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                                                                   EXHIBIT 10.43

                              CONSULTING AGREEMENT

         This Consulting Agreement (this "Agreement") dated March 6, 2003 (the
"Effective Date"), between DOR BioPharma, Inc., a Delaware corporation (the
"Company") and Lance Simpson, Ph.D., ("Consultant").

         WHEREAS, the Company desires to engage Consultant to provide consulting
services to it in connection with its business; and

         WHEREAS, Consultant desires to provide consulting services to the
Company in connection with its business; and

         WHEREAS, Consultant has valuable expertise related to the development
of vaccines for botulinum toxin, being developed for the prevention of botulinum
toxin poisoning (the "Field"); and

         NOW THEREFORE, in consideration of the mutual promises and covenants
contained herein, and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties hereto agree as
follows:

         SECTION 1. Term of Agreement. Commencing on the Effective Date,
Consultant shall be retained by the Company for a period of three (3) years,
which shall be renewable upon mutual agreement of the parties for additional one
year periods. The initial period and any extensions or renewals thereof shall
constitute the "Consulting Term." This agreement is contingent on the signing of
the license agreement between DOR BioPharma, Inc. and Thomas Jefferson
University ("License Agreement").

         SECTION 2. Position and Responsibilities.

                  (a) In order to protect the Company's patent rights, any
actual research done by Consultant under this Agreement, if any, shall be done
at the Company's place of business or at some other location approved in advance
by the Company and no research under this Agreement, if any, shall be done by
Consultant at his employer's place of business unless the Company has an
agreement with such employer to conduct such research. Consultant shall serve as
a consultant to the Company and render such advice and services to the Company
as may be reasonably requested by the Company including, without limitation,
advising the Company with respect to the direction of the Company's research and
product development activities. Subject to the terms, limitations and conditions
set forth herein, Consultant agrees to undertake on a best-efforts basis such
consultative and advisory services as the Company shall reasonably request in
connection with the Company's business.

         SECTION 3. Limitations.

                  (a) Consultant acknowledges that at the time of this Agreement
he is under no other obligation to any third party that would interfere with his
rendering consulting services to the Company.

                  (b) The Company acknowledges that the Consultant is not a
"Contract Research Organization" or "Sponsor" as defined in Title 21 of the U.S.
Code of Federal



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Regulations, and the Company shall retain full responsibility for the content of
certain documents and regulatory submission, for interpretation of the data
contained therein and for the timing, preparation and processing of regulatory
submissions.

                  (c) The Company acknowledges that the Consultant shall at all
times during the term of this Agreement act as an independent contractor and not
as an employee or agent of the Company, and shall not assume or incur any
benefits, rights or obligations related to said employee or agent status.
Neither party hereto shall be authorized to act as the agent for the other, nor
shall either be bound by the acts of the other, except as otherwise specifically
provided in this Agreement.

                  (d) The Company acknowledges that the Consultant's primary
employment responsibility is to the Thomas Jefferson University, Department of
Medicine ("TJU"), and that Consultant is bound by TJU employment and business
conduct and policies, including those related to consulting and extramural
activities, and that Consultant's obligations under TJU's policies takes
priority over any obligations that Consultant may incur to the Company pursuant
to this Agreement. Furthermore, TJU, as employer of Consultant, places certain
limitations upon the total amount of time that may be spent on Consultant's
activities that are not related to his employment by TJU, and the Company agrees
that those limitations, which are subject to change at the sole discretion of
TJU, shall not be exceeded by the Company's requests for Consultant's services.
The Company further acknowledges that all such consulting services must take
place at such times when the Consultant is not otherwise engaged in activities
related to his employment with TJU. This agreement is subject to the rules
governed by the TJU and the Jefferson Medical Center.

                  (e) The parties hereto agree that the Consultant's services to
the Company shall not include proprietary information of TJU, nor make use of
TJU's time or resources, without prior written agreement of TJU. Additionally,
the parties agree that the Consultant's services shall not restrict or hinder
the ability to conduct current or foreseeable research assignments with TJU,
nor, unless otherwise agreed, limit Consultant's ability to publish work
generated at or on the behalf of TJU.

                  (f) Nothing contained in this Agreement shall be construed as
granting any right to the Company to use in advertising, publicity, or other
promotional activities the name of the Consultant, without the prior written
consent of the Consultant, provided, however, that the Company may use the names
of the Consultant, in various documents used by the Company for capital raising
and financing or where the use of such names may be required by law, without
such prior written consent.

         SECTION 4. Compensation.

                  (a) As compensation for the performance of his duties on
behalf of the Company, Consultant shall be compensated during the Consulting
Term with an option to purchase at the rate of one hundred thousand shares
(100,000) Company Common Stock. Such options shall vest one third (1/3) upon the
execution date of this agreement, one third (1/3) upon twelve months from the
execution date of this Agreement and one third (1/3) upon twenty-four months
from the execution date of this Agreement. Such annual grant of stock options
shall have the exercise price of the closing bid price on the American Stock
Exchange (AMEX). Upon the anniversary of the this Agreement, the Consultant have
the option to receive forty thousand


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dollars ($40,000) cash compensation or an option to purchase Company
Common Stocks which have a equivalent fair market value of forty thousand
dollars ($40,000). Such stocks shall vest quarterly in advance within a year.

