and stored in a manner which will facilitate the
        ongoing nature of any Project or the transfer of any Project (or
        information relating thereto) to a third party;

     b. prepare a summary of the status of any completed, on-going or future
        planned Project, such summary to include: (A) the purpose of the
        Project, (B) the date started (or anticipated date started), (C) the
        date of completion (or anticipated date of completion), (D) a list of
        the personnel involved (or to be involved) with such Project and their
        respective roles, (E) a description of each stage of the Project,
        including, if applicable, identification of which stages have been
        completed and which are on-going, and (F) a description of the
        importance of each such stage to a potential sale or other transfer of
        the Project to a third party;
<PAGE>

                                [EXEGENICS LOGO]

Dorit Arad, D.Sc.
April 8, 2003
Page 2

     c. prepare a summary of all biological and other experimental materials
        involved in any completed, ongoing or future planned Project, including
        (A) the nature of material (e.g., cell line, antibodies, bacterial
        strain, etc.), (B) personnel currently responsible for maintaining such
        material, (C) actions required to preserve the material, and (D) such
        other information as you deem relevant to the preservation of the
        material;

     d. prepare a summary of all patents and patent applications which relate to
        any Project or in which you have any right, title and interest and, if
        requested by the Company, shall assign by executing proper instruments
        of assignment any such right, title and interest to the Company;

     e. following completion of the above, return to the Company all documents
        (and any copies thereof and property of the Company in your possession,
        including, without limitation, all keys, badges, credit cards, phone
        cards, cellular phones, computers, etc.; and

     f. respond to all inquiries relating to your employment with the Company or
        any other issues that you were involved with or had knowledge of during
        the course of such employment that may be posed from time to time by the
        Company.

     Please be advised that your failure to comply with the foregoing shall
constitute a breach of the Employment Agreement and shall relieve the Company of
any further obligations thereunder (including, without limitation, the
obligation to make payments under Section 7(c) of the Employment Agreement or
under any provision of this letter) and, in addition to any other legal or
equitable remedy available to the Company, shall entitle the Company to recover
any consideration already paid to you pursuant to such terms.

     Any compensation payable to you from the date hereof through the
Termination Date shall be as specified in the Employment Agreement. As of the
Termination Date you will cease to accrue vacation days and any accrued vacation
owed to you as of the Termination Date will be paid out to you in your final
paycheck that will be issued on April 14, 2004.

     Pursuant to Section 7(c) of the Employment Agreement, the Company will
continue to pay you your current salary, based on the rate of $190,000 per
annum, for the twelve months following the Termination Date (or through April
14, 2004), payable in accordance with the Company's customary payroll practices.

<PAGE>

[EXEGENICS LOGO]

Dorit Arad, D.Sc.
April 8, 2003
Page 3

     As specified in the Employment Agreement, the effect of this termination on
your Initial Option and each Milestone Option, if any, shall be governed by the
applicable option agreements and the Company's Option Plan.

     You shall remain insured under the Company's health insurance plan through
the Termination Date, and your health insurance benefits will terminate as of
the day immediately following the Termination Date. The Company will provide you
with a separate notice regarding your rights under the Consolidated Omnibus
Budget Reconciliation Act of 1985 ("COBRA"), your eligibility to continue health
insurance coverage and the costs to you of same. If you elect to continue your
health insurance benefits pursuant to the terms of COBRA, the Company will
reimburse you for the COBRA premium payments paid by you with respect to
coverage for the first 90 days following the Termination Date, plus an amount
equal to your estimated federal income taxes on such reimbursement payments
based on a tax rate of 35.5%. Such payments shall be made to you promptly
following the Company's receipt of evidence of your election to continue health
insurance benefits pursuant to COBRA and your payment of premiums for such
90-day period. Your other benefits, which include a $600 per month car
allowance, shall terminate immediately.

     We further wish to remind you of your obligations under the Non-Competition
Agreement, dated as of August 19, 2002, by and between you and the Company, as
your obligations under such agreements survive the termination of your
employment.

     Please contact Ronald L. Goode, Ph.D., if you have any questions regarding
the foregoing.

                                             Very truly yours,
                                             EXEGENICS, INC.

                                             /s/ Ronald L. Goode
                                             ----------------------------------
                                             Ronald L. Goode, Ph.D.,
                                             Chairman of the Board of Directors
                                             of eXegenics, Inc.

Enclosures

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00064-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00064-of-00352.parquet"}]]