                  (b) Consultant will file his own tax returns on the basis of
his status as an independent contractor for the reporting of all income, social
security, employment and other taxes due and owing on the consideration received
by him under this Agreement. Consultant shall be solely responsible for, and
shall pay, such taxes in accordance with applicable law. Similarly, Consultant
shall not be entitled to benefits specifically associated with employment
status, such as medical, dental and life insurance, stock or stock options of
the Company and shall not be entitled to participate in any other Company
benefit programs. As an independent contractor, Consultant acknowledges,
understands and agrees that he is not, and shall not represent himself to third
parties as being, the agent or representative of the Company nor does he have,
and shall not represent himself to third parties as having, actual or apparent
power or authority to do or take any action for or on behalf of the Company, as
its agent, representative or otherwise, except as specifically set forth herein.

         SECTION 5. Expenses. The Company shall reimburse Consultant for all
normal, usual and necessary expenses incurred by Consultant in furtherance of
the business and affairs of the Company against receipt by the Company of
appropriate vouchers or other proof of the Company's expenditures and otherwise
in accordance with such expense- reimbursement policy as may from time to time
be adopted by the Company.

         SECTION 6. Confidential Information.

                  (a) Consultant agrees that during the course of his Consulting
Term or at for a period of five (5) years after termination, he will keep in
strictest confidence and will not disclose or make accessible to any other
person without the written consent of the Company, the Company's products,
services and technology, both current and under development, promotion and
marketing programs, lists, trade secrets and other confidential and proprietary
business information of the Company or any of its clients and third parties
including, without limitation, Proprietary Information (as defined in Section 7)
(all the foregoing is referred to herein as the "Confidential Information").
Consultant agrees: (i) not to use any such Confidential Information for himself
or others; and (ii) not to take any such material or reproductions thereof from
the Company's facilities at any time during his Consulting Term except, in each
case, as required in connection with Consultant's duties to the Company.

                  Notwithstanding the foregoing, the parties agree that
Consultant is free to use (i) information in the public domain not as a result
of a breach of this Agreement, (ii) information lawfully received from a third
party who had the right to disclose such information and (iii) Consultant's own
independent skill, knowledge, know-how and experience to whatever extent and in
whatever way he wishes, in each case consistent with his obligations as
Consultant and that, at all times, Consultant is free to conduct any
non-commercial research not relating to the Company's business.

                  (b) Except with prior written authorization by the Company,
Consultant agrees not to disclose or publish any of the Confidential Information
or any confidential, technical or business information of any other party to
whom the Company owes an obligation of confidence, at any time during or after
his engagement by the Company.



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                  (c) Upon written notice by the Company, Consultant shall
promptly redeliver to the Company, or, if requested by the Company, promptly
destroy all written Confidential Information and any other written material
containing any information included in the Confidential Information (whether
prepared by the Company, Consultant, or a third party), and will not retain any
copies, extracts or other reproductions in whole or in part of such written
Confidential Information (and upon request certify such redelivery or
destruction to the Company in a written instrument reasonably acceptable to the
Company and its counsel).

                  (d) In the event that Consultant is requested or required (by
oral questions, deposition, interrogatories, requests for information or
documents, subpoena, civil investigative demand or other process) to disclose
all or any part of any Confidential Information, Consultant will provide the
Company with prompt notice of such request or requirement, as well as notice of
the terms and circumstances surrounding such request or requirement, so that the
Company may seek an appropriate protective order or waive compliance with the
provisions of this Agreement. In such case, the parties will consult with each
other on the advisability of pursuing any such order or other legal action or
available steps to resist or narrow such request or requirement. If, failing the
entry of a protective order or the receipt of a waiver hereunder, Consultant is,
in the opinion of counsel reasonably acceptable to the Company, legally
compelled to disclose Confidential Information, Consultant may disclose that
portion of such information which counsel advises Consultant that it is legally
compelled to disclose. In any event, Consultant will use its best efforts to
obtain and will not oppose action by the Company to obtain, an appropriate
protective order or other reliable assurance that confidential treatment will be
accorded the disclosure of such information.

SECTION 7.  Ownership Of Proprietary Information.

                  (a) Consultant agrees that all information that has been
created, discovered or developed by the Company, its subsidiaries, affiliates,
licensors, licensees, successors or assigns (collectively, the "Affiliates"),
during the Consulting Term and information relating to the Company's customers,
suppliers, consultants, and licensees, and/or in which property rights have been
assigned or otherwise conveyed to the Company or the Affiliates, shall be the
sole property of the Company or the Affiliates, as applicable, and the Company
or the Affiliates, as the case may be, shall be the sole owner of all patents,
copyrights and other rights in connection therewith, including without
limitation the right to make application for statutory protection. All the
aforementioned information is hereinafter called "Proprietary Information."

                  (b) Notwithstanding any other provision to the contrary, the
Company will have no rights, solely by reason of this Agreement, in any
document, material, invention, information, improvement or other intellectual
property whatsoever, whether or not publishable, patentable or copyrightable
that is or was generated as a result of the Consultant's activities as an
employee of TJU or using proprietary information or resources of TJU.

         SECTION 8. Termination.

         The Company shall have the absolute right to terminate this Agreement
at any time upon thirty (30) days' prior written notice to Consultant; provided,
however, that in the event of termination pursuant to this Section, the Company
shall be obligated to continue to pay the Consulting Fee until the earlier of
(a) the end of the Consulting Term and (b) the termination of



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the License Agreement entered into by and between the Company and Thomas
Jefferson University (the "License Agreement").

         SECTION 9. Notices. Any notice or other communication under this
Agreement shall be in writing and shall be deemed to have been given: when
delivered personally against receipt therefor; one day after being sent by
Federal Express or similar overnight delivery; or three days after being mailed
registered or certified mail, postage prepaid, to a party hereto at the address
set forth below, or to such other address as such party shall give by notice
hereunder to the other party to this Agreement.

If to Company:

DOR BioPharma, Inc.
28101 Ballard Drive
Lake Forest, IL 60045
Tel: 847-573-8990
Fax: 847-573-9285
Attn: President

If to Consultant:

Lance Simpson, Ph.D
c/o Thomas Jefferson University
Room 314-JAH
1020 Locust Street
Philadelphia, PA 19107
Phone: 215-955-8381
Fax: 215-955-2169

         SECTION 10. Severability Of Provisions. If any provision of this
Agreement shall be declared by a court of competent jurisdiction to be invalid,
illegal or incapable of being enforced in whole or in part, the remaining
conditions and provisions or portions thereof shall nevertheless remain in full
force and effect and enforceable to the extent they are valid, legal and
enforceable, and no provision shall be deemed dependent upon any other covenant
or provision unless so expressed herein.

         SECTION 11. Entire Agreement; Modification. This Agreement is the
entire agreement of the parties relating to the subject matter hereof and
thereof, and the parties hereto and thereto have made no agreements,
representations or warranties relating to the subject matter of this Agreement
which are not set forth herein or therein. No amendment or modification of this
Agreement shall be valid unless made in writing and signed by each of the
parties hereto.

         SECTION 12. Binding Effect. The rights, benefits, duties and
obligations under this Agreement shall inure to, and be binding upon, the
Company, its successors and assigns, and upon Consultant and his legal
representatives. This Agreement constitutes a personal service agreement, and
the performance of Consultant's obligations hereunder may not be transferred or
assigned by Consultant and any such purported transfer or assignment shall null
and void ab initio.



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         SECTION 13. Governing Law. This Agreement shall be governed by, and
construed and interpreted in accordance with, the laws of the State of Florida
without regard to such State's principles of conflict of laws. The parties
irrevocably and unconditionally agree that the exclusive place of jurisdiction
for any action, suit or proceeding ("Actions") relating to this Agreement shall
be in the courts of the United States of America sitting in the city, state and
county of Florida, or, if such courts shall not have jurisdiction over the
subject matter thereof, in the courts of the State of Florida sitting therein,
and each such party hereby irrevocably and unconditionally agrees to submit to
the jurisdiction of such courts for purposes of any such Actions. If any such
State court also does not have jurisdiction over the subject matter thereof,
then such an action, suit or proceeding may be brought in the federal or state
courts located in the states of the principal place of business of any party
hereto. Each party irrevocably and unconditionally waives any objection it may
have to the venue of any Action brought in such courts or to the convenience of
the forum. Final judgment in any such Action shall be conclusive and may be
enforced in other jurisdictions by suit on the judgment, a certified or true
copy of which shall be conclusive evidence of the fact and the amount of any
indebtedness or liability of any party therein described.

         SECTION 14. Assignability.

                  This Agreement and the rights and duties hereunder may not be
assigned by either party without first obtaining the written consent of the
other, which consent will not be unreasonably withheld. Any such purported
assignment, without the written consent of the other party, will be null, void
and of no effect. Notwithstanding the foregoing, the Company may assign this
Agreement (i) to a purchaser, merging or consolidating corporation, or acquirer
of substantially all of the Company's assets or business and/or pursuant to any
reorganization qualifying under section 368 of the Internal Revenue Code of 1986
as amended, as may be in effect at such time, or (ii) to an Affiliate of the
Company without such prior written consent.

         SECTION 15. Headings. The headings of the Sections are inserted for
convenience of reference only and shall not affect any interpretation of this
Agreement.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year first written above.

CONSULTANT:

--------------------------
Name: Lance Simpson, Ph.D.

DOR BIOPHARMA INC.

by:
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Name:    Steve H. Kanzer
Title:   Vice Chairman




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